Energy-saving recovery system for intermittent high-vapor-pressure organic solvent exhaust gas
Patent Information
- Application Number
- CN202522113438.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-30
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-09-30
AI Technical Summary
[0002]在工业生产或其他过程中往往会间歇性的产生流量较小的废气，这类废气中含有高饱和蒸汽压(≥30kPa@25℃)、小废气量(≤1000m3/h)的有机溶剂(如丙酮、乙醚、二氯甲烷等)，传统的处理方式是采用制冷机组进行冷凝回收，但是由于该类废气为间歇性排放，这样就导致处理系统需要频繁地启停，而频繁启停会严重损坏装置的使用寿命，大大增加了工业处理成本
[0013](1)本实用新型通过将吸附罐与风机连通，在没有废气排出时，通过阀门控制，将吸附罐内回收的废气引入风机，使得后续的装置均可以连续工作，无需频繁启停，不仅保证了循环系统达标排放，而且延长了设备的使用寿命
Smart Images
Figure CN224822078U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of volatile organic compound (VOCs) resource recovery technology, and particularly relates to an energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas. Background Technology
[0002] Industrial production or other processes often generate intermittently small-flow-rate waste gases. These waste gases contain high saturated vapor pressure (≥30kPa@25℃) and small waste gas volume (≤1000m³). 3 For organic solvents (such as acetone, diethyl ether, dichloromethane, etc.) emitted per hour, the traditional treatment method is to use a refrigeration unit for condensation and recovery. However, since this type of waste gas is emitted intermittently, the treatment system needs to be started and stopped frequently. Frequent start-ups and shutdowns will seriously damage the service life of the equipment and greatly increase the industrial treatment cost. Utility Model Content
[0003] To overcome the shortcomings of the existing technology, this invention provides an energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas. This invention introduces the waste gas from the adsorption tank into a fan, ensuring that the circulation system meets emission standards and avoiding frequent start-ups and shutdowns of the fan and secondary cryogenic unit.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] An energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas includes a buffer tank, a fan, a secondary cryogenic unit, a reheating device, an adsorption tank, and an exhaust pipe connected in sequence; the outlet of the adsorption tank is also connected to the inlet of the fan through a valve, the secondary cryogenic unit is used to condense the organic solvent in the organic waste gas, and the inlet of the buffer tank is connected to the intermittent exhaust gas discharge pipe.
[0006] Preferably, the two-stage cryogenic unit includes a first heat exchanger for primary cooling of organic waste gas and a cryogenic unit for secondary cooling of organic waste gas. The heat medium inlet of the first heat exchanger is connected to the air outlet of the fan, the heat medium outlet of the first heat exchanger is connected to the waste gas inlet of the cryogenic unit, the non-condensable gas outlet of the cryogenic unit is connected to the cold source inlet of the first heat exchanger, and the cold source outlet of the first heat exchanger is connected to the reheating device.
[0007] Preferably, the reheating device is a second heat exchanger, the cold source inlet of the second heat exchanger is connected to the cold source outlet of the first heat exchanger, the cold source outlet of the second heat exchanger is connected to the air inlet of the adsorption tank, and the heat medium of the second heat exchanger is cold water at 5°C.
[0008] Preferably, the air outlet of the buffer tank is connected to the air inlet of the filter, and the air outlet of the filter is connected to the air inlet of the blower.
[0009] Preferably, the cooling medium of the cryogenic device is one of liquid nitrogen, R404A, and R508B.
[0010] Preferably, the emission pipe is equipped with an online monitoring instrument for monitoring the concentration of exhaust gas.
[0011] Preferably, the adsorption layer of the adsorption tank is one of activated carbon, molecular sieve, or resin.
[0012] The advantages of this utility model are:
[0013] (1) By connecting the adsorption tank to the fan, this utility model allows the recovered waste gas in the adsorption tank to be introduced into the fan through valve control when there is no waste gas discharge, so that the subsequent devices can work continuously without frequent start-stop, which not only ensures that the circulation system meets the emission standards, but also extends the service life of the equipment.
[0014] (2) The two-stage cryogenic unit of this utility model cools the exhaust gas step by step and uses the exhaust gas cooled in the cryogenic unit as the cold source of the first heat exchanger, so that the exhaust gas is reused, which not only improves the cooling efficiency but also reduces energy consumption.
[0015] (3) The second heat exchanger in this utility model heats up the cold exhaust gas (-20℃ to -30℃) discharged from the first heat exchanger by using cold water at 7-12℃, which greatly improves the adsorption efficiency of the subsequent adsorption tank; the filter can filter dust and other particles in the exhaust gas, thus avoiding affecting the service life of the subsequent equipment. Attached Figure Description
[0016] Figure 1 This is a process diagram of the present utility model.
