EP4176218A1

EP4176218A1 - Gas mixture separation apparatus and method for separating at least one main fluid from a gas mixture

Info

Publication number: EP4176218A1
Application number: EP21740001.9A
Authority: EP
Inventors: Christian Blank
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-07-02
Filing date: 2021-07-01
Publication date: 2023-05-10
Also published as: DE102021117030B4; DE102021117030A1; WO2022003128A1

Abstract

The invention relates to gas mixture separation apparatus for separating a main fluid, having a start block (12) and an end block (16). The start block (12) has a first heat exchanger (22) and a second heat exchanger (28). Furthermore, a return line (24) is provided for the main fluid separated out in the end block (16), which is operatively coupled to the first heat exchanger (54) of the end block (16) and the first heat exchanger (22) of the start block (12), so that the main fluid draws heat from a process fluid present in the first heat exchanger (22, 54) to cool the process fluid. The second heat exchanger (28) is coupled to a line (32) through which it receives a cooling fluid. The second heat exchanger (28) condenses a separating fluid of a process fluid and separates the separating fluid out. A third heat exchanger (40), separated from the return line, provides for a heat exchange between the process fluid fed to the first heat exchanger (22) of the start block (12) and the separating fluid. Furthermore, a method for separating at least one main fluid from a gas mixture is described.

Description

Gas mixture separation plant and method for separating at least one main fluid from a gas mixture

The invention relates to a gas mixture separation system for separating at least one main fluid from a gas mixture. The invention also relates to a method for separating at least one main fluid from a gas mixture.

In view of a future increased demand for hydrogen, especially in the mobility sector, and the goal of an energy turnaround from regenerative raw materials with the simultaneous progressive expansion of regenerative electricity production, the storage of hydrogen for further use is a major challenge for the next few years Separation of the pure hydrogen contained in a gas mixture.

Currently, pure hydrogen is mainly produced by steam reforming natural gas, with the harmful gases still remaining in the product gas for a fuel cell, for example carbon monoxide, carbon dioxide and residues of methane, having to be laboriously separated out.

From DE 102018 103203 A1, for example, a method for breaking down air by means of membranes is known, which is also referred to as membrane method. However, this method is relatively expensive.

In addition, the so-called Linde method is still a common method for breaking down gas mixtures, especially air. However, this method is relatively energy-intensive, which is why the energy efficiency of the method is disadvantageous.

The object of the invention is to provide a gas mixture separation plant and a corresponding method with which it is possible to separate a desired fluid from a gas mixture in an energy-efficient manner. The object is achieved according to the invention by a gas mixture separation system for separating at least one main fluid from a gas mixture, the gas mixture separation system comprising an initial block and an end block, which is connected downstream of the initial block. The initial block comprises an inlet for the gas mixture, a compressor connected downstream of the inlet for compressing the gas mixture, a first heat exchanger, a second heat exchanger and an outlet. The end block includes an inlet, a first heat exchanger and an outlet. The inlet of the end block is fluidly connected to the outlet of the header. The gas mixture separation plant has a return line for a main fluid separated in the end block, which is flow-connected to the outlet of the end block. The return line is functionally coupled both to the first heat exchanger of the end block and to the first heat exchanger of the initial block, so that the main fluid present in the return line withdraws heat from a process fluid present in the respective first heat exchanger in order to cool the corresponding process fluid. The second heat exchanger of the header is connected downstream of the first heat exchanger of the header. The second heat exchanger of the initial block liquefies and separates a separation fluid from a process fluid which has been received from the associated first heat exchanger. The second heat exchanger of the header is coupled to a line via which the second heat exchanger of the header receives a cooling fluid that extracts heat from the process fluid present in the second heat exchanger of the header in order to cool the corresponding process fluid. The header has a third heat exchanger that ensures a heat exchange between the respective process fluid that is supplied to the first heat exchanger of the header and the separation fluid that has been separated from the process fluid by means of the second heat exchanger of the header, so that the separation fluid removes heat from the process fluid and evaporates. The third heat exchanger of the initial block is separated from the return line.

Furthermore, the object is achieved according to the invention by a method for separating at least one main fluid from a gas mixture, with the following steps:

Providing a gas mixture, Compressing the gas mixture to provide a process fluid,

Forwarding the process fluid into a first heat exchanger of a header,

Forwarding the process fluid into a second heat exchanger of the initial block, which is connected downstream of the first heat exchanger,

Liquefaction and separation of a separation fluid in the second heat exchanger of the initial block,

Forwarding the process fluid from the second heat exchanger of the initial block to a first heat exchanger of an end block,

Returning a main fluid separated in the end block through the first heat exchanger of the end block by means of a return line, so that a heat exchange takes place between the process fluid present in the first heat exchanger of the end block and the main fluid,

Forwarding of the separation fluid separated in the second heat exchanger of the header to a third heat exchanger of the header, which ensures a heat exchange between the respective process fluid that is fed to the first heat exchanger of the header and the separation fluid that has been separated from the process fluid by means of the second heat exchanger of the header , so that the separation fluid removes heat from the process fluid and vaporizes it, the third heat exchanger of the initial block being separated from the return line, and

Returning the main fluid separated in the end block through the first heat exchanger of the start block by means of the return line, so that a heat exchange takes place between the process fluid present in the first heat exchanger of the start block and the main fluid.

