DE1444974A1 - Method and device for gas desulphurization - Google Patents

Description

Dr.-lng. G. Eichenberg Dipl.-ing. H. Sauerland

Patent attorneys « _Λ - ·» «*»

Düsseldorf 10, 2.0 · ....! · .. 1959

Bank account: Cecilienallee 76

Deutsche Bank AG., Düsseldorf branch λ Λ Λ AQ 7 A

Postal check account: Essen 8734 I * t H * + O / t

Telephone number 432732

Method and device «ur gas ontsehwsfslun« ·.

It is known that industrial gas ·, sB · iokeofengaa la dar Iel · · can be desulfurized by passing them through an absorption vessel made of one or more of the oxides, usually bison or oxide beddingβ contains fluidized beds. Oxide is regenerated by burning under oxidizing conditions in a "special generating vessel, with lines being open to allow a continuous" wipe of the absorption "and the generating vessel to circulate. In the practical implementation of this method using tob Bisen- or manganese oxide is the oxide at an operating temperature in AbsorptionsgefJtss tob 320 held to 400 ⁰ C and the oxide erhitst by combustion of the sulfur in the regeneration vessel to a high temperature, which in practice "as Soheb 600 UBd 900 ⁰ C lies.

Laughing the feet positions of the applicant of Method E * of the HJS from a lohgas with approximately 1 Volurn ^ H can to 95 when carrying in the Torbeechriebenen white 90 ₂ S removed in a Abeorptionegefäss with "wj & Eiaenoxydechichten ron of 0.3 to 0 _V 6 m depth will.

For many industrial purposes, in order to operate τοη steel furnaces, this degree of enteohulphurization is sufficient because the remaining 5 Ms XOfi dssureprüngliohen H ₂ S, ie 0.05 to 0.1 Tolurn ^ R ₂ S * are not β · οβ enough to Creating difficulties in performing the procedure for which the Sas is used. In contrast door is one colander τοη other Verwendunge- "weeken a much more extensive desulfurization much j particular needs the town gas to below a so low?" IjS-Oehalt be desulphurized that practically one τοίΐ-constant Intsehulfelung is gate. It may be necessary to reduce the IgS content to as little as one part per million.

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For the letter of 20 »1» 1959 ^αη the German Patent Office ^sheet / r ,

The applicant has now found that the continuous and repeated heating to high temperatures considerably reduces _{the absorption capacity of the oxide for H 2 S} Coke oven gas at 36O ⁰ C and sulfur removed when using a single layer as the ordinate and the sulfur content of the layer in? T as the abscissa, although for an iron oxide under three different conditions, curve A refers to the oxide once roasted to 45O ⁰ C, curve B on the roasted again at 65O ⁰ C iron oxide and curve C on the oxide after repeated Schwefelentfernungs- and Regenerierungeumläufen. This shows that the fresh, ie. Oxide roasted once at a comparatively low temperature has an initially high sulfur-removing capacity and its initial sulfur-removing capacity is lower once it has been roasted at a higher temperature and its sulfur-removing capacity is greatly reduced when it has been regenerated repeatedly.

In this way, the regeneration of the oxide results in a reduction in its ability to remove sulfur compounds when it is returned to the absorption vessel to maintain a state of maximum effectiveness.

The applicant then found that an oxide v © n reduced effectiveness, if at all, practically complete Desulfurization can only result if six to eight fluidized beds are used in the absorption vessel « While this procedure is not impossible in itself, it is But difficult to carry out and the circulation of the oxide between these numerous layers and the regeneration vessel Conditionally Intricate Mechanical Precautions and a Increase in operating costs,

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In accordance with the load, the gases will therefore pass through after they have passed through the absorption vessel, with any remaining sulfur bonds contained, by one or more, from heieseii "Oxide" is directed from existing fluidized beds, that is, from one Oxide that has not been introduced into circulation and then there may or may not be introduced into this circulation. The layer or layers of fresh oxide is or are kept in the flow path of the gases above the return line from the regeneration vessel and can by the gas itself in liquid-like State, i.e. by containing the remaining sulfur compounds to be removed Gas·

The layer (or layers) consisting of fresh oxide can be in the upper part of the absorption vessel or in a separate one Container, d * h · in an auxiliary absorption vessel or in both to be provided

