A PSA tail gas compressor unit component allocation stabilizing system and method thereof

Abstract

The application discloses a PSA tail gas compressor group component allocation stabilizing system and a method thereof, and belongs to the field of chemical engineering technology. The system is characterized in that the cold box raw material gas is communicated with a first pipeline, flash gas is connected with a third pipeline, rich hydrogen gas is connected with a second pipeline of an inlet of a PSA device, CO product gas is connected with a fourth pipeline, a hydrogen gas outlet of the PSA device is connected with a fifth pipeline, a tail gas outlet sixth pipeline is connected with a seventh pipeline of an inlet of a tail gas compressor, a tail gas outlet of the tail gas compressor is connected with an eighth pipeline, a ninth pipeline of an inlet of a first regulating valve is connected with the fifth pipeline, a tenth pipeline of an outlet is connected with the sixth pipeline, an eleventh pipeline of an inlet of a second regulating valve is connected with the fourth pipeline, a twelfth pipeline of an outlet is connected with the sixth pipeline, and a thermal conductivity analyzer is arranged on the seventh pipeline. The application can realize stable PSA tail gas compressor inlet gas components by means of the thermal conductivity analyzer, the flowmeter and the regulating valve, and further ensure the performance and stable operation of the tail gas compressor.

Description

Technical Field

[0001] This invention belongs to the field of chemical technology, specifically relating to a PSA tail gas compressor component blending and stabilization system and method. Background Technology

[0002] Carbon monoxide (CO) and hydrogen (H2) are important chemical raw materials with wide applications in the chemical industry. H2, as a clean, carbon-free, flexible, and efficient new energy source, has enormous market potential in today's era of energy conservation and emission reduction. Currently, methods for separating CO and H2 include cryogenic separation and pressure swing adsorption (PSA). Cryogenic separation utilizes the difference in boiling points of gas components, achieving separation of gas mixtures through low-temperature distillation. Pressure swing adsorption utilizes the difference in selective adsorption capacity of adsorbents for different gas components under different pressure conditions, performing adsorption at relatively high pressure and desorption at low pressure to achieve gas separation and purification. PSA, with its advantages of high purity and low energy consumption, is widely used in hydrogen production.

[0003] Currently, most chemical plants use a process of cryogenic CO separation + PSA to obtain high-purity CO and H2. The upstream process syngas is used as feed gas and passes through a cryogenic CO separation cold box to obtain high-purity CO and hydrogen-rich gas. The hydrogen-rich gas passes through a PSA unit to obtain high-purity H2 and PSA tail gas. The main components of the PSA tail gas are CO and H2, which can be pressurized by the tail gas compressor and sent to the feed gas pipeline for further separation to improve the hydrocarbon recovery and utilization rate.

[0004] The instability of PSA tail gas components caused by the timing control and switching operations of the PSA unit, and the high requirements of the tail gas compressor for the stability of inlet gas components and other conditions, will have a significant impact on the stability and performance of the compressor and the entire unit if the inlet gas components and pressure fluctuate greatly. Ensuring that the inlet gas conditions of the tail gas compressor are as stable as possible has become a difficult problem for the stable operation of the compressor and the unit. Summary of the Invention

[0005] The purpose of this invention is to overcome the deficiencies in the prior art and to provide a PSA exhaust gas compressor component blending and stabilization system and method thereof.

[0006] The specific technical solution adopted in this invention is as follows:

[0007] In a first aspect, the present invention provides a PSA exhaust gas compressor component blending and stabilization system, including a cold box, a PSA device, an exhaust gas compressor, a thermal conductivity analyzer, a first regulating valve, and a second regulating valve;