With the gas mixture separation system, in particular the appropriately arranged heat exchangers and the return of the main fluid separated in the end block through the respective first heat exchanger, energy-efficient extraction of the main fluid from the gas mixture is ensured. The main fluid can in principle be hydrogen, which is present in as pure as possible is present, since hydrogen as the main gas for a hydrogen economy is to be split off from the gas mixture in as pure a form as possible. For this purpose, a separation fluid has been separated from the gas mixture in the second heat exchanger of the initial block, this being liquefied beforehand. The separation fluid can be a further component of the gas mixture that is to be separated from the gas mixture in order to be able to provide the pure hydrogen. In this respect, the separation fluid can be carbon monoxide, carbon dioxide or methane.

The process fluid in the second heat exchanger of the initial block can be cooled in order to liquefy the separation fluid and thus to separate it in a simple manner from the process fluid present in the second heat exchanger. For this purpose, the cooling fluid is fed to the second heat exchanger, which interacts accordingly with the process gas in the second heat exchanger, whereby the separation fluid can be liquefied in order to be able to separate it accordingly. The cooling fluid can be cooled nitrogen and / or cooled oxygen, the cooling fluid being, for example, at a temperature between 70 and 110 Kelvin, in particular at 95 Kelvin or lower.

In this respect, the gas mixture separation system can comprise at least one cooling fluid line or a line through which the cooling fluid flows. The cooling fluid can have a correspondingly low temperature, for example a temperature between 70 and 110 Kelvin, in particular a temperature of 95 Kelvin or lower, preferably 92 Kelvin or lower. The cooling fluid thermally couples with the respective process fluid in the at least one second heat exchanger, in particular in all existing second heat exchangers, whereby the corresponding separation fluid liquefies and can thus be separated from the respective process fluid.

In particular, the gas mixture separation system can comprise two cooling fluid lines or two lines through which two different cooling fluids flow separately from one another. In this way, thermal coupling with the two different cooling fluids can take place in the respective second heat exchanger.

The at least one cooling fluid can be nitrogen and / or oxygen. The at least one cooling fluid line or the line through which the cooling fluid flows can be part of a further separation system, for example an air separation system, which is thus thermally coupled to the gas mixture separation system.

Accordingly, a system can be provided that includes the gas mixture separation system and the further separation system, the gas mixture separation system and the separation system being thermally coupled via the at least one cooling fluid line or the line through which the cooling fluid flows.

The further decomposition plant can be part of a system for storing hydrogen obtained from coal.

In other words, it is ensured in the second heat exchanger of the initial block that the cooling fluid interacts with the process fluid in the second heat exchanger that has been fed to the second heat exchanger. As a result, energy or heat is withdrawn from this process fluid, so that the separation fluid can be liquefied and separated from the process fluid that has been fed to the second heat exchanger.

Basically, the process fluid fed to the second heat exchanger corresponds to the separation fluid and the process fluid that leaves the second heat exchanger. In this respect, the cooling fluid removes energy or heat from the separation fluid and the process fluid, which leaves the second heat exchanger.

Due to the third heat exchanger, the separation fluid previously liquefied by means of the second heat exchanger of the initial block can be evaporated again, as a result of which it withdraws heat from the process fluid present in the third heat exchanger of the initial block. The energy efficiency of the gas mixture separation system can thus be further improved. The corresponding separation fluid is then in the form of a gas.

The third heat exchanger of the initial block is separated from the return line so that the main fluid which flows through the return line does not interact with another fluid in the third heat exchanger. Rather, in the third heat exchanger there is only an exchange of heat between the process fluid that is fed to the first heat exchanger of the initial block and the separation fluid that has been separated from the process fluid that was fed to the second heat exchanger by means of the second heat exchanger of the initial block.

The gas mixture, which is compressed or compressed in the compressor of the initial block, can be compressed to a pressure <5 bar, whereby the boiling point of the individual gases of the gas mixture is increased accordingly.

In principle, thermal energy is withdrawn from the corresponding process fluid in the respective heat exchangers, as a result of which the process fluid is cooled. For this purpose, the main fluid that is cooled to the maximum is used in particular, which has been split off in the end block in order to cool the process fluid present in the first heat exchanger of the initial block. As a result, the energy efficiency of the entire gas mixture separation system can be increased accordingly.

The gas mixture separation plant can be used in a system for storing hydrogen obtained from coal, which system has a coal gasification reactor for gasifying coal. The coal gasification reactor requires pure oxygen for the gasification process, which can be provided as the main fluid of the gas mixture separation plant or as a separation fluid for the gas mixture separation plant.

