PAN-based carbon fiber polymerization tail gas treatment device
By designing a PAN-based carbon fiber polymer exhaust gas treatment device, using multi-stage absorption and adsorption to treat exhaust gas, the problem of frequent replacement of activated carbon is solved, the recycling of acrylonitrile and dimethyl sulfoxide is achieved, and production costs and environmental pollution are reduced.
Patent Information
- Application Number
- CN202422312994.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-08-19
- Estimated Expiration
- 2034-09-23
AI Technical Summary
In traditional exhaust gas treatment methods, activated carbon adsorption treatment needs to be replaced regularly, resulting in the inability to recover dimethyl sulfoxide and acrylonitrile, which increases production costs and causes environmental pollution.
A PAN-based carbon fiber polymer exhaust gas treatment device is designed, including an acrylonitrile absorption mechanism, an acrylonitrile recovery tank, a dimethyl sulfoxide absorption mechanism, a dimethyl sulfoxide recovery tank, a dehydration mechanism, an adsorption mechanism and a exhaust gas emission mechanism. Through multi-stage absorption and adsorption treatment of exhaust gas, the recovery of acrylonitrile and dimethyl sulfoxide is realized.
It extends the replacement cycle of activated carbon, reduces energy consumption, reduces environmental pollution and production costs, and realizes the recycling of harmful components in exhaust gas.
Smart Images
Figure CN223233577U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of carbon fiber production and manufacturing, and specifically to a PAN-based carbon fiber polymerization tail gas treatment device with a reasonable structure and low energy consumption, which can reduce the cost of tail gas recovery and treatment in the carbon fiber production and manufacturing process and can realize the recovery of acrylonitrile and dimethyl sulfoxide in the tail gas. Background Art
[0002] The polymerization process in PAN-based carbon fiber production generates tail gas, primarily composed of nitrogen, dimethyl sulfoxide (DMSO), acrylonitrile, and water. This tail gas must be treated before discharge to reduce environmental pollution. Traditionally, activated carbon adsorption is used for tail gas treatment. This activated carbon, which contains dimethyl sulfoxide and acrylonitrile, requires regular replacement. This replaced activated carbon contains dimethyl sulfoxide and acrylonitrile, requiring disposal as hazardous waste and non-recyclable, significantly increasing production costs. Summary of the Invention
[0003] The utility model aims to solve the problem of tail gas treatment in the current PAN-based carbon fiber polymerization process, and proposes a PAN-based carbon fiber polymerization tail gas treatment device with a reasonable structure, low energy consumption, and the ability to reduce the tail gas recovery and treatment costs in the carbon fiber production process and to recover acrylonitrile and dimethyl sulfoxide in the tail gas.
[0004] The utility model is achieved through the following measures:
[0005] A PAN-based carbon fiber polymerization tail gas treatment device, characterized in that it is provided with an acrylonitrile absorption mechanism, an acrylonitrile recovery tank, a dimethyl sulfoxide absorption mechanism, a dimethyl sulfoxide recovery tank, a dehydration mechanism, an adsorption mechanism and a tail gas discharge mechanism, wherein the air outlet of the acrylonitrile absorption mechanism is connected to the air inlet of the dimethyl sulfoxide absorption mechanism, the air outlet of the dimethyl sulfoxide absorption mechanism is connected to the air inlet of the dehydration mechanism, the air outlet of the dehydration mechanism is connected to the air inlet of the adsorption mechanism, the air outlet of the adsorption mechanism is connected to the air inlet of the tail gas discharge mechanism, the acrylonitrile recovery tank is connected to the acrylonitrile absorption mechanism, the dimethyl sulfoxide recovery tank is connected to the dimethyl sulfoxide absorption mechanism, and the air outlet of the adsorption mechanism is connected to the air inlet of the tail gas discharge mechanism. The acrylonitrile absorption tower is connected to a methyl sulfoxide recovery mechanism, and the acrylonitrile recovery mechanism is provided with an acrylonitrile absorption tower. The upper end of the acrylonitrile absorption tower is connected to a dimethyl sulfoxide feeding assembly, and the lower end of the acrylonitrile absorption tower is connected to an acrylonitrile recovery tank. A tail gas input interface is provided at the lower part of the side of the acrylonitrile absorption tower, and a gas discharge port is provided at the upper part of the side of the acrylonitrile absorption tower opposite to the tail gas input interface. The dimethyl sulfoxide feeding assembly includes a dimethyl sulfoxide delivery pipeline connected to the upper end of the acrylonitrile absorption tower, a spray head extending into the acrylonitrile absorption tower is provided at the end of the dimethyl sulfoxide delivery pipeline, and a heat exchanger, a temperature sensor and a flow meter are provided at the front end of the dimethyl sulfoxide delivery pipeline.
