CN101069055B - Systems and methods for cryogenic gas separation - Google Patents

Abstract

Disclosed is a method of gasifying a biomass, comprising heating a fluidized bed reactor loaded with a catalyst represented by Rh/CeO<SUB>2</SUB>/M, where M represents SiO<SUB>2</SUB>, Al<SUB>2</SUB>O<SUB>3 </SUB>or ZrO<SUB>2</SUB>, to temperatures lower than 800 DEG C. introducing biomass particles into the fluidized bed reactor from an upper portion thereof, introducing air and steam into the fluidized bed reactor from a lower portion thereof, and allowing the biomass particles to react at the surface of the Rh/CeO<SUB>2</SUB>/M catalyst so as to manufacture hydrogen and a syngas.

Description

Systems and methods for cryogenic gas separation

priority claim

This application claims the benefit of Russian Patent Application No. 2004128348/06 (030834), filed September 24, 2004, which is incorporated herein by reference in its entirety.

technical field

The present invention relates to gas separation technology, and in particular systems and methods for cryogenic gas separation.

Background technique

Existing methods for the cryogenic separation of target components from gas mixtures are based on freezing of the gas mixture, condensation of the target component, and subsequent separation of the condensate containing the target component from the gas mixture. The freezing of the gas mixture in this method is conventionally carried out at the expense of a throttle valve and expansion of the gas in an expander, or by means of a refrigeration device. In the solution of cryogenic gas separation, recuperators and rectification towers are used as additional auxiliary equipment.

Typical methods for the cryogenic separation of target components from gas mixtures are described, for example, in patents US 6182468B1 and RU 2047061C1. The method of patent US 6182468B1 is based on gas freezing at the expense of throttling of the gas mixture in the Joule-Thompson valve, whereas in patent RU2047061C1 the turbine of the turboexpander is used for gas freezing.

The method of patent US 6182468B1 involves cooling of the mixture, expansion of the mixture without performing mechanical work, partial condensation of the mixture during its expansion, separation of the mixture or a part thereof in a rectification column to obtain liquid and gas phase products. In this case, the cooling of the mixture is carried out using recuperators and chillers, while the mixture is expanded by throttling in the Joule-Thompson valve.

The method of patent RU 2047061C1 consists in cooling the mixture, and separating said mixture into a vapor phase and a liquid phase, a part of the vapor phase is expanded without doing mechanical work, while the other part is expanded by doing mechanical work, separated and expanded in a rectification column mixture to obtain gas and liquid phase products.

The fundamental disadvantages of these cryogenic gas separation bodies are the significant mixture pressure loss and high energy consumption during the cryogenic gas separation process.

Contents of the invention

According to one aspect of the present invention there is provided cooling the mixture, expanding the mixture or a part thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a part thereof in a rectification column to obtain products in liquid and gas phases , wherein the expansion process of the mixture is achieved by passing the mixture through the nozzle channel, thereby swirling the mixture stream in the nozzle channel and/or at the nozzle channel inlet, splitting the mixture stream at the outlet of the nozzle channel or a part thereof at least two streams, one enriched in components heavier than methane and the other deficient in these components; passing the enriched stream partially or fully to a rectification column and allowing The gas phase product obtained in the distillation column is passed partly or completely to the mixture before expansion.

According to an aspect of an embodiment of the present invention, there is provided a process for the separation of a cryogenic gas mixture suitable for separating components of a hydrocarbon gas mixture comprising: cooling the gas mixture; condensing the gas mixture to produce a liquid stream and a gas/vapor; rectifying at least a portion a liquid stream, thereby producing a respective gas phase product; transfer of thermal energy back and forth from at least one of the liquid stream, gas/vapour stream, and gas phase product to at least one other of the gas mixture, liquid stream, gas/vapour stream, gas phase product, and another stream , thereby recycling energy.

In some embodiments, the process further includes expanding and swirling the gas/vapour stream to produce first and second streams, wherein the first stream comprises a gas/vapor stream consisting essentially of heavy components, and the second stream a gas/vapour stream mainly comprising lighter components; and from a liquid stream, a gas/vapour stream, a gas phase product and at least one of said first and second streams to a gas mixture, a liquid stream, a gas/vapour stream, a gas phase The product, the further stream, and at least one other of the first and second streams transfer thermal energy back and forth, thereby recycling the energy.

In some more specific embodiments, the method further comprises rectifying at least a portion of the first stream along with the liquid stream.

In some more specific embodiments, cooling the gas mixture comprises at least partially combining the gas mixture with the liquid stream, gas/vapour stream, gas phase product, said another stream, and said first and second streams. At least a portion of at least one is mixed.

In some more specific embodiments, cooling the gas mixture comprises at least partially transferring from the gas mixture to at least At least a portion of one conducts heat transfer.

In some more specific embodiments, the method further includes compressing at least a portion of the gas phase product.

In some more specific embodiments, the method further includes cooling at least a portion of the gas/vapour stream.

In some more specific embodiments, the method further includes compressing at least a portion of the first stream.

In some more specific embodiments, the method further includes compressing at least a portion of the second stream.

In some more specific embodiments, the method further includes cooling at least a portion of the first stream.

In some more specific embodiments, the method further includes cooling at least a portion of the second stream.

In some more specific embodiments, said thermal energy transfer comprises mixing at least a portion of said at least two streams or streams between which heat is transferred.

In some more specific embodiments, said transfer of thermal energy comprises exchanging thermal energy without mixing at least a portion of said at least two streams or streams between which heat is transferred.

In some more specific embodiments, the method further comprises passing at least a portion of the gas/vapor flow through a turbine.

In some more specific embodiments, the method further includes passing at least a portion of the second stream through a turbine.

In some more specific embodiments, the method further includes condensing at least a portion of the gas phase product.

In some more specific embodiments, the method further comprises further condensing at least a portion of the liquid stream.

In some more specific embodiments, the method further includes condensing at least a portion of the gas/vapour stream.

In some more specific embodiments, the method further includes expanding and swirling at least a portion of the gas phase product.

According to an aspect of an embodiment of the present invention, there is provided a system for the separation of cryogenic gas mixtures suitable for separating components of hydrocarbon gas mixtures, comprising: a first gas/liquid separator for separating an incoming gas mixture into liquid streams and gas/vapor flow; a first expander for producing first and second streams connected to said first gas/liquid separator to receive the gas/vapor flow, the first expander also includes a swirling device for For swirling a gas/vapour stream, thereby separating the heavy components of the gas/vapor stream from the light components of the gas/vapour stream, wherein the heavy components mainly comprise the first stream and the light components mainly comprise the second stream; rectification a tower for producing at least a gas phase product, connected to said first gas/liquid separator to receive a liquid stream; At least one of the two streams transfers thermal energy back and forth to the gas mixture, liquid stream, gas/vapour stream, gas phase product, another stream, and at least one other of the first and second streams, thereby creating Recycle energy.

In some embodiments, the first expander is coupled to a rectification column to provide at least a portion of the first stream to the rectification column.

In some more specific embodiments, the system further includes a first mixer for mixing the incoming gas mixture with a return stream comprising a liquid stream, a gas/vapour stream, a gas phase product, a first and at least a portion of at least one of the second stream and the other stream.

In some more specific embodiments, the system also includes a first compressor that compresses at least a portion of the product in the gaseous phase.

In some more specific embodiments, the system also includes a first compressor that compresses at least a portion of the gas/vapour stream.

In some more specific embodiments, the system also includes a first compressor that compresses at least a portion of the first stream.

In some more specific embodiments, the system also includes a first compressor that compresses at least a portion of the second stream.

In some more specific embodiments, the system also includes a first chiller that cools at least a portion of the first stream.

In some more specific embodiments, the system also includes a first chiller that cools at least a portion of the second stream.

In some more specific embodiments, said thermal energy transfer includes mixing at least a portion of said at least two materials or streams between which heat is transferred.

In some more specific embodiments, said transfer of thermal energy includes exchanging thermal energy without mixing at least a portion of said at least two materials or streams between which heat is transferred.

In some more specific embodiments, the system further includes a turbine for expanding at least a portion of the gas/vapor flow and coupled to the first gas/liquid separator to receive at least a portion of the gas/vapor flow.

In some more specific embodiments, the system further includes a turbine through which at least a portion of the second stream passes, the turbine being coupled to receive at least a portion of the second stream.

In some more specific embodiments, the system further comprises at least one additional gas/liquid separator for separating liquid streams or gas/vapour streams within the system.

In some more specific embodiments, the system further includes another condenser for further condensing at least a portion of the liquid stream.

In some more specific embodiments, the system also includes another condenser for condensing at least a portion of the gas/vapour stream.

In some more specific embodiments, the system also includes another expander for expanding and swirling at least a portion of the gas phase product.

