WO2012059185A1 - Process for removing c2 to c5 aldehydes and other oxygen-containing organic components of chain length from c2 to c7 from a gas stream in a polyethylene plant - Google Patents

Abstract

A process for removing C₂ to C₅ aldehydes and other oxygen-containing organic components of chain length from C₂ to C₇ from a gas stream (1) in a polyethylene plant, wherein the gas stream is contacted with water (2) in at least one apparatus (5) for performance of an absorption, and the aldehydes and/or the other oxygen-containing organic components are absorbed by water to form a gas stream (4) depleted of aldehydes and/or other oxygen-containing organic components and a water stream (3) enriched with aldehydes and/or other oxygen-containing organic components, both of which are removed from the at least one apparatus for performance of the absorption, and the water stream enriched with aldehydes and/or other oxygen-containing organic components is contacted with a stripping gas (8) in at least one apparatus (6) for performance of a desorption, which strips out the aldehydes and/or the other oxygen-containing organic components to form a water stream (11) depleted of aldehydes and/or other oxygen-containing organic components and a stripping gas enriched in aldehydes and/or other oxygen-containing organic components, both of which are removed from the at least one apparatus for performance of the desorption, using, as a stripping gas in the at least one apparatus for performance of the desorption, various fuel gases of a wide variety of different compounds of the elements C or H or mixtures thereof, preferably natural gas, and passing the stripping gas enriched with aldehydes and/or other oxygen-containing organic components directly to a flare in which it is incinerated.

Description

Process for the removal of C ₂ to C ₅ aldehydes and other oxygenated organic components having a chain length of C ₂ to C ₇ from a gas stream in a polyethylene plant The invention relates to a process and apparatus for the removal of C ₂ to C _{2 5} aldehydes and other oxygenated organic components of a

Chain length of C ₂ to C ₇ from a gas stream in a polyethylene plant. The invention is distinguished, above all, by an extremely low-cost removal of these aldehydes.

For example, in the LDPE process, it is necessary to remove propanal from the forming ethylene-purge gas stream. Propanal is currently the most commonly used modifier and has largely displaced the commonly used propylene.

In the usual purification of the purge gas is proceeded in three stages. With a basic wash, first the C0 _{2 is} removed. In order to limit the consumption of NaOH here, the detergent is circulated and discharged only a small part. When propanal is in the purge gas, the propanal in that cycle accumulates until it is no longer absorbed and remains in the purge gas.

In the second step, the vaporized in the basic wash water is removed with a molecular sieve. In this case, a partial co-adsorption of the propane must be expected. The desorption, which is carried out with hot ethylene at over 200 ° C, it may cause problems because the (wanted in the reactor) instability of the propane at high temperatures can cause polymerization.

In the third step, the dehydrated ethylene is purified in a cryogenic distillation, wherein the ethylene is obtained together with ethane as impurity as medium boilers in a side draw. Methane is removed overhead as low boilers, in the swamp fall to the high boilers such as propylene, propane, butane, etc. on. Since the stream contains valuable substances, it is often fed to a catalytic hydrogenation. The propanal would also end up in this stream, but it is considered a potent catalyst poison and should not be present in this stream.

For this reason, we are looking for low-cost alternative solutions. Thus, some writings take advantage of the use of water as an absorbent. Water is Known as one of the worst absorbents ever. For this reason, those skilled in the art would rather avoid the use of water as an absorbent in a large industrial process and would prefer other absorbents. For example, glycols would make the absorption particularly easy, but a separate infrastructure would be required only for this purpose, which makes the whole thing very expensive. There is a need for alternatives and different ones

Methods of using water as an absorbent have been established in the past.

DE 2623463 A1 describes a method for removing formaldehyde from gas streams. In this case, the gas stream is brought into contact with water in countercurrent in an absorber and the formaldehyde-depleted gas and the formaldehyde-enriched water is removed separately from the absorber. The enriched water is then purified and recycled to part of the absorption stage. This purification is very complicated solved by distillation and aims to enrich the formaldehyde high. In addition, the detergent water is not intended to be completely rid of formaldehyde.