[0006] The dimethyl sulfoxide absorption mechanism of the present invention is provided with a dimethyl sulfoxide absorption tower, the upper end of the dimethyl sulfoxide absorption tower is connected to a water delivery assembly, the water delivery assembly includes a delivery pipe connected to the upper end of the dimethyl sulfoxide absorption tower, the end of the delivery pipe is connected to a spray head, the spray head is placed in the dimethyl sulfoxide absorption tower, the front end of the delivery pipe is connected to a heat exchanger, the delivery pipe is also provided with a temperature sensor and a flow meter, a packing layer is provided in the dimethyl sulfoxide absorption tower, a packing ring is provided in the packing layer to increase the contact area between the tail gas and the packing, the lower end of the dimethyl sulfoxide absorption tower is connected to a dimethyl sulfoxide recovery tank, an air inlet is provided at the lower part of one side of the dimethyl sulfoxide absorption tower, and an air outlet is provided at the upper part of the opposite side; further, three spray heads arranged at equal intervals are provided in the water delivery assembly, each spray head adopts a rotating spray head, and the extension length of the spray head located in the center is greater than the extension length of the spray heads on both sides.
[0007] The utility model is provided with a multi-stage acrylonitrile absorption mechanism, which is sequentially connected in series and is all connected to an acrylonitrile recovery tank. Preferably, a three-stage acrylonitrile absorption mechanism is provided. Furthermore, a dimethyl sulfoxide feeding assembly connected to the upper end of an acrylonitrile absorption tower in the acrylonitrile absorption mechanism is provided with three rotary spray heads, which all extend into the acrylonitrile absorption tower. The three rotary spray heads are evenly spaced, and the length of the rotary spray head located in the middle is greater than the extension length of the rotary spray heads on both sides. Furthermore, a packing layer is provided in the acrylonitrile absorption tower, and a packing ring is installed in the packing layer to expand the contact area between the tail gas and the dimethyl sulfoxide.
[0008] The dehydration mechanism of the utility model adopts a refrigeration dryer for drying, which is used to cool the exhaust gas to a certain dew point, so that the oversaturated water is analyzed out, and the liquid water is separated by a steam-water separator; the adsorption mechanism adopts activated carbon for adsorption treatment; the exhaust gas discharge mechanism is provided with an exhaust gas buffer tank, and the clean exhaust gas is discharged after being buffered in the exhaust gas buffer tank.
[0009] When the utility model is in operation, tail gas containing acrylonitrile and dimethyl sulfoxide is fed into the acrylonitrile absorption mechanism, fully mixed with the dimethyl sulfoxide fed into the acrylonitrile absorption mechanism, and acrylonitrile in the tail gas containing acrylonitrile and dimethyl sulfoxide is absorbed to form an acrylonitrile-dimethyl sulfoxide mixed liquid which is sent to an acrylonitrile recovery tank; the tail gas leaves the acrylonitrile absorption mechanism and goes to the dimethyl sulfoxide absorption mechanism to recover dimethyl sulfoxide, the formed dimethyl sulfoxide-water mixed liquid is sent to the dimethyl sulfoxide recovery tank for treatment, the sent tail gas goes to the dehydration mechanism for dehydration treatment, the dehydrated tail gas goes to the adsorption mechanism for adsorption treatment, and the treated clean tail gas enters the tail gas discharge mechanism for discharge.
[0010] Compared with the prior art, the utility model processes polymerization tail gas through an acrylonitrile absorption mechanism, an acrylonitrile recovery tank, a dimethyl sulfoxide absorption mechanism, a dimethyl sulfoxide recovery tank, a dehydration mechanism, an adsorption mechanism, etc., thereby realizing the recovery of dimethyl sulfoxide and acrylonitrile in the tail gas, extending the replacement cycle of activated carbon, reducing environmental pollution, lowering energy consumption, and reducing waste. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Attachment Figure 1 It is a structural diagram of the utility model.
[0012] Attachment Figure 2 It is a structural schematic diagram of the acrylonitrile recovery mechanism in the utility model.
[0013] Attachment Figure 3 It is a structural schematic diagram of the dimethyl sulfoxide recovery mechanism in the utility model.