In addition, the following process embodiments are proposed in the following cases: the enriched stream is passed partially or completely to the rectification column, and the gas phase product from the rectification column is partially or completely mixed with the deficient stream; Passing the collection stream partly or completely to the mixture before expansion and partly or completely mixing the gaseous phase products from the rectification column with the starved stream; to the pre-expanded mixture.

Other aspects and features of the invention will become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the invention.

Description of drawings

For a better understanding of the invention, and to show more clearly how it may be put into practice, reference is now made by way of example to the accompanying drawings, which show aspects of embodiments of the invention in which:

Fig. 1 is the schematic diagram of the cryogenic gas mixture separation system of the first embodiment of the present invention;

Figure 2 is a schematic diagram of the cryogenic gas separation device shown in Figure 1;

Fig. 3 is the schematic diagram of the cryogenic gas mixture separation system of the second embodiment of the present invention;

Fig. 4 is the schematic diagram of the cryogenic gas mixture separation system of the third embodiment of the present invention;

Fig. 5 is the schematic diagram of the cryogenic gas mixture separation system of the fourth embodiment of the present invention;

Fig. 6 is the schematic diagram of the cryogenic gas mixture separation system of the fifth embodiment of the present invention;

Fig. 7 is the schematic diagram of the low-temperature gas mixture separation system of the sixth embodiment of the present invention;

8 is a schematic diagram of a low-temperature gas mixture separation system according to a seventh embodiment of the present invention;

9 is a schematic diagram of a low-temperature gas mixture separation system according to an eighth embodiment of the present invention;

10 is a schematic diagram of a low-temperature gas mixture separation system according to the ninth embodiment of the present invention;

11 is a schematic diagram of a low-temperature gas mixture separation system according to the tenth embodiment of the present invention;

Fig. 12 is a schematic diagram of a low-temperature gas mixture separation system according to an eleventh embodiment of the present invention;

13 is a schematic diagram of a low-temperature gas mixture separation system according to a twelfth embodiment of the present invention;

14 is a schematic diagram of a low-temperature gas mixture separation system according to a thirteenth embodiment of the present invention;

Fig. 15 is a schematic diagram of a low-temperature gas mixture separation system according to the fourteenth embodiment of the present invention;

Fig. 16 is a schematic diagram of a low-temperature gas mixture separation system according to the fifteenth embodiment of the present invention;

17 is a schematic diagram of a low-temperature gas mixture separation system according to the sixteenth embodiment of the present invention;

18 is a schematic diagram of a low-temperature gas mixture separation system according to the seventeenth embodiment of the present invention;

Fig. 19 is a schematic diagram of a low-temperature gas mixture separation system of an eighteenth embodiment of the present invention;

20 is a schematic diagram of a low-temperature gas mixture separation system according to the nineteenth embodiment of the present invention;

21 is a schematic diagram of a low-temperature gas mixture separation system according to the twentieth embodiment of the present invention;

22 is a schematic diagram of a low-temperature gas mixture separation system according to the twenty-first embodiment of the present invention;

23 is a schematic diagram of a low-temperature gas mixture separation system according to the twenty-second embodiment of the present invention;

Detailed ways

Some embodiments of the invention can reduce power consumption in LTS facilities. With regard to this aim, according to some embodiments of the invention, it can be achieved in the first embodiment of the invention due to the fact that in the known LTS process for hydrocarbon gas mixtures, it consists of cooling the mixture, without doing mechanical expansion of the mixture or a part thereof, partial condensation of the mixture during its expansion, separation of the mixture or a part thereof in a rectification column to obtain liquid and gas phase products, according to the invention the expansion of the mixture is achieved by passing the mixture through a nozzle channel whereby the mixture stream is swirled in the nozzle channel and/or at the inlet of the nozzle channel, and at the outlet of the nozzle channel or a portion thereof the mixture stream is split into at least two streams, one stream being enriched in methane heavy components, while the other stream is deficient in these components, the enriched stream is passed partly or completely to the rectification column, and the gas phase product obtained in the rectification column is partly or completely passed to the mixture.

Referring to FIG. 1 , there is shown a schematic diagram 200 of a cryogenic gas mixture separation system according to a first embodiment of the present invention, hereinafter referred to as system 200 for brevity. Those skilled in the art will appreciate that system 200 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 200; however, only those shown are representative of those necessary to describe aspects of the present embodiment System 200 of elements.

The system 200 includes a first mixer 30 , a first heat exchanger 32 , a first freezer 34 and a gas/liquid separator 36 respectively connected in series. In some embodiments, the heat exchanger can be used as a freezer. The first mixer 30 includes separate first and second inputs 30a and 30b. The first input 30 a serves as input to the overall system 200 as well as to the first mixer 30 . The second input 30b is used as a return input, the purpose of which will be explained in more detail below. The gas/liquid separator 36 has separate first and second outputs 36a and 36b. The first output 36a is a gas/vapour outlet and the second output 36b is a liquid (or mixed phase) output. In some embodiments, gas/liquid separator 36 is a condenser.

The system also includes a mixture expansion device 40 and a rectification column 38 . The mixture expansion device 40 is connected to receive the gas/vapour stream from the first output 36a of the gas/liquid separator 36, while the second output 36b of the gas/liquid separator 36 is connected to deliver the liquid (or mixed phase ).

The mixture expansion device 40 has separate first and second outputs 40a and 40b. The first output 40a is connected to rectification column 38 to deliver a first stream comprising mainly heavy components. The second output 40b is connected back as input to the first heat exchanger 32 to cool the gas mixture entering the first mixer 30 .

Rectification column 38 has separate first and second outputs 38a and 38b. The first output 38a is connected back to the second input 30b of the mixer 30 . The system 200 also includes a compressor 42 and a second chiller 44 connected in series between the first output 38a of the rectification column and the second input 30b of the mixer 30 .

Before describing the operation of the system 200 , further details of the mixture expansion device 40 are also given with reference to FIG. 2 . The mixture expansion device 40 has a tubular body with an input and an output generally indicated by A and B, respectively. The mixture expansion device 40 comprises a swirling device 41 near the input end and a converging-diverging nozzle section 43 following the swirling device 41 . In some embodiments, the swirling device 41 includes, without limitation, at least one vane. The converging-diverging spray section 43 opens into a conical section 45 leading to the outlet B. A flow splitter 47 is provided at output B within the tapered section 45 to facilitate splitting of the output flow to the respective first and second outputs 40a and 40b.

The mixture expansion device 40 can be made with a stream swirling device located at the inlet of the nozzle channel as shown in FIG. devices (such as discussed in prior art documents EP0496128 and WO99/01194).

Referring to Figures 1 and 2, the operation of the system 200 is as follows: A feed mixture 201 of natural gas (or other gas mixture) enters the system via a mixer 30 where it is mixed The return stream is mixed. The mixture of input natural gas and return gas is further cooled in the first heat exchanger 32 . According to a broad aspect of the invention, the first heat exchanger 32 facilitates the recycling of thermal energy, or conversely, in this particular case, the recycled energy is used to cool the various streams in the system. That is, the first heat exchanger 32 cools the feed natural gas mixture by transferring heat from the natural gas mixture to the return stream from the second output 40b of the mixture expansion device 40, thereby reducing the temperature of the natural gas mixture.

The natural gas mixture is further cooled in the first chiller 34 before entering the gas/liquid separator 36 . Within gas/liquid separator 36, the natural gas mixture is split into a gas/vapour stream and a liquid (or mixed phase) stream. The gas/vapor stream exits the gas/liquid separator 36 via the first output 36a and is fed directly to the mixture expansion device 40 . The liquid stream flows from the gas/liquid separator 36 to the rectification column 38 via a second output 36b.

Rectification column 38 outputs products in the gaseous phase via a first output 38a and products in the liquid phase via a second output 38b. The gas phase product is compressed in the compressor 42 and cooled in the second freezer 44 before being mixed with the feed mixture 201 as described above.

Referring specifically to Figure 2, within the mixture expansion device 40, the feed gas/vapour stream is divided into a first stream and a second stream. The natural gas mixture feed mixture expansion device 40 , swirled by swirling device 41 , and expanded through convergent-divergent nozzle section 43 . As the swirling gas mixture expands, the heavier components of the mixture drift away from the central axis, while the lighter components remain near the central axis. In this regard, the gas mixture stream is divided into at least a first and a second stream, so that the first stream mainly comprises heavier components and the second stream mainly comprises lighter components. The first stream exits the mixture expansion device 40 through the first output 40a. The second stream exits the mixture expansion device 40 through the second output 40b.

More specifically, in some embodiments, during the expansion process, the temperature of the gas/vapor stream is reduced sufficiently to induce partial condensation of the mixture, thereby forming a condensate. The condensate drops in the centrifugal force field and moves towards the wall of the mixture expansion device 40 where it collects into a two-phase flow. When the gas mixture is natural gas, the first stream contains components heavier than methane and the second stream contains substantially more methane gas.