In principle, the gas mixture separation plant can therefore be integrated in a system for storing hydrogen obtained from coal, which has a coal gasification reactor for gasifying the coal and a steam power plant for producing electricity, which is thermally coupled to the coal gasification reactor. The system can also have a water-gas shift reaction plant which is connected to the coal gasification reactor in order to receive the reaction gases from the coal gasification reactor, a discharge line coupled to an output of the water gas shift reaction system, which is thermally coupled to a feed water line of the steam power plant and a Include gas storage. The gas store can be connected to the water-gas shift reaction system in order to store at least one of the product gases of the water-gas shift reaction system, the steam power plant for Electricity production is thermally coupled with the coal gasification reactor in such a way that the reaction gases of the coal gasification reactor are sufficiently cooled due to the heat dissipated to the feed water of a feed water line of the steam power plant, so that the reaction gases can be processed directly in the water gas shift reaction system without active cooling in between. The gas mixture separation plant can itself provide pure hydrogen, for example as the main fluid, wherein the pure hydrogen can be (temporarily) stored together with the hydrogen obtained from the water-gas shift reaction plant. In addition, the gas mixture separation plant can provide pure oxygen, for example as a separation fluid, which is fed to the coal gasification reactor for the gasification process.

If, for example, pure oxygen is required or has to be stored anyway, the gas mixture separation system according to the invention can decompose a gas mixture with a significantly reduced energy requirement compared to the conventional methods, in particular a hydrogen-rich gas mixture. This is because the cooled individual gases that are already present are used exclusively by means of thermal coupling in order to liquefy a separation fluid from the process fluid or process gas, which lowers the temperature of the process fluid.

One aspect provides that the end block has a second heat exchanger, wherein the second heat exchanger of the end block is connected downstream of the first heat exchanger of the end block, and wherein the second heat exchanger of the end block liquefies a separation fluid of a process fluid obtained from the associated first heat exchanger and separates it from the process fluid. The second heat exchanger of the end block is coupled to the line via which the second heat exchanger of the end block receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger of the end block in order to cool the corresponding process fluid. As a result, the energy efficiency of the gas mixture separation system and of the method can be increased accordingly, since the process fluid is also processed in two different heat exchangers in the end block in order to reduce the temperature of the process fluid accordingly. In this respect, there is a thermal coupling in both heat exchangers of the end block and in both second heat exchangers of the beginning and end blocks, for example with the Main fluid or the cooling fluid, whereby the corresponding process fluid is cooled.

In principle, several separation fluids can thus be withdrawn from the process fluid, which are liquefied beforehand and then split off. This can ensure that the main fluid is pure hydrogen.

Since separation fluids are withdrawn from the process fluid that is processed by the gas mixture separation system, the composition of the process fluid changes accordingly. Thus, the process fluid upstream of the second heat exchanger of the initial block also comprises at least one further gas or a further component of the gas mixture than the process fluid that is fed to the second heat exchanger of the end block.

Another aspect provides that the end block has a third heat exchanger which ensures a heat exchange between the respective process fluid that is supplied to the first heat exchanger of the end block and the separation fluid that has been separated from the process fluid by means of the second heat exchanger of the end block, so that the separation fluid removes heat from the process fluid and vaporizes it. In particular, the third heat exchanger of the end block is also separated from the return line. The separation fluid previously liquefied by means of the second heat exchanger of the end block can thus be evaporated again, as a result of which it withdraws heat from the process fluid present in the third heat exchanger of the end block. The energy efficiency of the gas mixture separation system can thus be further improved. The corresponding separation fluid is thus in the form of a gas.

According to a further aspect, at least one middle block is provided between the header and the end block, the middle block comprising an inlet, a first heat exchanger and an outlet, the inlet of the middle block with the outlet of the header and the outlet of the middle block with the inlet of the end block are connected, and wherein the return line is also functionally coupled to the first heat exchanger of the central block, so that the main fluid present in the return line withdraws heat from a process fluid present in the first heat exchanger of the central block in order to cool the corresponding process fluid. With the middle block, further cooling of the process fluid can take place, since the Central block comprises a further first heat exchanger which ensures a heat exchange between the main fluid separated in the end block, which is returned via the return line, and the process fluid present in the first heat exchanger of the central block. In this respect, there is a further thermal coupling.

In principle, every heat exchanger in the entire gas mixture separation system ensures a thermal coupling, via which heat is extracted from the process fluid in order to cool it further.

The corresponding heat extraction can take place in the case of the respective second heat exchanger by means of the cooling fluid, in the case of the respective first heat exchanger by means of the main fluid or in the case of the respective third heat exchanger by means of the respective separation fluid.

In particular, the central block has a second heat exchanger, the second heat exchanger of the central block being connected downstream of the first heat exchanger of the central block, and the second heat exchanger of the central block liquefying a separation fluid of a process fluid obtained from the first heat exchanger of the central block and separating it from the process fluid. The second heat exchanger of the central block is coupled to the line via which the second heat exchanger of the central block receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger of the central block in order to cool the corresponding process fluid. The process fluid can thus also be cooled several times in the central block by the central block having at least a second heat exchanger which ensures heat exchange between the process fluid and the cooling fluid, via which the corresponding separation fluid can be liquefied and separated. Correspondingly, heat can be extracted from the process fluid by the cooling fluid. In addition, this ensures that the main fluid obtained from the gas mixture is present in as pure a form as possible, since several separation fluids have been split off from the gas mixture, in particular before they were liquefied.

The separation fluid to be separated is basically liquefied in that there is a thermal coupling in the corresponding second heat exchanger of the blocks of the gas mixture separation plant between the process fluid and the cooling fluid. In principle, the gas mixture separation plant can comprise a plurality of middle blocks, which are each arranged one after the other between the start block and the end block, the respective middle blocks being coupled to one another. In this way, the purity of the main fluid can be ensured, since several separation fluids have been separated from the gas mixture, in particular one separation fluid per additional central block. In this respect, the number of central blocks determines how many different separation fluids are separated from the gas mixture.

