WO2025219135A1

WO2025219135A1 - Process for utilizing high calorific acrylic acid production waste streams

Info

Publication number: WO2025219135A1
Application number: PCT/EP2025/059437
Authority: WO
Inventors: Simon Wachter; Xiu Shan TIAN; Jia Fei ZHANG; Hai Jiang
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2024-04-17
Filing date: 2025-04-07
Publication date: 2025-10-23
Anticipated expiration: 2026-10-17

Abstract

The present invention concerns a process for utilizing waste streams from an acrylic acid production plant by gasification and an acrylic acid production plant comprising the necessary units for utilizing waste streams generated during acrylic acid production, separation and upgrading. The process comprises a conversion of a high caloric first waste stream W1 and a further feedstock comprising coal and optionally also of at least one further waste stream W2, W5 and W6. The first waste stream W1 and the optional second waste stream W2 are separated from the separation unit of the acrylic acid production plant and the optional fifth waste stream W5 and sixth waste stream W6 are separated from the acrylic acid upgrading unit. The conversion by a gasification process in at least one gasifier results in synthesis gas which can then be utilized e.g., for production of chemicals such as acrylic acid in a chemical production plant.

Description

Process for utilizing high calorific acrylic acid production waste streams

Technical area

The present invention relates to a process utilizing high calorific acrylic acid production waste streams, an acrylic acid plant comprising an integrated production waste stream treatment facility and the use of said plant for said process.

Background of the invention

Acrylic acid is an important commodity in the chemical industry. Accordingly, huge amounts of production waste streams are formed during synthesis and/or purification of crude acrylic acid and/or its upgrading into purified acrylic acid.

Acrylic acid is manufactured in an acrylic acid synthesis unit by a heterogeneously catalyzed gas phase partial oxidation from propene as a starting material which results in a product gas mixture. Crude acrylic acid is then separated from the product gas mixture in an acrylic acid separation unit by methods such as condensation and absorption. The crude acrylic acid is then further purified in an acrylic acid upgrading unit by methods such as distillation, crystallization, or variants of said methods such as solvent-added distillation, solvent-free distillation, azeotropic distillation and combinations of extraction and distillation. Said methods can be combined in said acrylic acid upgrading unit. A general description of acrylic acid manufacture and purification of crude acrylic acid is disclosed in Ullmann's Encyclopedia of Industrial Chemistry, Chapter "Acrylic acid and derivatives”, T. Ohara et al., pages 6-10 (DOI: 10.1002/14356007.a01_161.pub4).

A standard method for treatment of waste streams from acrylic acid production is incineration of said waste streams for example in a boiler in which steam can be produced. Thereby, undesired CO2 is formed.

Another process for treating acrylic acid production waste streams is disclosed in CN117263793A. The process disclosed therein comprises the following steps: (1) a heavy component diluent blending process; (2) a light component de-aldehyding process; (3) a light component maleic anhydride removal process; optionally, (4) a waste gas recycling process.

It is an objective of the present invention to utilize the high calorific acrylic acid production waste streams described above in a more environmentally friendly way than incineration and the above-described process comprising four steps.

It is a further objective of the present invention to provide a process and a production plant which convert at least a portion of the high calorific production waste streams into feedstocks for the chemical industry.

Summary of the invention

These problems are solved by a process for utilizing at least one high calorific waste stream from an acrylic acid production plant, wherein the acrylic acid production plant comprises a) an acrylic acid production unit AAPU, b) an acrylic acid separation unit AASU, and c) an acrylic acid upgrading unit AAUU, the process comprising the steps

(i) providing a first waste stream W1 , wherein the first waste stream W1 is separated from the acrylic acid separation unit AASU and wherein the first waste stream W1 is a high calorific waste stream and optionally at least one of the second waste stream W2, the fifth waste stream W5 and the sixth waste stream W6, wherein the optional second waste stream W2 is separated from the acrylic acid separation unit AASU and wherein the optional second waste stream W2 is an aqueous waste stream, wherein the optional fifth waste stream W5 is separated from the acrylic acid upgrading unit AAUU, wherein the optional fifth waste stream W5 is a high calorific waste stream, wherein the optional sixth waste stream W6 is separated from the acrylic acid upgrading unit AAUU and wherein the optional sixth waste stream W6 is an aqueous waste stream,

(ii) optionally pretreating the first waste stream W1 and/or at least one of the optional waste streams W2, W5 and W6,

(ill) providing a further feedstock F, wherein the further feedstock F comprises coal,

(iv) optionally pretreating the further feedstock F, whereby a pretreated further feedstock PF is formed and

(v) subjecting the first waste stream W1 , optionally pretreated in step (ii), and the further feedstock F and/or the pretreated further feedstock PF, and optionally, at least one of the optional waste streams W2, W5 and W6 to a gasification process at a temperature between 800 and 1500 °C, wherein said gasification process comprises at least one gasifier G and whereby a gas stream GS1 is formed by said gasification process.

These problems are further solved by an acrylic acid plant comprising an integrated waste stream treatment facility wherein said acrylic acid plant comprises a) an acrylic acid production unit AAPU, b) an acrylic acid separation unit AASU downstream and fluidically connected to the acrylic acid production unit AAPU, said acrylic acid separation unit AASU purging a first waste stream W1, c) an acrylic acid upgrading unit AAUU, downstream and fluidically connected to the acrylic acid separation unit AASU, d) at least one gasifier G, downstream and directly or indirectly fluidically connected to the acrylic acid separation unit AASU and optionally also directly or indirectly fluidically connected to the acrylic acid upgrading unit AAUU, wherein said at least one gasifier G is a plasma gasifier or an entrained-flow gasifier.

Figure 1 shows the process and the acrylic acid plant according to the present invention utilizing waste streams separated from the acrylic acid separation unit AASU together with a further feedstock, dotted lines represent optional waste streams and process units.

Figure 2 shows the process and the acrylic acid plant according to the present invention utilizing waste streams separated from the acrylic acid separation unit AASU together with a pretreated further feedstock, dotted lines represent optional waste streams and process units.

Figure 3 shows the process and the acrylic acid plant in another aspect of the invention utilizing waste streams separated from the acrylic acid separation unit AASU together with a further feedstock and optionally utilizing further waste streams separated from the acrylic acid upgrading unit AAUU, dotted lines represent optional waste streams and process units.

Figure 4 shows the process and the acrylic acid plant in another aspect of the invention utilizing waste streams separated from the acrylic acid separation unit AASU together with a pretreated further feedstock and optionally utilizing further waste streams separated from the acrylic acid upgrading unit AAUU, dotted lines represent optional waste streams and process units.

Detailed description of the invention

The present invention is further described below with reference to the embodiments, but the present invention is not limited to these embodiments, and any modifications of these embodiments, combinations of these embodiments or substitutions within the basic spirit of the present invention are still within the scope of the present invention as claimed.

Definitions:

In the context of the present description and the accompanying claims, the term "about” preferably means a deviation of the thus described value of ±10 %. In the context of the present invention, the term “combinations thereof' is inclusive of one or more of the recited elements. In the context of the present invention, the term “mixture thereof” is inclusive of one or more of the recited elements.

“Refuse-derived fuel” (RDF) is defined herein as a fuel produced from various types of waste such as municipal solid waste (MSW), industrial waste or commercial waste. RDF consists largely of combustible components of such waste, as non-recyclable plastics (preferably not including PVC), paper cardboard, labels, and other corrugated materials. These fractions are separated by different processing steps, such as screening, air classification, ballistic separation, separation of ferrous and non-ferrous materials, glass, stones, and other foreign materials and shredding into a uniform grain size, or also pelletized to produce a homogeneous material which can be used as a feedstock for gasification processes (Y. Yang et al., Gasification of refuse-derived fuel from municipal solid waste for energy production: a review, Environmental Chemistry Letters (2021) 19, 2127-2140 (https://doi.org/10.1007/s10311-020- 01177-5).

“Coal” is a combustible organic sedimentary rock that is formed from the accumulation and preservation of plant materials, usually in a swamp environment and defined herein as a fossil feedstock for gasification.

“Tar oil slurry” is defined herein as a non-gaseous residue from a fixed-bed gasifier Fl BG in which the further feedstock F is converted to a pretreated feedstock PF which is then fed into the at least one gasifier G. Tar oil slurry is optionally comprised in said pretreated feedstock PF. Such tar oil slurry has a high ash content.

The term “downstream of” is defined herein in respect to a succession of unit operations as located next to on the side which is in the flow direction of fluids passing said succession of unit operations.

The term “fluidically connected to” in respect to two or more units is defined herein that a fluid such as a particulate solid, liquids, gases, and mixtures thereof can flow from one of such unit to the other such unit and flow through and/or along such an analytical unit. Two units “fluidically connected to” each other are for example connected by one or more pipes which each other or by screw conveyors or by extruders or by solids pumps.

“Reactive distillation” is defined herein as a process where the chemical reactor is also the still. In contrast, “solvent- added distillation”, “solvent-free distillation”, “azeotropic distillation”, “distillation” and combinations of “extraction” and “distillation” are not considered as “reactive distillation” herein. "Solvent-free distillation” is defined herein as a distillation for which no extra solvent is added to the mixture which is subjected to the distillation process.

The process for utilizing waste streams from an acrylic acid production plant according to the present invention is schematically shown in Figures 1 and 2 and is described below in detail.

Several processes to produce acrylic acid are known und commercially used. In general, such processes utilize an acrylic acid production plant comprising an acrylic acid production unit AAPU, an acrylic acid separation unit AASU which is downstream and fluidically connected to said acrylic acid production unit AAPU, and an acrylic acid upgrading unit AAUU which is downstream and fluidically connected to said acrylic acid separation unit AASU.

In the acrylic acid production unit AAPU, usually two separate reaction steps are utilized. The product stream formed in the acrylic acid production unit AAPU from the starting material(s) SM is a "product gas mixture” PGM which comprises acrylic acid.

The product gas mixture PGM formed in the acrylic acid production unit AAPU is then fed into the acrylic acid separation unit AASU which is downstream of and fluidically connected to the acrylic acid production unit AAPU. Crude acrylic acid is then separated from the product gas mixture PGM in an acrylic acid separation unit AASU. Crude acrylic acid CAA is then purified in the acrylic acid upgrading unit AAUU whereby upgraded acrylic acid UAA is formed.

The preparation of acrylic acid in the acrylic acid production unit AAPU is described hereinafter in more detail: the gas phase partial oxidation itself can be conducted as described in the prior art. Proceeding from propene as starting material SM, the gas phase partial oxidation can be conducted, for example and preferably, in two successive oxidation stages, as described in EP 0 700 714 A1 and in EP 0 700 893 A1. It is of course also possible to employ for example the gas phase partial oxidations cited in DE 197 40 253 A1 and in DE 197 40 252 A1.

In principle, the gas phase partial oxidation can also be conducted as described in documents US 2006/0161019, WO 2006/092410, WO 2006/002703, WO 2006/002713, WO 2005/113127, DE 10 2004 021 763 A1, EP 1 611 076 A1, WO 2005/108342, EP 1 656 335 A1, EP 1 682 478 A1, EP 1 682 477 A1, DE 10 2006 054214 A1, DE 10 2006 024 901 A1, EP 1 611 080 A2, EP 1 734030 A1, DE 10 2006 000 996 A1, DE 10 2005062 026 A1, DE 10 2005 062 010 A1, WO 2007/060036, WO 2007/051750 and WO 2007/042457. The propene source used for this purpose may be polymer grade propene or chemical grade propene according to DE 102 32 748 A1. If the C3 precursor used is propane, the partial oxidation can be also conducted as described in DE 102 45 585 A1.

Typically, the acrylic acid-comprising product gas mixture PGM from a heterogeneously catalyzed gas phase partial oxidation of C3 starting materials SM (preferably propene) of acrylic acid with molecular oxygen over catalysts in the solid state as described above may have, for example, the following contents: 1% to 30% by weight of acrylic acid, 0.05% to 10% by weight of molecular oxygen, 1% to 30% by weight of water, > 0% to 5% by weight of acetic acid, > 0% to 3% by weight of propionic acid, > 0% to 1% by weight of maleic acid and/or maleic anhydride, 0% to 2% by weight of acrolein, 0% to 1 % by weight of formaldehyde, > 0% to 1 % by weight of furfurals, > 0% to 0.5% by weight of benzaldehyde, 0% to 1% by weight of propene, and as the remaining amount essentially inert gases, for example nitrogen, carbon monoxide, carbon dioxide, methane and/or propane. Next, the product gas mixture PGM formed in the acrylic acid production unit AAPU is then fed into an acrylic acid separation unit AASU which is downstream of and fluidically connected to the acrylic acid production unit AAPU.

The acrylic acid separation unit AASU can utilize different methods for separating crude acrylic acid CAA from the product gas mixture PGM, for example, one or more absorption columns or one or more condensers. Furthermore, a first waste stream W1 and a third waste stream W3 are separated from the product gas mixture PGM in the acrylic acid separation unit AASU.

The specific set-up of the acrylic acid separation unit AASU depends on the acrylic acid upgrading method applied in the acrylic acid upgrading unit AAUU and the successive upgrading method employed to obtain upgraded acrylic acid UAA from crude acrylic acid CAA.

Usually, a first waste stream W1 and a third waste stream W3 are also separated from the production gas mixture PGM in the acrylic acid separation unit AASU. In some acrylic acid plant configurations, also a second waste stream W2 is separated in the acrylic acid separation unit AASU from the production gas mixture PGM.

In a preferred aspect of the present invention, the acrylic acid separation unit AASU comprises one absorption column, in which a first waste stream W1 , a second waste stream W2 and a third waste stream W3 are separated from the product gas mixture PGM. Optionally, the product gas mixture PGM is cooled down in an optional quench unit before entering said absorption column. The optional quench unit may be any of the apparatuses known from this purpose in the prior art (for example an empty column without internals in which the product gas mixture PGM enters said column at the top and the liquid is sprayed into said column via spray nozzles, spray scrubbers, Venturi scrubbers, bubble columns or other apparatuses with surfaces over which liquid trickles), preference being given to using Venturi scrubbers or spray coolers. The absorption column comprises at least one bottom section outlet, at least one top section outlet and at least one middle section outlet.