Water is also used as absorbent in WO 2007/071921 A1. In this case, a gas stream reduced to oxygen-containing organic compounds and a water stream enriched in such compounds are discharged separately from the absorption column. The laden water stream is withdrawn from the absorption stage and a portion of this stream is brought into contact with a stripping gas for desorption, whereby the absorbed gas components are stripped off and on to them

Components of depleted water flow is created. The purified water can

then be returned to the washing process. The loaded stripping gas is burned. However, as stripping gas, the gases are air, nitrogen and steam

proposed, which in turn must first be mixed with a fuel in order to eliminate them in a subsequent combustion, which is costly and

is expensive. In the process, it is additionally provided that the gas stream enriched with oxygen-containing organic compounds is washed with a bisulfite solution, which also makes the process economically complicated.

For this reason, it is an object of the present invention to provide an alternative method and apparatus for removing aldehydes of this type and other oxygen-containing organic components of a chain length of C ₂ to C ₇ from a gas stream, the process being extremely low in cost should. The object is achieved by a process for the removal of C ₂ - to C ₅ - aldehydes and other oxygen-containing organic components of a chain length of C ₂ to C ₇ from a gas stream in a polyethylene plant, wherein the gas stream in

at least one apparatus for carrying out an absorption is brought into contact with water and the aldehydes and / or the other oxygen-containing

are absorbed to organic components of water, wherein a depleted in aldehydes and / or other oxygen-containing organic components gas stream and an aldehydes and / or other oxygen-containing organic components enriched water stream, both of which are removed from the at least one apparatus for performing the absorption, and wherein the water stream charged with aldehydes and / or other oxygen-containing organic components is contacted with a stripping gas in at least one apparatus for performing a desorption, the aldehydes and / or the others

oxygen-containing organic components are washed out and an aldehydes and / or other oxygen-containing organic components discharged water flow and an enriched in aldehydes and / or other oxygen-containing organic components stripping gas, both of which are removed from the at least one apparatus for performing the desorption, wherein Stripping gas in the at least one apparatus for performing the desorption different fuel gases of various compounds of elements C or H or mixtures thereof, preferably natural gas, are used and the enriched with aldehydes and / or other oxygen-containing organic components stripping gas is passed directly to a torch, in which it is burned.

The use of water for absorption in a polyethylene plant is characterized by the fact that water is easily obtainable and infrastructures for qualitative

high-quality water at any chemical site anyway and do not need to be installed first. The poor absorption properties of the water can be compensated for by the high pressure that a purge gas stream to be purified

Polyethylene plant automatically brings when this between two

Compression levels is taken. The absorption is practically complete when relatively large amounts of water are used and also large areas are provided for the mass transfer, which leads to the use of very slender, high apparatus for absorption, which is preferably carried out in columns. The complete removal of the aldehydes and / or the other oxygen-containing organic components from the water is extremely important for the reuse of the water in the at least one apparatus for carrying out the

Absorption to have a large driving partial pressure difference in the absorber. This is the case with a poor absorbent such as water

accomplish that a pressure relief and relatively small amounts of a stripping gas in combination with a large mass transfer surface come to fruition. The

Pressure relief is achieved in that the at least one apparatus for carrying out the desorption is in direct communication with a torch, which is anyway present in a polyethylene plant and above controlled the pressure in the at least one apparatus for performing the desorption in a simple manner becomes.

As stripping gas various fuel gases of various compounds of elements C or H or mixtures thereof, preferably natural gas, are used in the at least one apparatus for performing the desorption desorption. It is important that the stripping gas does not cause any additional operating costs. At polyethylene sites, a central flare is usually operated, which is operated with natural gas as a pilot gas. The quality of the natural gas is not essential, as long as no larger quantities of elements except C and H are registered. An enrichment of the gas with C ₂ - to C ₅ -aldehydes and / or with other oxygen-containing organic components and with water is unproblematic. Also mixtures of different

Natural gas types up to highly hydrogen-containing gases are conceivable. Since the natural gas usually has a sufficient pressure, it can be used as a stripping gas and passed through the at least one apparatus for carrying out the desorption, before it burns as a pilot gas in the torch. The pressure of the apparatus for the

Carrying out the desorption is thus determined by the pressure in the torch line.

Except the C ₂ to C ₅ aldehydes and the other oxygen-containing organic components of a chain length of C ₂ to C ₇ are in a polyethylene plant

For example, still methane, ethane, propylene, propane, C0 ₂ and n-butane, which do not or only in very small amounts from the

Gas stream to be removed. Among other oxygen-containing organic components having a chain length of C ₂ to C ₇ in this context are preferably meant butyl acrylate and similar components. It can be a mixture of different

Aldehydes or an aldehyde of a single chain length, which is to be removed or other oxygen-containing organic components having a chain length of C ₂ to C ₇ or any mixtures thereof.