The number of middle blocks also ensures how often the process fluid is cooled or how often the main fluid separated in the end block carries out a heat exchange with the process fluid in the corresponding blocks, i.e. the start block, the several middle blocks and the end block.

The gas mixture separation system can have a modular structure so that the number of central blocks can be selected to be variable, namely between 0 and a desired number. The higher the number of central blocks, the more different parts of the gas mixture can be separated.

Another aspect provides that a first central block and a second central block are provided between the initial block and the end block, the first central block comprising an inlet, a first heat exchanger and an outlet. The second central block comprises an inlet, a first heat exchanger and an outlet. The input of the first middle block is connected to the output of the header, the output of the first middle block is connected to the input of the second middle block, and the output of the second middle block is connected to the input of the end block. The return line is also functionally coupled to the first heat exchanger of the first central block and to the first heat exchanger of the second central block, so that the main fluid present in the return line extracts heat from a process fluid present in the first heat exchanger of the first central block and from a process fluid present in the first heat exchanger of the second central block to cool the corresponding process fluid. The energy efficiency of the gas mixture separation plant is accordingly increased, since the Main fluid is used several times for cooling the process fluid, namely additionally in the two central blocks.

In particular, the first central block and the second central block each have a second heat exchanger, wherein the second heat exchanger of the first central block is connected downstream of the first heat exchanger of the first central block, and wherein the second heat exchanger of the first central block liquefies a process fluid contained in the first heat exchanger of the first central block and separated from the process fluid, wherein the second heat exchanger of the first central block is coupled to the line via which the second heat exchanger of the first central block receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger of the first central block in order to cool the corresponding process fluid, and wherein the second heat exchanger of the second central block is connected downstream of the first heat exchanger of the second central block, and wherein the second heat exchanger of the second central block is a separation fluid of one of the first heat exchanger of the second central block ks contained process fluids liquefied and separated from the process fluid, wherein the second heat exchanger of the second central block is coupled to the line via which the second heat exchanger of the second central block receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger of the second central block in order to generate the corresponding To cool process fluid. The efficiency is further increased, since a separating fluid is liquefied and separated in the respective second heat exchangers of the two central blocks, in that the cooling fluid is supplied to the respective second heat exchanger, whereby heat is extracted from the corresponding process fluid. In addition, the purity of the main fluid can be improved accordingly, since more separation fluids are separated from the process fluid.

In principle, the second heat exchangers of the different blocks can interact with the cooling fluid, whereby the separation fluid to be separated in the second heat exchanger is liquefied so that the separation fluid can be separated from the process fluid present.

Furthermore, the respective middle block can have a third heat exchanger which ensures a heat exchange between the respective process fluid that is supplied to the first heat exchanger and the separation fluid that is generated by means of the respective second heat exchanger has been separated from the process fluid, so that the separation fluid removes heat from the process fluid and evaporates.

The middle block can also comprise a third heat exchanger which - in a manner analogous to the start block or the end block - ensures a heat exchange between the respective process fluid that is fed to the first heat exchanger of the middle block and the separation fluid. The separation fluid has been separated from the process fluid in the second heat exchanger by means of the respective second heat exchanger after this has previously been liquefied. The separation fluid removes heat or energy from the process fluid, so that the liquid separation fluid evaporates again. In this respect, the energy efficiency of the gas mixture separation system can be increased further.

According to a further aspect, the second heat exchanger is fluidically coupled to the associated heat exchanger in such a way that the respective separation fluid in the first heat exchanger interacts with the corresponding process fluid in order to extract heat from the process fluid. The energy efficiency of the gas mixture separation system can thus be increased further.

Another aspect provides that at least one storage device is provided for storing the main fluid. The hydrogen, in particular pure hydrogen, can at least be temporarily stored in the store for further use.

Alternatively or in addition, a memory for storing the separation fluid can be provided, which has been separated in the respective second heat exchanger in order to store or temporarily store the separation fluid for later use.

Furthermore, it can be provided that the gas mixture separation system has thermal insulation which surrounds and insulates the components of the gas mixture separation system. In particular, the respective heat exchangers and the return line are surrounded by the thermal insulation in order to thermally insulate them accordingly.

Another aspect provides that the initial block has a fourth heat exchanger, which is connected upstream of the third heat exchanger, wherein the fourth heat exchanger ensures a heat exchange between the respective process fluid that is fed to the third heat exchanger of the initial block and the separation fluid that has been separated from the process fluid by means of the second heat exchanger of a block directly downstream of the initial block. In principle, the efficiency of the gas mixture separation system can thus be increased further. In other words, the fluid separated in the second heat exchanger is thermally coupled via the fourth heat exchanger to the compressed gas mixture which is fed to the first heat exchanger of the initial block.

The block directly downstream can be the end block if no middle block is provided or the (first) middle block if at least one middle block is provided between the start block and the end block.

Furthermore, each block that has a directly downstream block can have a corresponding fourth heat exchanger, that is to say all blocks except the end block, which this has no block directly downstream. This can further increase the efficiency of the entire gas mixture separation plant.

