A liquid methanol collection system

Abstract

The present invention relates to a methanol collection system, and more specifically, to a liquid methanol collection system, comprising: a carbon dioxide compressor, a separation device, a methanol collection device and a cold box; the separation device is connected to the carbon dioxide compressor; the methanol collection device is connected to the separation device, the methanol collection device is connected to a second pipeline, the second pipeline is connected to a condensation venting pipeline, and a flare system for burning methanol gas is arranged on the condensation venting pipeline; the condensation venting pipeline is arranged in the cold box, and the condensation venting pipeline is connected to a third pipeline; the third pipeline is connected to the first pipeline through a secondary reflux pipeline. The present invention effectively solves the problem that the carbon dioxide raw gas contains a large amount of saturated methanol gas, realizes the liquefaction, collection and storage of saturated methanol gas in the carbon dioxide raw gas, and ensures the safe production of the device and the safety of operators.

Description

Technical Field

[0001] The present invention relates to a methanol collection system, and more particularly to a liquid methanol collection system. Background Art

[0002] In the coal-to-hydrogen system, the coal-to-hydrogen device often operates at a large load or overload, which leads to abnormal operating conditions of the entire system, causing the carbon dioxide raw gas to carry about 2% saturated methanol gas. After the carbon dioxide-methanol mixed gas is compressed and condensed by the carbon dioxide compressor, a large amount of liquid methanol is precipitated from the condensate discharge valve. Methanol is toxic and has the greatest impact on the human nervous system and blood system. It will produce toxic reactions when ingested through the digestive tract, respiratory tract or skin, damaging the respiratory mucosa and vision of the human body.

[0003] Therefore, in order to avoid safety and environmental accidents caused by the discharge of large amounts of liquid methanol at the coal-to-hydrogen site, the liquid methanol must be collected in a targeted manner to solve the problem of the carbon dioxide raw gas containing a large amount of saturated methanol gas, ensuring the safety of personnel and safe production of the equipment. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a liquid methanol collection system, which effectively solves the problem that the carbon dioxide raw gas contains a large amount of saturated methanol gas, realizes the liquefaction, collection and storage of the saturated methanol gas in the carbon dioxide raw gas, and ensures the safe production of the device and the safety of the operators.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: a liquid methanol collection system, comprising:

[0006] A separation device, wherein the separation device is connected to a carbon dioxide compressor;

[0007] A methanol collecting device, wherein the methanol collecting device is connected to the separation device via a first pipeline, the methanol collecting device is connected to a second pipeline, the other end of the second pipeline away from the methanol collecting device is connected to a condensation venting pipeline, and a flare system for burning methanol gas is provided on the condensation venting pipeline;

[0008] The cold box, the condensation venting pipeline is arranged in the cold box, the condensation venting pipeline is connected to the third pipeline; the third pipeline is connected to the secondary reflux pipeline, and the outlet of the secondary reflux pipeline is connected to the first pipeline.

[0009] In one of the embodiments, a U-shaped water seal section for water sealing is provided on the second pipeline.

[0010] In one of the embodiments, a shower guide pipe is provided at the lowest point of the U-shaped water seal section of the second pipeline, and a shower guide valve is provided on the shower guide pipe.

[0011] In one of the embodiments, a flame arrester is provided on the second pipeline.

[0012] In one of the embodiments, a water seal inlet pipe is also provided on the second pipeline.

[0013] In one embodiment, the outlet of the third pipeline is also connected to a carbon dioxide venting pipeline.

[0014] In one of the embodiments, a secondary recooler is also provided on the third pipeline.

[0015] In one embodiment, the separation device, the methanol collection device, the cold box, the first pipeline, the second pipeline and the third pipeline are also connected to a grounded electrostatic device.

[0016] The advantages of the present invention are:

[0017] (1) According to the present invention, after the carbon dioxide-methanol mixed gas is compressed by three stages of a carbon dioxide compressor, it enters a separation device for gas-liquid separation, and then the separated liquid methanol enters a methanol collection device for collection and storage, while the unliquefied methanol gas enters the second pipeline along with the carbon dioxide gas and is burned through a flare system, and part of the unburned methanol liquid is condensed in a cold box and then returned to the methanol collection device, thereby realizing the liquefaction, separation, collection and storage of the methanol gas in the carbon dioxide raw gas, and ensuring the safe production of the device and the safety of the operators.