[0014] Figure 1: A. Acrylonitrile absorption mechanism 1, B. Acrylonitrile absorption mechanism 2, C. Acrylonitrile absorption mechanism 3, D. Acrylonitrile recovery tank, E. Dimethyl sulfoxide absorption mechanism, F. Dimethyl sulfoxide recovery tank, G. Dehydration mechanism, H. Adsorption mechanism, I. Tail gas emission mechanism, J. Dimethyl sulfoxide heat exchanger, K. Mass flow meter, L. Acrylonitrile absorption tower, D. Acrylonitrile recovery tank, M. Packing layer of Acrylonitrile absorption tower, N. Rotating spray head in Acrylonitrile absorption tower, O. Temperature sensor in Acrylonitrile absorption mechanism, P. Heat exchanger, Q. Mass flow meter, R. Dimethyl sulfoxide absorption tower, F. Dimethyl sulfoxide recovery tank, S. Packing layer of Acrylonitrile absorption tower, T. Rotating spray head in Dimethyl sulfoxide absorption tower, U. Temperature sensor, 1. Primary dimethyl sulfoxide, 2. Secondary dimethyl sulfoxide, 3. Tertiary dimethyl sulfoxide, 4. Tail gas containing acrylonitrile and dimethyl sulfoxide, 5. Acrylonitrile-dimethyl sulfoxide mixture, 6. First tail gas, 7. Acrylonitrile-dimethyl sulfoxide mixture, 8. Second tail gas, 9. Acrylonitrile-dimethyl sulfoxide mixture, 10. Third tail gas, 11. Fourth tail gas, 12. Dimethyl sulfoxide-water mixture, 13. Fifth tail gas, 14. Clean tail gas, 15. Dimethyl sulfoxide, 16. Acrylonitrile-dimethyl sulfoxide mixture, 17. Heat exchanger circulating water inlet, 18. Heat exchanger circulating water return, 19. Process water, 20. Heat exchanger circulating water inlet, 21. Heat exchanger circulating water return. DETAILED DESCRIPTION
[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0016] Example 1:
[0017] This example proposes a Figure 1 As shown, a PAN-based carbon fiber polymerization tail gas treatment device with a three-stage acrylonitrile absorption mechanism is shown. In this example, the acrylonitrile absorption mechanism consists of a dimethyl sulfoxide (DMSO) heat exchanger, a mass flowmeter, and an acrylonitrile absorption tower. A temperature sensor O is located at the outlet of the DMSO heat exchanger J. DMSO 15 is controlled in temperature by the DMSO heat exchanger J and in flow by the mass flowmeter K before entering the acrylonitrile absorption tower L. The acrylonitrile-DMSO mixture 16 is discharged into an acrylonitrile recovery tank D. Within the acrylonitrile absorption tower L are three rotating spray heads N, mounted vertically and equidistantly within the tower. The center rotating spray head extends deeper into the equipment than the other two. The acrylonitrile absorption tower contains a packing layer M, which is equipped with packing rings to maximize the contact area between the exhaust gas and DMSO. The exhaust gas containing acrylonitrile and DMSO enters the lower end of the acrylonitrile absorption tower and is discharged through the exhaust outlet. The dimethyl sulfoxide heat exchanger J is connected to a circulating water inlet 17 and a circulating water return 19. The temperature of the dimethyl sulfoxide is adjusted by the circulating water of the dimethyl sulfoxide heat exchanger J.
[0018] The DMSO absorption mechanism consists of a heat exchanger, a mass flowmeter, and a DMSO absorption tower. A temperature sensor U is located at the outlet of heat exchanger P. Process water 19 flows through heat exchanger P for temperature control and mass flowmeter Q for flow control before entering DMSO absorption tower R. The DMSO-water mixture 12 is discharged into a DMSO recovery tank F. Inside DMSO absorption tower R, there are three rotating spray heads T. These are vertically mounted within the tower, spaced evenly apart, with the center head extending deeper into the equipment than the other two. The DMSO absorption tower contains a packing layer S, which is equipped with packing rings to increase the contact area between the tertiary off-gas 10 and the water. The tertiary off-gas 10 enters the DMSO absorption tower from the bottom, and the water-containing off-gas 11 is discharged from the top. Circulating water inlet 20 and return 21 flow through heat exchanger P. The temperature of the process water is adjusted by the circulating water from heat exchanger P.
[0019] For the tail gas 4 containing acrylonitrile and dimethyl sulfoxide, the acrylonitrile concentration is less than 2000 mg / m³, the dimethyl sulfoxide concentration is less than 600 mg / m³, and the tail gas flow rate is 30 m³ / h-35 m³ / h. After the treatment in this example, the dimethyl sulfoxide concentration in the clean tail gas is less than 0.2 mg / m³, and the acrylonitrile concentration is less than 0.2 mg / m³.