The crude acrylic acid CAA is leaving said absorption column through a middle section outlet, preferably a first middle section outlet. The first waste stream W1 is leaving said absorption column through the bottom section outlet of said absorption column. The second waste stream W2 is leaving said absorption outlet through a second middle outlet of said absorption column wherein said second middle section outlet is closer to the top section outlet of said absorption column than the first middle section outlet. The third waste stream W3 is leaving said absorption column through the top section outlet of said absorption column.

The site of introduction for the product gas mixture PGM from the acrylic acid production unit AAPU that has been quenched (or cooled in some other way or not cooled) into the absorption column in this preferred aspect of the present invention is advantageously in the bottom space of that column, which advantageously comprises a centrifugal droplet separator in integrated form and is generally separated from the lowermost separating internal by a first chimney tray which is preferably above the inlet of the column. In that case, first waste stream W1 (= high boiler fraction” of the product gas mixture PGM) is constantly directed into the bottom of the column via a connecting conduit or via an overflow. In an illustrative and preferred execution variant (which is described exclusively hereinafter without restriction of general ability for implementation), this is the first dual-flow tray of a first series of dual-flow trays that are appropriately arranged equidistantly. The chimney tray functions simultaneously as collecting tray, whereby the first waste stream W1 stays below said chimney tray. The first waste stream W1 is withdrawn continuously and at least a portion thereof is run into the bottom space and therefrom separated from said column. The first series of dual-flow trays is concluded by a second chimney tray (collecting tray). From this second chimney tray, in the first side draw, crude acrylic acid is withdrawn continuously as medium boiler fraction, preferably having a purity of > 90% by weight or > 95% by weight.

The second waste stream W2 is withdrawn continuously from the third collecting tray in the second side draw. A portion of the second waste stream W2 withdrawn is recycled into the column at the uppermost of the crossflow mass transfer trays. Another portion of the second waste stream W2 withdrawn is cooled by indirect heat exchange, appropriately split, and likewise recycled into the column. A cooled portion is recycled here to the uppermost valve tray (at a temperature of 15 to 30°C, preferably 20 to 25°C), and the other cooled portion to a valve tray disposed roughly in the middle between the third collecting tray and the uppermost valve tray (at a temperature of 20 to 35°C, preferably 25 to 30°C). The amount of crude acrylic acid CAA present can be separated in accordance with the invention from the residual amount of the second waste stream W2 withdrawn. The second waste stream W2 comprises about 70 to 85 wt.-% water.

Constituents that are more volatile than water are drawn off in gaseous form as third waste stream W3 at the top of said column and is normally recycled into the acrylic acid production unit AAPU as diluent gas (cycle gas). The portion of the third waste stream W3 is not recycled into the production unit AAPU as diluent gas is normally sent to incineration.

In another preferred aspect of the present invention, a portion of water comprised in the second waste stream W2 is removed from the second waste stream W2 in step (iii), for example, in a means suitable for evaporating water from a liquid mixture, such as an evaporator. More preferably, at least 50 wt.-% of the water and most preferably at least 70 wt.-% or 80 wt.-% of the water comprised in the second waste stream W2 are removed from the second waste stream W2 in step (iii). The calorific value of the second waste stream W2 is increased by water removal in step (iii). Thereby, the gasification process of step (iv) in presence of the second waste stream W2 is improved. This embodiment is particularly preferred in case the acrylic acid production plant comprises an acrylic acid separation unit AASU with one absorption column and an acrylic acid upgrading unit AAUU utilizing crystallization as purification method.

In case the acrylic acid separation unit AASU which comprises two or more absorption columns the waste streams may consist of the first waste stream W1 and the third waste stream W3 only. In all such processes, the first waste stream W1 is separated in one or more absorption columns as bottom product and the third waste stream W1 is separated as a gas mixture on one or more absorption columns as top product. The further treatment of the first waste stream W1 and the third waste stream W3 is the same as in case of the first waste stream W1 and the third waste stream W3 are separated from an acrylic acid separation unit AASU comprising only one absorption column as described above.

The crude acrylic acid CAA leaving the acrylic acid separation unit AASU is then fed into the acrylic acid upgrading unit AAUU from which upgraded acrylic acid UAA in the desired purity grade is obtained. Desired purity grades of acrylic acid are for example > 98 % for utilization of acrylic acid in a successive esterification reaction in the production of acrylates and > 99 % for utilization of acrylic acid in the production of polymers. Crude acrylic acid (CAA) has a purity in the range of 60 to 90 %. The acrylic acid upgrading unit AAUU can utilize different methods for purifying the crude acrylic acid CAA into the upgraded acrylic acid UAA, said methods comprise crystallization, solvent-added distillation, solvent-free distillation, azeotropic distillation, reactive distillation, extraction, and combinations thereof.

Purification methods applied in the acrylic acid upgrading unit AAUU comprise distillation or crystallization. The acrylic acid upgrading unit AAUU is downstream of and fluidically connected to the acrylic acid separation unit AASU.

The acrylic acid separation unit AASU comprising one absorption column as described in detail above is preferably combined with an acrylic acid upgrading unit AAUU utilizing either crystallization or distillation as purification method. Said distillation method is preferably a solvent-free distillation method i.e., in which no extra solvent is added.

A preferred type of acrylic acid upgrading unit AAUU utilizing crystallization as purification method which is preferably combined in an acrylic acid production plant with an acrylic acid separation unit AASU comprising one absorption column wherein said one absorption column separates the product gas mixture PGM into crude acrylic acid, a first waste stream W1, a second waste stream W2 and a third waste stream W3 is described in more detail below:

The crystallization method to be used is not subject to any restriction in principle. The crystallization can be conducted continuously or batchwise, in one or more stages, up to any degree of purity.

The crystallization can be for example executed as a suspension crystallization, as described in column 10 of DE 199 24 532 A1 or in example 1 of DE 102 23 058 A1 (for example in a cooling disk crystallizer as described in WO 2006/111565). The acrylic acid crystals formed in suspension crystallization can be separated from the remaining mother liquor in the case of esterification grade acrylic acid in a centrifuge (for example a 2- or 3-stage pusher centrifuge), in which case the crystals removed are advantageously washed on the centrifuge by means of molten pure crystals. If the suspension crystals are separated from the remaining mother liquor by means of a scrubbing column, for example a melt scrubbing column (for example one according to WO 01/77056, or DE 101 56 016 A1, or DE 102 23 058 A1, or as described in WO 2006/111565, WO 04/35514, WO 03/41833, WO 02/09839, WO 03/41832, DE 100 36 881 A1, WO 02/55469 and WO 03/78378). Crystallization can also be performed as a fractional falling film crystallization, as disclosed in EP 0 616 998 A1.

Another method which can be used in an acrylic acid upgrading unit AAUU to purify the crude acrylic acid CAA is solvent-free distillation (i.e., no further solvent is added for the distillation).

An acrylic acid upgrading unit AAUU utilizing solvent-free distillation can be for example combined with an acrylic acid separation unit AASU which comprises one or more absorption columns.

In a preferred aspect of the present invention, crystallization or solvent-free distillation is used in combination with an acrylic acid separation unit AASU which comprises one absorption column and purges a first waste stream W1, a second waste stream W2 and a third waste stream W3. This preferred aspect is shown in Figure 1 . Known processes represented by Figure 1 comprise SAC- and SAD-processes. The first waste stream W1 is provided in step (I). Optionally also the second waste stream W2 is provided in step (I). Further waste streams may be generated when using a method selected from the group comprising or consisting of solvent-added distillation, azeotropic distillation, extraction combined with distillation in the acrylic acid upgrading unit AAUU instead of crystallization or solvent-free distillation. The further waste streams which can be generated by said methods are fourth waste stream W4 which is a gaseous waste stream and is not suited as a feedstock for step (v) in the process according to the present invention, and/or a fifth waste stream W5 which is suited as feedstock in step (v) and is optionally provided in step (I) of the process according to the present invention, and/or a sixth waste stream W6 which is an aqueous waste stream and which is suited as a feedstock for step (v) and which is optionally provided in step (I) in the process according to the present invention. This aspect of the present invention is shown in Figure 2. Known acrylic acid production processes comprising at least one acrylic acid production unit AAPU, at least one acrylic acid separation unit AASU and at least one acrylic acid upgrading unit AAUU represented by Figure 2 comprise SAC- and SAD-processes.

The parameter ranges disclosed for waste streams W_x herein represent the respective composition of said waste streams prior to any pretreatment in optional step (ii) such as reducing the water content of an aqueous waste stream W2 and/or W6.

Analytical methods suitable for measuring the calorific value of a feedstock such as a waste stream W_x (x = 1 , 2, 5, 6) comprise combustion of a sample of said feedstock in a bomb calorimeter. Such methods are for example suitable to assess the thermochemical behavior of said feedstock during the gasification reaction and, accordingly, the suitable type of gasifier and gasification process parameters such as temperature, amount, and type of oxidant.

Analytical methods suitable for measuring the elemental composition such as the content of chemical elements H, C, 0, N, and S of a feedstock such as a waste stream W_x (x = 1 , 2, 5, 6) comprise CHNX analysis by combustion combined with thermal conductivity detection and/or infrared spectroscopy.

The first waste stream W1 has at least one, preferably all of the following properties: a) a calorific value in the range of 5 to 40 MJ/kg, more preferably of 7 to 35 MJ/kg and most preferably of 10 to 30 MJ/kg, b) a carbon content in the range of 30 to 80 wt.-%, more preferably 35 to 70 wt.-% and most preferably 40 to 70 wt.-%, c) a hydrogen content in the range of 2 to 8 wt.-%, more preferably 3 to 7 wt.-% and most preferably 3.5 to 6 wt.- %, d) an oxygen content in the range of 10 to 60 wt.-%, more preferably 15 to 55 wt.-% and most preferably 20 to 50 wt.-%, e) a nitrogen content in the range of 0.01 to 5 wt.-%, more preferably 0.025 to 2 wt.-% and most preferably 0.05 to 1 wt.-%, f) a sulfur content in the range of 0.025 to 5 wt.-%, more preferably 0.05 to 3 wt.-% and most preferably 0.1 to 2.5 wt.-%, wherein said first waste stream W1 is formed by the acrylic acid production process described herein in the acrylic acid production plant described herein.

The optional second waste stream W2 has at least one, preferably all of the following properties: a) a calorific value in the range of 1 to 40 MJ/kg, more preferably of 2 to 30 MJ/kg and most preferably of 3 to

15 MJ/kg, b) the second waste stream W2 preferably comprises less than 90 wt.-% water, more preferably less than

70 wt.-% water and most preferably less than 50 wt.-% water, c) a carbon content in the range of 1 to 30 wt.-%, more preferably 1 .5 to 25 wt.-% and most preferably 2 to

20 wt-%, d) a hydrogen content in the range of 2 to 20 wt.-%, more preferably 3 to 18 wt.-% and most preferably 5 to

15 wt.-%, e) an oxygen content in the range of 50 to 97 wt.-%, more preferably 57 to 95.5 wt.-% and most preferably 70 to 93 wt.-%, wherein said optional second waste stream W2 is formed by an acrylic acid production process described herein in the acrylic acid production plant described herein.

The optional third waste stream W3 has at least one, preferably all of the following properties: a) a carbon content of 0.5 to 8 wt.-%, b) a hydrogen content of 0.1 to 1 wt.-%, c) an oxygen content of 5 to 95 wt.-%, d) a nitrogen content of 0 to 95 wt.-%, e) a sulfur content of 0 to 4 wt.-%, wherein the sum of carbon content, hydrogen content, oxygen content, nitrogen content and sulfur content is at least 95 wt.-%. Said optional third waste stream W3 is formed by the acrylic acid production process described herein in the acrylic acid production plant described herein.

The optional fourth waste stream W4 has at least one, preferably all of the following properties: a) a carbon content of 0.5 to 8 wt.-%, b) a hydrogen content of 0.1 to 1 wt.-%, c) an oxygen content of 5 to 95 wt.-%, d) a nitrogen content of 0 to 95 wt.-%, e) a sulfur content of 0 to 4 wt.-%, wherein the sum of carbon content, hydrogen content, oxygen content, nitrogen content and sulfur content is at least 95 wt.-%. Said optional fourth waste stream W4 is formed by the acrylic acid production process described herein in the acrylic acid production plant described herein.

The optional fifth waste stream W5 has at least one, preferably all of the following properties: a) a calorific value in the range of 5 to 40 MJ/kg, more preferably of 7 to 35 MJ/kg and most preferably of 10 to 30 MJ/kg, b) a carbon content in the range of 30 to 80 wt.-%, more preferably 35 to 70 wt.-% and most preferably 40 to

70 wt.-%, c) a hydrogen content in the range of 2 to 8 wt.-%, more preferably 3 to 7 wt.-% and most preferably 3.5 to 6 wt.- %, d) an oxygen content in the range of 10 to 60 wt.-%, more preferably 15 to 55 wt.-% and most preferably 20 to 50 wt.-%, e) a nitrogen content in the range of 0.01 to 5 wt.-%, more preferably 0.025 to 2 wt.-% and most preferably 0.05 to 1 wt.-%, f) a sulfur content in the range of 0.025 to 5 wt.-%, more preferably 0.05 to 3 wt.-% and most preferably 0.1 to

2.5 wt.-%. Said optional fifth waste stream W5 is formed by the acrylic acid production process described herein in the acrylic acid production plant described herein.

The optional sixth waste stream W6 has at least one, preferably all of the following properties: a) a calorific value in the range of 1 to 40 MJ/kg, more preferably of 2 to 30 MJ/kg and most preferably of 3 to 15 MJ/kg, b) the optional sixth waste stream W6 preferably comprises less than 90 wt.-% water, more preferably less than 70 wt.-% water and most preferably less than 50 wt.-% water, c) a carbon content in the range of 1 to 30 wt.-%, more preferably 1 .5 to 25 wt.-% and most preferably 2 to 20 wt-%, d) a hydrogen content in the range of 2 to 20 wt.-%, more preferably 3 to 18 wt.-% and most preferably 5 to 15 wt.-%, e) an oxygen content in the range of 50 to 97 wt.-%, more preferably 57 to 95.5 wt.-% and most preferably 70 to 93 wt.-%.

