DD288392A5 - METHOD FOR REMOVING SULFUR HYDROGEN FROM CARBON DIOXIDE-CONTAINING GASES - Google Patents

Abstract

The invention relates to the field of gas purification, in particular in the material converting and coal processing industry after * The process for removing hydrogen sulfide from carbon dioxide-containing gases reduces the required in the desorption of the loaded detergent by the expense, the running off of different sections of the absorber detergent The reason of the different load is regenerated separately. {Hydrogen sulfide; carbon dioxide; Sulfosolvanlauge * gas purification; Absorption; desorption}

Description

For a gas with a CO ₂ content of 70-95 parts by volume in%, predominantly 80-90 parts by volume in%, and one HjS content of 10-30g / m ³ i. N., predominantly 15-30 g / m ³ i. N., it was found that with 4 Perform contact trays (R) and one Liquid load of 0.5 to 1 m ³ Sulfosolvanlauge per 1000m ³ 1. N. gas (predominantly 0.6-0.8m ³ Sulfonsolvanlauge each

1000m ³ i. N. Gas) the Laugebeladung a hydrogen sulfide to carbon dioxide ratio greater than 1 achieved.

In the upper leaching task, which is required especially to achieve a high final purity, to be purified gas

and Sulfosolvanlauge passed in countercurrent to each other. To achieve a high final purity, it is necessary that

Liquid load 3 1m ³ Sulfosolvanlauge / 1000m * i. N. adjust. The Laugebeladung reached depending on the Gas concentration a hydrogen sulphide to carbon dioxide ratio of less than 0.7. The minimization of the amount of gas to be concentrated in the second absorption stage is achieved by extracting from the

individual column sections running laden Sulfosolvanlauge is regenerated separately.

The loaded Sulfosolvanlauge the upper column section is thermally regenerated in a known manner, and the

resulting desorption gas is supplied for further concentration of the second absorption stage.

In contrast, during thermal regeneration, the loaded sulfosolvanic acid of the lower one is formed Column section, a desorption gas whose hydrogen sulfide concentration direct feed into a

unmodified Clausprozeß allows.

embodiment The invention will be described below by means of an embodiment of the field of gas purification in the Kohledgassung be explained in more detail. The raw gas A to be desulphurised is fed to an absorber 1, where it is regenerated in two stages with regenerated sulphosol solution B

is contacted in countercurrent and then leaves the process as clean gas C. The loaded Sulfosolvanlauge D from the upper

Section of the absorber 1 passes through the container 2 and the pump 3 and the heat exchanger 4 in the desorber 5. In

this is released by heat, the absorbed gas components and the loaded Sulfosolvanlauge D

regenerated.

The regenerated Sulfosolvanlauge B is via the pump 6 and the heat exchanger 4 in the upper portion of the Absorber 1 returned. The released in the desorber 5 gas E passes to the absorber 7. After contact with the regenerated Sulfosolvanlauge H leaves the gas I the absorber 7 and the raw gas A is added. The loaded Sulfosolvanlauge F of the lower portion of the absorber 1 passes simultaneously with the from the absorber. 7

exiting loaded Sulfosolvanlauge F via the container 8, the pump 9 and the heat exchanger 10 in the desorber 11th

The resulting in the desorption gas G is fed to an unmodified Claus process. The regenerated Sulfosolvanlauge H exiting from the desorber 11 is 10zu via the pump 12 and the heat exchanger

promoted the absorbers 7 and 1 (lower section).

Claims (1)

-1- 288 302 Claim: Process for the removal of hydrogen sulphide from carbon dioxide-containing gases by means of sulphosol (R), in which, due to the high carbon dioxide content of the gas to be purified, a two-stage concentration of the desorption gas is required and the absorber (s) have at least two sulphonate sulphate feed and abatement, characterized by that the sulfosolate discharged from the absorber (s) is discharged separately and regenerated in such a manner as to regenerate the portion of the charged sulfoside rich in hydrogen sulfide, and to supply the resulting desorption gas to the downstream Claus plant, during the Part of the Sulfosolvanlauge regenerated with the low hydrogen sulfide loading in a known manner and the resulting desorption gas is fed to a further absorption stage for concentration. For this 1 page drawing Field of application of the invention The invention relates to the field of gas purification, in particular the removal of hydrogen sulfide from carbon dioxide-containing gases of the substance-converting, in particular the coal processing industry according to the Sulfosolvan process (R). Characteristic of the known state of the art It is known that gases which contain carbon dioxide in addition to hydrogen sulfide, by means of absorption liquids containing as an effective component alkaline compounds such as aqueous solutions of soda or potash, salts of strong inorganic or organic bases with weak organic acids, amines, etc., Hydrogen sulfide and carbon dioxide can be washed out. The weak gaseous acids are dissolved by the absorption liquids in the cold and released again in the heat. (J. Schmidt; "Processes of gas treatment", VEB German publishing house for basic industry, Leipzig, 1970,192-212) For the selective removal of hydrogen sulfide the potassium salt of dimethylaminoacetic acid (Sulfosolvanlauge (Rl) is particularly suitable. It is also known (DR-PS 654373) that the absorption rate of hydrogen sulfide is greater than that of carbon dioxide. Therefore, a short contact time between gas and brine is required to achieve high hydrogen sulfide loading in the sulfosol. In order to achieve a high end purity of the gas to be desulfurized, the absorber to achieve a high driving force for mass transfer with several Laug taufgaben performed (DD-PS 262170). At a high carbon dioxide content in the gas to be cleaned (70 volume percentages) is a concentration on the resulting desorption during the thermal desorption gas required. The resulting gas during desorption is treated once again with sulfosol. The resulting gas during desorption has a hydrogen sulfide content of> 45 volume percentages and can be oxidized in an unmodified Claus plant to elemental sulfur. The disadvantages of the two-stage method consist in a high energy and increased equipment costs. In addition, the liquor consumption increases on the one hand by increased losses and on the other hand from the faster aging. Object of the invention The aim of the invention is to concentrate from a carbon dioxide-containing gas hydrogen sulfide with minimized energy, plant, and excipient expenses such that it can be processed directly in an unmodified Claus process. Explanation of the essence of the invention The invention has for its object to minimize the amount of gas that must be supplied to concentrate the second absorption stage. According to the invention the object is achieved in that the absorber or the absorber of the first liquor cycle, the Sulfosolvanlauge is placed separately into individual sections of the absorbent. The Sulfosolvanlauge is distributed to at least two leaching tasks, with a leaching task in the upper and a second in the middle part of the absorber is arranged. The supplied in the middle part of the absorber Sulfosolvanlauge passes through mass transfer elements with the bottom of the absorber entering gas in contact. Surprisingly, it has been found that the amount of gas and composition taken up by the sulfosol hydroxide solution is dependent not only on the residence time but also on the amount of sulfosol sulfate fed in.