[0020] Compared with the prior art, the utility model processes polymerization tail gas through an acrylonitrile absorption mechanism, an acrylonitrile recovery tank, a dimethyl sulfoxide absorption mechanism, a dimethyl sulfoxide recovery tank, a dehydration mechanism, an adsorption mechanism, etc., thereby realizing the recovery of dimethyl sulfoxide and acrylonitrile in the tail gas, extending the replacement cycle of activated carbon, reducing environmental pollution, lowering energy consumption, and reducing waste.
Claims
1. A PAN-based carbon fiber polymerization tail gas treatment device, characterized in that: An acrylonitrile absorption mechanism, an acrylonitrile recovery tank, a dimethyl sulfoxide absorption mechanism, a dimethyl sulfoxide recovery tank, a dehydration mechanism, an adsorption mechanism and a tail gas discharge mechanism are provided, wherein the air outlet of the acrylonitrile absorption mechanism is connected to the air inlet of the dimethyl sulfoxide absorption mechanism, the air outlet of the dimethyl sulfoxide absorption mechanism is connected to the air inlet of the dehydration mechanism, the air outlet of the dehydration mechanism is connected to the air inlet of the adsorption mechanism, the air outlet of the adsorption mechanism is connected to the air inlet of the tail gas discharge mechanism, the acrylonitrile recovery tank is connected to the acrylonitrile absorption mechanism, the dimethyl sulfoxide recovery tank is connected to the dimethyl sulfoxide recovery mechanism, and the The acrylonitrile recovery mechanism is provided with an acrylonitrile absorption tower, the upper end of the acrylonitrile absorption tower is connected to a dimethyl sulfoxide feeding assembly, the lower end of the acrylonitrile absorption tower is connected to an acrylonitrile recovery tank, a tail gas input interface is provided at the lower side of the acrylonitrile absorption tower, and a gas discharge outlet is provided at the upper side of the acrylonitrile absorption tower opposite to the tail gas input interface. The dimethyl sulfoxide feeding assembly includes a dimethyl sulfoxide delivery pipeline connected to the upper end of the acrylonitrile absorption tower, a spray head extending into the acrylonitrile absorption tower is provided at the end of the dimethyl sulfoxide delivery pipeline, and a heat exchanger, a temperature sensor and a flow meter are provided at the front end of the dimethyl sulfoxide delivery pipeline.
2. The PAN-based carbon fiber polymerization tail gas treatment device according to claim 1, characterized in that: The dimethyl sulfoxide absorption mechanism is provided with a dimethyl sulfoxide absorption tower, the upper end of the dimethyl sulfoxide absorption tower is connected to a water delivery assembly, the water delivery assembly includes a delivery pipe connected to the upper end of the dimethyl sulfoxide absorption tower, the end of the delivery pipe is connected to a spray head, the spray head is placed in the dimethyl sulfoxide absorption tower, the front end of the delivery pipe is connected to a heat exchanger, the delivery pipe is also provided with a temperature sensor and a flow meter, the dimethyl sulfoxide absorption tower is provided with a packing layer, and a packing ring is provided in the packing layer to increase the contact area between the tail gas and the packing, the lower end of the dimethyl sulfoxide absorption tower is connected to a dimethyl sulfoxide recovery tank, an air inlet is provided at the lower part of one side of the dimethyl sulfoxide absorption tower, and an air outlet is provided at the upper part of the opposite side; the water delivery assembly is provided with three spray heads arranged at equal intervals, each spray head adopts a rotating spray head, and the extension length of the spray head located in the center is greater than the extension length of the spray heads on both sides.
3. The PAN-based carbon fiber polymerization tail gas treatment device according to claim 1, characterized in that: A three-stage acrylonitrile absorption mechanism is provided, which is connected in series and connected to an acrylonitrile recovery tank. The dimethyl sulfoxide feeding assembly connected to the upper end of the acrylonitrile absorption tower in the acrylonitrile absorption mechanism is provided with three rotary spray heads, which all extend into the acrylonitrile absorption tower. The three rotary spray heads are evenly spaced, and the length of the rotary spray head in the middle is greater than the extension length of the rotary spray heads on both sides. A packing layer is provided in the acrylonitrile absorption tower, and a packing ring is installed in the packing layer to expand the contact area between the tail gas and the dimethyl sulfoxide.
4. The PAN-based carbon fiber polymerization tail gas treatment device according to claim 1, characterized in that: The dehydration mechanism adopts a refrigeration dryer for drying, and the adsorption mechanism adopts activated carbon for adsorption treatment; the tail gas emission mechanism is provided with a tail gas buffer tank, and the clean tail gas is discharged after being buffered in the tail gas buffer tank.