Said optional sixth waste stream W6 is formed by the acrylic acid production process described herein in the acrylic acid production plant described herein.

Next, the first waste stream W1 and optionally at least one of the further waste streams selected from the group comprising or consisting of second waste stream W2, fifth waste stream W5 and sixth waste stream W6 is/are provided in step (I) is/are optionally pretreated in step (II).

The optional pre-treatment step (II) is described in the following: the first waste stream W1 may comprises particulate matter ("particles”). In this case, the first waste stream W1 is preferably pretreated in step (II) by grinding and/or heating. Methods for grinding and/or heating a feedstock are known to the skilled person and can be adapted as necessary to a given first waste stream W1. The technical effect of grinding as pretreatment for the first waste stream W1 is that particles which may cause plugging in pipes and other parts of the downstream equipment are reduced in size and thereby the risk of undesired plugging is minimized. The technical effect of heating as a pre-treatment of the first waste stream W1 is that the viscosity of the first waste stream w1 is reduced and thereby, the pumpability and spray ability of the first waste stream W1 are improved. Furthermore, undesired polymerization of the first waste stream W1 can be reduced or avoided.

The optional second waste stream W2 and/or the optional sixth waste stream W6 is/are preferably pretreated in step (ii) by reducing at least a portion of the water comprised in said waste streams(s). The amount of water comprised in the optional second waste stream W2 and/or waste stream W6, means for reducing the amount of water therein by e.g., evaporation and preferred water contents in the optional second waste stream W2 and/or sixth waste stream W6 after reduction of the water content and the desired effect of such a water content reduction are described above.

Next, a further feedstock F is provided in step (ill), wherein the further feedstock F comprises coal. Preferably, the further feedstock F comprises at least 25 wt.-% coal, more preferably at least 50 wt.-% coal and up to 100 wt.-% coal. The coal is selected from the group comprising or preferably consisting of meta-anthracite, anthracite, semianthracite, low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof. More preferably, the coal is selected from the group comprising or preferably consisting of low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof. Said terms are in accordance with the respective definition disclosed in ASTM D388-23. Accordingly, bituminous and anthracitic coals are summarized in ASTM D388-23 in "meta-terms” as "high rank coal”, and lignitic and subbituminous coals as "low rank coals”. Because real coal feedstocks used for gasification can be composed of more than one of said coal types according to ASTM D388-23, the "meta-terms” "high rank coals” and "low rank coals” are used in the examples section.

The coal comprised in the further feedstock F is optionally pretreated in step (iv). Preferably, the coal is pretreated in optional step (iv) by a method selected from the group comprising or preferably consisting of milling, grinding, classification, drying, converting the coal into a slurry and combinations thereof, whereby optionally coal dust as a side product is formed. Such pre-treatment methods are known to the skilled person and can be selected and applied for a given coal feedstock. Said coal dust can be also subjected to the gasification process in at least one gasifier G in step (v) and thereby further increase the yield in synthesis gas.

The further feedstock F preferably further comprises at least one second further feedstock SF selected from the group comprising or consisting of biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, 05 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, used oils, municipal solid waste (MSW), automotive shredder residue (ASR), natural gas, industrial waste streams and mixtures thereof.

The further feedstock F most preferably further comprises at least one second further feedstock SF selected from the group consisting of biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end-of-life tires, pyrolysis oils made from biomass, municipal solid waste (MSW), and mixtures thereof.

The second further feedstock SF is optionally pretreated before and/or pretreated after mixed with coal.

In case the coal comprised in further feedstock F is selected from coal, preferably from low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof, and said coal preferably having an average particle size of 1 mm to 10 cm, said further feedstock F is preferably pretreated in step (iii) in a fixed-bed gasifier FIBG in which said further feedstock F is converted to a pretreated further feedstock PF (schematically shown in Figures 2 and 4). Said pretreated feedstock PF is then co-fed in step (v) into the at least one gasifier G. A gas stream GSF comprising H2 and CO is also formed in said fixed-bed gasifier FIBG which is optionally combined with gas stream GS1. Optionally, milled coal is pretreated together with biomass and/or refuse-derived fuel (RDF) as second further feedstock SF in a fixed-bed gasifier Fl BG to form a pretreated further feedstock PF. Preferably, steam is also fed into the fixed-bed gasifier Fl BG during pre-treatment of the further feedstock F. More preferably, steam and oxygen are also fed into the fixed-bed gasifier Fl BG during pre-treatment of the further feedstock F.

In case the coal comprised in further feedstock F is selected from meta-anthracite, anthracite, semianthracite, low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof and having an average particle size of 100 m to 1 cm, and said further feedstock further comprises a second further feedstock SF selected from the group comprising or preferably consisting of biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end-of-life tires, pyrolysis oils made from biomass and mixtures thereof, such further feedstock F is preferably pretreated in step (iii) in a fixed-bed gasifier FIBG or a fluidized-bed gasifier FLBG in which said further feedstock F is converted into a pretreated further feedstock PF (schematically shown in Figures 2 and 4). Said pretreated feedstock PF is then co-fed in step (v) into the at least one gasifier G. A gas stream GSF comprising H2 and CO is also formed in said fixed-bed gasifier FIBG which is optionally combined with gas stream GS1.

The optional pre-treatment of the further feedstock F (either with or without a second further feedstock SF) preferably comprises a conversion of the further feedstock in at least one fixed-bed gasifier FIBG into a pretreated further feedstock PF which comprises synthesis gas, synthetic natural gas (SNG) and a tar oil slurry which are then preferably fed into an entrained-flow gasifier G in step (v) as pretreated further feedstock PF. In another aspect of the present invention, the tar oil slurry is fed into the at least one gasifier G (step (v)) and the synthesis gas and synthetic natural gas (SNG) are utilized in another process.

In one aspect of the present invention, the further feedstock F comprising coal is converted into a slurry before fed into an entrained-flow gasifier G in step (v) as pretreated further feedstock PF. Such a slurry can comprise a) coal and at least one liquid, or b) coal, at least one second further feedstock SF and at least one liquid, or c) coal, the first waste stream W1 (and optionally one or more of the waste streams W2, W5, W6) and at least one liquid or d) coal, the first waste stream W1 (and optionally one or more of the waste streams W2, W5, W6), at least one second further feedstock and at least one liquid. The at least one liquid is preferably selected from the group comprising or preferably consisting of water, pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, C5 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, tar oil and used oils. Such slurries are referred herein to as multicomponent slurries MS which are preferably used in case the at least one gasifier G in step (v) is an entrained-flow gasifier.

In still another aspect of the present invention, the further feedstock F comprising coal is converted into a slurry before fed into an entrained-flow gasifier G in step (v) as pretreated further feedstock PF. Such a slurry can comprise a) coal and at least one liquid, b) coal, at least one second further feedstock SF and at least one liquid, c) coal, the first waste stream W1 (and optionally one or more of the waste streams W2, W5, W6) and at least one liquid or d) coal, the first waste stream W1 (and optionally one or more of the waste streams W2, W5, W6), at least one second further feedstock and at least one liquid. The at least one liquid is preferably selected from the group comprising or preferably consisting of pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, C5 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, tar oil and used oils. The at least one second further feedstock SF is preferably selected from the group comprising or consisting of biomass, automotive shredder residue (ASR), refuse-derived fuel (RDF) and the like. Such slurries are referred herein to as multicomponent oily-slurries MOS which are preferably used in case the at least one gasifier G in step (v) is a plasma gasifier.

The further feedstock F comprising coal can also be pretreated in a fluidized-bed gasifier FLBG, preferably together with at least one second further feedstock SF selected from biomass and municipal solid waste (MSW). The resulting pretreated further feedstock PF is then fed into the at least one gasifier G in step (v) which is, for this pretreatment an entrained-flow gasifier G.

The first waste stream W1 (or the first waste stream W1 pretreated in optional step (ii)) and the further feedstock F (or the pretreated further feedstock PF formed in optional step (iv)) and, optionally one or more of the waste streams W2, W5, W6, optionally pretreated in step (ii), are then subjected to a gasification process in step (v) wherein said gasification process comprises at least one gasifier G and whereby a gas stream GS1 is formed by said gasification process.

The at least one gasifier G has at least one inlet through which a feedstock is fed into said at least one gasifier G and at least one outlet through which the gas stream GS1 is separated from said at least one gasifier G. Preferably, the at least one gasifier G has more than one inlet. Thereby, more than one feedstock can be fed into the at least one gasifier G through a separate inlet. The term "inlet” comprises openings in the at least one gasifier G such as flaps and locks but also annual gaps as part of a burner such as in twin fluid atomizers, pressure nozzles and pressure atomizers.

The gasification process of step (v) comprises at least one gasifier G. A gas stream GS1 is formed in step (v) from the first waste stream W1 (or the first waste stream W1 pretreated in optional step (ii)) and the further feedstock F (or the further feedstock PF formed by pre-treatment of further feedstock F in optional step (iv)) and, optionally one or more of the waste streams W2, W5, W6, optionally pretreated in step (ii).

The gasification process of step (v) is different from "hydrothermal gasification” described, e.g., in

WO 2024/069082 A1. Such "hydrothermal gasification” is a process in which an aqueous solution is heated above 100 °C (e.g., 350 to 450 °C) in a pressurized vessel in which, after cooling, an aqueous phase and a gas phase are formed. The gas phase formed by the "hydrothermal gasification” disclosed in WO 2024/069082 A1 is composed of 40-70 % methane, 5-20 % hydrogen and 20-40 % carbon dioxide.

In contrast, the gasification process of step (v) is a thermochemical conversion process that transforms carbonaceous materials into a combustible gas known as syngas (synthetic gas) through partial oxidation at high temperatures, typically between 800 and 1500 °C, in the presence of a controlled amount of oxygen, steam, or air. The gas formed by the gasification process in step (v) (gas stream GS1) comprises a mayor portion of carbon monoxide and hydrogen as shown in the examples further below.

The temperature in the at least one gasifier G is preferably between 800 and 1500 °C.

The further feedstock F (or pretreated further feedstock PF) is provided and subjected together with the first waste stream W1 and the at least one optional waste stream W_x, said at least one optional waste stream W_x selected from the group consisting of second waste stream W2, fifth waste stream W5 and sixth waste stream W6 to a gasification process in at least one gasifier G in step (v).

The further feedstock F (or pretreated further feedstock PF) is subjected to the gasification process in step (v) wherein said gasification process comprises at least one gasifier G and whereby said further feedstock F (or pretreated further feedstock PF) is inserted into the at least one gasifier G with the first waste stream W1 provided in step (I) (or the first waste stream W1 pretreated in optional step (ii)) and the at least one optional waste stream W_x, said at least one optional waste stream W_x selected from the group consisting of second waste stream W2, fifth waste stream W5 and sixth waste stream W6 optionally provided in step (I), optionally pretreated in step (ii). The meaning of "together” depends on the kind of optional further feedstock F (or pretreated further feedstock PF) and the type of gasifier G employed in step (v) and is explained in detail below.

Preferably, the optional second further feedstock SF is selected from the group comprising biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, C5 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, tar oil, used oils, municipal solid waste (MSW), automotive shredder residue (ASR), natural gas, industrial waste streams and mixtures thereof.

More preferably, the optional second further feedstock SF is selected from the group consisting of biomass, refuse- derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end-of-life tires, pyrolysis oils made from biomass, municipal solid waste (MSW), automotive shredder residue (ASR) and mixtures thereof.

The term "biomass” includes but is not limited to wood, wood pellets, wood chips, straw, lignocellulosic biomass, energy crops, algae, bio-based oils, and bio-based fats (preferably hydrated).

Biomass is preferably torrefied or converted by pyrolysis into a pyrolysis oil before used in step (v) as a second further feedstock SF. Municipal solid waste (MSW) is optionally pretreated by methods such as drying, shredding, sorting, inert removal and preferably used in step (v) in form of refuse-derived fuel (RDF). Shredder residues such as automotive shredder residue (ASR) is preferably pretreated by methods such as sorting, metal removal and the like before used in step (v) as second further feedstock SF. Furthermore, torrefied biomass is preferably preheated to a temperature such as 200 °C before fed into a gasifier G as a second further feedstock SF.

Liquid second further feedstock SF such as bio-based oils and pyrolysis oils are preferably pre-heated and/or pressurized before fed into the gasifier G. In case the gasifier G is a plasma gasifier, the liquid second further feedstock SF is preferably pressurized to > 1 bar(abs.), more preferably to > 2 bar(abs.) and most preferably to about 4 bar(abs.) before fed into the gasifier G. In case the gasifier G is an entrained-flow gasifier, the liquid second further feedstock SF is preferably pressurized to > 10 bar(abs.), more preferably > 20 bar(abs.) and most preferably > 40 bar(abs.) before fed into the gasifier G. Suitable means for pre-heating and/or pressurizing liquid second further feedstock SF for feeding into a gasifier are known in the art, comprise for example flaps and locks but also annual gaps as part of a burner such as in twin fluid atomizers, pressure nozzles and pressure atomizers, and can be adapted to a given second further feedstock SF and/or gasifier G type by the skilled person.

In case the gasifier G is an entrained-flow gasifier, solid second further feedstock SF such as municipal solid waste (MSW), refuse-derived fuel (RDF), wood chips, wood pellets and the like, said second further feedstock SF is preferably pressurized e.g., in a lock before fed into the gasifier G.

The at least one gasifier G is selected from entrained-flow gasifiers and plasma gasifiers. Preferably, the at least one gasifier G is a plasma gasifier. More preferably, the at least one gasifier G is a plasma fixed-bed gasifier.