[0008] The inlet of the cold box is connected to the raw material gas from the boundary area via the first pipeline; the flash vapor outlet is connected to the third pipeline; the hydrogen-rich gas outlet is connected to the hydrogen-rich gas inlet of the PSA unit via the second pipeline; and the CO product gas outlet is connected to the fourth and eleventh pipelines respectively. The hydrogen outlet of the PSA unit is connected to the fifth pipeline; and the tail gas outlet is connected to the tail gas inlet of the tail gas compressor via the sixth and seventh pipelines in sequence. The pressurized tail gas outlet of the tail gas compressor is connected to the eighth pipeline. The inlet of the first regulating valve is connected to the fifth pipeline via the ninth pipeline, and the outlet is connected to the sixth pipeline via the tenth pipeline. The inlet of the second regulating valve is connected to the eleventh pipeline, and the outlet is connected to the sixth pipeline via the twelfth pipeline.

[0009] A first flow meter is installed on the sixth pipeline adjacent to the exhaust gas outlet of the PSA unit, a second flow meter is installed on the ninth pipeline, and a third flow meter is installed on the eleventh pipeline; the thermal conductivity analyzer is installed on the seventh pipeline.

[0010] Preferably, the thermal conductivity analyzer, the first flow meter, the second flow meter, the third flow meter, the first regulating valve, and the second regulating valve are all controlled by DCS.

[0011] Preferably, the thermal conductivity analyzer is electrically connected to the second flow meter, the first regulating valve, the third flow meter, and the second regulating valve, respectively. It is used to adjust the first regulating valve and the second regulating valve according to the H2 component content in the exhaust gas compressor inlet gas obtained from the analysis, in conjunction with the second and third flow meters, so as to introduce an appropriate amount of high-purity hydrogen and / or CO product gas to stabilize the H2 component content in the exhaust gas compressor inlet gas.

[0012] Preferably, both the first regulating valve and the second regulating valve are pneumatic regulating valves.

[0013] Preferably, the first flow meter, the second flow meter, and the third flow meter are all orifice plate flow meters. Among them, the first flow meter is a flow display instrument, while the second and third flow meters are both flow indication and control instruments.

[0014] Secondly, the present invention provides a component blending and stabilization method using the PSA exhaust gas compressor component blending and stabilization system described in any one of the first aspects, as follows:

[0015] The hydrogen-rich gas in the cold box is sent to the PSA unit for hydrogen purification through the second pipeline. The high-purity hydrogen obtained is then transported outside the boundary through the fifth pipeline. The PSA tail gas discharged from the PSA unit is successively transported to the tail gas compressor through the sixth and seventh pipelines. After being pressurized by the tail gas compressor, it is transported to the upstream feed gas pipeline through the eighth pipeline. Part of the product gas CO generated in the cold box is transported to the downstream unit through the fourth pipeline, and the other part enters the second regulating valve through the eleventh pipeline for throttling, and is then transported to the sixth pipeline through the twelfth pipeline.

[0016] To stabilize the hydrogen content in the inlet gas of the exhaust compressor within a predetermined range, the H2 content in the gas is analyzed using a thermal conductivity analyzer. If the H2 content is less than the predetermined range, the opening of the first regulating valve is adjusted using a second flow meter to introduce an appropriate amount of high-purity hydrogen to increase the H2 content in the exhaust compressor inlet gas. If the H2 content is higher than the predetermined range, the opening of the second regulating valve is adjusted using a third flow meter to introduce an appropriate amount of CO product gas to decrease the H2 content in the exhaust compressor inlet gas. The flow rate of the exhaust compressor inlet gas can be calculated by summing the values ​​from the first, second, and third flow meters.

[0017] Preferably, the predetermined value ranges from 50% to 2%.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] By analyzing the hydrogen content in the gas composition using a thermal conductivity analyzer and combining this with the control and regulation of the regulating valve, the stability of the gas composition at the inlet of the exhaust gas compressor can be ensured as much as possible, thereby guaranteeing the stable operation of the exhaust gas compressor and the stable performance of the entire unit. Attached Figure Description

[0020] Figure 1 This is a flowchart of the system of the present invention.