The discharged from the at least one apparatus for performing the absorption of aldehydes and / or other oxygen-containing organic components discharged gas stream is then usually in a

Polyethylene plant provided washing and purification steps supplied.

In an advantageous embodiment of the invention, the absorption in the at least one apparatus for performing the absorption in a temperature range of 20 ° C to 50 ° C, and preferably in a temperature range of 35 ° C to 40 ° C, performed. Advantageously, the process is carried out in a pressure range of 10 to 50 bar, and preferably in a pressure range of 20 to 40 bar. The aldehyde to be removed is preferably propanal.

Preferably, the other oxygen-containing organic

Component to butyl acrylate. As another example of the other oxygen-containing organic component are comonomers, such as vinyl acetate.

In a preferred embodiment, a partial stream of depleted of aldehydes and / or other oxygen-containing organic components water stream is passed into the at least one apparatus for performing the absorption in which it is used again for absorption, and another partial stream of aldehydes and / or depleted in other oxygen-containing organic components water stream is removed from the process. The rejection of some of the depleted in aldehydes and / or other oxygenated organic components water is necessary to avoid concentration of residual, non-desorbable remaining in the water aldehydes and / or other oxygen-containing organic components, otherwise the absorption properties in the at least an apparatus for performing the absorption would be impaired.

Optionally, fresh water is introduced into the at least one apparatus for carrying out the desorption, which has a temperature of 0 ° C to 120 ° C, and preferably from 80 ° C to 100 ° C. Preference is given to from the

Polyethylene produced condensate used. This causes a

Temperature increase in the at least one apparatus for carrying out the Desorption, which optimizes the desorption. Ie. the energy input at the head of the at least one apparatus for performing the desorption improves the desorption, whereby water is recovered in high quality, which in turn to the

Absorption can be used. To start the process, cold water should be used to ensure optimal functioning in the absorption device.

In a preferred embodiment of the method according to the invention, the volume flow of the stripping gas is kept constant at the inlet to the at least one apparatus for carrying out the desorption via a control device. As a result, the type of stripping gas, as described above, can vary as desired without

Recruitment of the process will be necessary. The purpose of the stripping gas is to reduce the partial pressure of the C ₂ to C ₅ aldehydes and / or the other oxygen-containing organic components in the gas phase. Therefore, the volume flow of the gas when entering the at least one apparatus for performing the desorption is crucial. This must be set to a fixed value. The normally measured mass flow of the gas is insignificant. Even fluctuating pressures in the torch lead are automatically compensated in this way. Higher pressures cause smaller volume flows, the control valve opens, and the higher stripping gas flow compensates for the desorption worsened by the increased pressure. This is the

Stripping gas volume flow related to the removal of the aldehydes and / or the other oxygen-containing organic components from the water the most sensitive

Controlled variable for the process according to the invention.

The fact that all facilities that are advantageously exploited here, are present in a polyethylene plant anyway, there are no additional

Operating cost. Also, the optional use of hot condensate only marginal operating costs, because water is removed from the steam system of the site. In addition, operating costs are only due to the necessary energy of the pumps.

The corresponding device for carrying out the method for the removal of C ₂ - to C ₅ -aldehydes and / or other oxygen-containing organic components from a gas stream in a polyethylene plant according to claim 1 comprises at least one apparatus for performing an absorption at the head end a supply line for water and at the lower end a discharge for aldehydes and / or others oxygen-containing organic components enriched water and at the lower end a supply line for aldehydes and / or other oxygen-containing organic components enriched gas and at the head end a derivative of aldehydes and / or other oxygen-containing organic components

has depleted gas and a transfer is provided by the aldehydes and / or other oxygenated organic components enriched water from the at least one apparatus for performing the absorption in fluid-conducting connection with at least one apparatus for performing a desorption, wherein the at least one apparatus for carrying out the desorption comprises a feed line for the water added to aldehydes and / or other oxygen-containing organic components at the top end and at the lower end a discharge for water depleted in aldehydes and / or other oxygen-containing organic components , And wherein at the lower end a supply line for fuel gas is provided, which rises in the at least one apparatus for performing the desorption upwards and at the head end a derivative is provided, the Mün in a torch det.

