HUP0700508A2 - Appliance for carbon catena development and process for neutralisation of dangerous wastes - Google Patents

Description

P 07 00508 wall O o£c (VII. 2008)

Representative: Tibor Rónaszéki, Budapest, HU

PUBLICATION

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Catalytic pyrolysis device and method for producing the structure of the boundary body of the catalytic pyrolysis device

The invention relates to a catalytic pyrolysis device primarily for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, which comprises a boundary body enclosing a reaction space and an active material coating at least partially covering the inner side of the boundary body, where the boundary body is a ceramic material with a solid core and a porous shell with cavities suitable for receiving particles of the active material coating on at least the boundary surface of the core facing the reaction space, and the active material coating has a nickel base containing magnesium.

The invention also relates to a method for producing a structure of a boundary body of a catalytic pyrolysis device suitable primarily for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, during which a core material is formed, the formed core is subjected to heat treatment, then coated with a shell former, then subjected to another heat treatment, then the shell is coated with an active material, and finally subjected to further heat treatment.

More specifically, the invention is a reductive pyrolysis-catalytic device with a specific design, a low active material content, but a high reactivity and an efficient operation despite the low active material content, with hydrogenation, pyrolysis, extended primary and secondary combustion and post-combustion flow, and a method for its implementation, the basis of which is the combustion device known as "NoCo", but essentially known from the patent specifications with registration number HU 206.148, registration number HU 225.373 and publication number WO 99/54660.

The essence of the known device is that the device suitable for incinerating hazardous materials and waste to be destroyed has a specific geometric shape, e.g. composed of suitable cylindrical, shell parts or ring-shaped elements.

10,584

-2 has a boundary body enclosing the reaction space, which is made of a porous, usually ceramic material, and which is saturated with the required active material. The selectivity and required activity of the pyrolysis catalytic device thus prepared can be influenced by the appropriate choice of the material composition of the boundary body, and by changing the accelerator(s) or promoter(s) added to the active material component covering it, thus setting the required optimal effect.

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Based on the literature and our practical experience, the activity of a pyrolysis catalytic device in a heterogeneous catalytic process can be enhanced by using a suitable active material applied to a carrier of suitable material quality, by creating a large specific surface area of the carrier, by increasing the surface concentration of the active material, by selecting the appropriate amount of active materials, by promoting or using accelerators, and by using suitable high- and high-temperature-resistant metal oxides, typically titanium-alloy materials, in a layered, sandwich or single-layer coating.

In Hungary, for the air-cyclic decomposition of mixed hydrocarbons with a maximum of 6 carbon atoms, a process was previously used, which involved a Ni- or Ni-Mg double salt applied by immersion to a highly porous support based on mullite - i.e. aluminum-silicate, 3 AI2O3.2 S1O2 - 2 AI2O3.S1O2 mixed crystal series - and activated by heating. The basic principle did not change in the later years, but was refined, and the range of hydrocarbons to be processed was expanded with higher homologues. The currently known similar pyrolysis-catalytic equipment generally contains 12-14 t% Ni-based active material.

However, the disadvantage of the known solutions is that the application of active material to the appropriate material quality requires a highly porous substrate to achieve a high surface active material concentration. A highly porous substrate, however, means the use of a large amount of active material. However, due to the high price of the active materials, the price of the finished pyrolysis catalytic device also increases significantly.

However, Hungary is a country poor in precious metals and semi-precious metals that can be used as active materials for catalysts, but it has very favorable conditions for certain types of ceramic materials, primarily corundum-based and containing corundum.

- 3 for the production of refractory ceramics. Thus, one condition is present for the production of pyrolysis-catalytic equipment representing a high specific value and containing a large share of intellectual work, but the other condition - the availability of the active material in sufficient quantity and at a favorable price - is missing for such equipment to be produced at an acceptable price.

With the solution and method according to the invention, our goal was to eliminate the shortcomings of the known catalytic pyrolysis equipment, which is primarily suitable for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, and to create a highly active version in which increased reaction activity, and thus the essentially complete destruction or disposal of flue gases containing undesirable components, can be achieved with a minimal active material content.

The basis of the inventive idea was that, based on our investigations, we came to the conclusion that the most suitable core of the aforementioned surface layer is protoenstatite ceramic stabilized with a solid sintered glassy phase, where even the material quality of the glassy phase is important, because in contact with the surface porous layer, it affects the cladding layer through the transition layer, and thus affects the resulting electronic structure modifications. While the surface layer containing metal salt-silicate doped with alpha-corundum has the most favorable interaction with the novel internal and external carrier material composition. That is, the structure and material of the boundary body, the active material and the complex unit of the modifying components added to it set the final parameters of the device.

