Membrane method carbon capture skid-mounted device

Abstract

The invention belongs to the technical field of flue gas carbon capture devices, and particularly relates to a membrane method carbon capture skid-mounted device. The skid comprises a first skid and a second skid which are arranged on the bottom layer side by side, a third skid is arranged on the second skid in an overlapped mode, and the rectifying tower comprises a rectifying tower upper half section and a rectifying tower lower half section; a first-stage compressor, a second-stage compressor, a product gas compressor and a refrigerating unit compressor are mounted on the first skid, and a gas-water separator, a feeding buffer tank, a first-stage vacuum pump, an interstage buffer tank, a second-stage vacuum pump and an electric control room are mounted on the second skid; a flue gas cooler, a membrane module, a rectifying heat exchanger and a refrigerating unit cooling tower are mounted on the third skid, the lower half section of the rectifying tower is mounted on the second skid, and the upper half section of the rectifying tower is mounted on the third skid. According to the membrane method carbon capture skid-mounted device, the dismounting and mounting construction period of the carbon capture device is shortened, the equipment manufacturing precision is improved, and modular dismounting, moving, transferring and assembling of equipment are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of flue gas carbon capture devices, and in particular relates to a membrane carbon capture skid-mounted device. Background Art

[0002] CO2 is one of the most important greenhouse gases. Capturing, utilizing and storing carbon dioxide emitted in industrial production is one of the important means to reduce carbon emissions. Currently, the main technologies for flue gas carbon capture include chemical absorption, membrane separation, adsorption and other carbon capture technologies.

[0003] In medium and large-scale carbon capture systems, chemical absorption is the main method, and its equipment specifications are large, the equipment is fixed, the foundation treatment cost is high, and the land area needs to be planned in advance; for small-scale carbon capture demand scenarios, it is built in the form of medium and large-scale carbon capture systems, which has a long construction period and high construction cost. It is impossible to realize the overall relocation, transportation and assembly of the equipment, and it is difficult to produce flexibly in multiple sites.

[0004] Patent CN216418758U proposes a skid-mounted carbon dioxide capture unit based on membrane separation technology for offshore platform facilities. This unit is modified and optimized for use on offshore platforms, but the skids are arranged in parallel, underutilizing the vertical space. Patent CN218221829U proposes a small modular carbon capture system based on chemical absorption technology. The skid-mounted carbon capture system units are connected and fixed in series or parallel, enabling continuous and efficient operation. However, the absorption method's absorption and regeneration towers are relatively high, leading to numerous limitations in skid-mounted transportation. Furthermore, the liquefaction system is not considered, making the storage and utilization of captured CO2 inconvenient. Summary of the Invention

[0005] In order to solve the above-mentioned problems existing in the prior art, the purpose of the present invention is to provide a membrane carbon capture skid-mounted device, which can reduce the disassembly and installation construction period of the carbon capture device, improve the manufacturing accuracy of the equipment, realize the modular disassembly, relocation, transportation and assembly of the equipment, and realize flexible production in multiple sites.

[0006] The technical solution adopted in the present invention is:

[0007] A membrane carbon capture skid-mounted device comprises a first skid and a second skid arranged side by side on a bottom layer, a third skid being overlapped on the second skid, and a distillation tower comprising an upper half and a lower half of the distillation tower; a first-stage compressor, a second-stage compressor, a product gas compressor and a refrigeration unit compressor are installed on the first skid, a gas-water separator, a feed buffer tank, a first-stage vacuum pump, an interstage buffer tank, a second-stage vacuum pump and an electrical control room are installed on the second skid, a flue gas cooler, a membrane assembly, a distillation heat exchanger and a refrigeration unit cooling tower are installed on the third skid, the lower half of the distillation tower is installed on the second skid, and the upper half of the distillation tower is installed on the third skid.