In addition, due to the expansion of the mixture during the swirling movement in the mixture expansion device 40, the static pressure of the mixture is lower than the output pressure of the mixture expansion device 40, and the separation of the mixture in the nozzle is at a temperature lower than that of the mixture passing through the output. happened next. In some embodiments, greater separation of the mixture is provided as the gas phase product from rectification column 38 is returned to input mixture 201 prior to further processing of the mixture in system 200 .

After the streams are separated in the mixture expansion device, at least one of the streams is compressed by passing through a diffuser. Figure 2 shows an example when the mixture stream is split into two streams at the outlet of the nozzle channel in the mixture expansion device and then each stream is compressed in the diffuser. This makes it possible to reduce pressure losses across the expansion device.

The mixture or a portion thereof may be mixed in an ejector with the gas phase product from the rectification column before expansion. An example of implementation is shown in FIG. 1 , where an injector is used as mixer 30 .

In a next embodiment of the process of the present invention for the cryogenic separation of hydrocarbon gas mixtures, it comprises cooling the mixture, expanding the mixture or a part thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a part thereof in a rectification column To obtain liquid and gaseous phase products, according to the invention, the expansion process of the mixture is realized by passing the mixture through the nozzle channel, thereby swirling the mixture stream in the nozzle channel and/or at the nozzle channel inlet, and at the nozzle channel The outlet of the channel or a part thereof divides the mixture stream into at least two streams, one stream enriched in components heavier than methane and the other deficient in these components, and the enriched stream partially or completely It is passed to a rectification column, and the gas phase product from the rectification column is partly or completely mixed with the starvation stream. FIG. 3 shows a schematic diagram 300 of a cryogenic gas mixture separation system according to a second embodiment of the present invention, hereinafter referred to as system 300 for brevity. The system 300 shown in FIG. 3 is similar to the system 200 shown in FIG. 1 , and thus elements common to both share common reference numerals. In addition, for the sake of brevity, the part described for FIG. 1 is not repeated for FIG. 3 . Likewise, those skilled in the art will appreciate that system 300 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 300; however, what is shown is only necessary to describe aspects of the present embodiment A system 300 of those elements.

The differences between systems 200 and 300 are as follows: System 300 does not include first mixer 30 , first freezer 34 , second freezer 44 and first compressor 42 . System 300 includes a second mixer 48 and a first (throttle) valve 50 . The first valve 50 is connected between the second output 36b of the gas/liquid separator 36 and the rectification column 38 . Second mixer 48 includes respective separate first and second inputs connected to receive and mix gas/vapor outputs from mixture expansion device 40 and rectification column 38 . The second mixer 48 also includes an output connected to deliver the gas mixture to the first heat exchanger 32 .

In operation, feed mixture 301 is cooled in first heat exchanger 32 before entering separator 36 directly. The liquid stream from separator 36 is then passed through throttling valve 50 to rectification column 38 . The gas phase product from rectification column 38 is mixed with the second stream from mixture expansion device 40 (comprising mainly the lighter components of the separation process) in second mixer 48 to produce a mixed return stream. The combined return stream is then passed through a first heat exchanger 32 , where heat is transferred from the feed mixture 301 to the return stream, thereby cooling the feed mixture 301 without adding energy to the system 300 .

This approach can reduce the loss of mixture pressure required in cryogenic separation facilities.

In another embodiment of the method of the present invention for the cryogenic separation of a hydrocarbon gas mixture, it comprises cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column To obtain liquid and gas phase products, according to the invention, the mixture expansion process is realized by passing the mixture through the nozzle channel, thereby swirling the mixture stream in the nozzle channel and/or at the nozzle channel inlet, in the nozzle channel or Part of its outlet splits the mixed stream into at least two streams, one stream enriched in components heavier than methane and the other deficient in these components, allowing the enriched stream to pass through partially or completely To the mixture before expansion, and to partly or completely mix the gas phase product from the rectification column with the spent stream. Referring to FIG. 4 , there is shown a schematic diagram 400 of a cryogenic gas mixture separation system according to a third embodiment of the present invention, hereinafter referred to as system 400 for brevity. The system 400 shown in FIG. 4 is similar to the respective systems shown in FIGS. 1 and 3, and each common element shares a common reference numeral. In addition, for the sake of brevity, the part described for FIGS. 1 and 3 is not repeated for FIG. 4 . Those skilled in the art will appreciate that system 400 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 400; however, only those shown are representative of those necessary to describe aspects of the present embodiment System 400 of elements.

The specific arrangement of the system 400 is shown as follows: The system 400 includes the first mixer 30 as shown in FIG. 1 . System 400 also includes a second freezer 44 and a first compressor 42 . However, the first compressor 42 and the second refrigerator 44 are connected between the first heat exchanger 32 and the second output 30b (ie return input) of the first mixer 30 . In addition, the first output 40a of the mixture expansion device 40 is connected to the first heat exchanger 32 instead of being connected to the rectification column 38 as shown in FIG. 1 .

In operation, feed mixture 401 is mixed in first mixer 30 with a first stream, ie a stream comprising primarily the heavier components of the mixture separated in mixture expansion device 40 . That is, the first stream from the first output 40a of the mixture expansion device 40 is mixed with the feed mixture 401 . The output mixture from the first mixer 30 is then passed through a first heat exchanger 32 to further adjust the temperature of the feed gas mixture. The first heat exchanger 32 is connected to receive the first output 40a of the mixture expansion device 40 as a conditioned inflow. By using feedback, the energy of the system is conserved again and the efficiency can be improved.

In some embodiments, the gas phase product output from rectification column 38 is mixed in second mixer 48 with the second stream output from second output 40b of mixture expansion device 40, and the combined mixture is not transferred from system 400 output.

In one embodiment of the method of the present invention for the cryogenic separation of a hydrocarbon gas mixture, it comprises cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column To obtain liquid and gas phase products, according to the invention, the mixture expansion process is realized by passing the mixture through the nozzle channel, thereby swirling the mixture stream in the nozzle channel and/or at the nozzle channel inlet, in the nozzle channel or Part of its outlet splits the mixture stream into at least two streams, one stream enriched in components heavier than methane and the other depleted of these components, and the enriched stream combined with the The gas phase product in the column is partially or completely passed to the mixture before expansion. Referring to FIG. 5 , there is shown a schematic diagram 500 of a cryogenic gas mixture separation system according to a fourth embodiment of the present invention, hereinafter referred to as system 500 for brevity. The system 500 shown in FIG. 5 is similar to the respective systems shown in FIGS. 1 and 3-4, and each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-4 are not repeated for FIG. 5 . Those skilled in the art will understand that system 500 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 500; however only those necessary to describe aspects of the embodiment are shown System 500 of elements.

A specific arrangement for the system 500 is shown as follows: The system 500 includes a second heat exchanger 52 . The second mixer 48 and the second heat exchanger 52 are connected between the first output 36 a of the gas/liquid separator 36 and the input of the mixture expansion device 40 . As described with reference to FIG. 4 , a second heat exchanger 52 is also connected to receive the first stream from the first output 40 a of the mixture expansion device 40 before passing the first stream through the first heat exchanger 32 .

In operation, the vapor stream from separator 36 is mixed with the vapor phase output of rectification column 38 in second mixer 48 . The output of the second mixer 48 is cooled in a second heat exchanger 52 before passing through the mixture expansion device 40 . First, the first stream from the mixture expansion device 40 (from the first output 40a) is sent through the second heat exchanger 52 to cool the output of the second mixer 48, and then sent through the first heat exchanger 32 to further The output of the first mixer 30 is cooled. The same first stream is then compressed in the compressor 42 , after which it is cooled in the second freezer 44 before being mixed with the feed gas mixture 501 . The second stream may be output directly from system 500 (second output 40b from mixture expansion device 40). By using feedback, the energy of the system is conserved again and the efficiency can be improved.

In some embodiments, the system 500 facilitates advanced purification of the second stream from the mixture expansion device 40 (ie, the stream comprising primarily the lighter components of the gas mixture). That is, when natural gas processing is considered, because the first stream is mixed with the feed stream 501, the second stream may be significantly depleted of vapor components heavier than methane.

Before and/or after the expansion process, the liquid phase can be separated from the mixture or a part thereof passing through the throttling valve, and the resulting product is passed to a rectification column. Referring to FIG. 6 , there is shown a schematic diagram 600 of a cryogenic gas mixture separation system according to a fifth embodiment of the present invention, hereinafter referred to as system 600 for brevity, as an example. The system 600 shown in FIG. 6 is similar to the respective systems shown in FIGS. 1 and 3-5, and each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-5 are not repeated for FIG. 6 . Those skilled in the art will understand that system 600 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 600; however only those elements necessary to describe aspects of the present embodiment are shown The system 600.