[0021] In the diagram: cold box 101, PSA device 102, exhaust gas compressor 103, first flow meter FI100, second flow meter FIC101, third flow meter FIC102, thermal conductivity analyzer AIC100, first regulating valve FV100, second regulating valve FV101, first pipeline P1, second pipeline P2, third pipeline P3, fourth pipeline P4, fifth pipeline P5, sixth pipeline P6, seventh pipeline P7, eighth pipeline P8, ninth pipeline P9, tenth pipeline P10, eleventh pipeline P11, twelfth pipeline P12. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Technical features in various embodiments of the present invention can be combined accordingly without mutual conflict.

[0023] like Figure 1 As shown, this invention provides a PSA exhaust gas compressor component blending and stabilization system. This system can maintain the stability of the inlet gas composition of the PSA exhaust gas compressor through gas component analysis and regulating valve control, thereby ensuring the performance and stable operation of the exhaust gas compressor. The system of this invention mainly includes a cold box 101, a PSA device 102, an exhaust gas compressor 103, a first flow meter FI100, a second flow meter FIC101, a third flow meter FIC102, a thermal conductivity analyzer AIC100, a first regulating valve FV100, a second regulating valve FV101, a first pipeline P1, a second pipeline P2, a third pipeline P3, a fourth pipeline P4, a fifth pipeline P5, a sixth pipeline P6, a seventh pipeline P7, an eighth pipeline P8, a ninth pipeline P9, a tenth pipeline P10, an eleventh pipeline P11, and a twelfth pipeline P12.

[0024] The connection methods of each component will be explained in detail below.

[0025] In the system of this invention, the cold box 101 includes an inlet, a flash vapor outlet, a hydrogen-rich gas outlet, and a CO product gas outlet. The inlet is connected to a first pipeline P1, which communicates with the feed gas from the boundary area. The flash vapor outlet is connected to a third pipeline P3. The hydrogen-rich gas outlet is connected to a second pipeline P2, which is connected to the hydrogen-rich gas inlet of the PSA unit 102. The CO product gas outlet is connected to a fourth pipeline P4 and an eleventh pipeline P11.

[0026] In the system of this invention, the PSA device 102 includes a hydrogen-rich inlet, a hydrogen outlet, and a tail gas outlet. The hydrogen outlet of the PSA device 102 is connected to a fifth pipeline P5, which is used to deliver hydrogen out of the system. The tail gas outlet is connected to a sixth pipeline P6, which in turn connects to a seventh pipeline P7. The seventh pipeline P7 is connected to the tail gas inlet of the tail gas compressor 103, enabling the tail gas generated by the PSA device 102 to be fed into the tail gas compressor 103. The pressurized tail gas outlet of the tail gas compressor 103 is connected to an eighth pipeline P8, enabling the compressed tail gas to be delivered out of the system.

[0027] In the system of the present invention, the valve inlet of the first regulating valve FV100 is connected to the fifth pipeline P5 via the ninth pipeline P9, and the valve outlet of the first regulating valve FV100 is connected to the sixth pipeline P6 via the tenth pipeline P10. That is, the valve inlet and outlet of the first regulating valve FV100 are respectively connected to the fifth pipeline P5 for hydrogen outlet of PSA unit 102 and the sixth pipeline P6 for PSA tail gas outlet via the ninth pipeline P9 and the tenth pipeline P10.

[0028] In the system of this invention, the valve inlet of the second regulating valve FV101 is connected to the eleventh pipeline P11, and the valve outlet of the second regulating valve FV101 is connected to the sixth pipeline P6 via the twelfth pipeline P12. That is, the CO product gas generated by the cold box 101 is divided into two streams: one stream is sent to the downstream device and connected via the fourth pipeline P4; the other stream is connected to the inlet of the second regulating valve FV101 via the eleventh pipeline P11, and the outlet of the second regulating valve FV101 is connected to the sixth pipeline P6 of the PSA tail gas outlet via the twelfth pipeline P12.