An overview of gasifiers G, especially entrained-flow gasifiers G and plasma gasifiers G is for example provided in James G. Speight, Handbook of Gasification Technology, Scrivener Publishing and Wiley, 2020, chapter 8.4.2, pages 259 to 262.

The weight ratio (first waste stream W1 and the optional waste streams W2, W5, W6) : (further feedstock F) preferably ranges from 1 : 1 to 1 : 10, more preferably from 1 : 2 to 1 : 10 and most preferably from 1 : 5 to 1 : 10.

The first waste stream W1 and the further feedstock F (or the pretreated further waste stream PF formed in optional step (iv)) and at least one optional waste stream, said at least one optional waste stream selected from the group comprising or consisting of second waste stream W2, fifth waste stream W5 and sixth waste stream W6 can be fed into the gasifier G separately or be mixed before to form a waste stream mixture WM and then the mixture WM is fed into the gasifier G. The mixture WM can have a lower viscosity than the individual waste stream W1 and/or one or more of the optional waste streams W2, W5 and W6 and thereby feeding a waste stream mixture WM requires simpler equipment than feeding individual waste streams W1 and/or one or more of the optional waste streams W2, W5 and W6 into the gasifier G. Feeding a mixture WM into the gasifier G can also result in an improved atomization of the feedstock in the gasifier G compared to feeding waste stream W1 and/or one or more of the optional waste streams W2, W5 and W6 into the gasifier G. Thereby, the residence time and formation of coke inside the gasifier can be reduced.

The further feedstock F is preferably fed separately into the gasifier G, i.e., not mixed with the first waste stream W1 and/or one or more of optional waste streams W2, W5, and W6 before being fed into the gasifier G. Thereby, variations in mass flow, calorific value and other properties of the first waste stream W1 and/or one or more of the waste streams W2, W5 and W6 can be better balanced and as a result a steady operation of the gasifier G maintained. The further feedstock F is preferably fed into the gasifier G by means preferably selected from lock, screw conveyor, hopper, and flap. Most preferably, the further feedstock F comprising coal further comprises at least on second further feedstock SF selected from the group consisting of torrefied biomass, pyrolysis oil and bio-based oils wherein the pyrolysis oil can be manufactured by pyrolysis from mixed plastic waste (MPW), end of life tires (ELT) and biomass. Such feedstocks F comprising coal and at least on second further feedstock SF selected from the group consisting of torrefied biomass, pyrolysis oil and bio-based oils wherein the pyrolysis oil can be manufactured by pyrolysis from mixed plastic waste (MPW), end of life tires (ELT) and biomass have more homogenized properties such as calorific value compared to, for example, municipal solid waste (MSW) and coal.

In one aspect of the present invention, a CO2 waste stream from one or more chemical processes such as CO2 capture by absorption is also co-fed into the at least one gasifier G.

Preferably, said further feedstock F is inserted into the at least one gasifier G in step (v) with the first waste stream W1 provided in step (I) and optionally with one or more of the optional waste streams W2, W5, W6, and/or with the first waste stream W1 pretreated in step (ii) and optionally with one or more of the optional waste streams W2, W5, W6 pretreated in step (ii).

Solid fuel particles are injected in an entrained-flow gasifier G in a high-velocity stream of gas and are heated to high temperatures (typically between 800 and 1500 °C) in the presence of oxygen and/or steam. The solid particles are provided by the further feedstock F and the first waste stream W1 and/or one or more of the optional second waste stream W2, W5, W6 or the waste stream mixture WM are preferably transported in downdraft mode.

In case the at least one gasifier G in step (v) is an entrained-flow gasifier, the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and one or more of the optional waste streams W2, W5 and W6 or the waste stream mixture WM are preferably compressed up to 40 bar(abs.) or higher before fed into the at least one gasifier G.

The temperature inside the entrained-flow gasifier G preferably ranges from 800 to 1500 °C, more preferably from 1000 to 1450 °C and most preferably from 1100 to 1400 °C. The pressure inside the entrained-flow gasifier preferably ranges from 1 to 55 bar(abs.), more preferably from 5 to 50 bar(abs.) and most preferably from 20 to 45 bar(abs.).

A further feed F can support the desired constant operation conditions in the entrained-flow gasifier and a stream of synthesis gas having the desired molar ratio H2 : CO is formed.

Preferably, the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and one or more of the optional waste streams W2, W5 and W6 or the waste stream mixture WM and the further feedstock F (or the pretreated further feedstock PF) are fed into the entrained-flow gasifier via at least one burner whereby said at least one burner comprises one annular gap for the waste stream W1, and at least one of the optional waste streams W2, W5, W6,or mixed waste stream WM and a separate annular gap through which the further feedstock F (or the pretreated further feedstock PF) is fed. Steam, preferably mixed with oxygen is co-fed into the entrained-flow gasifier through a separate annular gap in said at least one burner.

Plasma gasification is a high-temperature waste treatment process that uses plasma, a gas composed of highly charged particles, to break down organic matter into a gas. In this process, the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and one or more of the optional waste streams W2, W5, W6 are fed into a plasma reactor, preferably, the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and at least one of the optional waste streams W2, W5, W6 or a waste stream mixture WM thereof are fed into the plasma reactor, where they/it are/is exposed to an electric arc or microwave radiation or at least one plasma torch, which ionizes the waste stream(s) and creates a plasma. Preferably, the plasma is generated by means of at least one plasma torch, more preferably, the plasma is generated by means of at least two plasma torches. Most preferably, the plasma gasifier comprises one to three plasma torches in the part of the gasifier where the first waste stream W1 and/or the further feedstock F (or the pretreated further feedstock PF) and one or more of the optional waste streams W2, W5, W6 or the waste stream mixture WM are fed onto the plasma gasifier and one or two plasma torches in the part of the plasma gasifier where the gas stream GS1 leaves the plasma gasifier (most preferably in arrangement which forces the gas stream GS1 to pass said one or two plasma torches). The high temperatures inside the plasma gasifier, which can reach up to about 10000 K, cause the first waste stream W1 and/or the further feedstock F (or the pretreated further feedstock PF) and, optionally one or more of the optional waste streams W2, W5, W6 or the waste stream mixture WM to vaporize and break down into the constituent components, including hydrogen, carbon monoxide, and methane.

In case the at least one gasifier G in step (v) is a plasma gasifier, the first waste stream W1, the further feedstock F (or the pretreated further feedstock PF) and optionally one or more of the optional waste streams W2, W5, W6 are preferably compressed up to 4 bar(abs.) before fed into the at least one gasifier G.

The temperature of the gas leaving the plasma gasifier is preferably in the range of 1100 to 1400 °C, most preferably around 1300 °C. The pressure of the gas leaving the plasma gasifier is preferably at least 0.7 bar(abs.) and more preferably at least 1 bar(abs.). The residence time of the reactants inside the plasma gasifier is at least 2 to 3 s. The plasma is preferably generated from a gas selected from the group comprising CO2, steam, O2, air and mixtures thereof. More preferably, the plasma is generated from a CO2, steam or a mixture of CO2 and steam.

The first waste stream W1 and one or more of the optional waste streams W2, W5, W6 or the waste stream mixture WM is/are preferably fed into the plasma gasifier through an opening separate of the opening through which the further feedstock F (or the pretreated further feedstock PF) is fed. Steam is preferably fed to the plasma gasifier through still another opening.

Optionally the process according to the present invention comprises a further step (vi) wherein said further step (vi) is selected from the group comprising or consisting of cleaning gas stream GS1 and thereby forming gas stream GS2, separating H2 and CO from gas stream GS1 and/or GS2, compressing at least one of the gas streams GS1, GS2, H2 separated from GS1, H2 separated from GS2, CO separated from GS1, CO separated from GS2, and combinations thereof. Preferably, said step (vi) comprises, in this order, cleaning gas stream GS1 and thereby forming gas stream GS2, separating H2 and CO from gas stream GS2 and compressing at least one of H2 and CO separated from gas stream GS2.

Typical impurities in the gas stream GS1 comprise chlorides, sulfur-containing organic compounds such as sulfur dioxide, trace heavy metals (e.g., as respective salts), tars/condensable hydrocarbons and particulate residues. Various chemical and/or physical methods for removal of such impurities from said gas stream GS1 such as filtration, scrubbing, condensation and ab-/adsorption are known and can be chosen and adapted according to the type and respective concentration of the impurities in said gas stream GS1 and the tolerance to such impurities in a further process FP1 . Some selected methods for removal of impurities from said gas stream GS1 will be discussed in more detail. One or more of said methods can also be implemented into the optional gas treatment unit GTU. However, this selection of methods is not limiting the scope of the present invention. Other gaseous substances such as HOI and H2S are formed and/or separated from the gas stream GS1 in the optional gas treatment unit GTU. The impurities are removed from the gas stream GS1 and a gas stream GS2 having a first molar ratio H2 : CO is obtained.

Particulate impurities can be removed from the gas stream GS1 by a cyclone and/or filters, chlorides by wet scrubbing, trace heavy metals, catalytic hydrolysis for converting sulfur-containing organic compounds to H2S and acid gas removal for extracting sulfur-containing gases such as H2S. Bulky and (fine) particles such as dust in the gas stream GS1 may also be removed with a quench in a soot water washing unit.

Particulate impurities can be optionally removed from the gas stream GS1 directly by a cyclone and/or filters after the gas stream GS1 leaves the gasifier. Hence, the removal of particles from the gas stream GS1 can be part of a gasifier and/or part of the optional gas treatment unit GTU which is fluidically connected to the at least one gasifiers G.

Fine particles can be optionally removed from the raw synthesis gas directly with filters after the gas stream GS1 leaves the at least one gasifier G. Hence, the removal of fine particles from the gas stream GS1 can be part of the at least one gasifier G and/or part of the optional gas treatment unit GTU which is fluidically connected to the at least one gasifier G.

The optional gas treatment unit GTU preferably comprises a washing unit for removing CO2 from the gas stream GS1. Most preferably, said washing unit is an "amine wash” or a "methanol” wash which uses one or more amine compounds such as alkanolamines or methanol to absorb CO2. Such washing units are known in the art and can be adapted for removal of CO2 from a gaseous stream GS1 by the skilled person.

CO and/or H2 are optionally separated from the gas stream GS1 or GS2. CO can be separated from the gas stream GS1 or GS2 in a synthesis gas separation unit which is, optionally, downstream of and fluidically connected to the at least one gasifier G or the gas treatment unit GTU. CO can be separated from gas stream GS1 or GS2 by cryogenic separation methods, commonly referred to as a "cold box” which makes use of the different boiling points of CO and H2. H2 can be separated using ^-selective membranes thorough which H2 permeates and is thereby separated from the GS1 or GS2 stream.

The gas stream GS1 has a first molar ratio H2 : CO. Optionally, the gas stream GS1 is then preferably subjected to a water-gas shift reaction in a water-gas shift unit. Thereby, the H2 content in the gas stream GS1 is increased by reacting a portion of the CO of the gas stream GS1 with water to form additional H2 and CO2 and thereby gas stream GS2 having a second molar ratio H2 : CO is formed and leaves the water-gas shift unit. Optionally, the gas stream GS2 can be subjected to a water-gas shift reaction in a water-gas shift unit instead of gas stream GS1 . The H2 content in said gas stream GS2 leaving the water-gas shift unit and having a second molar ratio H2 : CO is higher than in said gas stream GS1 leaving the at least one gasifier having a first molar ratio H2 : CO. The hydrogen content in gas stream GS1 can for example also be increased by adding hydrogen provided by another source such as hydrogen formed by electrolysis of water, preferably using electrical energy from a renewable source such as solar and/or wind energy.

The water-gas shift reaction will operate with a variety of catalysts (such as copper-zinc-aluminum catalysts and chromium or copper promoted iron-based catalysts) in the temperature range between about 200 °C and about 480 °C. The gas stream GS2 is optionally compressed, preferably, in case the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and the second waste stream W2 were converted to gas stream GS1 in a plasma gasifier. In this case, gas stream GS2 is preferably compressed to a pressure in the range 1 .5 to 4 bar(abs.).

Optionally, the gas stream GS1 and/or the gas stream GS2 are/is then subjected to a further process FP1 selected from the group comprising methanization, alcohol synthesis (preferably methanol synthesis) and Fischer-Tropsch synthesis whereby at least one first product stream PS1 is formed. The gas stream GS2 can also be used as a fuel gas Said optional further processes FP1 are briefly described below:

Optionally, the gas stream gas stream GS2 can be converted into methane by a methanation reaction. The methana- tion reaction is described by chemical reaction schemes (1) and (2):

CO + 3H₂ -> CH₄ + H₂O (1)

CO₂ + 4H₂ -> CH₄ + 2H₂O (2)

The methanation reaction and suitable methanation units are for example described in S. Rdnsch, J. Schneider, S. Matthischke, M. Schluter, M. Gdtz, J. Lefebvre, P. Prabhakaran, S. Bajohr: Review on methanation - From fundamentals to current projects; Fuel 166 (2016) 276-296 and can be selected and adapted by the skilled person.

The methanation reaction is for example a catalytic reaction using nickel on alumina catalysts, preferably a honeycomb shape catalyst, at 1 to 70 bar and 200 to 700 °C, preferably 5 to 60 bar, more preferably 10 to 45 bar and preferably 200 to 550 °C, more preferably 10 to 45 bar.

Alcohols such as methanol are another chemical product which can be manufactured from the gas stream GS2 by an optional further process FP1. The most preferred, methanol, is produced from synthesis gas by a catalytic gas phase reaction at about 5 to 10 MPa and a temperature of about 200 °C to about 300 °C using a catalyst in a low-pressure methanol process in e.g., adiabatic reactors or quasi-isothermal reactors. The catalyst is for example a mixture of copper and zinc oxides, supported on alumina. The methanol synthesis and various options thereof suitable to be combined with the production system according to the present invention are disclosed in Ullmann's Encyclopedia of Industrial Chemistry (2012), Chapter "Methanol”, p. 3 to 12.