As long as the fresh oxide does not enter the circuit, it remains in a state of maximum effectiveness and thus almost completely removes the remaining part of the sulfur compounds from the gas leaving the oxide circulation system. In fact, the length of time during which the fresh oxide can be in contact with the gas, but outside the circulation system, is only limited by the amount of sulfur that it is allowed to absorb fresh oxide layer must be kept low. In view of the fact that most of the sulfur in the original gas is removed from the main absorption vessel, the total amount absorbed by the fresh oxide outside the circulation system is small, so the fresh oxide can remain outside for 100 hours or more "Me this system applicant has also found" that, to achieve the maximum Bntschweflungsgrades (down to 1 hawks per million or less), advantageously, the temperature of the final layer below 200 ° 0, and should preferably be maintained at approximately 100 ⁰ C * this may in the way that the final layer is placed in a separate vessel d a heat exchanger or j

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a radiator is connected in the path of strömeniden between the two vessels gases · ₍

In the circulation system there is always dust, τοη which a XeIl is carried away by the gases. It is advantageous to allow the fresh oxide to enter the circulation system after the sulfur removed, which is carried away from this system and to add fresh oxide to the plant in a mass that is necessary is to replenish the oxide removed as dust * This feed rate corresponds to a complete replacement of the oxide in the plant about once a week »

The fresh oxide is released through the passage of the hot, the oxide Gases leaving circulation system kept hot; as a result of the low rate of feed of the oxide, the heat absorbed is " amount small »

Figure 2 shows schematically an embodiment of the system according to the invention with a separate aid absorption vessel » As can be seen from this figure, there is a main absorption vessel 1 is provided with two gas-permeable supports 2 and 5, on which the oxide layers 4 and 5 rest, which are kept in a liquid-like state by the gas to be cleaned and entering through a line 6. The oxide flows from the Layer 4 to layer 5 via a line 7 and then exits from layer 5 via a line equipped with a Hegel valve 15 Line 8 from the container 1, whereupon it arrives in the line 9, in which it is pneumatically to a generator 10 is conveyed X in this vessel the liquid-like ** The chemically held oxide hit the aid of air that armed enters the Gtfase 10 through a line 11; after took place « Büsten then flows back the oxide via a line 12 to the layer 4 in the tank 1 »

»The parts described above form the oxide circulation system. Including in a suitable temperature in the absorption chamber without this system Use of a source of heat is maintained

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the oxide rom vessel 1 to vessel IO and back again preferably put into circulation so quickly that one of the oxide masses in the Regeneration and main absorption vessel have the same mass in less than 4 hours and usually once an hour through the system "The air leaves the Eegonoriergefäß 10 over • in a line 13 »also the aio enters a cyclone dust collector",

In the absorption vessel 1 there is a third gas-permeable carrier 16 with a fluidized bed 17 made of fresh oxide, which passes from this layer via a line 19 to the layer 4. The gas leaving the vessel 1 flows via a line 18 and a heat exchanger 20 into an auxiliary absorption vessel 2I ₉ in which on a gas-permeable base 23 a layer of fresh oxide rests on a lirbslao layer * From this layer the oxide can reach layer 1? Via a line 24.

Layers 5 # 4 and 17 are all kept at temperatures not below 320 ° C. The water to be cleaned flows through these layers at a speed that is sufficient on the one hand to keep the layers in turbulent motion and on the other but is not sufficiently high to more blow than a keel "nen part from the Schioht directly" that the plant above the line 19 leaving Sas is cooled to about 100 ⁰ C in the heat exchanger 20 by heat exchange with the flowing to the conduit 6, the. As a result, the temperature in the 3chioht 22 is approximately 100 ⁰ C, whereby the volume of the gas is reduced and its viscosity is increased. accordingly the durometer of layer 22 is approximately 25 pounds smaller than the diameter of the lower layers »

Bas flowing out of the auxiliary absorption vessel 21 Gas passes via "· in line 25 in a Zyklonstaabsammler 26. The fresh · oxide is the Kilfsabsorptionsgefäss 21 by means of a screw conveyor 27 from a container 28 fed ₀

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The total feed is regulated in such a way that it corresponds to the amount of dust accumulating in the collectors 14 and 26 included. E2S picked up from layers 5 and 4, approximately 2.7 # from layer 17, and practically all of the remainder from layer 22, with less than a portion of a million remaining in the draining Sas. Also, nearly 90 $ of organic S compounds _w ere this away.

