Membrane condensation recovery device for 1, 1-dichloroethylene organic waste gas
By treating 1,1-dichloroethylene organic waste gas with acid removal and demisting, combined with the automatic control of buffer tanks and gas-liquid separators, the problems of pH value, water content and liquid level management in existing equipment have been solved, achieving efficient and safe waste gas treatment and recovery.
Patent Information
- Application Number
- CN202423059132.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-12-11
Smart Images
Figure CN223490450U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of waste gas treatment technology, specifically relating to a membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas. Background Technology
[0002] In the current field of industrial waste gas treatment, especially in the treatment of organic waste gases such as 1,1-dichloroethylene, there are a series of technical challenges and shortcomings. As a typical volatile organic compound (VOC), the treatment of 1,1-dichloroethylene waste gas is not only related to environmental protection but also directly affects production safety and efficiency. However, existing waste gas treatment devices often neglect the control of several key factors when treating such waste gases, factors that are crucial to ensuring treatment effectiveness and stable system operation.
[0003] First, the pH value, moisture content, and temperature of the waste gas are important parameters affecting the behavior of its components. Current technologies for treating this type of waste gas lack control over these indicators, leading to the agglomeration of 1,1-dichloroethylene and other components within the condensation and recovery unit, reducing recovery efficiency. Simultaneously, large temperature fluctuations also affect the condensation effect, causing some waste gas to escape without effective condensation, or excessive condensation leading to increased energy consumption.
[0004] Secondly, as a key component in the condensation recovery unit, the stability of the liquid level in the gas-liquid separator directly affects the efficiency and safety of waste gas treatment. In actual operation, improper liquid level control in the gas-liquid separator can lead to "gas-liquid carryover," where excessive liquid is carried into subsequent processing units. This not only reduces the purity of the recovered liquid but may also cause corrosion or blockage of downstream equipment. Conversely, a low liquid level may prevent condensable components in the gas from fully contacting the condensate, affecting recovery efficiency. Furthermore, a low liquid level can cause pressure fluctuations inside the container, affecting the stable operation of the entire system. Unstable pressure not only reduces processing efficiency but may also lead to safety hazards such as equipment leaks or unexpected shutdowns.
[0005] In summary, existing 1,1-dichloroethylene organic waste gas treatment devices suffer from a series of problems during the treatment process due to neglect of pH, moisture content, temperature control, and gas-liquid separator level management. These problems include waste gas component agglomeration, liquid carryover in the gas, pipe blockage, and unstable pressure within the container. These issues not only affect the efficiency and quality of waste gas treatment but also increase operating costs and safety risks. Therefore, developing a membrane condensation and recovery device capable of precisely controlling these key parameters to ensure efficient, stable, and safe treatment of 1,1-dichloroethylene organic waste gas is of paramount importance. Utility Model Content
[0006] To address the problems of existing technologies, this invention provides a membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas.
[0007] The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas of this utility model includes a vinyl chloride waste gas feedstock pipeline. The vinyl chloride waste gas feedstock pipeline is connected to a demister via a deacidification tower. The demister is connected to a buffer tank. The buffer tank is connected to a gas-liquid separator via a compressor. The gas-liquid separator is connected to a condenser via a precooler. The condenser is connected to a collection tank. The collection tank is connected to the precooler via a non-condensable gas pipeline. The precooler is connected to a membrane separation system. The upstream of the membrane of the membrane separation system is connected to an oxygen-based cracking system via a dilute tail gas transport pipeline. The downstream of the membrane of the membrane separation system is connected to the buffer tank via an organic volatile gas transport pipeline. The gas-liquid separator is equipped with a working fluid circulation pipeline. A heat exchanger is installed on the working fluid circulation pipeline. A compressor outlet temperature transmitter is installed on the compressor outlet pipeline. A first drain pipeline is installed at the bottom of the gas-liquid separator. A working fluid replenishment pipeline is installed on the gas-liquid separator. A pH meter is installed on the working fluid circulation pipeline.