In a further embodiment of the device according to the invention, the derivative of the leads to aldehydes and / or other oxygen-containing organic

Components of depleted water from the at least one apparatus for performing the desorption as a partial stream in the head of the apparatus for performing the absorption.

Advantageously, a separate water supply to the at least one apparatus for performing the desorption is provided.

Preferably, the at least one apparatus for carrying out the absorption as an absorption column or bubble column, the at least one apparatus for carrying out the desorption as a desorption column or as a spray tower. The skilled person will use the most appropriate apparatus for removing the desired component. This selection is made by the expert on the basis of common knowledge. Any number of these devices can be combined with each other. This may be necessary especially when mixtures of different aldehydes or mixtures of aldehydes and other oxygen-containing organic components are to be removed from a gas stream of a polyethylene plant. For example, a large stream of water, as it is preferably necessary for the removal of butyl acrylate (see embodiment in Table 3), to a Deterioration of the desorption of propanal and thus to a worse result, while this large water stream allows the absorption of butyl acrylate first. In such a case, one would either increase the natural gas supply for desorption or, advantageously, sequentially absorb and desorb the individual substances in separate cascaded devices. That is, it would be one for each substance to be removed

Absorption device and a desorption necessary.

In a preferred embodiment, the at least one apparatus for performing the desorption with a control device, for controlling the volume flow of the fuel gas, provided.

The invention will be described in more detail with reference to Figures 1 and 2. 1 shows a simplified system diagram of a process for the removal according to the invention of C ₂ to C ₅ aldehydes and / or of other oxygenated organic components from a gas stream of a polyethylene plant. In the plant shown in Fig. 1, the absorption column _{5 is} fed to a gas stream 1 of a polyethylene plant, which is charged with C ₂ - to C ₅ -aldehydes and / or other oxygen-containing organic components of a chain length of C ₂ to C ₇ , In normal operation, this stream has a temperature of 45 ° C. and a pressure of 19 bar and enters the absorption column 5 at a mass flow rate of 500 kg / h. Except the C ₂ to C ₅ aldehydes and / or the other oxygen-containing organic

Components in the gas stream 1, for example, still contain methane, ethane, propylene, propane, C0 ₂ and n-butane, which are not removed via the pre-cleaning according to the invention or only in very small amounts from the gas stream. At the head of the

Absorption column 5, water 2 is introduced. This water 2 has a pressure of 20 bar, a temperature of 33 ° C and a mass flow of 3006.6 kg / h and is flowed through by the gas stream 1. In this case, the water 2 absorbs the aldehydes contained in the gas stream 1 and / or the other oxygen-containing organic components and can be used as aldehydes and / or other oxygen-containing organic components

discharged gas stream 4 with a mass flow of 493.4 kg / h at 33 ° C and a pressure of 19 bar are discharged from the process. Advantageously, the gas stream discharged to aldehydes and / or other oxygen-containing organic components is subjected to further purification stages such as basic scrubbing, molecular sieve treatment and / or subjected to a cryogenic distillation. That at aldehydes and / or at others

Oxygenated organic components enriched water 3, which results from the absorption is discharged from the process at a temperature of 34 ° C, a pressure of 19 bar and a mass flow of 3006.6 kg / h. The absorption is practically complete when relatively large amounts of water are used and large areas are provided for mass transfer, resulting in the use of very slender, high columns.

The aldehydes and / or with other oxygen-containing organic

Components enriched water 3, occurs after it has been relaxed at the top of the desorption column 6 in this. In countercurrent enriched with aldehydes and / or other oxygen-containing organic components water 3 is traversed with natural gas 8. The natural gas 8 has the task of reducing the partial pressure of the aldehydes dissolved in the water and / or the other oxygen-containing organic components. Therefore, the volume flow of natural gas 8 when entering the desorption column 6 is crucial and not the otherwise measured mass flow. This volume flow must be set to a fixed value. The pressure in the desorption column is reduced by the torch line, which has between 1 and 3 barabs. operated, determined. The

Desorption column 6 is in direct communication with the torch lead 7. Fluctuating pressures in the torch lead are also automatically compensated by the determination of the volume flow rate of the natural gas 8 when entering the desorption column 6. Higher pressures cause smaller flow rates, the control valve opens, and the higher

