A high-pressure organic waste gas purification system

Abstract

This utility model belongs to the field of waste gas treatment technology, specifically disclosing a high-pressure organic waste gas purification system, including an absorption tower. A high-pressure waste gas pipeline is connected to the inlet of the absorption tower, and a suspension separator is connected to the outlet. A purifier is connected to the gas outlet of the suspension separator, and a solvent storage tank is connected to the liquid outlet of the suspension separator. The solvent storage tank is connected to the solvent inlet and outlet of the absorption tower, and a circulating pump and an absorbent cooler are connected in series on the pipeline connected to the inlet. Addressing the problem of environmental pollution caused by the direct emission of tail gas from the cyclohexanone oxidative distillation process, this utility model forms a waste gas purification system through the absorption tower, suspension separator, solvent storage tank, and absorbent cooler. This achieves efficient purification of the tail gas from the cyclohexanone oxidative distillation process and the recovery and utilization of the absorption solvent, solving the problem of environmental pollution caused by the direct emission of tail gas generated during the oxidative distillation stage of the cyclohexanone unit.

Description

Technical Field

[0001] This utility model relates to the field of waste gas treatment technology, specifically to a high-pressure organic waste gas purification system. Background Technology

[0002] Cyclohexanone, as an important organic chemical raw material, is widely used in the synthesis of caprolactam and adipic acid, as well as in coatings, solvents, and rubber additives. The core process for producing cyclohexanone currently involves the liquid-phase oxidation of cyclohexane to generate cyclohexyl hydrogen peroxide, followed by decomposition to obtain a mixture of cyclohexanone and cyclohexanol. Finally, high-purity cyclohexanone is obtained through multi-tower distillation separation and purification. During the oxidation reaction and distillation separation, process tail gases containing contaminants are inevitably generated: in the oxidation stage, due to the limited conversion rate of cyclohexane, the tail gas carries unreacted cyclohexane and trace amounts of oxidation byproducts; while in the distillation stage, components such as cyclohexanone and cyclohexanol, due to their low boiling points, partially volatilize in the overhead gas phase, forming tail gas together with non-condensable gases such as nitrogen and oxygen.

[0003] The tail gas produced by the oxidation and distillation units of the cyclohexanone plant contains volatile organic compounds (VOCs, such as cyclohexane, cyclohexanone, and cyclohexanol), CO, and NO. X And acidic substances (such as boric acid and adipic acid droplets). If these exhaust gases are emitted directly without treatment, they will cause serious environmental pollution. The volatile organic compounds in them will participate in photochemical reactions to form secondary pollutants such as ozone, which will harm the quality of the atmospheric environment. At the same time, some substances may be toxic, posing a potential threat to the ecosystem and human health. Therefore, it is particularly important to purify the exhaust gas from the cyclohexanone unit's oxidative distillation process.

[0004] In summary, to solve the above problems, it is necessary to provide a high-pressure organic waste gas purification system to address the environmental pollution caused by the direct emission of tail gas generated during the oxidative distillation process of the cyclohexanone unit. Utility Model Content

[0005] The purpose of this invention is to provide a high-pressure organic waste gas purification system to solve the problem of environmental pollution caused by the direct emission of tail gas generated in the oxidative distillation process of cyclohexanone devices.

[0006] To achieve the above objectives, the basic solution provided by this utility model is as follows: a high-pressure organic waste gas purification system, including an absorption tower, the absorption tower including a tower body, an air inlet and an exhaust outlet, the tower body being divided into a packing section and a plate section, a high-pressure waste gas pipeline connected to the air inlet, a suspension separator connected to the exhaust outlet, a purifier connected to the gas outlet of the suspension separator, a chimney connected to the gas outlet of the purifier, a solvent storage tank connected to the liquid outlet of the suspension separator, the solvent storage tank being connected to the solvent inlet at the top and the solvent outlet at the bottom of the absorption tower respectively, and a circulation pump and an absorbent cooler being provided on the pipeline connecting the solvent storage tank and the solvent inlet of the absorption tower.

[0007] The working principle of this utility model is as follows: When in use, high-pressure organic waste gas is first introduced into the absorption tower, so that the high-pressure waste gas comes into full contact with the absorption solvent in the absorption tower, thereby absorbing the organic pollutants in the high-pressure waste gas. Then, the absorbed waste gas is discharged from the exhaust port at the top of the absorption tower and enters the suspension separator, so that the small amount of solvent carried in the high-pressure waste gas is separated and returned to the solvent storage tank through the liquid outlet. The gas enters the purifier from the gas outlet, and the purified gas is discharged from the chimney.