The gas stream GS2 can also optionally be converted into hydrocarbons such as light synthetic crude oil in an optional Fischer-Tropsch (FT) reaction unit by the FT process. Such hydrocarbons are also denoted "Fischer-Tropsch hydrocarbons”. The light synthetic oil can be further converted by hydrocracking and/or isomerization to naphtha, light olefins, or diesel fuel. For production of gasoline and light olefins, the FT process is operated in a temperature range of about 330 °C to about 350 °C and a pressure of about 2.5 MPa (high-temperature FT-process), for production of waxes and/or diesel fuel, in a temperature range of about 220 °C to about 250 °C and a pressure of about 2.5 MPa to about 4.4 MPa (low-temperature FT-process). Suitable reactors for low-temperature FT-processes comprise tubular fixed-bed reactors and slurry bed reactors. Suitable reactors for high-temperature FT-processes comprise circulating fluidized-bed reactors and SAS (Sasol advanced synthol) reactors. Iron- and/or cobalt-based catalysts are used for the FT-process. The Fischer-Tropsch synthesis and various options thereof suitable to be combined with the production system according to the present invention are disclosed in Ullmann's Encyclopedia of Industrial Chemistry (2012), Chapter "Coal Liquefaction”, p. 20 to 33.

In one aspect of the present invention, the gas stream GS2 is converted into methanol for example by a method described above. Next, the methanol is converted into propene by a methanol-to-propene (MTP) synthesis which are for example disclosed in M. Khanmohammadi, Sh. Amani, A. Bagheri Garmarudi, A. Niaei "Methanol-to-propylene process: Perspective of the most important catalysts and their behavior” Chinese Journal of Catalysis 37 (2016) 325-339 (DOI: 10.1016/81872-2067(15)61031 -2). Next, the propene is used as the C3 feedstock in an acrylic acid synthesis unit and converted into crude acrylic acid as described above. Accordingly, in this aspect of the present invention, the first waste stream W1 and the further feedstock F (or the pretreated further feedstock PF) and the optional second waste stream W2 are utilized as a feedstock for the manufacture of acrylic acid.

In another aspect of the present invention, the gas stream GS1 obtainable by or formed in step (v) and/or the gas stream GS2 obtainable by or formed in optional step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 or another chemical material obtainable by or obtained by the process according to the present invention is converted to obtain a product.

The publication Prior Art Disclosure; Issue 684; paragraphs [1000] to [8005]; ISSN: 2198-4786; published: February 12, 2024, will be regarded as Reference RF1 , which is incorporated herein by reference in its entirety. Preferably, the product is a product as described in Reference RF1 ; paragraphs [1000] to [8005], Preferably, the process described herein is further a process for the production of a product.

The converting step to obtain the product preferably comprises one or more step(s) as described below and can be performed by conventional methods well known to a person skilled in the art. The converting step preferably comprises one or more step(s) selected from: recycling, preferably depolymerizing, gasifying, pyrolyzing, and/or steam cracking; and/or purifying, preferably crystallizing, (solvent) extracting, distilling, evaporating, hydrotreating, absorbing, adsorbing and/or subjecting to ion exchanger; and/or assembling, preferably foaming, synthesizing, chemical conversion, chemically transforming, polymerizing and/or compounding; and/or forming, preferably foaming, extruding and/or molding; and/or finishing, preferably coating and/or smoothing. In addition, the one or more step(s) are described in detail in Reference RF1; paragraphs [1000] to [8005],

The term "building block”, as used herein, comprises compounds, which are in a gaseous or liquid state under standard conditions of 0 °C and 0.1 MPa. Building blocks are typically used in chemical industry to form secondary products, which provide a higher structural complexity and/or higher molecular weight than the building block on which the secondary product is based. The building block is preferably selected from the group consisting of hydrogen, carbon monoxide, carbon dioxide, ethylene oxide, ethylene glycols, synthesis gas comprising a mixture of hydrogen and carbon monoxide, alkanes, alkenes, alkynes and aromatic compounds. The alkanes, alkenes, alkynes and aromatic compounds comprise in particular 1 to 12 carbon atoms, respectively.

The term "monomer”, as used herein, comprises molecules, which can react with each other to form polymer chains by polymerization. The monomer is preferably selected from the group consisting of (meth)acrylic acid, salts of (meth)acrylic acid; in particular sodium, potassium and zinc salts; (meth)acrolein and (meth)acrylates. (Methacrylates comprising 1 to 22 carbon atoms are preferred, in particular comprising 1 to 8 carbon atoms. The terms (meth)acrylic acid, (meth)acrolein or (meth)acrylate relate to acrylic acid, acrolein or acrylate and also to methacrylic acid, methacrolein or methacrylate, where applicable. Further, the monomer can be selected from hexamethylenediamine (HMD) and adipic acid.

The building block can further be an intermediate compound. The term "intermediate compound”, as used herein, comprises organic reagents, which are applied for formation of compounds with higher molecular complexity. The intermediate compound can be selected for example from the group consisting of phosgene, polyisocyanates and propylene oxide. The polyisocyanates are in particular aromatic di- and polyisocyanates, preferably toluene diisocyanate (TDI) and/or diphenylmethane diisocyanate (MDI).

The building block and the monomer and typical converting step(s) to obtain the building block or monomer are described in more detail in paragraphs [1000] to [1012] of Reference RF1.

The term "polymer A”, as used herein, comprises thermoplastic, e.g., polyamide or thermoplastic polyurethane, thermoset, e.g., polyurethane, elastomer, e.g., polybutadiene, or a copolymer or a mixture thereof and is defined in more detail in paragraphs [2001] to [2007] of Reference RF1.

The term "polymer composition A”, as used herein, comprises all compositions comprising a polymer as described above and one or more additive(s), e.g., reinforcement, colorant, modifier and/or flame retardant, and is defined in more detail in paragraph [2008] of Reference RF1.

The term "polymer product A”, as used herein, comprises any product comprising the polymer A and/or polymer composition A as described above and is defined in more detail in paragraphs [2009] and [2010] of Reference RF1.

The step(s) to obtain the polymer, preferably polymer A, polymer composition, preferably polymer composition A or polymer product, preferably polymer product A is/are described in more detail in paragraph [2011] of Reference RF1 .

The term "industrial use polymer”, as used herein, comprises rheology, polycarboxylate, alkoxylated polyalkylenamine, alkoxylated polyalkylenimine, polyether-based, dye inhibition and soil release cleaning polymers defined in more detail in paragraphs [3035] to [3044] of Reference RF1. The term "industrial use surfactant”, as used herein, comprises non-ionic, anionic and amphoteric industrial use surfactants defined in more detail in paragraphs [3008] to [3034] of Reference RF1. The term "industrial use descaling compound”, as used herein, comprises non-phosphate based builders (NPB) and phosphonates (CoP) described in more detail in paragraphs [3001] to [3005] of Reference RF1. The term "industrial use biocide”, as used herein, refers to a chemical compound that kills microorganisms or inhibits their growth or reproduction defined in more detail in paragraphs [3006] to [3007] of Reference RF1. The term "industrial use solvent”, as used herein, comprises alkyl amides, alkyl lactamides, alkyl esters, lactate esters, alkyl diester, cyclic alkyl diester, cyclic carbonates, aromatic aldehydes and aromatic esters defined in more detail in paragraphs [3045] to [3055] of Reference RF1. The term "industrial use dispersant”, as used herein, comprises anionic and non-ionic industrial use dispersants defined in more detail in paragraphs [3056] to [3058] of Reference RF1. The term "composition and/or formulation thereof” with reference to the industrial use polymers, industrial use surfactants, descaling compounds and/or industrial use biocides refers to industrial use compositions and/or institutional use products and/or fabric and home care products and/or personal care products defined in more detail in paragraph [3059] of Reference RF1. The converting step(s) to obtain the industrial use polymer, industrial use surfactant, descaling compound and/or industrial use biocide are defined in more detail in paragraph [3060] of Reference RF1. The converting steps to obtain the industrial use composition or formulation of the industrial use polymer, industrial use surfactant, descaling compound and/or industrial use biocide are defined in more detail in paragraph [3061] of Reference RF1.

The term "agrochemical composition”, as used herein, typically relates to a composition comprising an agrochemi- cally active ingredient and at least one agrochemical formulation auxiliary. Examples of agrochemical compositions, active ingredients and auxiliaries are described in more detail in Reference RF1, paragraph [4001],

The agrochemical composition may take the form of any customary formulation. The agrochemical compositions are prepared in a known manner, e.g., described by Mollet and Grubemann, Formulation technology, Wiley VCH, Weinheim, 2001; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005. The converting step(s) to obtain the agrochemically active ingredients and auxiliaries may be conducted in analogy to the production step(s) of their analogues that are based on petrochemicals or other precursors that are not gained by recycling processes. In addition, conversion to compounds mentioned in sections "Polymer” and "Cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or compositions or formulations thereof' may be performed as described in these sections as well as the respective paragraphs in Reference RF1.

The term active pharmaceutical ingredients and/or intermediates thereof, as used herein, comprises substances that provide pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body. Intermediates thereof are isolated products that are generated during a multi-step route of synthesis of an active pharmaceutical ingredient. The term pharmaceutical excipients, as used herein, comprises compounds or compound mixtures used in compositions for various pharmaceutical applications, which are not substantially pharmaceutically active on itself. Active pharmaceutical ingredients and/or intermediates thereof and pharmaceutical excipients are defined in more detail in paragraph [5001] of Reference RF1.

The converting step(s) to obtain the active pharmaceutical ingredients and/or intermediates thereof and pharmaceutical excipients may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.

The terms animal feed additives, human food additives, dietary supplements, as used herein, comprises Vitamins, Pro-Vitamins and active metabolites thereof including intermediates and precursors, especially Vitamin A, B, E, D, K and esters thereof, like acetate, propionate, palmitate esters or alcohols thereof like retinol or salts thereof and any combinations thereof; Tetraterpenes, especially isoprenoids like carotenoids and xanthophylls including their intermediates and precursors as well as mixtures and derivates thereof, especially beta carotene, Canthaxanthin, Citranax- anthin, Astaxanthin, Zeaxanthin, Lutein, Lycopene, Apo-carotenoids, and any combinations thereof; organic acids, especially formic acid, propionic acid and salts thereof, such as sodium, calcium or ammonium salts, and any combinations thereof, such as but not limited to mixtures of formic acid and sodium formiate, propionic acid and ammonium propionate, formic acid and propionic acid, formic acid and sodium formiate and propionic acid, propionic acid and sodium propionate and formic acid and sodium formiate; glycerides of carboxylic acids and short and medium chain fatty acids, conjugated linoleic acids, such as omega-6 fatty acid (C18:2) methyl ester and 1 ,2-propandiol and beverage stabilizers, such as polyvinylpyrrolidone-polymer or polyvinylimidazole/polyvinylpyrrolidone-copolymer. Animal feed additives, human food additives and dietary supplements are defined in more detail in paragraph [5002] of Reference RF1.

The converting step(s) to obtain the animal feed additives, human food additives, dietary supplements may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.

The terms aroma chemical and aroma composition as used herein, comprise a volatile organic substance with a molecular weight between 70-250 g/mol comprising a functional group with a carbon skeleton of C5-C16 carbon atoms comprising linear, branched, cyclic, for example with a ring size of C5-C18, bicyclic or tricyclic aliphatic chains and but not necessarily one or more unsaturated structural elements like double bonds, triple bonds, aromatics or heteroaromatics and preferably the one or more additional functional groups are selected from alcohol, ether, ester, ketone, aldehyde, acetal, carboxylic acid, nitrile, thiol, amine. In one aspect, the aroma chemical is a terpene-based aroma chemical, for example selected from monoterpenes and monoterpenoids, sesquiterpenes and sesquiterpe- noids, diterpenes, triterpenes or tetraterpenes. Aroma chemicals can be combined with further aroma chemicals to give an aroma composition. Aroma chemicals and aroma compositions are defined in more detail in paragraph [5003] of Reference RF1 .

The converting step(s) to obtain the aroma chemical and aroma composition may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.

The term "aqueous polymer dispersion”, as used herein, comprises aqueous composition(s) comprising dispersed polymer(s) and is defined in more detail in the section [6001] entitled "aqueous polymer dispersion” of Reference RF1. The dispersed polymer(s) may be selected from acrylic emulsion polymer(s), styrene acrylic emulsion poly- mer(s), styrene butadiene dispersion(s), aqueous dispersion(s) comprising composite particles, acrylate alkyd hybrid dispersion(s), polyurethane(s) (including UV-curable polyurethanes) and polyurethane - poly(meth)acrylate hybrid polymer(s). The term "emulsion polymer”, as used herein, comprises polymer(s) made by free-radical emulsion polymerization. Aqueous polyurethane dispersion(s) are defined in more detail in the section [6002] entitled "Polyurethane dispersions” of Reference RF1. UV-curable polyurethane(s) is/are defined in more detail in the section [6017] of Reference RF1. Polyurethane - poly(meth)acrylate hybrid polymer(s) is/are defined in more detail in the section [6016] of Reference RF1 .

The term "polymeric dispersant”, as used herein, comprises preferably polymer(s) comprising polyether side chain, in particular polycarboxylate ether polymer(s) and polycondensation product(s) defined in more detail in paragraph [6020] entitled "Polymeric dispersant” of Reference RF1.

The converting (polymerization) step(s) to obtain the aqueous polymer dispersion(s) comprising emulsion polymer(s) is/are defined in more detail in the section [6003] entitled "Emulsion polymerization” of Reference RF1.

The converting (polymerization) step(s) to obtain the aqueous polyurethane dispersion(s) is/are defined in more detail in the section [6014] entitled "Process for the preparation of aqueous polyurethane dispersions” and section [6017] entitled "Aqueous UV-curable polyurethane dispersions, their preparation and use and compositions containing them” of Reference RF1 .