[0029] In the system of this invention, a first flow meter FI100 is installed on the sixth pipeline P6 adjacent to the exhaust gas outlet of the PSA unit 102, a second flow meter FIC101 is installed on the ninth pipeline P9, and a third flow meter FIC102 is installed on the eleventh pipeline P11. That is, the first flow meter FI100, the second flow meter FIC101, and the third flow meter FIC102 are respectively located on the sixth pipeline P6 at the PSA exhaust gas outlet, the ninth pipeline P9 at the inlet of the first regulating valve FV100, and the eleventh pipeline P11 at the inlet of the second regulating valve FV101.

[0030] In the system of this invention, the thermal conductivity analyzer AIC100 is installed on the seventh pipeline P7, that is, the thermal conductivity analyzer AIC100 is located on the seventh pipeline P7 at the exhaust gas inlet of the exhaust gas compressor 103. In actual use, the thermal conductivity analyzer AIC100 can be electrically connected to the second flow meter FIC101, the first regulating valve FV100, the third flow meter FIC102, and the second regulating valve FV101, respectively. It is used to adjust the first regulating valve FV101 and the second regulating valve FV101 based on the H2 component content in the exhaust gas inlet gas of the exhaust gas compressor 103 obtained from the analysis, in conjunction with the second flow meter FIC101 and the third flow meter FIC102, thereby introducing an appropriate amount of high-purity hydrogen and / or CO product gas to stabilize the H2 component content in the exhaust gas inlet gas of the exhaust gas compressor 103.

[0031] In a preferred embodiment of the present invention, the thermal conductivity analyzer AIC100, the first flow meter FI100, the second flow meter FIC101, the third flow meter FIC102, the first regulating valve FV100, and the second regulating valve FV101 are all controlled by DCS.

[0032] In a preferred embodiment of the present invention, both the first regulating valve FV100 and the second regulating valve FV101 are pneumatic regulating valves. The first flow meter FI100, the second flow meter FIC101, and the third flow meter FIC102 are all orifice plate flow meters, wherein the first flow meter FI100 is a flow display instrument, and the second flow meter FIC101 and the third flow meter FIC102 are both flow indication and control instruments.

[0033] Based on the above-mentioned PSA exhaust gas compressor component blending and stabilization system, the present invention also provides a component blending and stabilization method, which is as follows:

[0034] The hydrogen-rich gas in the cold box 101 is sent to the PSA unit 102 via the second pipeline P2 for hydrogen purification. The high-purity hydrogen obtained is then transported outside the boundary via the fifth pipeline P5. The PSA tail gas discharged from the PSA unit 102 is sequentially transported to the tail gas compressor 103 via the sixth pipeline P6 and the seventh pipeline P7. After being pressurized by the tail gas compressor 103, it is transported to the upstream feed gas pipeline via the eighth pipeline P8. Part of the product gas CO generated in the cold box 101 is transported to the downstream unit via the fourth pipeline P4, and the other part enters the second regulating valve FV101 via the eleventh pipeline P11 for throttling, and then is transported to the sixth pipeline P6 via the twelfth pipeline P12.

[0035] To stabilize the hydrogen content in the inlet gas of the exhaust compressor 103 within a predetermined range, the H2 content in the gas is analyzed using a thermal conductivity analyzer AIC100. If the H2 content is less than the predetermined range, the opening of the first regulating valve FV100 is adjusted using the second flow meter FIC101 to introduce an appropriate amount of high-purity hydrogen to increase the H2 content in the inlet gas of the exhaust compressor 103. If the H2 content is higher than the predetermined range, the opening of the second regulating valve FV101 is adjusted using the third flow meter FIC102 to introduce an appropriate amount of CO product gas to decrease the H2 content in the inlet gas of the exhaust compressor 103.

[0036] As a preferred embodiment of the present invention, the system can be pre-set with an automatic calculation feedback program. After the H2 content in the gas is analyzed by the thermal conductivity analyzer AIC100, the program can automatically calculate the amount of hydrogen and carbon monoxide that need to be added based on the H2 component content, and then control the second flow meter FIC101 and the third flow meter FIC102 to perform corresponding actions.