[0008] The beneficial effects of this utility model are as follows: This utility model forms a circulating purification system through an absorption tower, a suspension separator, a solvent storage tank, and an absorbent cooler. While purifying the high-pressure waste gas, it also realizes the recycling of the solvent, reduces material consumption and operating costs, and thus solves the problem of environmental pollution caused by the direct emission of tail gas generated in the oxidative distillation stage of the cyclohexanone unit.

[0009] Option 2, which is a preferred option of the basic option, is equipped with electric heating tape on the solvent storage tank and the pipeline connecting the solvent storage tank and the absorption tower. By installing electric heating tape on the solvent storage tank and pipeline, the absorption solvent can be effectively prevented from freezing or becoming viscous, thereby ensuring that the purification system can operate stably in low-temperature environments and preventing system failure due to the solidification of the absorption solvent.

[0010] Option 3, a preferred option of the basic option, is that the solvent storage tank is equipped with a temperature sensor, which is electrically connected to a PLC controller. The switch of the electric heating tape is also electrically connected to the PLC controller. When the temperature of the absorbent liquid is lower than the set value of the temperature sensor, the electric heating tape can be turned on in time by the PLC controller, thereby ensuring the fluidity of the absorbent solvent and preventing the absorbent solvent from freezing.

[0011] Option 4, which is a preferred option of the basic option, is that the bottom of the absorption tower is equipped with a drain valve; the drain valve can periodically remove the polymer, impurities or high-viscosity waste liquid accumulated at the bottom of the tower, prevent blockage and scaling, and thus ensure the long-term stable operation of the system.

[0012] Option 5, a preferred embodiment of the basic option, describes an absorption tower comprising a tower body divided into a packing section and a plate section. The packing section is equipped with a liquid distributor, the top of the tower body has a demister, the middle of the tower body has a collection plate and a distribution plate, and the plate section has several layers of trays located below the distribution plate. This combination of packing and plate tower design improves the purification efficiency of waste gas. The liquid distributor ensures uniform distribution of the absorbent liquid, while the collection plate and distribution plate enable the redistribution and collection of liquid within the tower, preventing wall flow.

[0013] Option 6, which is a preferred option of the basic option, is provided with an overflow plate on the tray and a downcomer is staggered on one side of two adjacent trays. The downcomer can guide the liquid to flow downward in an orderly manner, and at the same time, it can also cause the air bubbles entrained in the liquid to rise and separate, thereby achieving gas-liquid separation and preventing gas from entering the next tray with the liquid, thus ensuring mass transfer efficiency.

[0014] Option 7, which is a preferred option of the basic option, is provided with a baffle at the bottom of the tower body, and the baffle is located above the solvent outlet of the absorption tower; the baffle can suppress the formation of eddies in the liquid at the bottom of the tower body, and prevent the generation of funnel-shaped eddies due to rotation when the liquid is discharged, thereby avoiding the gas being sucked into the drain pipe. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a high-pressure organic waste gas purification system according to this utility model;

[0016] Figure 2 This is a three-dimensional view of the absorption tower in a high-pressure organic waste gas purification system according to this utility model;

[0017] Figure 3 This is a three-dimensional sectional view of the absorption tower in a high-pressure organic waste gas purification system according to this utility model.

[0018] The reference numerals in the accompanying drawings of this instruction manual include: 1. Absorption tower; 2. Air inlet; 3. Exhaust outlet; 4. High-pressure waste gas pipeline; 5. Suspension separator; 6. Purifier; 7. Chimney; 8. Solvent storage tank; 9. Circulating pump; 10. Absorbent cooler; 11. Temperature sensor; 12. Drain valve; 13. Tower body; 14. Liquid distributor; 15. Demister; 16. Liquid collection plate; 17. Distribution plate; 18. Tower tray; 19. Overflow plate; 20. Downcomer; 21. Baffle. Detailed Implementation

[0019] The present invention will be further described in detail below through specific embodiments:

[0020] Example

[0021] like Figures 1 to 3As shown: A high-pressure organic waste gas purification system includes an absorption tower 1. A drain valve 12 is provided at the bottom of the absorption tower 1. The absorption tower 1 includes a tower body 13, with an inlet 2 and an outlet 3. The tower body 13 is divided into a packing section and a plate section. A liquid distributor 14 is provided in the packing section of the tower body 13. A demister 15 is provided at the top of the tower body 13. A liquid collecting plate 16 and a distribution plate 17 are provided in the middle of the tower body 13. The plate section of the tower body 13 has several layers of trays 18, with the trays 18 located below the distribution plates 17. An overflow plate 19 is provided on the trays 18. Downcomers 20 are staggered on one side of adjacent trays 18. A baffle 21 is provided at the bottom of the tower body 13, located above the solvent outlet of the absorption tower 1. The inlet 2 is connected to... A high-pressure exhaust gas pipeline 4 is connected to the exhaust port 3, and a suspension separator 5 is connected to the exhaust port 3. A purifier 6 is connected to the gas outlet of the suspension separator 5, and a chimney 7 is connected to the gas outlet of the purifier 6. A solvent storage tank 8 is connected to the liquid outlet of the suspension separator 5. The solvent storage tank 8 is connected to the solvent inlet at the top and the solvent outlet at the bottom of the absorption tower 1. A circulation pump 9 and an absorbent cooler 10 are installed on the pipeline connecting the solvent storage tank 8 to the solvent inlet of the absorption tower 1. Electric heating tapes are installed on both the solvent storage tank 8 and the pipeline connecting the solvent storage tank 8 to the absorption tower 1. A temperature sensor 11 is installed on the solvent storage tank 8. A PLC controller is electrically connected to the temperature sensor 11. The switch of the electric heating tape is electrically connected to the PLC controller.

[0022] The implementation method of this embodiment is as follows: When it is necessary to purify the tail gas of cyclohexanone oxidative distillation, the tail gas of cyclohexanone oxidative distillation is first introduced into the absorption tower 1 through the inlet 2. The absorption solvent in the solvent storage tank 8 is cooled by the circulating pump 9 and then enters the tower body 13 through the solvent inlet and is evenly distributed in the packing section by the distributor 14. Then it flows into the tower plate 18 through the collecting plate 16 and the distribution plate 17. During the rising process, the tail gas of cyclohexanone oxidative distillation first comes into contact with the absorption solvent on the tower plate 18 through the plate section, and then comes into contact with the absorption solvent in the packing section. The solvent is in full contact with the gas, allowing the organic pollutants in the cyclohexanone oxidative distillation tail gas to be absorbed. After the organic pollutants are absorbed, the cyclohexanone oxidative distillation tail gas is discharged from the exhaust port 3 at the top of the absorption tower 1 and enters the suspension separator 5. In the suspension separator 5, a small amount of solvent carried by the cyclohexanone oxidative distillation tail gas is separated and returned to the solvent storage tank 8 through the liquid outlet. The gas enters the purifier 6 from the gas outlet, where the VOCs in the cyclohexanone oxidative distillation tail gas are adsorbed by the molecular sieve inside the purifier 6. Finally, the purified gas is discharged from the chimney 7.

[0023] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A high-pressure organic waste gas purification system, characterized in that, The absorption tower (1) includes a tower body (13), which is provided with an air inlet (2) and an exhaust outlet (3). The tower body (13) is divided into a packing section and a plate section. A high-pressure waste gas pipeline (4) is connected to the air inlet (2). A suspension separator (5) is connected to the exhaust outlet (3). A purifier (6) is connected to the gas outlet of the suspension separator (5). A chimney (7) is connected to the gas outlet of the purifier (6). A solvent storage tank (8) is connected to the liquid outlet of the suspension separator (5). The solvent storage tank (8) is connected to the solvent inlet at the top and the solvent outlet at the bottom of the absorption tower (1). A circulation pump (9) and an absorbent cooler (10) are provided on the pipeline connecting the solvent storage tank (8) and the solvent inlet of the absorption tower (1).

2. The high-pressure organic waste gas purification system according to claim 1, characterized in that, Electric heating tapes are installed on the solvent storage tank (8) and the pipeline connecting the solvent storage tank (8) to the absorption tower (1).

3. A high pressure organic exhaust gas purification system according to claim 2, characterized in that The solvent storage tank (8) is equipped with a temperature sensor (11), and a PLC controller is electrically connected to the temperature sensor (11). The switch of the electric heating tape is electrically connected to the PLC controller.

4. The high-pressure organic waste gas purification system according to claim 1, characterized in that, The bottom of the absorption tower (1) is equipped with a drain valve (12).

5. The high pressure lean NOx trap system of claim 1, wherein, The tower body (13) has a liquid distributor (14) in the packing section, a demister (15) at the top of the tower body (13), a liquid collection plate (16) and a distribution plate (17) in the middle of the tower body (13), and a number of trays (18) in the plate section of the tower body (13), with the trays (18) located below the distribution plate (17).

6. A high pressure lean NOx trap system according to claim 5, wherein The tray (18) is provided with an overflow plate (19), and the sides of two adjacent trays (18) are alternately provided with downcomers (20).

7. A high pressure lean NOx trap system according to claim 5, wherein The bottom of the tower body (13) is provided with a baffle (21), which is located above the solvent outlet of the absorption tower (1).

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