A specific arrangement for the system 600 is shown as follows: The system 600 includes a second gas/liquid separator 60 . Second gas/liquid separator 60 includes separate first and second outputs 60a and 60b connected to second mixer 48 and rectification column 38, respectively. System 600 also includes a second (throttle) valve 66 between second output 60b and rectification column 38 input. A first output 40 a connected to the mixture expansion device 40 conveys the first stream from the mixture expansion device 40 to the second gas/liquid separator 60 .

In operation, because there are two gas/liquid separators 36 and 60, there are two liquid separations: before and after expanding the various forms of the mixture in the mixture expansion device 40. More specifically, the first stream from mixture expansion device 40 is sent to second separator 60 which provides a second vapor stream and a second liquid stream. The second liquid stream passes through the second throttle valve 66 and enters the rectification column 38 . The second vapor stream is mixed with the second stream from the mixture expansion device 40 in the second mixer 48 . The mixture 48 produced in the second mixer 48 is then passed through the first heat exchanger 32 as described above.

In the processes of all described embodiments, it is possible to additionally cool the gas phase products from the rectification column. Referring to FIG. 7 , there is shown a schematic diagram 700 of a cryogenic gas mixture separation system according to a sixth embodiment of the present invention, hereinafter referred to as system 700 for brevity, as an example. The system 700 shown in FIG. 7 is similar to the respective systems shown in FIGS. 1 and 3-6, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-6 are not repeated for FIG. 7 . Those skilled in the art will understand that system 700 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 700; however, only those elements necessary to describe aspects of the present embodiment are shown System 700.

A specific arrangement for the system 700 is shown as follows: A second heat exchanger 52 is connected between the first throttle valve 50 and the input of the rectification column 38 . The second refrigerator 44 is connected between the rectification column 38 and the second heat exchanger 52 . More specifically, a second chiller 44 is connected to receive and cool the vapor phase product from the first output 36a of the rectification column 38 . The second heat exchanger 52 is also connected to the first mixer 30 to provide the cooled gas phase product from the rectification column 38 as a return input to the first mixer 30 .

In operation, the feed mixture 701 is mixed with the gas phase products of the rectification column 38 as shown in FIG. . Next, second heat exchanger 52 heats the second stream from gas/liquid separator 36 before passing the second stream into rectification column 38 . This arrangement helps to provide a more reasonable mass and entropy flow distribution during cryogenic separation.

In some embodiments, at least part of the gas phase product from the rectification column is supplied to the mixture before expansion together with a part of the product obtained by passing the liquid separated from the mixture through a throttling valve. Referring to FIG. 8 , there is shown a schematic diagram 800 of a cryogenic gas mixture separation system according to a seventh embodiment of the present invention, hereinafter referred to as system 800 for brevity, as an example. The system 800 shown in Figure 8 is similar to the respective systems shown in Figures 1 and 3-7, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-7 are not repeated for FIG. 8 . Those skilled in the art will appreciate that system 800 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 800; however, only those elements necessary to describe aspects of the embodiment are shown System 800.

A specific arrangement for the system 800 is shown as follows: The first two expansions in the mixture expansion device 40 promote liquid separation by condensation. For this purpose, a second gas/liquid separator 60 is connected to receive a mixture of the liquid (or two-phase output) from the first gas/liquid separator 36 and the gas phase product from the rectification column 38 . In addition, the gas phase product from rectification column 38 is first connected through second heat exchanger 52 which also receives the liquid phase (or two phase) output of second separator 60, so that thermal energy can be transferred between the two, thus cooling One and heats the other, thus recirculating energy within the system 800 .

The feed mixture 801 is cooled in the first heat exchanger 32 and further cooled in the first freezer 34 before entering the first gas/liquid separator 36 . The liquid stream from separator 36 is passed through throttling valve 50 and mixed with the vapor phase products of rectification column 38 before entering second gas/liquid separator 60 . The second gas/liquid separator 60 also provides a second liquid stream which passes through the second heat exchanger 52, thereby cooling the gas phase products and heating the second liquid stream. After passing through the second heat exchanger 52 , the second liquid stream enters the rectification column 38 . Elsewhere in the system, the gas/vapor streams from the first and second gas/liquid separators 36 and 60 are fed into the mixture expansion device 40 where they undergo the process described above with respect to FIGS. 1 and 2 to produce the first The first and second streams were previously combined in a second mixer 48 . This approach enables a more deeply purified gas stream by removing a greater proportion of components heavier than methane as it is processed.

In some embodiments, a portion of the liquid separated from the mixture is passed through a throttling valve and the resulting product is used to cool the other mixture by passing it through the heated channels of a heat exchanger that cools the mixture, and these products are then passed to Mixture before expansion. Referring to FIG. 9 , there is shown a schematic diagram 900 of a cryogenic gas mixture separation system according to an eighth embodiment of the present invention, hereinafter referred to as system 900 for brevity, as an example. The system 900 shown in Figure 9 is similar to the respective systems shown in Figures 1 and 3-8, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-8 are not repeated for FIG. 9 . Those skilled in the art will understand that system 900 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 900; however, only those elements necessary to describe aspects of the embodiment are shown System 900.

The specific arrangement for the system 900 is shown as follows: the first freezer 34 precedes the first heat exchanger 32 . A third heat exchanger 62 is connected in series between the first heat exchanger 32 and the first gas/liquid separator 36 . A third heat exchanger 62 is also connected to receive part of the liquid (or two-phase) flow from the first gas/liquid separator 36 . To this end, a second throttle valve 66 is connected between the second output 36b and the third heat exchanger 62 to prevent reverse flow and maintain forward pressure through the third heat exchanger 62 . Additionally, similar to the system 500 shown in FIG. 5 , the gas phase product from rectification column 38 is combined with the gas/vapour stream from first gas/liquid separator 36 in mixer 48 prior to expansion. To this end, similarly to FIG. 8 , a second heat exchanger 52 is connected between the first output 38 a of the rectification column 38 and the second mixer 48 . The second heat exchanger 52 also receives the gas/vapor flow from the first gas/liquid separator 36 and connects the first throttle valve 50 therebetween.

In operation, a portion of the liquid stream from the first gas/liquid separator 36 is used to cool the feed mixture 901 . Feed mixture 901 is cooled by first freezer 34 and then mixed with a portion of the liquid stream from first gas/liquid separator 36, as described in more detail below. The resulting mixture is further cooled in the first heat exchanger 32 and in the third heat exchanger 62 before entering the first gas/liquid separator 36 . It should now be understood that the first gas/liquid separator 36 produces a gas/vapour stream and a liquid (or two-phase) stream. The gas/vapor stream is mixed with the gas phase product from rectification column 38 in second mixer 48, and the resulting gas/vapour mixture is expanded and split into first and second streams as described above for Figures 1 and 2 . The first stream enters rectification column 38 and the second stream returns to first heat exchanger 32 . Also, with respect to the systems described above, the heat exchanger facilitates the recirculation of energy in the system 900, thereby increasing the efficiency of the system 900.

In some embodiments, a turbo expander may be used either before or after expansion of the mixture. Referring to FIG. 10 , it shows a schematic diagram 1000 of a cryogenic gas mixture separation system according to a ninth embodiment of the present invention as an example, hereinafter referred to as system 1000 for brevity. The system 1000 shown in Figure 10 is similar to the respective systems shown in Figures 1 and 3-9, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-9 are not repeated for FIG. 10 . Those skilled in the art will appreciate that system 1000 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1000; however, only those elements necessary to describe aspects of the present embodiment are shown System 1000.

A specific arrangement for the system 1000 is shown as follows: The system 1000 includes a turbine 70 connected between the second output 40b of the mixture expansion device 40 and the first heat exchanger 32 . The system 1000 also includes a second compressor 64 connected in series between the first compressor 42 and the second output 36b of the first mixer 30 .

In operation, the second stream connected to the second output 40b of the mixture expansion device 40 passes through the turbine 70 and then through the first heat exchanger 32 . In some embodiments, a turbine device for mixture expansion may be used to provide additional expansion either before or after the mixture passes through the mixture expansion device 40 . Additionally, the feed mixture 1001 is mixed with a return gas/vapour stream comprising a portion of the liquid stream from the first gas/liquid separator 36 and a portion of the gas/vapor stream from the second gas/liquid separator 60 . The resulting mixture is then cooled in a first heat exchanger 32 before entering a first gas/liquid separator 36 . The liquid flow of the first gas/liquid separator 36 is divided into a first part and a second part. The first portion passes throttling valve 50 and enters rectification column 58 . A second portion of the first liquid stream passes through a second throttle valve 66 before being mixed with the gas/vapour stream of the second gas/liquid separator 60 . In contrast, the gas/vapour stream from the first gas/liquid separator 36 passes through the second heat exchanger 52 and is cooled therein before entering the second mixer 48 . The second mixer also receives gas phase products from rectification column 38 . The output of the second mixer 48 is then connected to the mixture expansion device 40 as described above. The first stream from the mixture expansion device 40 is passed into a second gas/liquid separator 60 . Second separator 60 also passes the liquid stream produced therefrom directly to rectification column 38 .