[0017] The meanings of the symbols marked in the figure are as follows:
[0018] 1-Exhaust gas discharge pipe, 2-Buffer tank, 3-Filter, 4-Fan, 5-Secondary cryogenic unit, 6-First heat exchanger, 7-Cryogenic unit, 8-Second heat exchanger, 9-Adsorption tank, 10-Discharge pipe. Detailed Implementation
[0019] like Figure 1 As shown, an energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas includes a buffer tank 2, a fan 4, a secondary cryogenic unit 5, a reheating device, an adsorption tank 9, and an exhaust pipe 10 connected in sequence. The outlet of the adsorption tank 9 is also connected to the inlet of the fan 4 through a pressure valve. The secondary cryogenic unit 5 is used to condense the organic solvent in the organic waste gas. The inlet of the buffer tank 2 is connected to the intermittent exhaust pipe 1. When the pressure valve detects that the pressure in the inlet section of the fan 4 is insufficient, it opens, so that the waste gas in the adsorption tank 9 is connected to the fan 4, ensuring the normal operation of the fan 4 and other downstream equipment and avoiding frequent start-stop.
[0020] Specifically, the secondary cryogenic unit 5 includes a first heat exchanger 6 for primary cooling of organic waste gas and a cryogenic unit 7 for secondary cooling of organic waste gas. The heat medium inlet of the first heat exchanger 6 is connected to the outlet of the fan 4, the heat medium outlet of the first heat exchanger 6 is connected to the waste gas inlet of the cryogenic unit 7, the non-condensable gas outlet of the cryogenic unit 7 is connected to the cold source inlet of the first heat exchanger 6, and the cold source outlet of the first heat exchanger 6 is connected to the reheating device. The cryogenic unit 7 recovers organic solvents from the waste gas.
[0021] Furthermore, the reheating device is a second heat exchanger 8. The cold source inlet of the second heat exchanger 8 is connected to the cold source outlet of the first heat exchanger 6, and the cold source outlet of the second heat exchanger 8 is connected to the air inlet of the adsorption tank 9. The heat medium of the second heat exchanger 8 is cold water at 7-12℃. The reheating device can heat up the cold waste gas (-20℃ to -30℃) discharged from the first heat exchanger 6, thereby improving the adsorption efficiency of the adsorption tank 9. The air outlet of the buffer tank 2 is connected to the air inlet of the filter 3, and the air outlet of the filter 3 is connected to the air inlet of the fan 4. The cold medium of the cryogenic cooler 7 is liquid nitrogen, R404A, or R508B. An online monitoring instrument for monitoring the waste gas concentration is installed on the discharge pipe 10.
[0022] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas, characterized in that: It includes a buffer tank (2), a fan (4), a secondary cryogenic unit (5), a reheating device, an adsorption tank (9), and an exhaust pipe (10) connected in sequence; the outlet of the adsorption tank (9) is also connected to the inlet of the fan (4) through a valve; the secondary cryogenic unit (5) is used to condense the organic solvent in the organic waste gas; and the inlet of the buffer tank (2) is connected to the intermittent exhaust pipe (1).
2. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 1, characterized in that: The secondary cryogenic unit (5) includes a first heat exchanger (6) for primary cooling of organic waste gas and a cryogenic unit (7) for secondary cooling of organic waste gas. The heat medium inlet of the first heat exchanger (6) is connected to the outlet of the fan (4), the heat medium outlet of the first heat exchanger (6) is connected to the waste gas inlet of the cryogenic unit (7), the non-condensable gas outlet of the cryogenic unit (7) is connected to the cold source inlet of the first heat exchanger (6), and the cold source outlet of the first heat exchanger (6) is connected to the reheating device.
3. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 1, characterized in that: The reheating device is a second heat exchanger (8). The cold source inlet of the second heat exchanger (8) is connected to the cold source outlet of the first heat exchanger (6). The cold source outlet of the second heat exchanger (8) is connected to the air inlet of the adsorption tank (9). The heat medium of the second heat exchanger (8) is cold water at 7-12℃.
4. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 1, characterized in that: The air outlet of the buffer tank (2) is connected to the air inlet of the filter (3), and the air outlet of the filter (3) is connected to the air inlet of the fan (4).
5. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 2, characterized in that: The cooling medium of the cryogenic device (7) is one of liquid nitrogen, R404A, or R508B.
6. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 1, characterized in that: The discharge pipe (10) is equipped with an online monitoring instrument for monitoring the concentration of exhaust gas.
7. The energy-saving recovery system for intermittent high vapor pressure organic solvent waste gas according to claim 1, characterized in that: The adsorption layer of the adsorption tank (9) is one of activated carbon, molecular sieve, or resin.