The respective fourth heat exchanger is also separated from the return line, i.e. the respective fourth heat exchanger does not receive the main fluid that flows through the main line.

In general, the respective third heat exchanger of the corresponding block, i.e. that of the start block, the middle block or the end block, is separated from the return line so that the main fluid flowing through the return line does not interact with another fluid in the third heat exchanger.

Rather, in the corresponding third heat exchanger there is only an exchange of heat between the process fluid that is fed to the first heat exchanger of the respective block and the separation fluid that has been separated from the process fluid that was fed to the second heat exchanger by means of the second heat exchanger of the corresponding block.

Basically, the blocks are graded according to the temperature of the separation fluids to be separated and the temperature point at which the Physical state changes to liquid. The separating fluids to be separated off at high temperatures are thus split off earlier, that is closer to the initial block, whereas the separating fluids still to be separated off at lower temperatures are split off later, i.e. closer to the end block.

Initially, in the end block, the cooled separation fluids of the gas mixture separation plant are separated from the respective process fluid and thermally coupled with the last gas mixture by means of a heat exchanger and liquefied by cooling with the cooling fluid, e.g. carbon monoxide. The main fluid, which can also be referred to as residual gas, for example hydrogen, can thus be passed in gaseous form to the central or initial block with maximum cooling.

The corresponding separation fluid, for example liquefied carbon monoxide, cools the process fluid in the supply line from the central or initial block by means of evaporation and expansion including heat transfer.

As already explained, the maximally cooled main fluid, that is to say the maximally cooled gaseous hydrogen, can be used to cool the supplied process fluid from the central or initial block.

In principle, the temperature of the corresponding separation fluid and of the process fluid in the central block is somewhat higher, the temperature of the change in the state of aggregation of the separation fluid in the central block is also higher.

Each block can comprise several thermal couplings, namely a heat exchanger between the process fluid and the ultimately separated or remaining main fluid (the respective first heat exchanger), a thermal coupling for cooling the process fluid with the already cooled separation fluids (the respective second heat exchanger) and a thermal coupling of the liquid separated in the respective block, which also cools the process fluid by means of evaporation and normal pressure (the respective third heat exchanger).

Further advantages and properties of the invention emerge from the following description and the drawings, to which reference is made. In the drawings show: Figure 1 shows a schematic structure of an inventive

Gas mixture separation plant according to a first embodiment,

Figure 2 shows a schematic structure of an inventive

Gas mixture separation plant according to a second embodiment, and

Figure 3 shows a schematic structure of an inventive

Gas mixture separation plant according to a third embodiment.

In FIG. 1, a gas mixture separation plant 10 is shown, which comprises an initial block 12, a middle block 14 downstream of the beginning block 12 and an end block 16 downstream of the middle block 14.

The middle block 14 is thus arranged between the start block 12 and the end block 16.

The starting block 12 has an inlet 18 in the form of a feed line, via which the gas mixture separation system 10 is supplied with a gas mixture which is to be correspondingly broken down in the gas mixture separation system 10. The gas mixture can comprise hydrogen, carbon dioxide, carbon monoxide and nitrogen.

Furthermore, the header 18 comprises a compressor 20, which compresses the gas mixture received via the inlet 18, as a result of which a process fluid is generated. For this purpose, the process fluid can be brought to a pressure of at least 5.2 bar.

The process fluid is transported from the compressor 20 to a first heat exchanger 22 in that the process _fluid interacts with a main fluid separated in the gas mixture separation system 10 at the temperature T 2.i, for example hydrogen. The main fluid removes heat from the process fluid of the header 12, as will be explained in detail below.

The main fluid is conducted via a return line 24 of the gas mixture separation system 10 from the end block 16 via the middle block 14 and the beginning block 12 to a storage unit 26 in which the pure main fluid is stored. In addition, the starting block 12 comprises a second heat exchanger 28, which is connected downstream of the first heat exchanger 22, so that the second heat exchanger 28 receives the process fluid that is correspondingly cooled in the first heat exchanger 22.

The second heat exchanger 28, in particular the process fluid processed by the second heat exchanger 28, also interacts at the temperature T _2. o with at least one cooling fluid 30, for example nitrogen and / or oxygen, which flows via a feed line 31 through a line 32 to a discharge line 33 . The line 32 can accordingly also be referred to as a cooling fluid line through which the cooling fluid 30 flows.

The gas mixture separation plant 10 can in principle also comprise two or more lines 30 through which two or more different cooling fluids 30 flow separately from one another, for example nitrogen and oxygen.

The at least one cooling fluid 30 can be provided by a separate system, this being provided for storage or further use. The at least one line 30 through which the cooling fluid flows is, for example, part of a further separation plant, in particular an air separation plant. This further decomposition plant is thus thermally coupled to the gas mixture decomposition plant 10.

In other words, the gas mixture decomposition plant 10 and the further decomposition plant together form a system, in particular the further decomposition plant can be part of a system for storing hydrogen obtained from coal. In this respect, the gas mixture separation system 10 can also be part of the system for storing hydrogen obtained from coal.

The cooling fluid 30 flowing in the at least one line 32 couples thermally with the respective process fluid in the second heat exchanger 28.