By using the turbine 70 described with the second stream from the mixture expansion device 40, the turbine blades (not shown) are lengthened because the amount of condensate (droplets) flowing on the blades is reduced, resulting in less wear ) service life.

In some embodiments, the compressor may be used for additional mixture compression in the event of insufficient pressure in the mixture to provide efficient operation for the turboexpander. Referring to FIG. 11 , it shows a schematic diagram 1100 of a cryogenic gas mixture separation system according to a tenth embodiment of the present invention as an example, hereinafter referred to as system 1100 for brevity. The system 1100 shown in Figure 11 is similar to the respective systems shown in Figures 1 and 3-10, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-10 are not repeated for FIG. 11 . Those skilled in the art will understand that system 1100 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1100; however, only those elements necessary to describe aspects of the present embodiment are shown System 1100.

The specific arrangement for the system 1100 is shown as follows: Again, the first input 30a of the first mixer 30 is used as the input of the system 1100 as well as the input of the first mixer 30 . A first compressor 42 is connected in series between the first mixer 30 and the first refrigerator 34 , which is in turn connected in series with the first heat exchanger 32 . The first and second outputs of the first heat exchanger 32 are connected to the first gas/liquid separator 36 and the second compressor 64, respectively. The second output 36b of the first gas/liquid separator 36 is connected to the parallel combination of the first and second throttle valves 50 and 66, which in turn are connected to the rectification column 38 and the second heat exchanger 52, respectively. That is, the liquid (two-phase) stream from the first gas/liquid separator is split between the second heat exchanger 52 and the rectification column. A second heat exchanger 52 is also connected to receive the gas/vapour stream output of the first gas/liquid separator before the gas/vapour stream enters the mixture expansion device.

The system 1100 is particularly useful when in operation the feed mixture 1101 enters at a lower differential pressure. More specifically, the feed mixture 1101 is mixed with the second stream separated in the mixture expansion device. The resulting combined mixture is then compressed in the first compressor 42 before being cooled in the first freezer 34 and first heat exchanger 32 .

The liquid flow from the first gas/liquid separator 36 is divided into a first portion entering the rectification column 38 through the first throttle valve 50 and a second portion entering the second heat exchanger 52 through the second throttle valve 66 . After passing through the second heat exchanger 52 , the second portion enters the second mixer 48 where it is mixed with the vapor phase product of the rectification column 38 . The mixture is then fed back to the first mixer 30 for mixing with the feed mixture 1101, as described above. The gas/vapor stream 36 from the first separator 36 is sent to a mixture expansion device 40 and undergoes the process described above for FIGS. 1 and 2 .

In another very particular embodiment, after the initial mixture has been mixed with the product returning to the initial mixture, said mixture is additionally compressed in a compressor. Referring to FIG. 12 , there is shown a schematic diagram 1200 of a cryogenic gas mixture separation system according to an eleventh embodiment of the present invention, hereinafter referred to as system 1200 for brevity, as an example. The system 1200 shown in Figure 12 is similar to the respective systems shown in Figures 1 and 3-11, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-11 are not repeated for FIG. 12 . Those skilled in the art will understand that system 1200 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1200; however, only those elements necessary to describe aspects of the present embodiment are shown System 1200.

The specific arrangement for the system 1200 is shown as follows: The gas/vapour stream from the first gas/liquid separator 36 is split into two streams. The first stream is connected to a mixture expansion device 40 . The second stream is connected to a turbine 70 arranged parallel to the mixture expansion device 40 . The first output 40 a of the mixture expansion device 40 and the output of the turbine 70 meet at a second mixer 48 which is then connected to the rectification column 38 . The second output 40b of the mixture expansion device 40 and the first output 38a of the rectification column meet at a third mixer 68 which is then connected in series with the second heat exchanger 52 and second compressor 64 . System 1200 is useful in situations where it is desired to provide increased pressure within the system to improve separation of mixtures.

In operation, after the feed mixture 1201 is mixed with a portion of the liquid stream from the first gas/liquid separator 36, the resulting mixture is compressed in the compressor 42 and transferred between the first freezer 34 and the first heat exchanger 32 cool down. Another portion of the liquid stream from first gas/liquid separator 36 is passed through throttling valve 50 and into rectification column 38 . The gas/vapor flow of the first gas/liquid separator 36 is also divided into two parts. The first part is passed into the turbine 70 and the second part is passed into the mixture expansion device 40 . The first stream from mixture expansion device 40 is mixed with the output of turbine 70 and sent to rectification column 38 . The second stream is mixed with the gas phase products from rectification column 38 and passes through second heat exchanger 52 and compressor 64 before exiting the system.

In a very particular embodiment, the gaseous product from the rectification column is cooled and expanded, and the fraction of the product enriched in components heavier than methane is separated and passed partly or completely to the rectification column. Referring to FIG. 13 , there is shown a schematic diagram 1300 of a cryogenic gas mixture separation system according to a twelfth embodiment of the present invention, hereinafter referred to as system 1300 for brevity, as an example. The system 1300 shown in Figure 13 is similar to the respective systems shown in Figures 1 and 3-12, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-12 are not repeated for FIG. 13 . Those skilled in the art will understand that system 1300 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1300; however, only those elements necessary to describe aspects of the present embodiment are shown System 1300.

A specific arrangement for the system 1300 is shown as follows: The system 1300 includes a second mixture expansion device 80 similar in design and function to the mixture expansion device 40 described above with respect to FIG. 2 . Like the first mixture expansion device 40, the mixture expansion device 80 has separate first and second outputs 80a and 80b. The connected first output 80a conveys the first stream of heavier components to the second gas/liquid separator 60 and the connected second output 40b sends the second stream of lighter components to the second gas/liquid separator. 60 gas/vapour streams combined. The system 1300 also includes a pump 72 and a third throttle valve 74 connected in series between the liquid (or two-phase) stream of the second gas/liquid separator 60 (i.e., the second output 60b) and the third heat exchanger 62, The third heat exchanger is then connected to the rectification column 38 . The gas phase product from rectification column 38 is also connected via a third heat exchanger 62 .

In operation, the gas phase product from rectification column 38 is cooled, expanded (in second mixture expansion device 80) and separated, and the resulting second stream from second mixture expansion device 80 is partially or fully returned to rectification Distillation tower 38.

Thus, in some embodiments, the gas phase product from the rectification column is additionally compressed in a compressor. Referring to FIG. 14 , there is shown a schematic diagram 1400 of a cryogenic gas mixture separation system according to a thirteenth embodiment of the present invention, hereinafter referred to as system 1400 for brevity, as an example. The system 1400 shown in Figure 14 is similar to the respective systems shown in Figures 1 and 3-13, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-13 are not repeated for FIG. 14 . Those skilled in the art will appreciate that system 1400 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1400; however, only those elements necessary to describe aspects of the present embodiment are shown System 1400.

A specific arrangement for the system 1400 is shown as follows: The system 1400 includes a cooling and compression circuit connected between the first output 38a of the rectification column 38 and the input of the second gas/liquid separator 60, including a third heat exchanger 76 connected in series , the second compressor 64 and the second refrigerator 44 . The output of the second chiller 44 is then connected in a return circuit through a third heat exchanger 76 . The first output 60a (ie the gas/vapor output) of the second gas/liquid separator 60 is connected to a second mixture expansion device 80 . A first output 80a of the mixture expansion device 80 (comprising the heavier separated components from the expansion and separation process) is connected to the rectification column 38 and a second output 80b is combined with the second output 40b of the mixture expansion device 40 .

In operation, the vapor phase product from rectification column 38 is frozen and compressed in the cooling and compression circuit described above. Specifically, the vapor phase product from rectification column 38 is cooled in heat exchanger 76, compressed in compressor 64, cooled in freezer 44, and further processed in a second vapor/liquid separator 60 before entering second gas/liquid separator 60 Cooled in heat exchanger 62. The liquid stream from the second gas/liquid separator 60 also passes through a second heat exchanger 62 before entering the rectification column 38 . The remaining operation of system 1400 is similar to system 1300 shown in FIG. 13 .

In another very specific embodiment, the gaseous product from the rectification column 38 is expanded to obtain a product enriched in components heavier than methane; the latter is passed partly or completely to the rectification column, or prior to its expansion Returned to the gas phase product stream. Referring to FIG. 15 , there is shown a schematic diagram 1500 of a cryogenic gas mixture separation system according to a fourteenth embodiment of the present invention, hereinafter referred to as system 1500 for brevity, as an example. The system 1500 shown in Figure 15 is similar to the respective systems shown in Figures 1 and 3-14, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-14 are not repeated for FIG. 15 . Those skilled in the art will understand that system 1500 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1500; however, only those elements necessary to describe aspects of the embodiment are shown System 1500.