[0008] This invention first treats the vinyl chloride waste gas emitted during the production process by removing acid and mist, ensuring that the pH is between 7.5 and 9.5 and the water content is ≤6%, thereby reducing or eliminating the risk of waste gas components agglomerating in the device.
[0009] The compressor head outlet temperature transmitter monitors the temperature of the exhaust gas at the compressor outlet. If the temperature exceeds the set temperature, the system will automatically alarm and shut down.
[0010] The buffer tank is equipped with a pressure transmitter, which is interlocked with the compressor's frequency converter. The compressor can automatically adjust its operating frequency to match the air extraction volume with the incoming air volume, thereby saving energy and stabilizing system operation.
[0011] This invention incorporates a buffer tank to buffer pressure. Before the exhaust gas enters the compressor, the buffer tank absorbs and releases pressure fluctuations, ensuring stable gas pressure entering the compressor and preventing damage or efficiency loss due to sudden pressure changes. The mixing of volatile organic compounds (VOCs) generated downstream of the membrane separation system with the original exhaust gas in the buffer tank helps achieve a more uniform component distribution, reducing efficiency loss or equipment blockage caused by uneven component distribution.
[0012] The pH meter is used to monitor whether the pH of the circulating working fluid in the working fluid circulation pipeline is maintained between 7.5 and 9.5. When the pH does not meet the set requirements, the pH of the working fluid in the gas-liquid separator is adjusted.
[0013] Furthermore, the compressor is equipped with a compressor head soft water pipeline and a compressor head temperature transmitter.
[0014] Furthermore, the gas-liquid separator is equipped with a first level transmitter, a valve is provided on the first drain line, a valve is provided on the working fluid replenishment line, and the output terminal of the first level transmitter is electrically connected to the control terminal of the valve on the first drain line and the valve on the working fluid replenishment line.
[0015] The liquid level inside the gas-liquid separator can be automatically controlled within a certain range. If the liquid level is too high, it will automatically drain from the bottom; if the liquid level is too low, it will automatically replenish the working fluid.
[0016] When the liquid level is too high, if liquid enters the gas pipeline, it can cause blockage, affecting the normal flow of gas. This not only reduces the system's processing efficiency but may also lead to safety accidents. Conversely, if the liquid level is too low, it may cause liquid entrainment in the gas. This not only reduces the purity of the gas but also damages downstream equipment, affecting its normal operation.
[0017] Changes in liquid level affect the pressure distribution inside the gas-liquid separator. Maintaining the liquid level within a certain range helps to stabilize the system pressure, thereby ensuring the normal operation of the entire system.
[0018] Furthermore, the outlet of the gas-liquid separator is equipped with a demister.
[0019] Furthermore, the liquid collection tank is equipped with a second liquid level transmitter, the bottom of the liquid collection tank is equipped with a second drain line, the second drain line is equipped with a valve, and the output terminal of the second liquid level transmitter is electrically connected to the control terminal of the valve on the second drain line.
[0020] Similarly, when the liquid level in the collection tank is too high, it will automatically drain from the bottom.
[0021] Furthermore, the first and second drain lines are connected to a solvent recovery device.
[0022] Furthermore, a vacuum pump is installed on the organic volatile gas transport pipeline.