[0008] The present invention divides the membrane carbon capture device module into three skids based on the function of the membrane carbon capture device, which facilitates the installation and transportation of the equipment. The skid-mounted device has good adaptability to carbon capture in different scenarios, and can directly capture CO2 in industrial flue gas to produce industrial-grade and food-grade purity CO2 products, with a CO2 capture rate of more than 85%. The present invention separates the compressor, vacuum pump, and membrane separation module into skids according to the operating requirements and characteristics of the equipment; according to the height characteristics of the distillation tower, the upper half of the distillation tower is arranged on the third skid, and the lower half of the distillation tower is arranged on the second skid, thereby reducing the overall height of the device. For small and medium-sized membrane carbon capture devices with a carbon capture capacity of less than 500kg / h, the solution device proposed by the present invention can shorten the on-site installation, disassembly, and transportation time by more than 50%.

[0009] As a preferred embodiment of the present invention, the control room is installed in an enclosed, independent area. Equipment other than the control room is mounted on the first, second, and third skids using a framed steel structure. This invention utilizes an open or removably enclosed skid-mounted steel structure, with flexible connections for piping between the skids. This allows for indoor installation in extremely cold regions.

[0010] As a preferred embodiment of the present invention, the membrane assembly includes a primary membrane assembly and a secondary membrane assembly.

[0011] As a preferred embodiment of the present invention, the flue gas cooler and the rectification heat exchanger are respectively plate heat exchangers or tube heat exchangers.

[0012] As a preferred embodiment of the present invention, the inlet of the flue gas cooler is connected to the flue gas inlet pipe, the outlet of the flue gas cooler is connected to the inlet of the gas-water separator through a pipe, the outlet of the gas-water separator is connected to the inlet of the first-stage compressor through a pipe, the outlet of the first-stage compressor is connected to the inlet of the feed buffer tank through a pipe, the outlet of the feed buffer tank is connected to the inlet of the first-stage membrane assembly through a pipe, the permeate gas outlet of the first-stage membrane assembly is connected to the inlet of the first-stage vacuum pump through a pipe, the outlet of the first-stage vacuum pump is connected to the inlet of the interstage buffer tank through a pipe, the outlet of the interstage buffer tank is connected to the inlet of the second-stage compressor through a pipe, the outlet of the second-stage compressor is connected to the inlet of the second-stage membrane assembly through a pipe, the permeate gas outlet of the second-stage membrane assembly is connected to the inlet of the second-stage vacuum pump through a pipe, the outlet of the second-stage vacuum pump is connected to the inlet of the product compressor through a pipe, the outlet of the product compressor is connected to the inlet of the distillation heat exchanger through a pipe, the outlet of the distillation heat exchanger is connected to the inlet of the distillation tower through a pipe, the top of the distillation tower is connected to a chimney for discharging exhaust gas, and the lower part of the distillation tower is connected to a pipe for collecting carbon dioxide products.

[0013] The flue gas is cooled to 30-50°C in a flue gas cooler and passes through a gas-water separator to remove condensed liquid water. The flue gas then enters the primary compressor, which raises the flue gas pressure to the operating pressure of the primary membrane module. In the feed buffer tank, it is mixed with the retentate gas from the secondary membrane module and subjected to molecular sieves to remove condensed water before entering the primary membrane module. The primary retentate gas from the primary membrane module has a low CO2 content and can be discharged directly through the chimney. The primary permeate gas from the primary membrane module passes through a primary vacuum pump and an interstage buffer tank before passing through a secondary compressor to raise the primary permeate gas to the operating pressure of the secondary membrane module. The secondary permeate gas enters the feed buffer tank, where the CO2 concentration in the secondary permeate gas can reach over 90% (dry basis). The secondary permeate gas is extracted by a secondary vacuum pump and then passes through a product gas compressor and a distillation heat exchanger to the required pressure and temperature for the distillation column feed. CO2 purification is completed in the distillation column to produce high-purity CO2 product. The distillation column exhaust gas is discharged directly through the chimney.

[0014] As a preferred embodiment of the present invention, the retentate gas outlet of the secondary membrane assembly is connected to the inlet of the feed buffer tank through a pipeline.

[0015] As a preferred embodiment of the present invention, the retentate gas outlet of the first-stage membrane module is connected to a chimney for discharging the first-stage retentate gas.

[0016] As a preferred embodiment of the present invention, the refrigeration unit cooling tower is connected to the refrigeration compressor via a pipeline, and the inlet and outlet of the refrigeration unit cooling tower are respectively connected to the distillation tower heat exchanger via pipelines. The cooling capacity required by the distillation heat exchanger is provided by the refrigeration unit compressor and the refrigeration unit cooling tower.