This increases the temperature of the cooling fluid 30 in the second heat exchanger 28 of the initial block 12 to a temperature T ₂₀ , which the cooling fluid 30 also has in the discharge line 33. The corresponding cooling fluid 30, which flows through the line 32, ensures that a separation fluid 34 is liquefied in the second heat exchanger 28 of the initial block 12 at the temperature T2.0, whereby this can be separated from the process fluid in the second heat exchanger 28, as by the corresponding arrow is shown in FIG.

The separation fluid 34, for example carbon dioxide, is liquefied at the temperature T2.0 in that the process fluid is thermally coupled to the at least one cooling fluid at the temperature T1.0. The liquefied separation fluid 34 can then be driven further by means of a pump.

The process fluid is passed on from the second heat exchanger 28 to the outlet 36 of the initial block 12, which is in flow connection with the inlet 38 of the subsequent central block 14.

The separation fluid 34 separated off in the second heat exchanger 28 of the initial block 12 can flow through a third heat exchanger 40, which is shown in dashed lines in FIG.

In the third heat exchanger 40, a heat exchange takes place at the temperature T2.2 between the liquefied separation fluid 34, for example carbon dioxide, and the process fluid present before it is fed to the first heat exchanger 22. Here, heat can already be extracted from the process fluid, as a result of which the previously liquid separation fluid 34 evaporates again.

In this respect, the separation fluid 34 is present as a gas with the temperature T _2.2 .

The process fluid, which has been supplied via the inlet 38 of the central block 14, is passed in the central block 14 in an analogous manner to the initial block 12 to a first heat exchanger 42 of the central block 14, in which the process fluid is thermally combined with the main fluid at the temperature T 1 .1 interacts, which has been passed through the return line 24. The process fluid is accordingly cooled via the main fluid in the first heat exchanger 42 of the central block 14.

The cooled process fluid leaving the first heat exchanger 42 of the central block 14 is sent to a second heat exchanger 44 of the Central block 14 supplied, which also _{receives the cooling fluid 30 at the temperature Ti .0} , which flows through the cooling line 32.

This liquefies a further separation fluid 46 of the process fluid, which is present in the second heat exchanger 44 of the central block 14, so that the further separation fluid 46 can be separated in the second heat exchanger 44 of the central block 14, as shown by the corresponding arrow in FIG. The further separation fluid 46 is, for example, carbon monoxide. Liquefaction of further Abtrennfluids 46 is carried at the temperature Ti. _0th

The remaining process fluid is fed to an input 50 of the end block 16 via an output 48 of the central block 14.

The separation fluid 46 separated in the second heat exchanger 44 of the central block 14, which is liquid, is fed to an (optional) third heat exchanger 52 of the central block 14 in a manner analogous to the initial block 12, for example by means of a pump. The third heat exchanger 52 of the central block 14 enables a heat exchange between the liquid separation fluid 46 and the process fluid which is supplied to the first heat exchanger 42 of the central block 14. In this case, the liquid separation fluid can extract heat from the process fluid in that the separation fluid 46 is evaporated. This happens at the temperature Ti. ₂ .

The process fluid fed to the end block 16 is also fed to a first heat exchanger 54 in the end block 16, which enables a heat exchange between the corresponding process _fluid and the main fluid at the temperature T 0.i, the main fluid being fed via the return line 24 from the end block 16 to the reservoir 26 will. Here, the corresponding process fluid can be cooled by the main fluid.

The process fluid coming from the first heat exchanger 54 of the end block 16 is fed to a second heat exchanger 56 of the end block 16, in which the process fluid is mixed with the cooling fluid 30 at the temperature To _. o interacts so that a further separation fluid 58, for example nitrogen, is liquefied from the present process fluid. The further separation fluid 58 can so in second heat exchanger 56 of the end block 16 are separated, as shown by the corresponding arrow in FIG.

The separation fluid 58 is fed to an (optional) third heat exchanger 60 of the end block 16, in particular by means of a pump. The third heat exchanger 60 of the end block 16 also receives the process fluid that is to be supplied to the first heat exchanger 54 of the end block 16. This makes it possible for the further separation fluid 58, which has previously been liquefied, to be evaporated again, as a result of which it withdraws heat from the process fluid. This happens at the temperature T _0.2 .

The process fluid leaving the second heat exchanger 56 is fed via an outlet 62 of the end block 16 into the return line 24, which interacts with the respective first heat exchangers 22, 42, 54 of the corresponding blocks 12, 14 and 16 in order to cool the process fluid present there. The process fluid leaving the second heat exchanger 56 thus corresponds to the main fluid, which is present in pure form.

In principle, four different gases are separated from the gas mixture in the gas mixture separation plant 10 according to the embodiment according to FIG interacts to extract heat from it.

Furthermore, a further separation fluid 34, 46, 58 is separated in each block 12 to 16, for example carbon dioxide in the initial block 12, carbon monoxide in the middle block 14 and nitrogen in the end block 16.

The separation fluids 34, 46, 58, which are present as gases due to the respective third heat exchangers 40, 52, 60 of the blocks 12-16, can each be at least temporarily stored in a separate memory 64 to 68.