In the above system, the layers 4 and 5 for Oxydumlaufsy s tem include, while 22 and 17, the layers consist of fresh oxide which is slowly fed by means of the screw conveyor * "Since, however, other layer combinations are possible, the invention is not limited to the use of 4 layers or to the special arrangement of 4 layers as has been described. So 3 layers of regenerated ^ oxyd can be used, which can be followed by a © or possibly two layers consisting of fresh oxide * In all cases the main desulphurisation is carried out in the © of the continuously circulating layers in d @ a The desulphurisation in the surface layer or layers made up of fresh oxides only needs to be kept at a lower temperature if the treated material is required to be clean and pure if this is not the case dispenses with the heat exchanger 20 and warden the SchluSsefeiaht 22 are arranged either in a auxiliary Absorptionegefäss (such as 21) ren same diameter as the Hauptabsorptionsgefäs® 1, as well as it is possible to un all layers in sinsss single Abserpfirnisgefäss * »terzubringen * From the Amsel & erin was found weräea "that in such a system with 4 Qxjä & Qh ± oht®n _t which were operated at a f®isperatur of about 320 ⁰ C. , 99 _? S # äes H2g were removed from a similar Eolcsofengaa uni the abetriaiende 0as 20 files EGS per milli © n contained »

You invention can übereil lines application there, vo a Oxji for removal of S-compounds used wix ^ l ₉ the aur Hückbildung Bittele oxidizing 3aee is regenerated "Yes special" smokes

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since "the oxide used is not necessarily *!" • iron or hangan oxide BU B "in _t even though one of these oxides is normally used Oxide, because it is either used pure or applied to a carrier made of kaolin or another aluminosilicate * Naturally decaying sours are not equally reactive. Magnetite 2.1 «are less reactive than Haaatite. In practice it is therefore desirable to use any known deposits with high reactivity. Nevertheless, it can be said that all these oxides lose the least amount of leakage as a result of repeated heating to high temperatures and consequently the invention. may find advantageous application as ever may be daa Terwendete oxide · latürliohe Ilsen- or manganese oxides normally contain some free water and some also bound water "gateway make their Terwendung the invention retracts, must therefore at temperatures below 200 ⁰ C to dry, to remove all of the free water, but they can also be roasted in order to remove all or part of the bound water over 650 ⁰ O for 1 1/2 hours The effectiveness of the ore is little affected because - as Figure 1 shows - the regenerative, repeated roasting and not an individual roasting affects the effectiveness of the ore. that it comprises once roasted oxide, provided that the oxide is not introduced into the Bolaufsystem

j claims.

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Claims (1)

1 «) Process for the desulphurisation of industrial gases containing S compounds. Using one or more of the Sas to be cleaned, arranged in an absorption vessel. Neten hot fluidized beds, which consist of oxide, which j continuously between the absorption vessel and a sofa to regenerate the oxide by Erliitaen circulates under oxidizing conditions, characterized in that the after Passage through the absorption vessel still remaining Gases containing S-compounds after leaving the absorption vessel through one or more fluidized beds of helssem fresh oxide " 2 «) Method according to claim 1 _f characterized» that the hot, fresh oxide is kept in a liquid-like state by the hot gases containing the remaining S-compounds that have yet to be removed. 3 ·) Method according to claim 1 or 2, characterized in that. the fresh oxide, after the remaining S-bonds have been removed, is introduced into the circuit and continuously in one Amount is supplied which corresponds to the amount of oxide separated as dust from the cycle « 4 «) Process according to one of claims 1 to 3» characterized in that «the temperature of the hot, fresh oxide through which the gases flow is kept below 200 ⁰ O» 5 ") Plant for carrying out the method according to claim 2 with" in "absorption vessel _t a regeneration vessel, devices sublia ~ directing the su-purifying oase into the absorption vessel for transferring the oxide contained therein into a liquid" -like state and connections to the Enabling of a circulation of the oxide between the absorption and regeneration vessel, characterized by the fact that devices are provided by means of which the layer (or layers) of fresh oxide in the stream ^ the oasis can be switched to the layer («4er Sent) made of fresh oxide by the ror of its discharge INSPECTED 909805 / 0B09 as valid ·· 9m Ια tintn liquid-like state see below 6) Anlage naoh Anepraoh 5 _{9 can be} identified by an in the flow swell gd «r imsawieohen di · 3ohlui3aoaioiit and the Sohioht included heat exchanger or cooler « 909805 / 08Of