Natural gas stream 8 compensates for the deterioration due to the increased pressure absorption again. The natural gas 8 thus absorbs the aldehyde dissolved in the water and / or the others

oxygen-containing organic components, enters the torch line 7 and is burned there. The depleted in aldehydes and / or other oxygenated organic components water 11 is then removed from the desorption column 6 and partially as stream 12 of the absorption column with a temperature of 33 ° C and a pressure of 20 bar, at a mass flow of 3000 kg / h fed again. Another substream 9 of the depleted in aldehydes and / or other oxygen-containing organic components water 11 is discharged from the process to avoid accumulation of residual aldehydes in the circulation. Advantageously, the

Desorption column 6, a stream of fresh water 10 is supplied, which has a temperature of about 80 ° C and, for example, comes from a capacitor. This supports desorption in the desorption column. If necessary, several such apparatus sequences, as shown in Fig. 1 can be connected in series. This has the advantage that the respective amount of water for absorption can be adapted to the corresponding properties of the component to be removed. Thus, by variations of the apparatus sequence, the result of the

 Purification be positively influenced.

The invention will be explained in more detail with reference to three embodiments. The examples were based on the plant, as shown in Fig. 1, performed. The cited reference numerals in the tables also correspond to the reference numerals of FIG. 1.

In Table 1, a normal operation of such a system is shown, wherein the mass flows and their respective loading with a C ₂ - to C ₅ -aldehyde, has been used for the example Propanal.

Table 1: Normal operation of a plant according to FIG. 2 for the removal of C ₂ to C ₅ aldehydes

This results in a reduction of the Propanalbeladung of 1, 55 kg / h in the gas stream 1 to 8.5 * 10 ^"3 kg / h in Propanal depleted gas stream 4. It is therefore a

 Reduction of propanal loading by 99.45%.

In Table 2, a maximum utilization case of a system is shown, in which case the mass flows and their respective loading with propanal is also shown here.

Table 2: Maximum operation of a plant according to FIG. 2 for the removal of C ₂ to C ₅ aldehydes

Reference numeral mass flow (kg / h) propanal content of Propanalanteil

from FIG. 2 mass flow (kg / h) (kg / kg)

This results in a reduction of the Propanalbeladung of 4.03 kg / h in the gas stream 1 to 0.03 kg / h in the propanal depleted gas stream 4. So it is a

 Reduction of propanal loading by 99.26% in maximum operation.

Table 3 shows a utilization case of a system in which the

Mass flows and their respective loading with another oxygen-containing organic component of a chain length of C ₂ to C ₇ , wherein butyl acrylate was used as an example, can be seen.

Table 3: Operation of a plant according to FIG. 2 for the removal of other oxygen-containing organic components

Daraus ergibt sich eine Reduzierung der Butylacrylatbeladung von 0,652 kg/h im Gasstrom 1 auf 0,0035 kg/h im Butylacrylat abgereicherten Gasstrom 4. Es handelt sich also um eine Reduzierung der Butylacrylatbeladung um 99,47 %.

This results in a reduction of the butyl acrylate loading from 0.652 kg / h in the gas stream 1 to 0.0035 kg / h in the butyl acrylate-depleted gas stream 4. This therefore represents a reduction of the butyl acrylate loading by 99.47%.

Advantages arising from the invention: by exploiting the resources available anyway in a polyethylene plant, the invention provides an extremely low-cost removal of aldehydes and / or other oxygen-containing organic components from gases. The use of water for absorption saves the installation of additional infrastructure - a process that can be easily integrated into existing plants gszeichenliste gas flow

water

water enriched in aldehydes and / or other oxygen-containing organic components

gas stream depleted in aldehydes and / or other oxygenated organic components

absorption column

desorption column

torch line

natural gas

Partial stream of depleted in aldehydes and / or other oxygenated organic components water