[0023] Working principle:
[0024] The vinyl chloride waste gas emitted during the production process first undergoes deacidification and demisting treatment to ensure a pH of 7.5-9.5 and a water content of ≤6%. It then enters a buffer tank through a pipeline equipped with a flame arrester. A pressure transmitter installed on the buffer tank is interlocked with the compressor's frequency converter, allowing the compressor to automatically adjust its operating frequency to match the intake gas volume. Before starting the compressor, soft water is used to replenish the working fluid to the compressor head via the compressor head soft water pipeline, and the fluid level is confirmed to be at the compressor head shaft center. Subsequently, the valve on the compressor head soft water pipeline is closed, and the valve on the working fluid replenishment pipeline is opened to replenish the working fluid to the gas-liquid separator. (Soft water) Once the first liquid level sensor set value is reached, the valve is closed. After confirming that the working fluid circulation pipeline connected to the gas-liquid separator is full of working fluid, the compressor is started. Exhaust gas and working fluid are sprayed from the compressor outlet into the gas-liquid separator. The heat exchanger on the working fluid circulation pipeline uses industrial circulating water as a cold source. When the compressor outlet gas temperature exceeds the set temperature, the system will automatically alarm or even shut down. Exhaust gas and working fluid enter the gas-liquid separator, where gas, water, and oil achieve three-phase self-separation. Chlorinated hydrocarbon liquid is at the bottom of the tank, water is in the middle layer, and the upper gas passes through the demister at the top of the tank and enters the downstream condensation system. The liquid level in the gas-liquid separator is automatically controlled within a certain range. If the liquid level is too high, it will automatically drain from the bottom; if the liquid level is too low, it will automatically replenish the working fluid (water). After the gas is discharged from the top of the gas-liquid separator, it enters the condensation system, which includes a precooler and a condenser. The main purpose of the precooler is to improve waste heat utilization efficiency and maximize energy savings. The non-condensable gas discharged from the condenser exchanges heat with the gas from the separator in the precooler, increasing the temperature of the non-condensable gas entering the membrane and simultaneously lowering the temperature of the tail gas / waste liquid mixture entering the condenser. The plate condenser here uses refrigerant as the cold source, maintaining the non-condensable gas outlet temperature between 7-12℃. In the condenser, the vapor partial pressure of organic gases will significantly exceed their corresponding saturated vapor partial pressure, causing them to liquefy and enter the collection tank. Similar to the gas-liquid separator, the liquid level in the collection tank is automatically controlled within a certain range; if the level is too high, liquid will automatically drain from the bottom. The condensed gas enters the membrane separation system, whose main function is to enrich the small amount of volatile organic components contained in the non-condensable gas. Driven by the partial pressure difference of organic matter upstream and downstream of the membrane system, the rate at which volatile organic gases in the non-condensable gas permeate the membrane is significantly higher than that of air, allowing organic matter to be enriched downstream. This is then transported by a vacuum pump to a buffer tank, and then to the compressor inlet for further processing. The organic matter content in the tail gas that does not permeate the membrane is greatly reduced, and it then enters the oxygen-based pyrolysis system for further treatment to ultimately achieve emission standards.
[0025] The beneficial effects of this utility model are as follows:
[0026] (1) Before treating the waste gas, the present invention first deacidifies and demistates the vinyl chloride waste gas emitted during the production process to ensure that the pH is 7.5-9.5 and the water content is ≤6%, thereby reducing or eliminating the risk of waste gas components agglomerating in the device.
[0027] (2) The compressor head outlet temperature transmitter of the present invention monitors the temperature of the exhaust gas at the compressor outlet. If the temperature exceeds the set temperature, the system will automatically alarm and shut down. This achieves strict temperature monitoring and improves recovery efficiency.
[0028] (3) This utility model is equipped with a buffer tank, which serves as a pressure buffer. Before the waste gas enters the compressor, the buffer tank can absorb and release pressure fluctuations, ensuring that the gas pressure entering the compressor is stable and preventing the compressor from being damaged or its efficiency from decreasing due to sudden pressure changes. The organic volatile gas generated downstream of the membrane separation system mixes with the original waste gas in the buffer tank, which helps to achieve a more uniform component distribution and reduces the problem of decreased treatment efficiency or equipment blockage caused by uneven component distribution.
[0029] (4) The liquid level in the gas-liquid separator of this utility model can be automatically controlled within a certain range. If the liquid level is too high, it will automatically drain from the bottom, and if the liquid level is too low, it will automatically replenish the working fluid. Attached Figure Description
[0030] The accompanying drawings, which are included to provide a further understanding of the present invention, form part of this invention. In the drawings:
[0031] Figure 1 This is a schematic diagram of the membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to this utility model.