[0018] (2) The second pipeline of the present invention is also provided with a flame arrester. When the flare system burns methanol gas, the flame arrester can prevent external flames from entering the methanol collection device containing flammable and explosive methanol liquid, thereby ensuring the safety of the device during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the present invention.

[0020] In the figure, 1. Separation device; 2. Methanol collection device; 3. Cold box; 4. Flare system; 5. First pipeline; 6.

[0021] Second pipeline; 7. Condensation vent pipeline; 8. Third pipeline; 9. Secondary recooler; 10. Carbon dioxide vent pipeline; 11. Secondary reflux pipeline; 12. Flame arrester; 13. Drain pipe; 14. Drain valve; 15. Water seal inlet pipe; 16. Manual control valve; 17. Carbon dioxide compressor. DETAILED DESCRIPTION

[0022] like Figure 1As shown, a liquid methanol collection system includes a separation device 1, a methanol collection device 2, a cold box 3, a flare system 4 and a carbon dioxide compressor 17.

[0023] The separation device 1 comprises an inlet and an outlet. The inlet of the separation device 1 is connected to the tertiary compression outlet of the carbon dioxide compressor 17 , and the outlet of the separation device 1 is connected to the first pipeline 5 .

[0024] The methanol collecting device 2 includes an inlet and an outlet. The inlet of the methanol collecting device 2 is connected to one end of the first pipeline 5 away from the outlet of the separation device 1, and the outlet of the methanol collecting device 2 is connected to the second pipeline 6. The end of the second pipeline 6 away from the outlet of the methanol collecting device 2 is connected to a condensation venting pipeline 7, which is arranged in the cold box 3 and connected to the third pipeline 8. A flare system 4 for burning methanol gas is arranged at the end of the condensation venting pipeline 7. The flare system 4 is used to burn methanol gas to ensure that the exhaust gas meets environmental protection standards, ensure factory safety production, and reduce environmental pollution.

[0025] The third pipeline 8 is provided with a secondary recooler 9 , and the outlet of the third pipeline 8 is respectively connected to a carbon dioxide venting pipeline 10 and a secondary reflux pipeline 11 , and one end of the secondary reflux pipeline 11 away from the third pipeline 8 is connected to the first pipeline 5 .

[0026] Furthermore, a flame arrester 12 is provided on the second pipeline 6. Specifically, the flame arrester 12 is a flange-type flame arrester with a specification of PN1.6 and DN100. When the flare system 4 burns methanol gas, the flame arrester 12 can prevent external flames from entering the methanol collection device 2 containing flammable and explosive liquid methanol.

[0027] Furthermore, a U-shaped water seal section for water sealing is provided on the second pipeline 6 .

[0028] Furthermore, a drainage pipe 13 is provided at the lowest part of the U-shaped water seal section of the second pipeline 6, and a drainage valve 14 is provided on the drainage pipe 13. The specification of the drainage valve 14 is PN1.6, DN25. The drainage valve 14 is provided at the lowest part of the U-shaped water seal section. When it is necessary to stop the work for maintenance or re-inspection, the residual liquid in the second pipeline 6 can be drained through the drainage pipe 13.

[0029] Furthermore, the liquid methanol collection system also includes a toxic gas online monitor for monitoring the methanol gas content. The staff can monitor the methanol gas content in real time. When the methanol gas content in the room exceeds the standard, the staff can discover it in the first time and take emergency measures.

[0030] Furthermore, the liquid methanol collection safety system also includes a fire sprinkler device, which is arranged above the flare system 4.

[0031] Furthermore, a water seal inlet pipe 15 is also provided on the second pipeline 6, and the water seal inlet pipe 15 includes an upper water seal inlet pipe and a lower water seal inlet pipe.

[0032] Furthermore, ball valves are provided on the upper water seal inlet pipe 171, the lower water seal inlet pipe 172 and the shower pipe 13; stop valves are provided on the first pipeline 5, the second pipeline 6, the third pipeline 8, the carbon dioxide venting pipeline 10 and the secondary return pipeline 11, and a manual control valve 16 is also provided on the third pipeline 8.