Starting from this, the solution according to the invention was led by the realization that if the boundary body surrounding the reaction space of the device is made of a ceramic with a body shape different from the usual one and a special material composition, and the ceramic boundary body is surrounded by a monolithic metal material with high heat resistance or a ceramic alloy with metallic properties, and thus a novel sandwich structure-like layering is created, then the chemical stability of the internal operation of the reactor space and the stability of the external infrared effect can be achieved. Furthermore, if the active material coating the surface layer of the boundary body is associated with suitably selected additives that increase efficiency and accelerate, then the speed and selectivity of the expected reactions can be shifted in the desired direction even if a small active material coating is used, and thus the task can be solved.

-4A In accordance with the aim set forth, the catalytic pyrolysis device according to the invention is primarily intended for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, - which comprises a boundary body enclosing a reaction space and an active material coating at least partially covering the inner side of the boundary body, where the boundary body is a ceramic material with a solid core and a porous structure shell having cavities suitable for receiving particles of the active material coating on at least the boundary surface of the core facing the reaction space, and the active material coating has a magnesium-containing nickel base, - it is designed in such a way that the core of the boundary body is made of protoenstatite stabilized with a glassy phase and sintered to a compact state, and the porous shell at least partially covering the core is made of magnesium silicate doped with alpha corundum with a thickness of 0.6-1.1 mm, and the active material coating located on the porous structure outer surface of the shell is It contains NiMg oxide produced by heat treatment from Ni-Mg double salt and optionally Ni-Si components.

A further feature of the device according to the invention may be that the limiting body has a cylindrical shell section and a dome section, as well as an inlet and an outlet, and is further supplemented with a blocking element.

In a possible embodiment of the device, the longitudinal cross-sectional image of the interface of the solid core in contact with the porous shell is wavy in the shape of a sinusoidal curve, where the ratio of the average diameter and height of each wave is between 0.3 and 1. The external average diameter of the interface of the solid core in contact with the porous shell is between 10 and 1000 mm.

In another embodiment of the invention, the active material coating formed from the Ni-Mg double salt contains 0.64-0.76 mol% nickel, 0.23-0.28 mol% magnesium and optionally Ni-Si, and optionally the active material coating contains 0.48-0.65 t% titanium dioxide, 0.16-0.38 t% gallium dioxide and 0.05-0.25 t% zinc dioxide as efficiency-enhancing and accelerating components, based on the weight of the active material calculated in the form of the nitrate hexahydrate salt.

In accordance with the set objective, the method according to the invention is primarily for the neutralization of hazardous combustion products and waste materials, the destruction of flue gases and the utilization of complex carbon chains, and the construction of a catalytic pyrolysis device.

-5, - during which a core material is shaped, the shaped core is subjected to heat treatment, then coated with a shell former, then subjected to another heat treatment, then the shell is coated with an active material, and finally subjected to another heat treatment, - it is based on the principle that for the production of the solid core, 50-65 t% finely ground soapstone powder, 15-35 t% soapstone powder and/or talc powder fired at 1200 ⁺⁵ ° °C, as well as 4-7 t% magnesium carbonate and 5-91% barium carbonate, and optionally 0.1-0.2 t% rutile type titanium dioxide are used as the raw material, then the raw material is shaped by pressing and pre-fired at 75 0* ¹⁰ °C, then a porous shell is applied to the interface of the solid core thus prepared by dipping and/or spraying 6-14 t% fine-grained calcined alpha-corundum, 4-9 t% white-burning plastic fine clay, 55-68 t% raw fat-rock flour and 22-28 t% fat-rock flour also fired at 12OO ⁺⁵⁰ °C, as well as 3-12 t% paper industry shredded cellulose fiber, 0.1-0.2 t% ammonium lignosulphate and 0.2-0.8 t% trimethylcellulose with a molecular weight of 1000-5000, a material mixture with a bulk density of 1250-1300 g/1 is applied, the thickening of the porous shell layer is continued until the theoretical layer thickness of the porous shell after firing reaches a value of 0.6-1.1 mm, the formation of the porous shell After that, the boundary body is dried and fired at 12OO ^±10 °C, then the boundary body with a solid core and a porous shell is dipped once or more in a melt of Ni-Mg double salt with additives and the excess is removed from the boundary body, and thus the boundary body is provided with an active material coating, and finally the boundary body with the active material coating is subjected to heat treatment at 600 ^±10o C.