[0032] In the diagram: 1. Buffer tank; 2. Vinyl chloride waste gas feedstock pipeline; 3. Compressor; 301. Die head temperature transmitter; 302. Die head soft water pipeline; 4. Die head outlet temperature transmitter; 5. Gas-liquid separator; 501. First liquid level transmitter; 502. Working fluid replenishment pipeline; 503. Demister; 6. Working fluid circulation pipeline; 601. pH meter; 7. Heat exchanger; 8. Precooler; 9. Condenser; 10. Collection tank; 1001. Second liquid level transmitter; 1002. Non-condensable gas pipeline; 11. Membrane separation system; 12. Organic volatile gas transport pipeline; 13. Concentrated tail gas transport pipeline; 14. Oxygen-containing cracking system; 15. Vacuum pump; 16. First drain pipeline; 17. Second drain pipeline; 18. Solvent recovery device; 19. Deacidification tower; 20. Demister. Detailed Implementation
[0033] The present invention will be explained in detail below with reference to the embodiments.
[0034] Example 1
[0035] like Figure 1As shown, the membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas includes a vinyl chloride waste gas feedstock pipeline 2. The vinyl chloride waste gas feedstock pipeline 2 is connected to a demister 20 via a deacidification tower 19. The demister 20 is connected to a buffer tank 1. The buffer tank 1 is connected to a gas-liquid separator 5 via a compressor 3. The gas-liquid separator 5 is connected to a condenser 9 via a precooler 8. The condenser 9 is connected to a collection tank 10. The collection tank 10 is connected to the precooler 8 via a non-condensable gas pipeline 1002. The precooler 8 is connected to a membrane separation system 11. The membrane of the membrane separation system 11... The upstream part is connected to the oxygen cracking system 14 via the enriched tail gas transport pipeline 13. The downstream part of the membrane separation system 11 is connected to the buffer tank 1 via the organic volatile gas transport pipeline 12. The gas-liquid separator 5 is equipped with a working fluid circulation pipeline 6, and a heat exchanger 7 is installed on the working fluid circulation pipeline 6. A compressor outlet temperature transmitter 4 is installed on the compressor outlet pipeline 3. A first drain pipeline 16 is installed at the bottom of the gas-liquid separator 5. A working fluid replenishment pipeline 502 is installed on the gas-liquid separator 5. A pH meter 601 is installed on the working fluid circulation pipeline 6.
[0036] This invention first treats the vinyl chloride waste gas emitted during the production process by removing acid and mist, ensuring that the pH is between 7.5 and 9.5 and the water content is ≤6%, thereby reducing or eliminating the risk of waste gas components agglomerating in the device.
[0037] The compressor head outlet temperature transmitter 4 monitors the temperature of the exhaust gas at the compressor head outlet of compressor 3. If the temperature exceeds the set temperature, the system will automatically alarm and shut down.
[0038] The buffer tank 1 is equipped with a pressure transmitter, which is interlocked with the frequency converter of the compressor 3. The compressor 3 can automatically adjust its operating frequency to match the air extraction volume with the air intake volume, thereby saving energy and stabilizing system operation.
[0039] This invention incorporates a buffer tank 1, which serves as a pressure buffer. Before the exhaust gas enters the compressor 3, the buffer tank 1 absorbs and releases pressure fluctuations, ensuring stable gas pressure entering the compressor 3 and preventing damage or efficiency reduction due to sudden pressure changes. The organic volatile gas generated downstream of the membrane separation system 11 mixes with the original exhaust gas in the buffer tank 1, which helps achieve a more uniform component distribution and reduces the problem of decreased treatment efficiency or equipment blockage caused by uneven component distribution.
[0040] pH meter 601 is used to monitor whether the pH of the working fluid circulating in the working fluid circulation pipeline 6 is maintained between 7.5 and 9.5. When the pH does not meet the set requirements, the pH of the working fluid in the gas-liquid separator 5 is adjusted.