[0033] Furthermore, the separation device 1, the methanol collection device 2, the cold box 3, the first pipeline 5, the second pipeline 6, and the third pipeline 8 are also connected to a grounded electrostatic device to prevent the device or pipeline from generating static electricity.

[0034] Furthermore, the methanol collecting device 2 is a pressure vessel, the volume capacity of the methanol collecting device 2 is 5 to 10 m3, and the material is Q345 carbon steel; the separation device 1 is a three-stage separator of a carbon dioxide compressor.

[0035] Furthermore, the specifications of the first pipeline 5 and the third pipeline 8 are DN25, the specifications of the second pipeline 6 and the condensation vent pipeline 7 are DN100, and the absolute height of the condensation vent pipeline 7 is 30-35 m.

[0036] The working principle of the present invention is as follows: the carbon dioxide raw gas with saturated methanol gas is firstly compressed in three stages by a carbon dioxide compressor 17, so that the saturated methanol gas in the carbon dioxide raw gas is compressed into liquid. The compression method of multi-stage compression can be close to isothermal compression on the one hand, avoiding the temperature rise in the gas compression process, so that the liquefied methanol is gasified again; on the other hand, the volume utilization rate of the container can be improved. The gas-liquid mixture after the three-stage compression by the carbon dioxide compressor 17 enters the separation device 1 for gas-liquid separation, and the liquid methanol flows into the methanol collecting device 2 through the first pipeline 5 and is collected and stored in the methanol collecting device 2, and part of the carbon dioxide-methanol gas mixture also flows into the methanol collecting device 2 through the first pipeline 5 and enters the second pipeline 6 and the condensation and venting pipeline 7 through the top outlet of the methanol collecting device 2, wherein part of the methanol gas is burned at the tail end of the condensation and venting pipeline to generate carbon dioxide and water through the torch system 4, and the remaining part of the methanol gas is condensed into liquid through the cold box 3, and then the methanol gas is refluxed to the methanol collecting device 2 through the third pipeline 8 and the secondary reflux pipeline 11 by controlling the switch of the stop valve or the manual control valve 18 to be collected and stored. The carbon dioxide flows into the next process through the carbon dioxide venting pipeline 10.

[0037] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A liquid methanol collection system, characterized in that: include: A separation device (1), wherein the separation device (1) is connected to a carbon dioxide compressor (17); A methanol collecting device (2), wherein the methanol collecting device (2) is connected to the separation device (1) via a first pipeline (5), the methanol collecting device (2) is connected to a second pipeline (6), the other end of the second pipeline (6) away from the methanol collecting device (2) is connected to a condensation venting pipeline (7), and the condensation venting pipeline (7) is provided with a flare system (4) for burning methanol gas; The second pipeline (6) is provided with a flame arrester (12); the second pipeline (6) is provided with a U-shaped water seal section for water sealing; A cold box (3), wherein the condensate venting pipeline (7) is arranged in the cold box (3), and the condensate venting pipeline (7) is connected to a third pipeline (8); the third pipeline (8) is connected to a secondary reflux pipeline (11), and the outlet of the secondary reflux pipeline (11) is connected to the first pipeline (5).

2. The liquid methanol collection system according to claim 1, characterized in that: A shower guide pipe (13) is provided at the lowest point of the U-shaped water seal section of the second pipeline (6), and a shower guide valve (14) is provided on the shower guide pipe (13).

3. The liquid methanol collection system according to claim 1, characterized in that: The second pipeline (6) is provided with a water seal inlet pipe (15).

4. The liquid methanol collection system according to claim 1, characterized in that: The outlet of the third pipeline (8) is also connected to a carbon dioxide venting pipeline (10).

5. The liquid methanol collection system according to claim 1, characterized in that: The third pipeline (8) is also provided with a secondary recooler (9).

6. The liquid methanol collection system according to claim 1, characterized in that: The separation device (1), the methanol collection device (2), the cold box (3), the first pipeline (5), the second pipeline (6) and the third pipeline (8) are also connected to a grounded electrostatic device.

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