The specific arrangement for the system 1500 is shown as follows: In the system 1500 the first output 38a of the rectification column 38 is connected to the second mixture expansion device 80 via the second chiller 44 . The first output 80a of the mixture expansion device 80 is connected to the second gas/liquid separator 60 . Next, as also shown in FIG. 14 , the liquid stream (or two-phase) output of separator 60 is passed into rectification column 38 .

In operation, the vapor phase product from rectification column 38 is expanded within second mixture expansion device 80 to separate heavy and light components from each other as described above with respect to FIG. 2 . The first output 80a (comprising heavier components) from the second mixture expansion device 80 flows into the second gas/liquid separator 60 . The liquid (or two-phase) output is pumped into rectification column 38 through pump 72 and third throttle valve 74 . The second output 80b of the mixture expansion device 80 is mixed with the gas/vapor stream output from the second separator 60 and the second output 40b of the mixture expansion device 40 . The resulting mixture is returned to the first heat exchanger 32 to cool the feed mixture 1501 . The feed mixture 1501 which has been mixed with the return stream as previously described is also compressed before entering the first gas/liquid separator 36 . The rest of the operation is similar to the previously described system.

In another embodiment, the enriched stream obtained after expansion of the gas phase product from the rectification column is passed to the initial mixture before expansion. Referring to FIG. 16 , there is shown a schematic diagram 1600 of a cryogenic gas mixture separation system according to a fifteenth embodiment of the present invention, hereinafter referred to as system 1600 for brevity, as an example. The system 1600 shown in Figure 16 is similar to the respective systems shown in Figures 1 and 3-15, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-15 are not repeated for FIG. 16 . Those skilled in the art will understand that system 1600 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1600; however, only those elements necessary to describe aspects of the embodiment are shown System 1600.

The specific arrangement for system 1600 is shown as follows: Unlike system 1500 , system 1600 includes only first gas/liquid separator 36 . A third heat exchanger 62 is connected in series between the first output 38a of the rectification column 38 and the input of the second mixture expansion device 80 . The first output 80a of the mixture expansion device 80 is fed back and connected through the third heat exchanger 62 by means of the third throttle valve 74, and connected through the second heat exchanger 52, which in turn is connected back to the first mixing device 30.

In operation, the first stream separated in the second mixture expansion device 80 passes through the third and second heat exchangers 62 and 52, respectively, before being combined with the feed mixture 1601. The liquid (or two-phase) output stream from the first gas/liquid separator 36 is also mixed with the first stream separated in the second mixture expansion device 80 before the second heat exchanger 52 . The second throttle valve 66 reduces the pressure of the stream output to the first gas/liquid separator 36 . The rest of the operation is similar to the system discussed with reference to FIG. 15 .

In some embodiments, the mixture, or a portion thereof, is passed through a turbine of a turboexpander before or after expansion. Referring to FIG. 17 , there is shown a schematic diagram 1700 of a cryogenic gas mixture separation system according to a sixteenth embodiment of the present invention, hereinafter referred to as system 1700 for brevity, as an example. The system 1700 shown in Figure 17 is similar to the respective systems shown in Figures 1 and 3-16, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-16 are not repeated for FIG. 17 . Those skilled in the art will understand that system 1700 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1700; however, only those elements necessary to describe aspects of the present embodiment are shown System 1700.

A specific arrangement for system 1700 is shown as follows: System 1700 includes four gas/liquid separators, first and second gas/liquid separators 36 and 60 and additional third and fourth gas/liquid separators 82 and 84 . The first and second gas/liquid separators 36 and 60 are connected such that the gas/vapor output of the first gas/liquid separator 36 is connected into the second gas/liquid separator 60 . As shown in FIG. 17, a turbine 70 and a second mixer 48 are connected in between. The liquid outputs of the first and second gas/liquid separators 36 and 60 are combined and connected to a third separator 82 . The liquid output of the third separator 82 is connected to the fourth separator 84 by means of the second heat exchanger 52 . The liquid output of the fourth gas/liquid separator 84 is connected to the rectification column 38 , while the gas/vapour output is connected to the second gas/liquid separator 60 through the second mixer 48 . The gas/vapor output stream of the second gas/liquid separator 60 is connected into the mixture expansion device 40 . The compressor stage of the mixture expansion turbine device can be used as the compressor 42, and this solution can improve the power consumption in the cryogenic separation process.

In operation, feed mixture 1701 is cooled by sequentially combining first and second heat exchangers 32 and 52 before entering first gas/liquid separator 36 . The liquid streams from the first and second gas/liquid separators 36 , 60 are combined and passed to the third gas/liquid separator 82 together with the first stream produced by the mixture expansion device 40 . The third gas/liquid separator 82 produces a liquid stream that is used as a coolant in the second heat exchanger 52 before further processing in the fourth gas/liquid separator 84 . The liquid stream produced by the fourth gas/liquid separator 84 is then sent to the rectification column 38 . The gas/vapour streams from the third and fourth gas/liquid separators 82 and 84 are combined and fed back to the second gas/liquid separator along with the gas/vapor stream from the first gas/liquid separator 36 60.

In other embodiments, the liquid phase is separated from the mixture, a portion of the liquid phase is passed through a throttling valve; the resulting product is used to cool the mixture and passed to the mixture prior to expansion. Referring to FIG. 18 , there is shown a schematic diagram 1800 of a cryogenic gas mixture separation system according to a seventeenth embodiment of the present invention, hereinafter referred to as system 1800 for brevity, as an example. The system 1800 shown in Figure 18 is similar to the respective systems shown in Figures 1 and 3-17, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-17 are not repeated for FIG. 18 . Those skilled in the art will appreciate that system 1800 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1800; however, only those elements necessary to describe aspects of the embodiment are shown System 1800.

A specific arrangement for the system 1800 is shown as follows: The liquid stream output 36b of the first gas/liquid separator 36 is connected to the rectification column 38 and the third heat exchanger 62 . A third heat exchanger 62 is connected in series between the first heat exchanger 32 and the first gas/liquid separator 36 . Additionally, the third heat exchanger 62 connects the liquid stream output 36b back to the first mixer 30 via the first compressor 42 and the second chiller 44 .

In operation, the feed mixture 1801 is cooled using a partial liquid stream from the first gas/liquid separator 36, as shown in the example in FIG. The feed mixture 1801 is cooled by the first freezer 34 and then mixed with part of the liquid stream from the first gas/liquid separator 36 . However, this portion of the liquid stream is first used as coolant in the third heat exchanger 62 and then compressed and cooled before being added to the feed mixture 1801. The remainder of the system operates as described for FIG. 3 .

According to some embodiments, the mixture is split into at least two streams prior to expansion, one is passed through the turbine of the turboexpander and directed to the rectification column, and the other stream is expanded by passing the swirling mixture stream through the nozzle channels ; the outlet mixture stream at the nozzle channel or a part thereof is divided into at least two streams, one stream enriched in components heavier than methane, and the other stream depleted of these components; the enriched material is then flow to the distillation column. Referring to FIG. 19 , there is shown a schematic diagram 1900 of a cryogenic gas mixture separation system according to an eighteenth embodiment of the present invention, hereinafter referred to as system 1900 for brevity, as an example. The system 1900 shown in Figure 19 is similar to the respective systems shown in Figures 1 and 3-18, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-18 are not repeated for FIG. 19 . Those skilled in the art will understand that system 1900 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 1900; however, only those elements necessary to describe aspects of the embodiment are shown System 1900.

A specific arrangement for the system 1900 is shown as follows: The gas/vapour stream from the first gas/liquid separator 36 is split into two streams. The first stream is connected to a mixture expansion device 40 . The second stream is connected to a turbine 70 arranged in parallel with the mixture expansion device 40 . The first output 40a of the mixture expansion device 40 and the output of the turbine 70 are connected into the rectification column 38 . The second output 40b of the mixture expansion device 40 and the first output 38a of the rectification column 38 meet at a second mixer 48 which is then connected in series with the first heat exchanger 32 . System 1900 is useful in situations where it is desired to provide increased pressure within the system to improve separation of mixtures.

In operation, feed mixture 1901 is cooled in first heat exchanger 32 and separated in first gas/liquid separator 36 . The liquid stream from separator 36 enters rectification column 18 through valve 50 . Prior to expansion, the gas/vapor stream produced by the first gas/liquid separator 36 is split into at least two streams, one of which is pumped through the turbine 70 of the turbine arrangement used for the expansion of the mixture, and is passed to the rectification column 38, While the other stream is expanded through the mixture expansion device 40 . The first stream from the mixture expansion device 40 is sent to the rectification column 38, while the second stream is mixed with the gas phase product from the rectification column 38, their mixture is sent through the first heat exchanger 32, and in the first Compressed in the compressor 42 and output. This method can be used to further purify the mixture and remove substantially heavier components from the mixture.