[0041] Understandably, the compressor 3 is equipped with a head soft water pipeline 302 and a head temperature transmitter 301.
[0042] Understandably, the gas-liquid separator 5 is equipped with a first level transmitter 501, the first drain line 16 is equipped with a valve, the working fluid replenishment line 502 is equipped with a valve, and the output end of the first level transmitter 501 is electrically connected to the control end of the valve on the first drain line 16 and the valve on the working fluid replenishment line 502.
[0043] Filters are installed on the working fluid replenishment line 502 and the working fluid circulation line 6.
[0044] The liquid level inside the gas-liquid separator can be automatically controlled within a certain range. If the liquid level is too high, it will automatically drain from the bottom; if the liquid level is too low, it will automatically replenish the working fluid.
[0045] When the liquid level is too high, if liquid enters the gas pipeline, it can cause blockage, affecting the normal flow of gas. This not only reduces the system's processing efficiency but may also lead to safety accidents. Conversely, if the liquid level is too low, it may cause liquid entrainment in the gas. This not only reduces the purity of the gas but also damages downstream equipment, affecting its normal operation.
[0046] Changes in liquid level affect the pressure distribution inside the gas-liquid separator. Maintaining the liquid level within a certain range helps to stabilize the system pressure, thereby ensuring the normal operation of the entire system.
[0047] Understandably, the outlet of the gas-liquid separator 5 is equipped with a demister 503.
[0048] Understandably, the liquid collection tank 10 is equipped with a second liquid level transmitter 1001, the bottom of the liquid collection tank 10 is equipped with a second drain line 17, the second drain line 17 is equipped with a valve, and the output end of the second liquid level transmitter 1001 is electrically connected to the control end of the valve on the second drain line 17.
[0049] Similarly, when the liquid level in the collection tank 10 is too high, it will automatically drain from the bottom.
[0050] Understandably, the first drain line 16 and the second drain line 17 are connected to the solvent recovery device 18.
[0051] Understandably, the organic volatile gas transport pipeline 12 is equipped with a vacuum pump 15.
[0052] Working principle:
[0053] The vinyl chloride waste gas emitted during the production process is first treated with acid removal and demisting to ensure a pH of 7.5-9.5 and a water content of ≤6%. Then, it enters buffer tank 1 through a pipeline equipped with a flame arrester. The pressure transmitter installed on buffer tank 1 is interlocked with the frequency converter of compressor 3, allowing compressor 3 to automatically adjust its operating frequency to match the intake gas volume. Before starting compressor 3, soft water is used to replenish the working fluid at the compressor head via the soft water pipeline 302, and the fluid level is confirmed to be at the compressor head shaft. Subsequently, the valve on the soft water pipeline 302 is closed, and the valve on the working fluid replenishment pipeline 502 is opened to replenish the working fluid in the gas-liquid separator 5. The working fluid (soft water) is used. Once the first level sensor setpoint is reached, the valve is closed. The working fluid circulation pipeline 6, connected to the gas-liquid separator 5, is checked and confirmed to be full. The compressor 3 is then started. Exhaust gas and working fluid are ejected from the compressor 3 outlet into the gas-liquid separator 5. The heat exchanger 7 on the working fluid circulation pipeline 6 uses industrial circulating water as a cooling source. When the outlet gas temperature of the compressor 3 exceeds the set temperature, the system will automatically alarm or even shut down. Exhaust gas and working fluid enter the gas-liquid separator 5, where gas, water, and oil achieve three-phase self-separation. Chlorinated hydrocarbon liquid is at the bottom of the tank, water is in the middle layer, and the upper gas passes through the demister 503 at the top of the tank and enters the downstream condensing system. The liquid level in the gas-liquid separator is automatically controlled within a certain range. If the liquid level is too high, it will automatically drain from the bottom; if the liquid level is too low, it will automatically replenish the working fluid (water). After being discharged from the top of the gas-liquid separator 5, the gas enters the condensing system, which includes a precooler 8 and a condenser 9. The main purpose of the precooler 8 is to improve waste heat utilization efficiency and maximize energy savings. The non-condensable gas discharged from condenser 9 exchanges heat with the gas from the separator in precooler 