Composition(s) and uses of aqueous polymer dispersion(s) and of polymeric dispersant(s) are defined in more detail in the following sections of Reference RF1 : section [6004] entitled "Uses of aqueous polymer dispersions”, section [6005] entitled "Binders for architectural and construction coatings”, section [6006] entitled "Binders for paper coating”, section [6007] entitled "Binders for fiber bonding”, section [6008] entitled "Adhesive polymers and adhesive compositions”, section [6015] entitled "Aqueous polyurethane dispersions suitable for use in coating compositions”, section [6016] entitled "Aqueous polyurethane - poly(meth)acrylate hybride polymer dispersions suitable for use in coating compositions”, section [6017] entitled "Aqueous UV-curable polyurethane dispersions, their preparation and use and compositions containing them”, section [6018] entitled "Inorganic binder compositions comprising polymeric dispersants and their use” [6019] 100% curable coating compositions.

UV-crosslinkable poly(meth)acrylate(s) and its/their uses are defined in more detail in section [6009] entitled "UV- crossli nkable poly(meth)acrylates for use in UV-curable solvent-free hotmelt adhesives and their use for making pressure-sensitive self-adhesive articles” of Reference RF1.

Polyisocyanate(s), composition(s) comprising them and their uses are defined in more detail in section [6010] entitled "Polyisocyanates” of Reference RF1.

Hyperbranched polyester polyol(s) and its/their uses are defined in more detail in section [6011] entitled "Organic solvent based hyperbranched polyester polyols suitable for use in coating compositions” of Reference RF1. The converting step(s) to obtain the hyperbranched polyester polyols is/are defined in more detail in the section [6012] entitled "Preparation of organic solvent based hyperbranched polyester polyols” of Reference RF1 . Coating compositions) comprising hyperbranched polyester polyol(s), polyisocyanate(s) and additive(s) and substrate(s) coated therewith are defined in more detail in section [6013] entitled "Organic solvent based two component coating compositions comprising hyperbranched polyester polyols and polyisocyanates” of Reference RF1.

Unsaturated polyester polyol(s), solvent-based coating composition(s) comprising said unsaturated polyester pol- yol(s) and substrate(s) for coating with said coating composition(s) are defined in more detail in section [6018] entitled "Organic solvent-based coating composition comprising unsaturated polyester polyols” of Reference RF1. 100% curable coating composition(s) is/are defined in more detail in section [6019] of Reference RF1.

Polymeric dispersant(s) for inorganic binder compositions is/are defined in more detail in section [6020] of Reference RF1. The inorganic binder composition(s) comprising the polymeric dispersants and their use are defined in more detail in section [6021] of Reference RF1. The converting step(s) to obtain the polymeric dispersant(s) are defined in more detail in section [6020] of Reference RF1. The term "inorganic binder composition” comprising the polymeric dispersant(s), as used herein, comprises preferably in particular hydraulically setting compositions and compositions comprising calcium sulfate and is defined in more detail in section [6021] of Reference RF1 entitled "Inorganic binder compositions comprising the polymeric dispersant and their use”. Specific building material formulation(s) comprising polymeric dispersant(s) or building product(s) produced by a building material formulation comprising a polymeric dispersant are disclosed in more detail in section [6021] of Reference RF1. The term "cosmetic surfactant”, as used herein, comprises non-ionic, anionic, cationic and amphoteric surfactants and is defined in more detail in paragraph [7002] of Reference RF1. The term "emollient”, as used herein, refers to a chemical compound used for protecting, moisturizing, and/or lubricating the skin and is defined in more detail in paragraph [7003] of Reference RF1. The term "wax”, as used herein, comprises pearlizers and opacifiers and is defined in more detail in paragraph [7004] of Reference RF1. The term "cosmetic polymer”, as used herein, comprises any polymer that can be used as an ingredient in a cosmetic formulation and is defined in more detail in paragraph [7005] of Reference RF1. The term "UV filter”, as used herein, refers to a chemical compound that blocks or absorbs ultraviolet light and is defined in more detail in paragraph [7006] of Reference RF1. The term "further cosmetic ingredient”, as used herein, comprises any ingredient suitable for making a cosmetic formulation. Several sources disclose cosmetically acceptable ingredients. E. g. the database Cosing on the internet pages of the European Commission discloses cosmetic ingredients and the International Cosmetic Ingredient Dictionary and Handbook, edited by the Personal Care Products Council (PCPC), discloses cosmetic ingredients. The term "composition and/or formulation thereof' with reference to the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter and/or further cosmetic ingredient refers to personal care and/or cosmetic compositions or formulations defined in more detail in paragraph [7007] of Reference RF1. The converting step(s) to obtain the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter or further cosmetic ingredient is/are defined in more detail in paragraph [7008] of Reference RF1 .

The terms "polymer B”, "polymer composition B”, "coating composition”, "other functional composition”, "foil”, "molded body”, "coating” and "coated substrate” are well known to the person skilled in the art and are defined in more detail from paragraph [8000] to [8005] of Reference RF1.

The present invention also concerns an acrylic acid plant comprising an integrated waste stream treatment facility wherein said acrylic acid plant comprises (I) an acrylic acid production unit AAPU, (ii) an acrylic acid separation unit AASU which is downstream of and fluidically connected to the acrylic acid production unit AAPU, (ill) an acrylic acid upgrading unit AAUU which is downstream of and fluidically connected to the acrylic acid separation unit AASU, and (iv) at least one gasifier G which is downstream of and preferably directly or indirectly fluidically connected to the acrylic acid separation unit AASU. This acrylic acid plant is shown schematically in Figure 1 and Figure 2. Known processes comprising at least one acrylic acid production unit AAPU, at least one acrylic acid separation unit AASU and at least one acrylic acid upgrading unit AAUU represented by Figure 1 and Figure 2 comprise SAC- and SAD- processes. An acrylic acid plant releasing at least one further waste stream selected from W4, W5 and W6 is shown in Figure 3 and Figure 4. Known processes comprising at least one acrylic acid production unit AAPU, at least one acrylic acid separation unit AASU and at least one acrylic acid upgrading unit AAUU represented by Figure 3 and Figure 4 comprise SAA-processes.

The components of the respective units AAPU, AASU, AAUU and G as disclosed above also apply to the acrylic acid plant according to the present invention.

The respective outlet for the first waste stream W1 and/or the optional second waste stream W2 of the acrylic acid separation unit AASU, preferably of the at least one absorption column comprised in the acrylic acid separation unit AASU, can be directly or indirectly fluidically connected to the respective inlet of the at least one gasifier G.

"Directly” is defined as fluidically connected by a suitable means such as a pipe. Accordingly, respective outlet for the first waste stream W1 and the optional second waste stream W2 of the acrylic acid separation unit AASU, preferably of the at least one absorption column comprised in the acrylic acid separation unit AASU is fluidically connected by a suitable means such as a pipe with the respective inlet of the at least one gasifier G. Accordingly, also the respective outlet for the optional fifth waste stream W5 and the optional sixth waste stream W6 of the acrylic acid upgrading unit AAUU is fluidically connected by a suitable means such as a pipe with the respective inlet of the at least one gasifier G.

"Indirectly” is defined as interrupted by e.g., an additional unit for pre-treating the respective feedstock, storage tank(s), transporting the first waste stream W1 and/or at least one or more of the optional waste streams W2, W5, W6 or the waste stream mixture WM from an acrylic acid production plant to the at least one gasifier G by truck or train. Accordingly, "indirectly” means for example that the respective outlet for the first waste stream W1 and the optional second waste stream W2 of the acrylic acid separation unit AASU, preferably of the at least one absorption column preferably comprised in the acrylic acid separation unit AASU, is fluidically connected to the inlet of a feedstock pre-treatment unit for first waste stream W1 and the optional second waste stream W2, which is downstream of the acrylic acid separation unit AASU, and the outlet of the feedstock pre-treatment unit is fluidically connected to the respective inlet of the at least one gasifier G which is downstream of the pre-treatment unit. Accordingly, "indirectly” also means for example that the respective outlet for the optional fifth waste stream W5 and/or the optional sixth waste stream W6 of the acrylic acid upgrading unit AAUU is fluidically connected to the inlet of a feedstock pre-treatment unit for the optional fifth waste stream W5 and/or the optional sixth waste stream W6, which is downstream of the acrylic acid upgrading unit AAUU, and the outlet of the feedstock pre-treatment unit is fluidically connected to the respective inlet of the at least one gasifier G which is downstream of the pre-treatment unit.

Various waste streams formed during production of acrylic acid from propene can be treated in the process and the acrylic acid production plant according to the present invention in a more efficient and sustainable way than utilizing conventional processes such as incineration.

The present invention is further illustrated by the following set of embodiments and combinations of embodiments resulting from the dependencies and back-references as indicated. In particular, it is noted that in each instance where a range of embodiments is mentioned, for example in the context of a term such as "The method of any of embodiments 1 to 3", every embodiment in this range is meant to be explicitly disclosed for the skilled person, i.e. the wording of this term is to be understood by the skilled person as being synonymous to "The method of any of embodiments 1, 2 and 3". Further, it is explicitly noted that the following set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and thus, suitably supports the claims of the present invention.

1. Process for utilizing at least one high calorific waste stream from an acrylic acid production plant, wherein the acrylic acid production plant comprises a) an acrylic acid production unit AAPU, b) an acrylic acid separation unit AASU, and c) an acrylic acid upgrading unit AAUU, the process comprising the steps

(v) subjecting the first waste stream W1, optionally pretreated in step (ii), and the further feedstock F and/or the pretreated further feedstock PF, and optionally, at least one of the optional waste streams W2, W5 and W6 to a gasification process at a temperature between 800 and 1500 °C, wherein said gasification process comprises at least one gasifier G and whereby a gas stream GS1 is formed by said gasification process. Process according to embodiment 1 wherein the first waste stream W1 has at least one, preferably all of the following properties: a) a calorific value in the range of 5 to 40 MJ/kg, more preferably of 7 to 35 MJ/kg and most preferably of 10 to 30 MJ/kg, b) a carbon content in the range of 30 to 80 wt.-%, more preferably 35 to 70 wt.-% and most preferably 40 to 70 wt.-%, c) a hydrogen content in the range of 2 to 8 wt.-%, more preferably 3 to 7 wt.-% and most preferably 3.5 to 6 wt.-%, d) an oxygen content in the range of 10 to 60 wt.-%, more preferably 15 to 55 wt.-% and most preferably 20 to 50 wt.-%, e) a nitrogen content in the range of 0.01 to 5 wt.-%, more preferably 0.025 to 2 wt.-% and most preferably 0.05 to 1 wt.-%, f) a sulfur content in the range of 0.025 to 5 wt.-%, more preferably 0.05 to 3 wt.-% and most preferably 0.1 to 2.5 wt.-%, wherein said first waste stream W1 is formed by an acrylic acid production process in said acrylic acid production plant. Process according to embodiment 1 or 2 wherein the acrylic acid separation unit comprises at least one absorption column or at least one condensation unit and wherein the first waste stream W1, the optional second waste stream W2 and a gaseous third waste stream W3 are separated from at least one absorption column comprised in said acrylic acid separation unit AASU. Process according to any one of embodiments 1 to 3 wherein the optional second waste stream W2 has at least one, preferably all of the following properties: a) a calorific value in the range of 1 to 40 MJ/kg, more preferably of 2 to 30 MJ/kg and most preferably of 3 to 15 MJ/kg, b) comprises less than 90 wt.-% water, more preferably less than 70 wt.-% water and most preferably less than 50 wt.-% water, c) a carbon content in the range of 1 to 30 wt.-%, more preferably 1 .5 to 25 wt.-% and most preferably 2 to 20 wt.-%, d) a hydrogen content in the range of 2 to 20 wt.-%, more preferably 3 to 18 wt.-% and most preferably 5 to 15 wt.-% and e) an oxygen content in the range of 50 to 97 wt.-%, more preferably 57 to 95.5 wt.-% and most preferably 70 to 93 wt.-%, wherein said optional second waste stream W2 is formed by an acrylic acid production process in said acrylic acid production plant.

5. Process according to any one of embodiments 1 to 4 wherein the first waste stream W1 is pretreated by a method selected from the group comprising or consisting of heating, grinding, mixing, pumping, adjusting the pH value to neutral and combinations thereof.

6. Process according to any one of embodiments 1 to 5 wherein optional the second waste stream W2 is pretreated by a method selected from the group comprising or consisting of heating, grinding, mixing, pumping, adjusting the pH value to neutral, evaporating and combinations thereof.

7. Process according to any one of embodiments 1 to 6 wherein the coal comprised in the further feedstock F is selected from the group comprising or preferably consisting of meta-anthracite, anthracite, semianthracite, low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof.

8. Process according to any one of embodiments 1 to 7 wherein the further feedstock F comprises at least 25 wt.-% coal, more preferably at least 50 wt.-% coal and up to 100 wt.-% coal.

9. Process according to any one of embodiments 1 to 8 wherein the coal is pretreated by a method selected from the group comprising or preferably consisting of milling, grinding, classification, drying, converting the coal into a slurry and combinations thereof, whereby optionally coal dust as a side product is formed.

10. Process according to embodiment 9 wherein said coal dust is co-fed into the gasifier G in step (v).

11 . Process according to any one of embodiments 1 to 10 wherein the further feedstock F further comprises at least a second further feedstock SF, the at least one second further feedstock SF selected from the group comprising or preferably consisting of biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, C5 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, tar oil, used oils, municipal solid waste (MSW), automotive shredder residue (ASR), natural gas, industrial waste streams and mixtures thereof. 12. Process according to embodiment 11 wherein the further feedstock F comprising coal is fed into the gasifier G as a slurry wherein the slurry further comprises water.

13. Process according to any one of embodiments 1 to 12 wherein the further feedstock F is pretreated in step (iv) by gasification in a fixed-bed gasifier Fl BG or a fluidized-bed gasifier FLBG whereby the further feedstock F is converted into a pretreated further feedstock PF which is selected from the group comprising or preferably consisting of raw synthesis gas, tar oil, soot, coke, ash, methane, ethane, propane, higher hydrocarbons and mixtures thereof and a gas stream GSF which gas stream GSF is optionally combined with gas stream GS1 .