Accordingly, in some embodiments, the stream enriched during expansion is mixed in the ejector with the portion of the mixture that passes through the turbine of the turboexpander. Referring to FIG. 20 , there is shown a schematic diagram 2000 of a cryogenic gas mixture separation system according to a nineteenth embodiment of the present invention, hereinafter referred to as system 2000 for brevity, as an example. The system 2000 shown in Figure 20 is similar to the respective systems shown in Figures 1 and 3-19, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-19 are not repeated for FIG. 20 . Those skilled in the art will appreciate that system 2000 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 2000; however, only those elements necessary to describe aspects of the embodiment are shown System 2000.

The specific arrangement for system 2000 is shown as follows: System 2000 is almost identical to system 1900 except that compressor 42 is not included. In operation, both the system 2000 as well as the system 1900 can facilitate increased efficiency of the turbine 70 of the turbo device for mixture expansion, thereby providing deeper gas cooling in the turbine 70 and allowing greater compression ratios.

In other embodiments, the pre-expanded mixture stream is divided into at least three streams, one stream passes through a valve controlling the mass flow rate and either passes to the rectification column or is mixed with the gas phase product from the column. Referring to FIG. 21 , there is shown, as an example, a schematic diagram 2100 of a cryogenic gas mixture separation system according to a twentieth embodiment of the present invention, hereinafter referred to as system 2100 for brevity. The system 2100 shown in Figure 21 is similar to the respective systems shown in Figures 1 and 3-20, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-20 are not repeated for FIG. 21 . Those skilled in the art will appreciate that system 2100 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 2100; however, only those elements necessary to describe aspects of the present embodiment are shown System 2100.

A specific arrangement for the system 2100 is shown as follows: the first output 36a of the first gas/liquid separator 36 is split between the turbine 70 , the mixture expansion device 40 and the third mixer 68 . The third mixer 68 also receives the first stream from the mixture expansion device 40 and the gas phase products from the rectification column 38 .

In operation, the gas/vapour stream produced by the first separator 36 is divided into three portions which pass through the turbine 70, the mixture expansion device 40 and the third mixer 68, respectively. The remaining components operate as discussed for Figures 19 and 20. This method can stabilize the mass flow rate with the turbine 70 of the turbine arrangement for expansion of the mixture in case of variations in the feed mixture 2101 .

According to some embodiments, the liquid phase is separated from the mixture, a portion of the mixture is passed through a throttling valve, and a portion of the resulting product is used to cool the mixture and pass to the mixture before expansion. Referring to FIG. 22 , there is shown a schematic diagram 2200 of a cryogenic gas mixture separation system according to a twenty-first embodiment of the present invention, hereinafter referred to as system 2200 for brevity, as an example. The system 2200 shown in Figure 22 is similar to the respective systems shown in Figures 1 and 3-21, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-21 are not repeated for FIG. 22 . Those skilled in the art will understand that system 2200 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 2200; however, only those elements necessary to describe aspects of the present embodiment are shown System 2200.

The specific arrangement for the system 2200 is shown as follows: The second output (i.e. liquid output) of the first gas/liquid separator and the first output 40a of the mixture expansion device 40 are connected into a second mixer 48 which in turn is connected to the first heat The switch 32 is connected.

In operation, the feed mixture 2201 is cooled in the first heat exchanger 32 using the liquid output of the first gas/liquid separator 36 and the resulting mixture from the first stream of the mixture expansion device 40, and fed to the first mixer 30 in the feed mixture 2201. This approach may be effective where lighter components from feed mixture 2201 are included in the gas phase product produced by rectification column 38 . For example, when processing natural gas, the gas phase product produced by rectification column 38 may have very small amounts of components heavier than methane.

In another embodiment, the liquid phase is separated from the mixture passing through the throttling valve, and the resulting product is used to cool the mixture. Referring to FIG. 23 , there is shown a schematic diagram 2300 of a cryogenic gas mixture separation system according to a twenty-second embodiment of the present invention, hereinafter referred to as system 2300 for brevity, as an example. The system 2300 shown in Figure 23 is similar to the respective systems shown in Figures 1 and 3-22, and thus each common element shares a common reference numeral. In addition, for the sake of brevity, the parts described for FIGS. 1 and 3-22 are not repeated for FIG. 23 . Those skilled in the art will appreciate that system 2300 includes an appropriate combination of related structural components, mechanical systems, hardware, firmware, and software to support the function and operation of system 2300; however, only those elements necessary to describe aspects of the present embodiment are shown System 2300.

The specific arrangement for the system 2300 is shown as follows: the second output 36b of the first gas/liquid separator 36 is connected to a part of the first output 40a of the mixture expansion device 40 and connected to the second and third heat exchangers 52 and 62 . The first output 38a of the rectification column 38 is also connected to a corresponding output of the third heat exchanger 62 and then into the first compressor 42 . The first compressor 42 is then connected in series with the second freezer 44 to the first mixer 30 which also receives the feed mixture 2301 .

In operation, the output of the liquid stream from the first gas/liquid separator 36 is combined with the first stream produced by the mixture expansion device 40 . This mixture is used to cool the gas/vapour stream from the first gas/liquid separator 36 in the second heat exchanger 52, and in the third heat exchanger 62 before being combined with the feed mixture 2301 in the mixer 30. Cool the feed mixture 2301 in the middle. System 2300 is adapted to process a gas mixture having a target component concentration lower than that in the feed mixture.

What has been described is merely illustrative of the application of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teaching. It is therefore to be understood that within the scope of the following claims, the invention may be practiced otherwise than as specifically described herein.

Claims (64)