8, increasing the temperature of the non-condensable gas entering the membrane and simultaneously lowering the temperature of the tail gas / waste liquid mixture entering condenser 9. The plate condenser 9 here uses refrigerant as the cold source, maintaining the non-condensable gas outlet temperature between 7-12℃. In condenser 9, the vapor partial pressure of organic gases will significantly exceed their corresponding saturated vapor partial pressure, causing liquefaction and entry into the collection tank 10. Similar to the gas-liquid separator 5, the liquid level in the collection tank is automatically controlled within a certain range; if the level is too high, liquid will be automatically drained from the bottom. The condensed gas enters the membrane separation system 11, whose main function is to enrich the small amount of volatile organic components contained in the non-condensable gas. Driven by the partial pressure difference of organic matter upstream and downstream of the membrane system, the rate at which volatile organic gases in the non-condensable gas permeate the membrane is significantly higher than that of air, allowing the organic matter to be enriched on the downstream side. It is then transported to buffer tank 1 via vacuum pump 15, and then coupled to the inlet of compressor 3 for further processing. The organic matter content in the exhaust gas that does not pass through the membrane is greatly reduced, and then it enters the oxygen pyrolysis system 14 for treatment to finally achieve emission standards.
[0054] The above description is merely an embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this utility model should be included within the scope of the claims of this utility model.
Claims
1. A membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas, characterized in that, The system includes a vinyl chloride waste gas feedstock pipeline (2), which is connected to a demister (20) via a deacidification tower (19). The demister (20) is connected to a buffer tank (1), which is connected to a gas-liquid separator (5) via a compressor (3). The gas-liquid separator (5) is connected to a condenser (9) via a precooler (8). The condenser (9) is connected to a collection tank (10), which is connected to the precooler (8) via a non-condensable gas pipeline (1002). The precooler (8) is connected to a membrane separation system (11), and the upstream of the membrane in the membrane separation system (11) is connected to a concentrated tail gas transport pipe. Line (13) is connected to the oxygen cracking system (14). Downstream of the membrane separation system (11) is connected to the buffer tank (1) via the organic volatile gas transport pipeline (12). The gas-liquid separator (5) is equipped with a working fluid circulation pipeline (6). A heat exchanger (7) is provided on the working fluid circulation pipeline (6). A compressor outlet temperature transmitter (4) is provided on the compressor outlet pipeline (3). A first drain pipeline (16) is provided at the bottom of the gas-liquid separator (5). A working fluid replenishment pipeline (502) is provided on the gas-liquid separator (5). A pH meter (601) is provided on the working fluid circulation pipeline (6).
2. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 1, characterized in that, The compressor (3) is equipped with a head soft water pipeline (302) and a head temperature transmitter (301).
3. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 1, characterized in that, The gas-liquid separator (5) is equipped with a first level transmitter (501), the first drain line (16) is equipped with a valve, the working fluid replenishment line (502) is equipped with a valve, and the output end of the first level transmitter (501) is electrically connected to the control end of the valve on the first drain line (16) and the valve on the working fluid replenishment line (502).
4. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 1, characterized in that, The outlet of the gas-liquid separator (5) is equipped with a demister (503).
5. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 1, characterized in that, The liquid collection tank (10) is equipped with a second liquid level transmitter (1001), and the bottom of the liquid collection tank (10) is equipped with a second drain line (17). The second drain line (17) is equipped with a valve, and the output end of the second liquid level transmitter (1001) is electrically connected to the control end of the valve on the second drain line (17).
6. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 5, characterized in that, The first drain line (16) and the second drain line (17) are connected to the solvent recovery device (18).
7. The membrane condensation and recovery device for 1,1-dichloroethylene organic waste gas according to claim 1, characterized in that, A vacuum pump (15) is installed on the organic volatile gas transport pipeline (12).