[0017] As a preferred solution of the present invention, the pipes between the first skid, the second skid and the third skid are all flexible pipes.

[0018] As a preferred solution of the present invention, the flexible pipe is a corrugated pipe or a metal braided flexible pipe.

[0019] The beneficial effects of the present invention are:

[0020] The present invention divides the membrane carbon capture device module into three skids based on the function of the membrane carbon capture device, which facilitates the installation and transportation of the equipment. The skid-mounted device has good adaptability to carbon capture in different scenarios, and can directly capture CO2 in industrial flue gas to produce industrial-grade and food-grade purity CO2 products, with a CO2 capture rate of more than 85%. The present invention separates the compressor, vacuum pump, and membrane separation module into skids according to the operating requirements and characteristics of the equipment; according to the height characteristics of the distillation tower, the upper half of the distillation tower is arranged on the third skid, and the lower half of the distillation tower is arranged on the second skid, thereby reducing the overall height of the device. For small and medium-sized membrane carbon capture devices with a carbon capture capacity of less than 500kg / h, the solution device proposed by the present invention can shorten the on-site installation, disassembly, and transportation time by more than 50%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a side view of the present invention;

[0022] Figure 2 is a top view of each skid of the present invention;

[0023] Figure 3 It is a connection structure diagram of the present invention.

[0024] In the figure: 1- flue gas cooler; 2- gas-water separator; 3- primary compressor; 4- feed buffer tank; 5- membrane assembly; 51- primary membrane assembly; 52- secondary membrane assembly; 6- primary vacuum pump; 7- interstage buffer tank; 8- secondary compressor; 9- secondary vacuum pump; 10- product gas compressor; 11- distillation heat exchanger; 12- distillation tower; 121- lower half of distillation tower; 122- upper half of distillation tower; 131- refrigeration unit compressor; 132- refrigeration unit cooling tower; 14- electrical control room. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that the embodiments of the present invention and the features therein may be combined with each other unless there is a conflict.

[0027] like Figures 1 and 2 As shown, the membrane carbon capture skid-mounted device of this embodiment includes a first skid and a second skid arranged side by side on the bottom layer, a third skid is overlapped on the second skid, and also includes a distillation tower 12, the distillation tower 12 includes an upper half 122 of the distillation tower and a lower half 121 of the distillation tower; the first skid is equipped with a first-stage compressor 3, a second-stage compressor 8, a product gas compressor 10 and a refrigeration unit compressor 131, the second skid is equipped with a gas-water separator 2, a feed buffer tank 4, a first-stage vacuum pump 6, an interstage buffer tank 7, a second-stage vacuum pump 9 and an electrical control room 14, the third skid is equipped with a flue gas cooler 1, a membrane assembly 5, a distillation heat exchanger 11 and a refrigeration unit cooling tower 132, the lower half 121 of the distillation tower is installed on the second skid, and the upper half 122 of the distillation tower is installed on the third skid.

[0028] The present invention divides the membrane carbon capture device module into three skids based on the function of the membrane carbon capture device, which facilitates the installation and transportation of the equipment. The skid-mounted device has good adaptability to carbon capture in different scenarios, and can directly capture CO2 in industrial flue gas to produce industrial-grade and food-grade purity CO2 products, with a CO2 capture rate of more than 85%. The present invention separates the compressor, vacuum pump, and membrane separation module into skids according to the operating requirements and characteristics of the equipment; according to the height characteristics of the distillation tower 12, the upper half 122 of the distillation tower is arranged on the third skid, and the lower half 121 of the distillation tower is arranged on the second skid, thereby reducing the overall height of the device. For small and medium-sized membrane carbon capture devices with a carbon capture capacity of less than 500kg / h, the solution device proposed by the present invention can shorten the on-site installation, disassembly, and transportation time by more than 50%.

[0029] The control room 14 is installed in a closed, independent area. Equipment other than the control room 14 is mounted on the first, second, and third skids using a framed steel structure. The present invention utilizes an open or removably enclosed skid-mounted steel structure. Pipes between the skids are connected using flexible connections, allowing for indoor installation in cold regions.