14. Process according to any one of embodiments 1 to 13 wherein the acrylic acid upgrading unit comprises a method selected from the group consisting of solvent-added distillation, solvent-free distillation, azeotropic distillation, extraction combined with distillation and wherein at least one of the further waste streams fourth waste stream W4, fifth waste stream W5 and sixth waste stream W6 is/are separated from said acrylic acid upgrading unit.

15. Process according to embodiment 14 wherein the optional fifth waste stream W5 and/or the optional sixth waste stream W6 are also subjected in step (v) to said gasification process wherein said gasification process.

16. Process according to embodiments 14 or 15 wherein the optional fifth waste stream W5 has at least one, preferably all of the following properties: a) a calorific value in the range of 5 to 40 MJ/kg, more preferably of 7 to 35 MJ/kg and most preferably of 10 to 30 MJ/kg, b) carbon content in the range of 30 to 80 wt.-%, more preferably 35 to 70 wt.-% and most preferably 40 to 70 wt.-%, c) a hydrogen content in the range of 2 to 8 wt.-%, more preferably 3 to 7 wt.-% and most preferably 3.5 to 6 wt.-%, d) an oxygen content in the range of 10 to 60 wt.-%, more preferably 15 to 55 wt.-% and most preferably 20 to 50 wt.-%, e) a nitrogen content in the range of 0.01 to 5 wt.-%, more preferably 0.025 to 2 wt.-% and most preferably 0.05 to 1 wt.-%, f) a sulfur content in the range of 0.025 to 5 wt.-%, more preferably 0.05 to 3 wt.-% and most preferably 0.1 to 2.5 wt.-%, wherein said optional fifth waste stream W5 is formed by an acrylic acid production process in said acrylic acid production plant.

17. Process according to any one of embodiments 14 to 16 wherein the optional sixth waste stream W6 has at least one, preferably all of the following properties: a) a calorific value in the range of 1 to 40 MJ/kg, more preferably of 2 to 30 MJ/kg and most preferably of 3 to 15 MJ/kg, b) comprises less than 90 wt.-% water, more preferably less than 70 wt.-% water and most preferably less than 50 wt.-% water, c) a carbon content in the range of 1 to 30 wt.-%, more preferably 1 .5 to 25 wt.-% and most preferably 2 to 20 wt.-%, d) a hydrogen content in the range of 2 to 20 wt.-%, more preferably 3 to 18 wt.-% and most preferably 5 to 15 wt.-% and e) an oxygen content in the range of 50 to 97 wt.-%, more preferably 57 to 95.5 wt.-% and most preferably 70 to 93 wt.-%, wherein said optional sixth waste stream W6 is formed by an acrylic acid production process in said acrylic acid production plant.

18. Process according to any one of embodiments 1 to 17 wherein said at least one gasifier G is selected from plasma gasifier and entrained-flow gasifier.

19. Process according to any one of embodiments 1 to 18 wherein the at least one gasifier G is a fixed-bed plasma gasifier.

20. Process according to any one of embodiments 1 to 19 wherein said further feedstock F is inserted into the at least one gasifier G in step (v) with the first waste stream W1 provided in step (I) and optionally with one or more of the optional waste streams W2, W5, W6, and/or with the first waste stream W1 pretreated in step (ii) and optionally with one or more of the optional waste streams W2, W5, W6 pretreated in step (ii).

21 . Process according to any one of embodiments 1 or 20 wherein the weight ratio (first waste stream W1 and the optional waste streams W2, W5, W6) : (further feedstock F) preferably ranges from 1 : 1 to 1 : 10, more preferably from 1 : 2 to 1 : 10 and most preferably from 1 : 5 to 1 : 10.

22. Process according to any one of embodiments 1 to 21 wherein the gas stream GS1 formed in step (v) comprises CO, CO2 and H2.

23. Process according to embodiment 22 wherein the molar ratio CO : H2 in the gas stream GS1 formed in step (v) preferably ranges from 0.7 : 1 to 1 : 0.7, more preferably from 0.8 : 1 to 1 : 0.8 and most preferably is about 1 : 1.

24. Process according to any one of embodiments 1 to 23 wherein the gas stream GS1 formed in step (v) preferably comprises < 15 Vol.-% CO2, more preferably < 10 Vol.-% CO2 and most preferably < 8 Vol.-% CO2.

25. Process according to any one of embodiments 21 to 24 wherein the process comprises a further step (vi) said further step (vi) selected from the group comprising or consisting of cleaning gas stream GS1 and thereby forming gas stream GS2, separating H2 and CO from gas stream GS1 and/or GS2, compressing at least one of the gas streams GS1, GS2, H2 separated from GS1, H2 separated from GS2, CO separated from GS1, CO separated from GS2, and combinations thereof.

26. Process according to embodiment 25 wherein step (vi) comprises, in this order, cleaning gas stream GS1 and thereby forming gas stream GS2, separating H2 and CO from gas stream GS2 and compressing at least one of H2 and CO separated from gas stream GS2.

27. Process according to any one of embodiments 1 to 26 wherein steam is co-fed into the at least one gasifier G in step (v). 28. Process according to embodiment 27 wherein the weight ratio "(first waste stream W1 and further feedstock F) : steam” preferably ranges from 1 : 1 to 10 : 1, more preferably from 2 : 1 to 10 : 1 and most preferably from 5 : 1 to 10 : 1 or higher.

29. Process according to any one of embodiments 1 to 28 wherein the at least one gasifier G is an entrained-flow gasifier and wherein oxygen and steam are co-fed in step (v) into the gasifier G.

30. Process according to any one of embodiments 1 to 29 wherein the at least one gasifier G is a plasma gasifier utilizing a plasma and wherein said plasma is formed from one or more sources selected from the group comprising or consisting of H2O, CO2, O2 and air.

31 . Process according to embodiment 30 wherein the plasma is formed by a method selected from the group comprising or consisting of microwave radiation, electrical arc and plasma torch.

32. Process according to embodiment 30 or 31 wherein the plasma is formed by at least one plasma torch.

33. Process according to any one of embodiments 1 to 32 wherein a third waste stream W3 is separated from the acrylic acid separation unit, wherein said waste stream W3 is a gaseous waste stream and wherein said third waste stream W3 is formed by an acrylic acid production process in said acrylic acid production plant.

34. Process according to embodiment 33 wherein the third waste stream W3 preferably comprises 0 to 6 wt.-% carbon, 0 to 12 wt.-% hydrogen, 0 to 95 wt.-% oxygen, 0 to 95 wt.-% nitrogen and 0 to 4 wt.-% sulfur, wherein the sum of carbon, hydrogen, oxygen, nitrogen and sulfur is at least 95 wt.-%.

35. Process according to any one of embodiments 1 to 34 wherein an optional fourth waste stream W4 is separated from the acrylic acid upgrading unit, wherein said waste stream W4 is a gaseous waste stream and wherein said optional fourth waste stream W4 is formed by an acrylic acid production process in said acrylic acid production plant.

36. Process according to embodiment 35 wherein the optional fourth waste stream W4 preferably comprises 0 to 6 wt.-% carbon, 0 to 12 wt.-% hydrogen, 0 to 95 wt.-% oxygen, 0 to 95 wt.-% nitrogen and 0 to 4 wt.-% sulfur, wherein the sum of carbon, hydrogen, oxygen, nitrogen and sulfur is at least 95 wt.-%.

37. Process according to embodiment 35 or 36 wherein the third waste stream W3 and optionally the fourth waste stream W4 is/are treated by at least one method selected from incineration in an incineration unit I U, regenerative thermal oxidation (RTO) and catalytic oxidation.

38. Process according to any one of embodiments 1 to 37 wherein at least one of the gas streams selected from the group consisting of GS1 formed in step (v) and/or gas stream GS2 formed in optional step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 is subjected to a further process FP1 selected from the group comprising or preferably consisting of, methanization, alcohol synthesis (preferably methanol synthesis), and Fischer-Tropsch synthesis, whereby at least one first product stream PS1 is formed.

39. Process according to any one of embodiments 1 to 38, comprising the step:

- converting the gas stream GS1 obtainable by or formed in step (v) and/or the gas stream GS2 obtainable by or formed in step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 or another chemical material obtainable by or obtained by the process according to any one of embodiments 1 to 38 to obtain a product.

40. Process according to embodiment 39, wherein the product is selected from:

I) building block or monomer; or ii) polymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; or ill) cleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; or iv) agrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; or v) active pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; or vi) aqueous polymer dispersion, preferably polyurethane or polyurethane - poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coatings, UV-curable acrylic polymer for hot melts and coatings polyisocyanates, hyperbranched polyester polyol, polymeric dispersant for inorganic binder compositions, unsaturated polyester polyol or 100% curable composition; or vii) cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or composition or formulation thereof; or viii) polymer B, polymer composition B, coating composition, other functional composition, foil, molded body, coating or coated substrate.

41 . Process according to embodiments 39 or 40, wherein the content of the gas stream GS1 obtainable by or formed in step (v) and/or the gas stream GS2 obtainable by or formed in optional step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 or another chemical material obtainable by or obtained by the process according to any one of embodiments 1 to 38 in the product is 1 weight-% or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and/or wherein the content of the gas stream GS1 obtainable by or formed in step (v) and/or the gas stream GS2 obtainable by or formed in optional step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 or another chemical material obtainable by or obtained by the process according to any one of embodiments 1 to 38 in the product is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably wherein the content is determined based on identity preservation and/or segregation and/or mass balance and/or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard. 42. Acrylic acid plant comprising an integrated waste stream treatment facility wherein said acrylic acid plant comprises a) an acrylic acid production unit AAPU, b) an acrylic acid separation unit AASU downstream and fluidically connected to the acrylic acid production unit AAPU, said acrylic acid separation unit AASU purging a first waste stream W1, c) an acrylic acid upgrading unit AAUU, downstream and fluidically connected to the acrylic acid separation unit AASU, d) at least one gasifier G, downstream of and directly or indirectly fluidically connected to the acrylic acid separation unit AASU and optionally also downstream of and directly or indirectly fluidically connected to the acrylic acid upgrading unit AAUU, wherein said at least one gasifier G is a plasma gasifier or an en- trained-flow gasifier.

43. Acrylic acid plant according to embodiment 42 wherein the at least one gasifier G is directly or indirectly fluidically connected to the first waste stream W1 of the acrylic acid separation unit AASU.

44. Acrylic acid plant according to embodiment 42 or 43 wherein the acrylic acid upgrading unit AAUU comprises a method selected from the group consisting of crystallization and distillation.

45. Acrylic acid plant according to embodiment 42 or 43 wherein the acrylic acid upgrading unit AAUU comprises a method selected from the group consisting of solvent-added distillation, solvent-free distillation, azeotropic distillation, reactive distillation, extraction, and combinations thereof wherein at least one of waste streams W5 and W6 are separated from said acrylic acid upgrading unit AAUU.

46. Acrylic acid plant according to embodiments 42, 43 and 45 wherein the at least one gasifier G is furthermore directly or indirectly fluidically connected to at least one of waste streams W5 and W6.

47. Use of an acrylic acid plant according to any one of embodiments 42 to 46 for the process according to any one of embodiments 1 to 37.

48. A computer program comprising instructions which, when the program is executed by the plant according to any one of embodiments 42 to 46, cause the plant to perform the process according to any one of embodiments 1 to 37.

The invention will be further explained by the following non-limiting examples.

The examples are divided into four applied gasification technologies:

1. entrained-flow gasification

2. combination of a fluidized-bed gasification and entrained-flow gasification (entrained-flow gasifier G2 downstream of the fluidized-bed gasifier G1; coal as further feedstock F pretreated in fluidized-bed gasifier G1, then pretreated further feedstock F + waste stream of acrylic acid production process as combined feedstock in entrained-flow gasifier G2) 3. plasma gasification

4. combination of fixed-bed gasification and entrained-flow gasification (entrained-flow gasifier G2 downstream of the fixed-bed gasifier G1; coal as further feedstock F pretreated in fixed-bed gasifier G1, then pretreated further feedstock F + waste stream of acrylic acid production process as combined feedstock in entrained-flow gasifier G2)

Table 1 : for the simulations, two different coal ranks ("meta terms” according to ASTM D388-23) were used. coal type Index C (wt.-%) H (wt.-%) O (wt.-%) N (wt.-%) S (wt.-%) ash (wt.-%) high rank H 80 8 5 0 0 7 coal low rank L 50 6 25 2 3 14 coal

Table 2: for the simulations, three different waste streams W were used and marked with an index.

Index C (wt.-%) H (wt.-%) O (wt.-%) N (wt.-%) S (wt.-%) ash (wt.-%)

W5¹ 51 5 44 0 0 0

W1a² 24 8 67.9 0 0.1 0

W1b³ 61.6 5 31.4 0.6 1.4 0

¹: waste stream W5 from a SAA acrylic acid production process shown in figures 3 and 4, W5 separated from the acrylic acid upgrading unit AAUU.

²: waste stream W1 from a SAC acrylic acid production process shown in figures 1 and 2, W1 separated from the acrylic acid separation unit AASU.

³: waste stream W1 from a SAD acrylic acid production process shown in figures 1 and 2, W1 separated from the acrylic acid separation unit AASU.

General description for entrained-flow gasification

A feed stream of coal was sent into an entrained-flow gasifier in combination with the waste streams and gasification agents (oxygen and steam), to reach a synthesis gas temperature at the gasifier outlet of around 1350 °C and a pressure of 45 bar. The resulting raw synthesis gas (gas stream GS1), comprising CO, H2O, CO2, H2 and optionally ash and/or dust, which left the gasifier G via the gas outlet of the gasifier G was washed and dried to reduce the amount of water and ash comprised therein. Slag was removed from the gasifier G directly. After washing and drying, the gas stream GS1 had a temperature of 25 °C and was subjected to acid gas removal, by amine scrubbing, to separate acids such as CO2. The composition and normalized mass flow of the resulting gas stream GS2 is given in the tables below.