Optionally, it can be provided that the corresponding vaporized separation fluids 34, 46, 58 first interact again with the corresponding process fluid in a fourth heat exchanger or the respective first heat exchanger 22, 42, 54 in order to extract further heat from the process fluid before the corresponding separation fluids 34, 46, 58 are stored in the associated memories 64, 66 and 68. The use of fourth heat exchangers is shown by way of example in FIG. 3, to which reference is made below.

If more than three separation fluids 34, 46, 58 are to be removed from the gas mixture in order to improve the purity of the main fluid, the gas mixture separation plant 10 can have further middle blocks 14, which are provided in an analogous manner between the start block 12 and the end block 16.

In Figure 2, an alternative embodiment is shown in which the central block 14 is not provided.

In this respect, the gas mixture is broken down into three components, namely the main fluid and two separation fluids 34, 58, which were separated from the corresponding process fluid in the respective second heat exchangers 28 and 56 of the starting block 12 and the end block 16, respectively.

Otherwise, the mode of operation of the two gas mixture separation systems according to FIGS. 1 and 2 is the same.

In principle, thermal insulation can be provided which surrounds the components of the gas mixture separation system 10 and thus insulates them.

In FIG. 3, an embodiment of the gas mixture separation plant 10 is shown, which is based on that of FIG.

The embodiment shown in FIG. 3 comprises, in addition to the embodiment according to FIG. 1, a fourth heat exchanger 70 within the initial block 12.

The fourth heat exchanger 70 is connected upstream of the third heat exchanger 40 of the corresponding block, that is to say of the initial block 12, so that the fourth heat exchanger 70 receives the process fluid supplied to the third heat exchanger 40 and the separation fluid 46, which by means of the second heat exchanger 44 of the corresponding block, ie the initial block 12, the block directly downstream has been separated from the process fluid, so the middle block 14. The fourth heat exchanger 70 thus provides a heat exchange between the respective process fluid, that is, that which is supplied to the third heat exchanger 40, and the separation fluid 46 which has been separated in the second heat exchanger 44 of the central block 14.

In principle, the central block 14 can also have a fourth heat exchanger, which is not shown here for reasons of simplicity. The fourth heat exchanger of the middle block 14 would accordingly receive the process fluid fed to the third heat exchanger 52 of the middle block 14 and the separation fluid 58 which has been separated in the second heat exchanger 56 of the end block 16.

In principle, the efficiency of the entire system can be further increased in this way.

Claims

1. Gas mixture separation plant for separating at least one main fluid from a gas mixture, with an initial block (12) and an end block (16), which is connected downstream of the initial block (12), the initial block (12) having an input (18) for the Gas mixture, a compressor (20) downstream of the inlet (18) for compressing the gas mixture, a first heat exchanger (22), a second heat exchanger (28) and an outlet (36), the end block (16) having an inlet (38) , a first heat exchanger (54) and an outlet (62), the inlet (38) of the end block (16) being in flow connection with the outlet (36) of the initial block (12), the gas mixture separation system (10) having a return line (24) for a main fluid separated in the end block (16) which is flow-connected to the outlet (62) of the end block (16), the return line (24) both to the first heat exchanger (54) of the end block (16) and with the first heat exchanger (22) de s header (12) is functionally coupled so that the main fluid present in the return line (24) withdraws heat from a process fluid present in the respective first heat exchanger (22, 54) in order to cool the corresponding process fluid, the second heat exchanger (28) of the header (12) downstream of the first heat exchanger (22) of the initial block (12), the second heat exchanger (28) of the initial block (12) liquefying a separation fluid (34) of a process fluid obtained from the associated first heat exchanger (22) and separating it from the process fluid, wherein the second heat exchanger (28) of the header (12) is coupled to a line (32) via which the second heat exchanger (28) of the header (12) receives a cooling fluid similar to that in the second heat exchanger (28) of the initial block (12) extracts heat from the process fluid present in order to cool the corresponding process fluid, the initial block (12) having a third heat exchanger (40) which exchanges heat between the respective process fluid that the first heat exchanger (22) des Header (12) is supplied, and the separation fluid (34) ensures that has been separated from the process fluid by means of the second heat exchanger (28) of the header (12), so that the separation fluid (34) removes heat from the process fluid and evaporates, and wherein the third heat exchanger (40) of the initial block (12) is separated from the return line (24).

2. Gas mixture separation plant according to claim 1, characterized in that the end block (16) has a second heat exchanger (56), wherein the second heat exchanger (56) of the end block (16) is connected downstream of the first heat exchanger (54) of the end block (16) is, and wherein the second heat exchanger (56) of the end block (16) liquefies a separation fluid (58) of a process fluid received from the associated first heat exchanger (54) and separates it from the process fluid, the second heat exchanger (56) of the end block (16) with the Line (32) is coupled, via which the second heat exchanger (56) of the end block (16) receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger (56) of the end block (16) in order to cool the corresponding process fluid.

3. Gas mixture separation plant according to claim 1 or 2, characterized in that the end block (16) has a third heat exchanger (60) which exchanges heat between the respective process fluid that is fed to the first heat exchanger (54) of the end block (16) , and the separation fluid (58) which has been separated from the process fluid by means of the second heat exchanger (56) of the end block (16), so that the separation fluid (58) removes heat from the process fluid and vaporizes, in particular the third heat exchanger (60) des End blocks (16) is separated from the return line (24).