A further feature of the process according to the invention may be that a melt of nitrate hexahydrate at a temperature of 96°C is used as the Ni-Mg double salt.

In a favorable embodiment of the process, finely divided efficiency-improving and accelerating additives are mixed with the Ni-Mg double salt before dipping the boundary body having a solid core and a porous shell.

The most important advantage of the solution according to the invention is that, thanks to the novel design and composition of the boundary body, a relatively small amount of active material, i.e. instead of filling the pore volumes of the entire mass of the carrier body, is only a surface active material amount of a specific layer thickness, i.e. - the previous active material amount

A very high activity, very stable and efficient reaction can be achieved with a fraction of -6, while the confining body has high heat resistance and thermal shock resistance, thus greatly increasing the lifetime of the confining body.

It is an advantage that the device according to the invention, due to the specific surface porous layer, the active material coating and the given reductive target process, typically performs the circular decomposition of hydrocarbon middle distillates and the gases introduced into its environment, especially water vapor and carbon dioxide mantle. In particular, the optimal transformation of the CH ₄ , H2 and CO2 chain and the re-production of given elements can be realized, with the help of the extremely efficient catalytic and pyrolysis effect optimized from an environmental safety point of view.

Among the advantages is that due to the limiting body produced thanks to the specific manufacturing process, the amount of active material coating required to achieve the desired limit can be smaller, which also reduces the amount of expensive metal alloy components, and therefore the initial cost of the equipment can be much more favorable.

A further positive effect of this is that such equipment can be used in larger quantities for the destruction of hazardous materials and waste - due to the favorable price range - which means that the emission of environmentally harmful combustion products during destruction can be essentially completely eliminated.

The device according to the invention will be described in more detail below in connection with an exemplary embodiment, based on the drawing. In the drawing,

Figure 1 is a schematic view of a variant of the device with a limiting body according to the invention.

Figure 1 shows a schematic view of the device 1 according to the invention. It can be observed that the reaction space 2 for the destruction of gaseous combustion products generated during combustion is enclosed by the boundary body 20. The boundary body 20 can be composed of various geometric shapes. In our case, the boundary body 20 is formed by a cylindrical shell section 24 and a dome section 25, but a longer boundary body 20 consisting of several cylindrical shell sections 24 is also conceivable. The boundary body 20 can have a geometric shape different from the cylindrical shell section 24 and the dome section 25, e.g. a conical shell section.

-7 The barrier element 3 is also located in the reaction space 2, which is important for the control of pre-combustion and post-combustion. It should be noted here that the structure and operation of the device 1 are essentially the same as those described in detail in the patent specifications HU 206.148 and HU 225.373, so they will not be described separately here, as they belong to the state of the art.

The significant difference from the known solutions is in the design of the boundary body 20. The 20 >

The boundary body is structurally composed of the solid core 21, the shell 22 covering the interface 21a of the solid core 21 and the active material coating 23 on the outer surface 22a of the shell 22. The solid core 21 contains 75-85% by weight of finely ground and partially fired soapstone powder at 1.2OO ⁺⁵⁰ °C, 6-111% of plastic white-burning fine clay, and 4-7% by weight of magnesium carbonate and 5-9% by weight of barium carbonate as a flux, and 0.1-2.0% of rutile-type titanium dioxide. The interface 21a of the pressed solid core 21 is shaped as a wavy piece of marble according to a sinusoidal curve, in which - depending on the reactor types - the ratio of the average diameter to the height is between 0.3:1.0 and 1:1.

In the case of corrugated core diameters, the ratio of the outer/inner diameters is also within the appropriate values. These ratios are slightly modified by the porous surface shell 22, but this modification is not significant. The size of the outer core diameter itself - also depending on the reactor type - should be chosen between 10-1000 mm values.

The shell 22 located on the interface 21a of the solid core 21 has a porous structure, the expedient composition of which is 6-14 t% fine-grained calcined alpha-corundum, 4-9 t% white-burning plastic fine clay, 78-89 t% raw and burnt fat-stone flour, which contains 3-12 t% paper industry shredded cellulose fiber, 0.1-2.0 t% ammonium lignosulfonate, 0.2-0.8 t% trimethylcellulose (Ms: 1,000-5,000) as a milling additive. The thickness of the shell 22 in the finished state of the boundary body 20 is 0.5-1.1 mm.