I: Coal feed (further feedstock F) in gasifier G in kg / (kg synthesis gas (H2+CO)) at 25 °C and 60 bar

II: acrylic acid production waste stream feed in gasifier G in kg / (kg synthesis gas (H2+CO)) at 100 °C and 50 bar III: O2 feed in gasifier G in kg / (kg synthesis gas (H2+CO)) at 25 °C and 47 bar

IV: steam feed in gasifier G in kg / (kg synthesis gas (H2+CO)) at 400 °C and 70 bar V: produced CO2 in gasifier G in kg / (kg synthesis gas (H2+CO)) VI: molar ratio H2 : CO in mol H2 : mol CO Table 3: results from gasification in an entrained-flow gasifier G.

(coal type / waste stream index) I II III IV V VI

Example 1.1 (H / W5) 0.69 0.03 1.00 0.17 0.49 0.55

Example 1.2 (L / W5) 1.84 0.07 1.71 0.46 1.62 0.61

Example 1.3 (H / W1 a) 0.70 0.07 1.02 0.17 0.53 0.57

Example 1.4 (L / W1 a) 1.88 0.19 1.77 0.47 1.72 0.63

Example 1.5 (H / W1 b) 0.66 0.02 0.93 0.17 0.43 0.57

Example 1.6 (L / W1 b) 1.69 0.06 1.51 0.42 1.39 0.62

General description for combination of a fluidized-bed gasification and entrained-flow gasification

A feed stream of coal was sent into a fluidized-bed gasifier (= first gasifier G1) in combination with gasification agents (oxygen and steam), to reach a synthesis gas temperature at the gasifier outlet of around 850 °C and a pressure of 4 bar. The resulting gas (stream PF) was afterwards sent to an entrained-flow gasifier (=second gasifier G2) together with additional oxygen and the acrylic acid waste stream to produce a raw synthesis gas. The resulting raw synthesis gas (gas stream GS1), comprising CO, H2O, CO2, H2 and optionally ash and/or dust, which left the second gasifier G2 via the gas outlet of the gasifier G2 was washed and dried to reduce the amount of water and ash comprised therein. Ash was also removed from the gasifier G2 directly. After washing and drying, the gas stream GS1 had a temperature of 25 °C and was subjected to acid gas removal, by amine scrubbing, to separate acids such as CO2. The composition and normalized mass flow of the resulting gas stream GS2 is given in the tables below.

I: coal feed in gasifier G1 in kg I (kg synthesis gas (H2+CO)) at 25 °C and 5 bar

II: acrylic acid production waste stream feed in gasifier G2 in kg I (kg synthesis gas (H2-CO)) at 100 °C and 15 bar

III: O2 feed in gasifier G1 in kg I (kg synthesis gas (H2+CO)) at 25 °C and 15 bar

IV: O2 feed in gasifier G2 in kg I (kg synthesis gas (H2+CO)) at 25 °C and 15 bar

V: steam feed in gasifier G1 in kg I (kg synthesis gas (H2+CO)) at 180 °C and 5.4 bar

VI: produced CO2 in both gasifiers G1 and G2 combined in kg I (kg synthesis gas (H2+CO))

VII: molar ratio H2 : CO ratio in mol H2 : mol CO

Table 4: results from combined gasification in a fluidized-bed gasifier G1 and an entrained-flow gasifier G2.

(coal type / waste stream inI II III IV V VI VII dex)

Example 2.1 (H / W5) 0.69 0.03 0.86 0.13 0.17 0.49 0.55

Example 2.2 (L / W5) 1.84 0.07 1.42 0.28 0.46 1.61 0.61

Example 2.3 (H / W1 b) 0.66 0.02 0.83 0.11 0.17 0.44 0.56

Example 2.4 (L / W1 b) 1.69 0.06 1.30 0.20 0.42 1.39 0.62

General description for plasma gasification

A feed stream of coal was sent together with the acrylic acid production waste stream into a plasma gasifier G in combination with steam as plasma source, to reach a synthesis gas (gas stream GS1) temperature at the gasifier G outlet of around 1350 °C and a pressure of 1 bar. The resulting raw synthesis gas (gas stream GS1), comprising CO, H2O, CO2, H2 and optionally ash and/or dust, which left the gasifier G via the gas outlet of the gasifier G was washed and dried to reduce the amount of water and ash comprised therein. Slag was also removed from the plasma gasifier G directly. After washing and drying, the gas stream GS1 had a temperature of 25 °C and was subjected to acid gas removal, by amine scrubbing, to separate acids such as CO2. The composition and normalized mass flow of the resulting gas stream GS2 is given in the tables below.

I: coal feed in plasma gasifier G in kg / (kg synthesis gas (H2+CO)) at 25 °C and 5 bar

II: acrylic acid production waste stream feed in plasma gasifier G in kg / (kg synthesis gas (H2+CO)) at 100 °C and

15 bar

III: steam feed in in plasma gasifier G in kg / (kg synthesis gas (H2+CO)) at 180 °C and 5.4 bar

IV: electricity needed for the plasma formation in kWh I (kg synthesis gas (H2+CO))

V: produced CO2 in the plasma gasifier G in kg / (kg synthesis gas (H2+CO))

VI: molar ratio H2 : CO in mol H2 : mol CO

Table 5: (coal type / waste stream index) I II III IV V VI

Example 3.1 (H / W5) 0.48 0.02 0.54 6.29 0.01 1.58

Example 3.2 (L / W5) 0.86 0.03 0.43 6.86 0.09 1.46

Example 3.3 (H / W1a) 0.47 0.05 0.53 6.23 0.02 1.56

Example 3.4 (H / W1a) 0.83 0.08 0.21 6.44 0.02 1.33

Example 3.5 (H / W1b) 0.47 0.02 0.56 6.08 0.02 1.57

Example 3.6 (L / W1b) 0.83 0.03 0.31 6.24 0.04 1.38

General description for fixed-bed gasification combined with entrained-flow gasification

A feed stream of coal was sent together into a fixed-bed gasifier G1 in combination with steam and oxygen, to reach a synthesis gas temperature at the gasifier outlet of around 500 °C. The resulting raw synthesis gas (stream PF), comprising CO, H2O, CO2, H2, CH4 and higher hydrocarbons, which left the gasifier G1 via the gas outlet of the gasifier G1 was washed and dried to reduce the amount of water and ash comprised therein and sent to a water gas shift reactor in order to form synthesis gas, CO2 and CH4. The resulting tar oil slurry from the fixed-bed gasifier G1 was sent to an entrained-flow gasifier G2 and converted with oxygen and the acrylic acid production plant waste stream into a raw synthesis gas (gas stream GS1) at 1350 °C. After the synthesis gas trace contaminant removal, the resulting gas was also sent to the water gas shift in order to produce synthesis gas (gas stream GS2) with a desired molar ratio H2 : CO.

I: coal feed in fixed-bed gasifier G1 in kg I (kg synthesis gas (H2+CO)) at 25 °C and 50 bar

II: acrylic acid production waste stream feed in entrained-flow gasifier G2 in kg I (kg synthesis gas (H2+CO)) at 100 °C and 50 bar

III: O2 feed in fixed-bed gasifier G1 in kg I (kg synthesis gas (H2+CO)) at 25 °C and 47 bar IV: O2 feed in entrained-flow gasifier G2 in kg I (kg synthesis gas (H2-CO)) at 25 °C and 47 bar V: steam feed in fixed-bed gasifier G1 in kg / (kg synthesis gas (H2+CO)) at 400 °C and 70 bar VI: CO2 produced in gasifiers G1 and G2 combined in kg I (kg synthesis gas (H2+CO)) VII: molar ratio H2 : CO of gas stream GS2 (after water-gas shift) in mol H2 : mol CO VIII: CH4 produced from gas stream GS1 (after water-gas shift) in kg I (kg synthesis gas (H2+CO)) Table 6:

(coal type / waste stream I II III IV V VI VII VIII index)

Example 4.1 (H / W5) 1.03 0.04 0.90 0.04 0.77 0.81 0.34 0.27

Example 4.2 (L / W5) 5.00 0.19 2.65 0.25 10.01 5.02 0.66 0.84

Example 4.3 (H / W1 a) 1.05 0.10 0.92 0.06 0.79 0.87 0.36 0.28

Example 4.4 (L / W1 a) 5.52 0.55 2.93 0.35 11.03 5.80 0.90 0.93

Example 4.5 (H / W1b) 1.01 0.04 0.89 0.01 0.80 0.79 0.41 0.27

Example 4.6 (L / W1b) 3.19 0.12 1.69 0.02 6.68 3.20 1.18 0.54

Claims

(v) subjecting the first waste stream W1, optionally pretreated in step (ii), and the further feedstock F and/or the pretreated further feedstock PF, and optionally, at least one of the optional waste streams W2, W5 and W6 to a gasification process at a temperature between 800 and 1500 °C, wherein said gasification process comprises at least one gasifier G and whereby a gas stream GS1 is formed by said gasification process.

2. Process according to claim 1 wherein the first waste stream W1 has at least one, preferably all of the following properties: a) a calorific value in the range of 5 to 40 M J/kg, more preferably of 7 to 35 M J/kg and most preferably of 10 to 30 M J/kg, b) a carbon content in the range of 30 to 80 wt.-%, more preferably 35 to 70 wt.-% and most preferably 40 to 70 wt.-%, c) a hydrogen content in the range of 2 to 8 wt.-%, more preferably 3 to 7 wt.-% and most preferably 3.5 to 6 wt.-%, d) an oxygen content in the range of 10 to 60 wt.-%, more preferably 15 to 55 wt.-% and most preferably 20 to 50 wt.-%, e) a nitrogen content in the range of 0.01 to 5 wt.-%, more preferably 0.025 to 2 wt.-% and most preferably 0.05 to 1 wt.-%, f) a sulfur content in the range of 0.025 to 5 wt.-%, more preferably 0.05 to 3 wt.-% and most preferably 0.1 to 2.5 wt.-%, wherein said first waste stream W1 is formed by an acrylic acid production process in said acrylic acid production plant.

3. Process according to claim 1 or 2 wherein the coal comprised in the further feedstock F is selected from the group comprising or preferably consisting of meta-anthracite, anthracite, semianthracite, low volatile bituminous coal, medium volatile bituminous coal, high volatile A bituminous coal, high volatile B bituminous coal, high volatile C bituminous coal, subbituminous A coal, subbituminous B coal, subbituminous C coal, lignite A, lignite B and mixtures thereof.

4. Process according to any one of claims 1 to 3 wherein the further feedstock F comprises at least 25 wt.-% coal, more preferably at least 50 wt.-% coal and up to 100 wt.-% coal.

5. Process according to any one of claims 1 to 4 wherein the acrylic acid separation unit comprises at least one absorption column or at least one condensation unit and wherein the first waste stream W1 and the optional second waste streams W2 and W3 are separated from said at least one absorption column or said at least one condensation unit.

6. Process according to any one of claims 1 to 5 wherein the first waste stream W1 is pretreated by a method selected from the group comprising or consisting of heating, grinding, mixing, pumping and combinations thereof.

7. Process according to any one of claims 1 to 6 wherein said at least one gasifier G is selected from plasma gasifier and entrained-flow gasifier.

8. Process according to any one of claims 1 to 7 wherein said further feedstock F is inserted into the at least one gasifier G in step (v) with the first waste stream W1 provided in step (I) and optionally with one or more of the optional waste streams W2, W5, W6, and/or with the first waste stream W1 pretreated in step (ii) and optionally with one or more of the optional waste streams W2, W5, W6 pretreated in step (ii).

9. Process according to any one of claims 1 to 8 wherein the further feedstock F comprises a second further feedstock SF which is selected from the group comprising biomass, refuse-derived fuel (RDF), pyrolysis oils made from plastic waste, pyrolysis oils made from end of life tires, pyrolysis oils made from biomass, heating oils, vacuum residues, preferably vacuum distillation residues, crude oil residues, heavy crude oils, extra heavy crude oils, tar sand bitumen, visbreaker bottom residues, deasphalter bottom residues, C5 asphalthene fraction, high viscous residues, fuel oils, pyrolysis gasolines, waste oils, tar oil, used oils, municipal solid waste (MSW), automotive shredder residue (ASR), natural gas, industrial waste streams and mixtures thereof.

10. Process according to claims 8 or 9 wherein the weight ratio (first waste stream W1 and the optional waste streams W2, W5, W6) : (further feedstock F) preferably ranges from 1 : 1 to 1 : 10, more preferably from 1 : 2 to 1 : 10 and most preferably from 1 : 5 to 1 : 10.

11 . Process according to any one of claims 1 to 10 wherein the process comprises a further step (vi) said further step (vi) selected from the group comprising or consisting of cleaning, separating H2 and CO from each other, compressing and combinations thereof.

12. Process according to any one of claims 1 to 11 wherein steam is co-fed into the at least one gasifier G in step (v).

13. Process according to claim 12 wherein the weight ratio "(first waste stream W1 and further feedstock F) : steam” preferably ranges from 1 : 1 to 10 : 1, more preferably from 2 : 1 to 10 : 1 and most preferably from 5 : 1 to 10 : 1 or higher.

14. Process according to any one of claims 1 to 13, comprising the step:

- converting the gas stream GS1 obtainable by or formed in step (v) and/or the gas stream GS2 obtainable by or formed in optional step (vi) and/or H2 separated from gas stream GS1 or GS2 and/or CO separated from gas stream GS1 or GS2 or another chemical material obtainable by or obtained by the process according to any one of claims 1 to 12 to obtain a product.

15. Acrylic acid plant comprising an integrated waste stream treatment facility wherein said acrylic acid plant comprises a) an acrylic acid production unit AAPU, b) an acrylic acid separation unit AASU downstream and fluidically connected to the acrylic acid production unit AAPU, said acrylic acid separation unit AASU purging a first waste stream W1, c) an acrylic acid upgrading unit AAUU, downstream and fluidically connected to the acrylic acid separation unit AASU, d) at least one gasifier G, downstream of and directly or indirectly fluidically connected to the acrylic acid separation unit AASU and optionally also downstream of and directly or indirectly fluidically connected to the acrylic acid upgrading unit AAUU, wherein said at least one gasifier G is a plasma gasifier or an entrained-flow gasifier.