4. Gas mixture separation plant according to one of the preceding claims, characterized in that between the header (12) and the end block (16) at least one middle block (14) is provided, the middle block (14) comprising an inlet (38), a first heat exchanger (42) and an outlet (48), the inlet (38) of the middle block (14 ) are connected to the outlet (36) of the initial block (12) and the outlet (48) of the central block (14) to the inlet (50) of the end block (16), and the return line (24) additionally to the first heat exchanger ( 42) of the central block (14) is functionally coupled so that the main fluid present in the return line withdraws heat from a process fluid present in the first heat exchanger (42) of the central block (14) in order to cool the corresponding process fluid.

5. Gas mixture separation plant according to claim 4, characterized in that the central block (14) has a second heat exchanger (44), the second heat exchanger (44) of the central block (14) following the first heat exchanger (42) of the central block (14) is switched, and wherein the second heat exchanger (44) of the central block (14) liquefies a separation fluid (46) of a process fluid obtained from the first heat exchanger (42) of the central block (14) and separates it from the process fluid, the second heat exchanger (44) of the central block (14) is coupled to the line (32) via which the second heat exchanger (44) of the central block (14) receives the cooling fluid that extracts heat from the process fluid present in the second heat exchanger (44) of the central block (14) in order to generate the corresponding To cool process fluid.

6. Gas mixture separation plant according to one of claims 1 to 3, characterized in that a first central block (14) and a second central block (14) are provided between the initial block (12) and the end block (16), the first central block ( 14) comprises an inlet (38), a first heat exchanger (42) and an outlet (48), the second central block (14) comprising an inlet (38), a first heat exchanger (42) and an outlet (48), wherein the input (38) of the first central block (14) with the output (36) of the header (12), the output (48) of the first central block (14) with the input (38) of the second central block (14), the output ( 48) of the second central block (14) are connected to the inlet (50) of the end block (16), and wherein the return line (24) is additionally connected to the first heat exchanger (42) of the first central block (14) and to the first heat exchanger (42 ) of the second central block (14) is functionally coupled so that the main fluid present in the return line (24) draws heat from a process fluid present in the first heat exchanger (42) of the first central block (14) and from a process fluid present in the first heat exchanger (42) of the second central block (14) in order to generate the corresponding process fluid to cool.

7. Gas mixture separation plant according to one of claims 4 to 6, characterized in that the respective central block (14) has a third heat exchanger (52) which exchanges heat between the respective process fluid that is fed to the first heat exchanger (42) and the separation fluid (46) which has been separated from the process fluid by means of the respective second heat exchanger (44), so that the separation fluid (46) removes heat from the process fluid and vaporizes it.

8. Gas mixture separation plant according to one of the preceding

Claims, characterized in that in each case the second heat exchanger (28, 44, 56) is fluidically coupled to the assigned first heat exchanger (22, 42, 54) in such a way that the respective separation fluid (34, 46, 58) in the first heat exchanger (22 , 42, 54) interacts with the corresponding process fluid in order to extract heat from the process fluid.

9. Gas mixture separation plant according to one of the preceding

Claims, characterized in that at least one memory (26, 64, 66, 68) is provided for storing the main fluid and / or the separation fluid and / or that thermal insulation is provided which surrounds the components of the gas mixture separation system (10) and insulates.

10. Gas mixture separation plant according to one of the preceding

Claims, characterized in that the initial block (12) has a fourth heat exchanger which is connected upstream of the third heat exchanger (40), the fourth heat exchanger providing a heat exchange between the respective process fluid that is supplied to the third heat exchanger (40) of the initial block (12) and the separation fluid (46, 58) which has been separated from the process fluid by means of the second heat exchanger (56) of a block (14, 16) directly downstream of the initial block (12).

11. A method for separating at least one main fluid from a gas mixture, comprising the following steps: Providing a gas mixture,

Compressing the gas mixture to provide a process fluid,

Forwarding the process fluid into a first heat exchanger (22) of an initial block (12),

Forwarding the process fluid into a second heat exchanger (28) of the initial block (12), which is connected downstream of the first heat exchanger (22),

Liquefying and separating a separation fluid in the second heat exchanger (28) of the initial block (12),

Forwarding the process fluid from the second heat exchanger (28) of the initial block (12) to a first heat exchanger (54) of an end block (16),

Returning a main fluid separated in the end block (16) through the first heat exchanger (54) of the end block (16) by means of a return line (24), so that a heat exchange takes place between the process fluid present in the first heat exchanger (54) of the end block (16) and the main fluid ,

Forwarding of the separation fluid separated in the second heat exchanger (28) of the header (12) to a third heat exchanger (40) of the header (12), which carries out a heat exchange between the respective process fluid that is fed to the first heat exchanger (22) of the header (12) , and the separation fluid (34) which has been separated from the process fluid by means of the second heat exchanger (28) of the initial block (12), so that the separation fluid (34) removes heat from the process fluid and vaporizes, the third heat exchanger (40) of the initial block (12) is separated from the return line (24), and

Returning the main fluid separated in the end block (16) through the first heat exchanger (22) of the initial block (12) by means of the return line (24), so that a heat exchange takes place between the process fluid present in the first heat exchanger (22) of the initial block (12) and the main fluid .