The active material coating 23 located on the outer surface 22a of the porous shell 22 of the boundary body 20 consists of 0.64-0.76 mol% nickel nitrate hexahydrate and 0.23-0.28 mol% magnesium nitrate hexahydrate, which includes 0.48-0.65 t% TiO ₂ , 0.16-0.38 t% GaO ₂ , and 0.05-0.25 t% ZnO ₂ calculated on the original weight as efficiency-enhancing and accelerating additives.

-8The operation of the apparatus 1 according to Figure 1 is - as already mentioned - essentially identical to the operation of the apparatuses described in detail in the patent specifications HU 206.148 and HU 225.373, so this will not be repeated here. The difference is that thanks to the novel ceramic structure forming the limiting body 20 and the minimal active material coating 23 placed on the shell 22, the nitrogen and sulfur removal reactions take place completely, quickly and stably.

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The method according to the invention is illustrated below by way of example.

Example 1:

In this process variant of the structural design of the boundary body 20, to produce the solid core 21, 50-65 t% finely ground soapstone powder, 15-35 t% soapstone powder and/or talc powder fired at 1200 ^+50o C, as well as 4-7 t% magnesium carbonate and 5-9 t% barium carbonate, and optionally 0.1-0.2 t% rutile-type titanium dioxide were mixed, then the material mixture was ground by aqueous fine grinding using a known ceramic industrial method, sieved, de-ironed, and finally dehydrated. After that, the shape corresponding to the boundary body 20 was formed from the ground material by extrusion and dried, and then pre-fired at 75O± ¹⁰ °C. During the extrusion process, the die was designed so that during the molding, the boundary surface 21a of the solid core 21 was corrugated according to a sinusoidal curve, where the average diameter/height ratio was 0.5.

Independently of the preparation of the solid core 21, in our case, the coating mass forming the shell 22 was prepared during the firing of the solid core 21. In the process, a fine-ground slurry with a bulk density of 1250-1300 g/1 was prepared, consisting of 6-14 t% fine-grained calcined alpha-corundum, 4-9 t% white-burning plastic fine clay, 55-68 t% raw fat-oil meal and 22-28 t% fat-oil meal also fired at 12OO ⁺⁵⁰ °C, as well as 3-12 t% paper-industrial shredded cellulose fiber, 0.1-0.2 t% ammonium lignosulfate and 0.2-0.8 t% trimethylcellulose with a molecular weight between 1000-5000.

It should be noted here that in order to form the thin porous shell 22 that will be turned over later, very fine grinding had to be performed so that the permissible sieve residue on a DIN 10,000 sieve can be a maximum of 0.2%.

-9 After preparing the fine-ground slurry, the pre-fired solid core 21 was dipped in the slurry serving as the base material for the shell 22 so that the layer thickness of the shell 22 formed on the interface 21a of the solid core 21 was 0.65-1.1 mm. After forming the shell 22 of the desired thickness, the boundary body 20 was dried and then fired at 1,280± ^10o C.

In order to activate the fired boundary body 20, it was dipped into a bath once or more to achieve the desired surface saturation and peaking, and thus the active material coating 23 was created. For the bath suitable for forming the active material coating 23, 0.64-0.76 mol% nickel nitrate hexahydrate and 0.23-0.28 mol% magnesium nitrate hexahydrate melted at 96°C were used, in the melt of which 0.48-0.65 t% TiO ₂ , 0.16-0.38 t% GaO ₂ , and 0.05-0.25 t% ZnO ₂ were suspended, calculated on its original weight, in order to achieve the fine-grained structure, these were precipitated together and/or separately from organic compounds in a known manner. Finally, the dipping was repeated several times in order to completely saturate the outer surface 22a of the shell 22, and the excess impregnating material for forming the active material coating 23 was separated from the outer surface 22a of the shell 22 of the boundary body 20 by short-term, low-amplitude vibration. The boundary body 20 thus activated was repeatedly fired at 6OO± ¹⁰ °C, and thus we finally obtained the boundary body 20 with the desired shape, composition, and structural design.

The device 1 with the specific 20 boundary bodies according to the invention can be used well in any place where hazardous and/or waste materials need to be destroyed in an environmentally friendly manner.