1. A process for the cryogenic separation of a hydrocarbon gas mixture comprising cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column to obtain a liquid phase and products in the gas phase, wherein the expansion process of the mixture is achieved by passing the mixture through a nozzle channel, thereby swirling the stream of the mixture in the nozzle channel and/or at the inlet of the nozzle channel, at the outlet of the nozzle channel or a part thereof splitting the mixture stream into at least two streams, one stream enriched in components heavier than methane and the other stream deficient in these components; part of the stream enriched in components heavier than methane or All are passed to the rectification column, and the gas phase product obtained in the rectification column is partially or completely passed to the mixture before expansion. 2. The method of claim 1, wherein after separating the mixture stream in the mixture expansion device, the mixture stream is compressed by passing at least one of the mixture streams through a diffuser. 3. The method of claim 1, wherein the mixture, or a portion thereof, is mixed in an eductor with a gaseous product from a rectification column prior to expansion. 4. The process of claim 1, wherein before and/or after expansion, the liquid phase is separated from the mixture passing through the throttle valve or a part thereof, and the product obtained after said throttle valve is partly or completely to the distillation column. 5. The method of claim 1, wherein the gas phase product from the rectification column is additionally cooled. 6. A process as claimed in claim 4, wherein at least part of the gas phase product from the rectification column is passed to the mixture before expansion together with a part of the product obtained after the throttle valve. 7. The method of claim 4, wherein at least part of the liquid phase separated from the mixture or a portion thereof is passed to a heat exchanger and then to the mixture before expansion. 8. The method of claim 6 or 7, wherein the mixture or a portion thereof is passed through the turbine of the turboexpander before or after expansion. 9. The method of claim 8, wherein the mixture is additionally compressed in a compressor prior to expansion. 10. The method of claim 1, wherein after the initial mixture is mixed with the gas phase product from the rectification column, the resulting mixture is additionally compressed in a compressor. 11. A process as claimed in claim 10, wherein the gas phase product from the rectification column is cooled and expanded, and the part of the product which is passed partially or completely to the rectification column enriched in components heavier than methane is separated. 12. The method of claim 11, wherein the gas phase product from the rectification column is additionally compressed in a compressor before cooling. 13. The method of claim 12, wherein the gaseous phase product from the rectification column is expanded to obtain a product enriched in components heavier than methane, the latter being partially or completely passed to the rectification column, or returned to the gas phase before expansion in the product stream. 14. Process according to claim 13, wherein the part of the product enriched in components heavier than methane obtained after expansion of the gas phase product is returned to the gas phase product stream before expansion. 15. The method of claim 5, wherein the mixture or a portion thereof is passed through a turbine of a turboexpander before or after expansion. 16. A process for the cryogenic separation of a hydrocarbon gas mixture comprising cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column to obtain a liquid phase and gaseous phase products, wherein the expansion process of the mixture is achieved by passing the mixture through a nozzle channel, thereby swirling the stream of the mixture in the nozzle channel and/or at the inlet of the nozzle channel, causing the mixture at the outlet of the nozzle channel or a part thereof Dividing a stream into at least two streams, one stream enriched in components heavier than methane and the other deficient in these components; partial or total depletion of the stream enriched in components heavier than methane It is passed to a rectification column and the gaseous product from the rectification column is mixed partly or completely with another stream which is deficient in these components. 17. The method of claim 16, wherein after separating the mixture stream, the mixture stream is compressed by passing at least one of them through a diffuser. 18. The method of claim 16, wherein before and/or after expansion, the liquid phase is separated from the mixture passing through the throttle valve or a part thereof, and the product obtained after said throttle valve is partly or completely to the distillation column. 19. The method of claim 16, wherein the gas phase product from the rectification column is additionally cooled. 20. A process as claimed in claim 18, wherein at least part of the gas phase product from the rectification column is passed to the pre-expansion mixture together with a part of the product obtained after the throttling valve. 21. The method of claim 18, wherein at least part of the liquid phase separated from the mixture or a portion thereof is passed to a heat exchanger and then to the mixture before expansion. 22. The method of claim 16, wherein during or after the expansion process, the liquid phase is separated from the mixture, part of the liquid phase is passed through a throttle valve, and part of the product obtained after the throttle valve is used for cooling the mixture or a part thereof, And pass this obtained partial product to the mixture before expansion. 23. The method of claim 16, wherein the hydrocarbon gas mixture stream is divided into at least two parts, a part of which is pumped through the turbine of the turboexpander and led to the rectification column, while the other part is swirled through the nozzle channel The stream is expanded to obtain a portion of the stream enriched in components heavier than methane, which is passed to a rectification column. 24. The method of claim 23, wherein the enriched stream obtained during the expansion process and the stream passing through the turbine of the turboexpander are mixed in an ejector. 25. The method of claim 23, wherein said hydrocarbon gas mixture stream is divided into at least three streams, one stream of which is led to a rectification column through a valve controlling the mass flow rate, or is mixed with the product in the gas phase from the rectification column mix. 26. The method of claim 16 or 22, wherein the mixture or a portion thereof is passed through the turbine of a turboexpander before or after expansion. 27. The method of claim 26, wherein the mixture is additionally compressed in a compressor prior to expansion. 28. Process according to one of claims 16, 22, 24, 25, wherein after the initial mixture has been mixed with the gas phase product from the rectification column, the resulting mixture is additionally compressed in a compressor. 29. A process as claimed in claim 28, wherein the gas phase product from the rectification column is cooled and expanded, and a portion of the product which is passed partially or entirely to the rectification column enriched in components heavier than methane is separated. 30. The method of claim 29, wherein the gas phase product from the rectification column is additionally compressed in a compressor prior to cooling. 31. The process of claim 30, wherein the gaseous phase product from the rectification column is expanded to obtain a product enriched in components heavier than methane, which is partially or completely passed to the rectification column, or returned to the gas phase before expansion in the product stream. 32. A process as claimed in claim 31, wherein the part of the product enriched in components heavier than methane obtained after expansion of the gas phase product is returned to the gas phase product stream before expansion. 33. The method of claim 19, wherein the mixture or a portion thereof is passed through a turbine of a turboexpander before or after expansion. 34. A process for the cryogenic separation of a hydrocarbon gas mixture comprising cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column to obtain a liquid phase and gaseous phase products, wherein the expansion process of the mixture is achieved by passing the mixture through a nozzle channel, thereby swirling the stream of the mixture in the nozzle channel and/or at the inlet of the nozzle channel, causing the mixture at the outlet of the nozzle channel or a part thereof Dividing a stream into at least two streams, one stream enriched in components heavier than methane and the other deficient in these components; partial or total depletion of the stream enriched in components heavier than methane The mixture before expansion is passed, and the gaseous phase product from the rectification column is partially or completely mixed with another stream which is deficient in these components. 35. The method of claim 34, wherein after separating the mixture stream, the mixture stream is compressed by passing at least one of the mixture streams through a diffuser. 36. The method of claim 34, wherein before or after expansion, the liquid phase is separated from the mixture or a part thereof passing through a throttle valve, and the product obtained after said throttle valve is partially or completely passed to Distillation tower. 37. The method of claim 34, wherein the vapor phase product from the rectification column is additionally cooled. 38. The method of claim 36, wherein at least part of the gas phase product from the rectification column is passed to the pre-expansion mixture together with a part of the product obtained after the throttling valve. 39. The method of claim 36, wherein at least part of the liquid phase separated from the mixture or a portion thereof is passed to a heat exchanger and then to the mixture prior to expansion. 40. The method of claim 34, wherein during or after the cooling process, the liquid phase is separated from the mixture passing through the throttle valve, part of the product obtained after the throttle valve is used for cooling the mixture, and the obtained part The product leads to the mixture before expansion. 41. The method of claim 34 or 40, wherein the mixture, or a portion thereof, is passed through a turbine of a turboexpander before or after expansion. 42. The method of claim 41, wherein the mixture is additionally compressed in a compressor prior to expansion. 43. The method according to claim 34 or 40, wherein after the initial mixture is mixed with the gas phase product from the rectification column, the resulting mixture is additionally compressed in a compressor. 44. The method of claim 43, wherein the gaseous phase product from the rectification column is cooled and expanded, and a portion of the product enriched in components heavier than methane passed to the rectification column partially or completely is separated. 45. The method of claim 43, wherein the gas phase product from the rectification column is additionally compressed in a compressor prior to cooling. 46. The process of claim 45, wherein the gas phase product from the rectification column is expanded to obtain a product enriched in components heavier than methane, the latter being partially or completely passed to the rectification column, or returned to the gas phase before expansion in the product stream. 47. A process according to claim 46, wherein the part of the product enriched in components heavier than methane obtained after expansion of the gas phase product is returned to the gas phase product stream before expansion. 48. The method of claim 37, wherein the mixture or a portion thereof is passed through a turbine of a turboexpander before or after expansion. 49. A process for the cryogenic separation of a hydrocarbon gas mixture comprising cooling the mixture, expanding the mixture or a portion thereof without performing mechanical work, partially condensing the mixture during its expansion, separating the mixture or a portion thereof in a rectification column to obtain a liquid phase and gaseous phase products, wherein the expansion process of the mixture is achieved by passing the mixture through a nozzle channel, thereby swirling the stream of the mixture in the nozzle channel and/or at the inlet of the nozzle channel, causing the mixture at the outlet of the nozzle channel or a part thereof splitting the stream into at least two streams, one enriched in components heavier than methane and the other deficient in these components; combining the stream enriched in components heavier than methane with the The gas phase product of the column is passed partly or completely to the mixture before expansion. 50. The method of claim 49, wherein after separating the mixture stream, the mixture stream is compressed by passing at least one of the mixture streams through a diffuser. 51. The method of claim 49, wherein the mixture, or a portion thereof, is mixed in an eductor with a gaseous product from a rectification column prior to expansion. 52. The method of claim 49, wherein before and/or after expansion, the liquid phase is separated from the mixture passing through the throttle valve or a part thereof, and the product obtained after said throttle valve is partly or completely to the distillation column. 53. The method of claim 49, wherein the vapor phase product from the rectification column is additionally cooled. 54. The method of claim 49, wherein at least part of the gas phase product from the rectification column is passed to the mixture before throttling together with a part of the product obtained after the throttling valve. 55. The method of claim 52, wherein at least part of the liquid phase separated from the mixture or a portion thereof is passed to a heat exchanger and then to the mixture prior to expansion. 56. The method of claim 49, wherein before or after expansion, the liquid phase is separated from the mixture, part of the liquid phase is passed through a throttle valve, and the product obtained after the throttle valve is used to cool the mixture or a part thereof . 57. The method of claim 49 or 56, wherein the mixture, or a portion thereof, is passed through the turbine of a turboexpander before or after expansion. 58. The method of claim 56, wherein the mixture is additionally compressed in a compressor prior to expansion. 59. A process according to claim 49 or 56, wherein after the initial mixture is mixed with the gas phase product from the rectification column, the resulting mixture is additionally compressed in a compressor. 60. The method of claim 59, wherein the gas phase product from the rectification column is cooled and expanded, and a portion of the product enriched in components heavier than methane that is passed to the rectification column partially or completely is separated. 61. The method of claim 60, wherein the gas phase product from the rectification column is additionally compressed in a compressor prior to cooling. 62. The method of claim 61, wherein the gaseous phase product from the rectification column is expanded to obtain a product enriched in components heavier than methane, and the product is partially or completely passed to the rectification column, or returned to the pre-expansion in the gas phase product stream. 63. The process of claim 62, wherein a part of the product enriched in components heavier than methane obtained after expansion of the gas phase product is returned to the gas phase product stream before expansion. 64. The method of claim 53, wherein the mixture, or a portion thereof, is passed through a turbine of a turboexpander before or after expansion.

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