fresh water

depleted in aldehydes and / or other oxygenated organic components

electricity

Claims

claims 1. A process for the removal of C ₂ - to C ₅ -aldehydes and others oxygen-containing organic components having a chain length of C ₂ to C ₇ from a gas stream in a polyethylene plant, wherein  the gas stream is contacted with water in at least one apparatus for effecting absorption and the aldehydes and / or the other oxygen-containing organic components are absorbed by water, with a gas stream depleted in aldehydes and / or other oxygen-containing organic components and aldehydes and / or other oxygen-containing organic components enriched water stream arises, both of which are removed from the at least one apparatus for performing the absorption, and wherein  with aldehydes and / or other oxygen-containing organic  Components enriched water stream is brought into at least one apparatus for performing a desorption with a stripping gas in contact, wherein the aldehydes and / or the other oxygen-containing organic components are washed out and to aldehydes and / or other oxygen-containing organic components submitted water stream and an aldehydes and / or other oxygen-containing organic components enriched stripping gas is formed, both of which are discharged from the at least one apparatus for performing the desorption, characterized in that  as stripping gas in the at least one apparatus for carrying out the desorption different fuel gases of various compounds of elements C or H or mixtures thereof, preferably natural gas, are used and the enriched with aldehydes and / or other oxygen-containing organic components stripping gas is passed directly to a torch, in which it is burned. 2. The method according to claim 1, characterized in that the absorption in the at least one apparatus for performing the absorption in a temperature range of 20 ° C to 50 ° C, and preferably in a temperature range of 35 ° C to 40 ° C, performed becomes. 3. The method according to any one of claims 1 or 2, characterized in that the absorption in the at least one apparatus for performing the absorption in a pressure range of 10 to 50 bar, and preferably in a pressure range of 20 to 40 bar, is performed. 4. Process according to one of claims 1 to 3, characterized in that the aldehydes to be removed are propanal. 5. The method according to any one of claims 1 to 4, characterized in that it is in the other oxygen-containing organic components  Butyl acrylate is. 6. The method according to claim 6, characterized in that the torch in a pressure range of 1 bar to 3 bar abs. is operated. 7. The method according to any one of claims 6 or 7, characterized in that a partial stream of depleted in aldehydes and / or other oxygen-containing organic components water stream is passed into the at least one apparatus for performing the absorption, in which it is used again for absorption and another substream of the depleted in aldehydes and / or other oxygenated organic components water stream is discharged from the process. 8. The method according to any one of claims 6 to 8, characterized in that in the at least one apparatus for performing the desorption fresh water is introduced, having a temperature of 0 ° C to 120 ° C, and preferably from 80 ° C to 100 ° C has. 9. The method according to claim 9, characterized in that as fresh water from the polyethylene production resulting condensate is used. 10. The method according to any one of claims 6 to 11, characterized in that the volume flow of the stripping gas at the inlet in the at least one  apparatus for carrying out the desorption via a  Control device is kept constant. 11. Device for the removal of C ₂ - to C ₅ -aldehydes and others oxygen-containing organic components having a chain length of C ₂ to C ₇ from a gas stream in a polyethylene plant according to the method of claim 1, comprising at least one apparatus for carrying out an absorption, which has a feed line for water at the top end and a discharge line for water enriched in aldehydes and / or other oxygen-containing organic components and which at the lower end has a feed line for aldehydes and / or or other oxygen-containing organic components enriched gas and at the top of a derivative for  Aldehydes and / or other oxygen-containing organic components secured gas and a transfer is provided, through which enriched in aldehydes and / or other oxygen-containing organic components water from the at least one apparatus for performing the absorption in fluid-conducting compound with an at least an apparatus for performing a desorption is, wherein the at least one apparatus for performing the desorption comprises a supply line for enriched in aldehydes and / or other oxygen-containing organic components water at the head and at the bottom of a derivative for aldehydes and / or at others  depleted water is provided oxygen-containing organic components, and wherein at the lower end a supply line for fuel gas is provided, which rises in the at least one apparatus for performing the desorption upwards and at the head end a discharge is provided which opens into a torch. 12. The device according to claims 11, characterized in that the derivative of the aldehydes and / or other oxygen-containing organic  Components of depleted water from the at least one apparatus for performing the desorption as a partial flow into the top of the at least one apparatus for performing the absorption opens. 13. Device according to one of claims 1 1 or 12, characterized in that a separate water supply to the at least one apparatus for performing the desorption is provided. 14. Device according to one of claims 11 to 13, characterized in that the at least one apparatus for carrying out the desorption is carried out as a desorption column or as a spray tower. 15. Device according to one of claims 11 to 14, characterized in that the at least one apparatus for carrying out the absorption as an absorption column or as a bubble column is executed. 16. Device according to one of claims 11 to 15, characterized in that the at least one apparatus for performing the desorption is provided with a control device for controlling the volume flow of the fuel gas.