Claims (9)

- 10 PATENT CLAIMS 1. Catalytic pyrolysis device primarily for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, which comprises a boundary body enclosing a reaction space and an active material coating at least partially covering the inner side of the boundary body, where the boundary body is a ceramic material with a solid core and a porous structure shell having cavities suitable for receiving particles of the active material coating on at least the boundary surface of the core facing the reaction space, and the active material coating has a nickel base containing magnesium, characterized in that the core (20) of the boundary body (21) is made of protoenstatite stabilized with a glass phase and sintered to a compact state, and the porous shell (22) at least partially covering the core (21) is made of magnesium silicate doped with alpha-corundum with a thickness of 0.6-1.1 mm, on the porous structure outer surface (22a) of the shell (22) The active material coating (23) located thereon contains Ni-Mg oxide produced by heat treatment from Ni-Mg double salt and optionally Ni-Si components. 2. The device according to claim 1, characterized in that the limiting body (20) has a cylindrical shell section (24) and a dome section (25), as well as an inlet and an outlet, and is further supplemented with a blocking element (3). 3. The device according to claim 1 or 2, characterized in that the longitudinal cross-sectional view of the interface (21a) of the solid core (21) in contact with the porous shell (22) is wavy in the form of a sinusoidal curve, where the ratio of the mean diameter and height of each wave is between 0.3-1. 4. The device according to any one of claims 1-3, characterized in that the outer mean diameter of the interface (21a) of the solid core (21) in contact with the porous shell (22) is between 10-1000 mm. 5. The device according to any one of claims 1-4, characterized in that the active material coating (23) formed from the NiMg double salt contains 0.64-0.76 mol% nickel, 0.23-0.28 mol% magnesium and optionally Ni-Si. 6. The device according to any one of claims 1-5, characterized in that the active material coating (23) contains, as an efficiency-enhancing and accelerating component, 0.48-0.65 t% titanium dioxide, 0.16-0.38 t% gallium dioxide, and 0.05-0.25 t% zinc dioxide, based on the weight of the active material calculated in the form of the nitrate hexahydrate salt. 7. Method for producing the structure of the boundary body of a catalytic pyrolysis device suitable primarily for neutralizing hazardous combustion products and waste materials, destroying flue gases and utilizing complex carbon chains, during which a core material is formed, the formed core is subjected to heat treatment, then coated with a shell former, then subjected to another heat treatment, then the shell is provided with a coating of active material, and finally subjected to another heat treatment, characterized in that for the production of the solid core (21) 50-65 t% finely ground soapstone powder, 15-35 t% soapstone powder burned at 1200 ⁺⁵ ° °C and/or talc powder, and 4-7 t% magnesium carbonate and 5-9 t% barium carbonate, and optionally 0.1-0.2 t% rutile type titanium dioxide are used as the raw material, then the raw material is shaped by pressing, and 750 It is pre-fired at ^±10o C, then a material mixture with a bulk density of 1250-1300 g/1 containing 6-14 t% fine-grained calcined alpha-corundum, 4-9 t% white-burning plastic fine clay, 55-68 t% raw fat-rock meal and 22-28 t% fat-rock meal also fired at 12OO ⁺⁵⁰ °C, as well as 3-12 t% paper industry shredded cellulose fiber, 0.1-0.2 t% ammonium lignosulfate and 0.2-0.8 t% trimethylcellulose with a molecular weight of 1000-5000 is applied to the interface (21a) of the solid core (21) thus prepared as a porous shell (22) by dipping and/or spraying, the the thickening of the porous shell (22) layer is continued until the theoretical layer thickness of the porous shell (22) after firing reaches a value between 0.6-1.1 mm, after the formation of the porous shell (22), the boundary body (20) is dried and fired at 12OO ^±10 °C, then the boundary body (20) with a solid core (21) and a porous shell (22) is dipped once or more in a melt of a Ni-Mg double salt with additives and the excess is removed from the boundary body (20), and thus the boundary body (20) is provided with an active material coating (23), and finally the boundary body (20) with the active material coating (23) is subjected to heat treatment at 6OO ^±10 °C. 8. The method according to claim 7, characterized in that a melt of nitrate hexahydrate at a temperature of 96°C is used as the Ni-Mg double salt. 9. The method according to claim 7 or 8, characterized in that finely distributed efficiency-improving and accelerating additives are mixed with the Ni-Mg double salt before dipping the boundary body (20) having a solid core (21) and a porous shell (22). The authorized person