[0030] The membrane assembly 5 includes a primary membrane assembly 51 and a secondary membrane assembly 52 .

[0031] The flue gas cooler 1 and the rectification heat exchanger 11 are respectively plate heat exchangers or tube heat exchangers.

[0032] Specifically, if Figure 3As shown, the inlet of the flue gas cooler 1 is connected to the flue gas intake pipe, the outlet of the flue gas cooler 1 is connected to the inlet of the gas-water separator 2 through a pipe, the outlet of the gas-water separator 2 is connected to the inlet of the first-stage compressor 3 through a pipe, the outlet of the first-stage compressor 3 is connected to the inlet of the feed buffer tank 4 through a pipe, the outlet of the feed buffer tank 4 is connected to the inlet of the first-stage membrane assembly 51 through a pipe, the permeate outlet of the first-stage membrane assembly 51 is connected to the inlet of the first-stage vacuum pump 6 through a pipe, the outlet of the first-stage vacuum pump 6 is connected to the inlet of the interstage buffer tank 7 through a pipe, and the outlet of the interstage buffer tank 7 is connected to the inlet of the first-stage membrane assembly 51. The outlet is connected to the inlet of the secondary compressor 8 through a pipeline, the outlet of the secondary compressor 8 is connected to the inlet of the secondary membrane assembly 52 through a pipeline, the permeate gas outlet of the secondary membrane assembly 52 is connected to the inlet of the secondary vacuum pump 9 through a pipeline, the outlet of the secondary vacuum pump 9 is connected to the inlet of the product compressor through a pipeline, the outlet of the product compressor is connected to the inlet of the distillation heat exchanger 11 through a pipeline, the outlet of the distillation heat exchanger 11 is connected to the inlet of the distillation tower 12 through a pipeline, the top of the distillation tower 12 is connected to a chimney for discharging exhaust gas, and the lower part of the distillation tower 12 is connected to a pipeline for collecting carbon dioxide products.

[0033] The retentate gas outlet of the secondary membrane assembly 52 is connected to the inlet of the feed buffer tank 4 via a pipeline. The retentate gas outlet of the primary membrane assembly 51 is connected to a chimney for discharging the primary retentate gas. The refrigeration unit cooling tower 132 is connected to the refrigeration compressor via a pipeline. The inlet and outlet of the refrigeration unit cooling tower 132 are respectively connected to the heat exchanger of the distillation tower 12 via pipelines.

[0034] The flue gas is cooled to 30-50°C by the flue gas cooler 1. After condensed liquid water is removed by the gas-water separator 2, it enters the primary compressor 3, which raises the flue gas pressure to the operating pressure of the primary membrane assembly 51. In the feed buffer tank 4, it is mixed with the retentate gas from the secondary membrane assembly 52 and subjected to a molecular sieve to remove condensed water before entering the primary membrane assembly 51. The primary retentate gas from the primary membrane assembly 51 has a low CO2 content and can be discharged directly through the chimney. The primary permeate gas after the primary membrane assembly 51 passes through the primary vacuum pump 6 and the interstage buffer tank 7, and then passes through the secondary compressor 8, which raises the primary permeate gas to the operating pressure of the secondary membrane assembly 52. ​​The retentate gas from the secondary membrane assembly 52 enters the feed buffer tank 4, and the carbon dioxide concentration in the secondary permeate gas can reach over 90% (dry basis). The secondary permeate gas is extracted by a secondary vacuum pump 9 and then passes through a product gas compressor 10 and a distillation heat exchanger 11 to adjust the secondary permeate gas to the required pressure and temperature for feeding a distillation column 12. In distillation column 12, the CO2 is purified to form a high-purity carbon dioxide product. The exhaust gas from distillation column 12 is discharged directly through the chimney. The cooling capacity required by the distillation heat exchanger 11 is provided by the refrigeration unit compressor 131 and the refrigeration unit cooling tower 132.

[0035] Furthermore, the pipes between the first skid, the second skid and the third skid are all flexible pipes, such as corrugated pipes or metal braided flexible pipes.

[0036] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that falls within the scope defined by the claims of the present invention falls within the scope of protection of the present invention.