[0037] The following examples will illustrate the component formulation and stabilization method of the present invention.

[0038] Example

[0039] This embodiment is based on Figure 1The aforementioned PSA exhaust gas compressor component blending and stabilization system provides a component blending and stabilization method, which is as follows:

[0040] The hydrogen-rich gas (H2 content of 85%) from the cold box is sent to the inlet of PSA unit 102 for hydrogen purification. The high-purity hydrogen is then transported to the outside of the boundary via the fifth hydrogen outlet pipeline P5. The PSA tail gas (H2 content of 50%±2%) is sent from the sixth tail gas outlet pipeline P6 to the seventh tail gas compressor inlet pipeline P7. After being pressurized by the tail gas compressor 103, it is sent to the upstream feed gas pipeline. A branch pipeline is provided on the fifth hydrogen outlet pipeline P5 of PSA unit 102, namely the ninth pipeline P9 and the tenth pipeline P10 connected in sequence. The ninth pipeline P9 is equipped with a first regulating valve FV100. The CO product gas from the cold box is divided into two streams: one stream is sent to the downstream unit, and the other stream is throttled by the second regulating valve FV101 and sent to the sixth PSA tail gas outlet pipeline P6. To stabilize the hydrogen content in the inlet gas of the exhaust compressor 103 at 50%±2%, the H2 content in the gas is analyzed by a thermal conductivity analyzer AIC100 on the seventh inlet pipe P7 of the exhaust compressor 103. If the H2 content is less than 50%±2%, the required amount of H2 to be added is determined by a pre-set system program. This H2, in conjunction with the second flow meter FIC101, adjusts the valve opening of the first regulating valve FV100 on the hydrogen outlet branch of the PSA unit 102, introducing an appropriate amount of high-purity hydrogen to increase the H2 content in the inlet gas of the exhaust compressor 103. If the H2 content is higher than 50%±2%, the required amount of CO to be added is determined by a pre-set system program. This CO, in conjunction with the third flow meter FIC102, adjusts the valve opening of the second regulating valve FV101 on the eleventh CO product gas pipe P11, introducing an appropriate amount of CO product gas to reduce the H2 content in the inlet gas of the exhaust compressor 103.

[0041] In the above process, the flow rate of the gas at the inlet of the exhaust gas compressor 103 can be calculated by adding the values ​​displayed by the first flow meter FI100, the second flow meter FIC101 and the third flow meter FIC102.

[0042] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.

Claims

1. A PSA exhaust gas compressor component blending and stabilization system, characterized in that, Includes a cold box (101), a PSA unit (102), an exhaust gas compressor (103), a thermal conductivity analyzer (AIC100), a first regulating valve (FV100), and a second regulating valve (FV101); The inlet of the cold box (101) is connected to the raw material gas from the boundary area via the first pipeline (P1), the flash vapor outlet is connected to the third pipeline (P3), the hydrogen-rich gas outlet is connected to the hydrogen-rich gas inlet of the PSA unit (102) via the second pipeline (P2), and the carbon monoxide product gas outlet is connected to the fourth pipeline (P4) and the eleventh pipeline (P11) respectively; the hydrogen outlet of the PSA unit (102) is connected to the fifth pipeline (P5), and the tail gas outlet is connected to the sixth pipeline (P6) and the seventh pipeline (P11) in sequence. 7) Connected to the exhaust gas inlet of the exhaust gas compressor (103); the pressurized exhaust gas outlet of the exhaust gas compressor (103) is connected to the eighth pipeline (P8); the inlet of the first regulating valve (FV100) is connected to the fifth pipeline (P5) through the ninth pipeline (P9), and the outlet is connected to the sixth pipeline (P6) through the tenth pipeline (P10); the inlet of the second regulating valve (FV101) is connected to the eleventh pipeline (P11), and the outlet is connected to the sixth pipeline (P6) through the twelfth pipeline (P12); A first flow meter (FI100) is installed on the sixth pipeline (P6) adjacent to the exhaust gas outlet of the PSA unit (102); a second flow meter (FIC101) is installed on the ninth pipeline (P9); and a third flow meter (FIC102) is installed on the eleventh pipeline (P11); the thermal conductivity analyzer (AIC100) is installed on the seventh pipeline (P7); The thermal conductivity analyzer (AIC100) is electrically connected to the second flow meter (FIC101), the first regulating valve (FV100), the third flow meter (FIC102), and the second regulating valve (FV101), respectively. It is used to calculate the required supplementary flow rate based on the hydrogen component content in the inlet gas of the tail gas compressor (103) obtained from the analysis. At the same time, it is used in conjunction with the second flow meter (FIC101) and the third flow meter (FIC102) to adjust the first regulating valve (FV100) and the second regulating valve (FV101), thereby introducing high-purity hydrogen and / or carbon monoxide product gas to stabilize the hydrogen component content in the inlet gas of the tail gas compressor (103).

2. The PSA exhaust gas compressor component blending and stabilization system according to claim 1, characterized in that, The thermal conductivity analyzer (AIC100), the first flow meter (FI100), the second flow meter (FIC101), the third flow meter (FIC102), the first regulating valve (FV100), and the second regulating valve (FV101) are all controlled by DCS.

3. The PSA exhaust gas compressor component blending and stabilization system according to claim 1, characterized in that, Both the first regulating valve (FV100) and the second regulating valve (FV101) are pneumatic regulating valves.

4. The PSA exhaust gas compressor component blending and stabilization system according to claim 1, characterized in that, The first flow meter (FI100), the second flow meter (FIC101), and the third flow meter (FIC102) are all orifice plate flow meters; among them, the first flow meter (FI100) is a flow display instrument, and the second flow meter (FIC101) and the third flow meter (FIC102) are both flow indication and control instruments.

5. A method for component blending and stabilization using the PSA exhaust gas compressor component blending and stabilization system according to any one of claims 1 to 4, characterized in that, Specifically as follows: The hydrogen-rich gas in the cold box (101) is sent to the PSA unit (102) through the second pipeline (P2) for hydrogen purification. The high-purity hydrogen obtained is transported to the outside of the boundary through the fifth pipeline (P5). The PSA tail gas discharged from the PSA unit (102) is transported to the tail gas compressor (103) through the sixth pipeline (P6) and the seventh pipeline (P7) in sequence. After being pressurized by the tail gas compressor (103), it is transported to the upstream raw material gas pipeline through the eighth pipeline (P8). Part of the carbon monoxide product gas generated in the cold box (101) is transported to the downstream unit through the fourth pipeline (P4), and the other part enters the second regulating valve (FV101) through the eleventh pipeline (P11) for throttling, and then is transported to the sixth pipeline (P6) through the twelfth pipeline (P12). To ensure the hydrogen content in the inlet gas of the exhaust compressor (103) remains within a predetermined range, the hydrogen content in the gas is analyzed using a thermal conductivity analyzer (AIC100). If the hydrogen content is less than the predetermined range, the valve opening of the first regulating valve (FV100) is adjusted using the second flow meter (FIC101) to introduce the required high-purity hydrogen and increase the hydrogen content in the inlet gas of the exhaust compressor (103). If the hydrogen content is higher than the predetermined range, the valve opening of the second regulating valve (FV101) is adjusted using the third flow meter (FIC102) to introduce the required carbon monoxide product gas and decrease the hydrogen content in the inlet gas of the exhaust compressor (103). The flow rate of the inlet gas of the exhaust compressor (103) can be calculated using the first flow meter (FI100), the second flow meter (FIC101), and the third flow meter (FIC102).

6. The component blending and stabilization method according to claim 5, characterized in that, The predetermined value range is 50% ± 2%.

Images