Claims

1. A membrane carbon capture skid-mounted device, characterized by: The invention comprises a first skid and a second skid arranged side by side on a bottom layer, a third skid being arranged on top of the second skid, and a distillation tower (12), wherein the distillation tower (12) comprises an upper half section (122) and a lower half section (121) of the distillation tower; a first-stage compressor (3), a second-stage compressor (8), a product gas compressor (10) and a refrigeration unit compressor (131) are installed on the first skid; a gas-water separator (2), a feed buffer tank (4), a first-stage vacuum pump (6), an interstage buffer tank (7), a second-stage vacuum pump (9) and an electric control room (14) are installed on the second skid; a flue gas cooler (1), a membrane assembly (5), a distillation heat exchanger (11) and a refrigeration unit cooling tower (132) are installed on the third skid; the lower half section (121) of the distillation tower is installed on the second skid, and the upper half section (122) of the distillation tower is installed on the third skid.

2. The membrane carbon capture skid-mounted device according to claim 1, characterized in that: The electric control room (14) is installed in a closed independent area, and the equipment other than the electric control room (14) on the first skid, the second skid and the third skid is installed in a frame-type steel structure.

3. The membrane carbon capture skid-mounted device according to claim 1, characterized in that: The membrane assembly (5) comprises a primary membrane assembly (51) and a secondary membrane assembly (52).

4. The membrane carbon capture skid-mounted device according to claim 1, characterized in that: The flue gas cooler (1) and the rectification heat exchanger (11) are respectively plate-type heat exchangers or tube-type heat exchangers.

5. The membrane carbon capture skid-mounted device according to claim 3, characterized in that: The inlet of the flue gas cooler (1) is connected to a flue gas inlet pipe, the outlet of the flue gas cooler (1) is connected to the inlet of the gas-water separator (2) through a pipe, the outlet of the gas-water separator (2) is connected to the inlet of the first-stage compressor (3) through a pipe, the outlet of the first-stage compressor (3) is connected to the inlet of the feed buffer tank (4) through a pipe, the outlet of the feed buffer tank (4) is connected to the inlet of the first-stage membrane assembly (51) through a pipe, the permeate outlet of the first-stage membrane assembly (51) is connected to the inlet of the first-stage vacuum pump (6) through a pipe, the outlet of the first-stage vacuum pump (6) is connected to the inlet of the interstage buffer tank (7) through a pipe, and the interstage buffer tank (7) is connected to the inlet of the first-stage membrane assembly (51). The outlet of the secondary compressor (8) is connected to the inlet of the secondary compressor (8) through a pipeline, the outlet of the secondary compressor (8) is connected to the inlet of the secondary membrane assembly (52) through a pipeline, the permeate gas outlet of the secondary membrane assembly (52) is connected to the inlet of the secondary vacuum pump (9) through a pipeline, the outlet of the secondary vacuum pump (9) is connected to the inlet of the product compressor through a pipeline, the outlet of the product compressor is connected to the inlet of the distillation heat exchanger (11) through a pipeline, the outlet of the distillation heat exchanger (11) is connected to the inlet of the distillation tower (12) through a pipeline, the top of the distillation tower (12) is connected to a chimney for discharging exhaust gas, and the lower part of the distillation tower (12) is connected to a pipeline for collecting carbon dioxide products.

6. The membrane carbon capture skid-mounted device according to claim 5, characterized in that: The retentate gas outlet of the secondary membrane assembly (52) is connected to the inlet of the feed buffer tank (4) through a pipeline.

7. The membrane carbon capture skid-mounted device according to claim 5, characterized in that: The retentate gas outlet of the first-stage membrane assembly (51) is connected to a chimney for discharging the first-stage retentate gas.

8. The membrane carbon capture skid-mounted device according to claim 5, characterized in that: The refrigeration unit cooling tower (132) is connected to the refrigeration compressor via a pipeline, and the inlet and outlet of the refrigeration unit cooling tower (132) are respectively connected to the heat exchanger of the distillation tower (12) via pipelines.

9. The membrane carbon capture skid-mounted device according to claim 5, characterized in that: The pipes between the first skid, the second skid and the third skid are all flexible pipes.

10. The membrane carbon capture skid-mounted device according to claim 9, characterized in that: The flexible pipe is a corrugated pipe or a metal braided flexible pipe.

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