Molecular sieve dehydration regeneration device for solvent recovery
By using nitrogen heating and cooling technology in the molecular sieve dehydration and regeneration device, the drying, heating and cooling process of the molecular sieve is independently completed, which solves the problem of low dehydration capacity in traditional processes, improves efficiency and reduces costs, and achieves efficient solvent recovery and environmentally friendly and pollution-free treatment effects.
Patent Information
- Application Number
- CN202421932687.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-09
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-08-09
AI Technical Summary
The traditional molecular sieve dehydration process results in the dehydration capacity being lower than the design processing capacity, and the equipment layout takes up a large space and high investment and installation costs.
The drying, heating and cooling process of the molecular sieve is independently completed by nitrogen heating and cooling. It is independent of the operation stage of the desorption device, which improves the efficiency of dehydration and regeneration, and separates the removed solvent and wastewater in the phase separation tank through density difference to control the water content in the gravy solvent.
The efficiency of the molecular sieve dehydration and regeneration device is improved, the space occupation and cost of equipment layout is reduced, and the efficient recycling of solvents is ensured, environmentally friendly and pollution-free.
Smart Images
Figure CN222900285U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of waste gas treatment equipment and relates to a molecular sieve dehydration and regeneration device for solvent recovery. Background Technique
[0002] Organic waste gas pollution has a wide range of sources and involves many industries; moreover, it has characteristics such as being flammable, explosive, toxic, and harmful, and being difficult to treat. At present, for the characteristics of organic waste gas, the mainstream treatment processes are regenerative thermal oxidation waste gas treatment technology (RTO) and solvent recovery technology. The principle of the regenerative thermal oxidation waste gas treatment technology is to burn organic waste gas under high-temperature conditions to generate carbon dioxide and water; a ceramic regenerative heat storage bed is used to recover the heat after incineration to achieve the effects of treatment and energy conservation. The solvent recovery technology is to recover and utilize the organic solvents in the organic waste gas through processes such as adsorption - desorption - dehydration - rectification, etc., to achieve the purpose of purification treatment. Compared with the traditional RTO treatment, the solvent recovery technology is not only energy-saving but also can recover a large amount of solvents. On the premise of meeting the treatment requirements and environmental protection, it can save a large amount of raw materials for customers and has been increasingly recognized by the market in recent years.
[0003] In the traditional molecular sieve dehydration process, the residual solvents and water in the molecular sieve are condensed and recovered through the equipment of the desorption device. Now, in more and more customer sites, the dehydration and rectification equipment is in the Class A fire hazard area, which is far from the area where the pretreatment adsorption and desorption equipment is located. In the traditional process design, there are several air ducts with a diameter of DN300 or above between dehydration and adsorption and desorption, which occupy a large amount of pipe gallery space. Due to the long distance, the investment and installation costs of pipelines and pipe galleries are high. In addition, the solvent dried by the molecular sieve can only be carried out in the desorption and condensation stage, and the waiting time is relatively long, resulting in the dehydration capacity being lower than the designed processing capacity of the molecular sieve. The utility model uses nitrogen heating and cooling to complete the drying, heating, and cooling processes of the molecular sieve, which has nothing to do with the operation stage of the desorption device and improves the efficiency of dehydration and regeneration. The removed solvents and waste water can be separated in the phase separation tank through the density difference, effectively controlling the water content in the crude solvent. Content of the Utility Model
[0004] The purpose of the utility model is to provide a molecular sieve dehydration and regeneration device for solvent recovery, which solves the problem that the dehydration capacity of the molecular sieve in the prior art is lower than the designed processing capacity of the molecular sieve and has the characteristics of high dehydration and regeneration efficiency.
[0005] The technical solution adopted by the present utility model is a molecular sieve dehydration and regeneration device for solvent recovery, which includes a molecular sieve tank, a crude solvent tank, a heat exchanger, a combined heat exchanger, a fan and a phase separation tank. The top of the molecular sieve tank is provided with a plurality of inlets and outlets, and the bottom of the molecular sieve tank is also provided with a plurality of inlets and outlets; the top of the phase separation tank is provided with an overflow port and an inlet, and the bottom of the phase separation tank is provided with an outlet; the top of the crude solvent tank is provided with two inlets, and the bottom of the crude solvent tank is provided with an outlet; the inlet at the top of the molecular sieve tank is connected to the outlet of the heat exchanger through a pipeline, the outlet at the top of the molecular sieve tank is connected to the rectification device through a pipeline, the inlet at the bottom of the molecular sieve tank is connected to the outlet of the crude solvent tank through a pipeline, one outlet at the bottom of the molecular sieve tank is connected to one inlet of the crude solvent tank through a pipeline, the other outlet at the bottom of the molecular sieve tank is connected to the inlet of the combined heat exchanger through a pipeline, a nitrogen inlet pipe is connected to the top of the molecular sieve tank, and the nitrogen inlet pipe is connected to a nitrogen source; the heat exchanger and the combined heat exchanger are connected through a pipeline, the fan is arranged on the connecting pipeline between the heat exchanger and the combined heat exchanger, the bottom of the combined heat exchanger is connected to the inlet at the top of the phase separation tank through a pipeline, the overflow port at the top of the phase separation tank is connected to the other inlet of the crude solvent tank through a pipeline, and the outlet at the bottom of the phase separation tank is connected to the wastewater treatment device through a pipeline.
[0006] The features of the present utility model further lie in:
[0007] For the molecular sieve dehydration and regeneration device for solvent recovery, a pump is provided on the pipeline connecting the inlet at the bottom of the molecular sieve tank and the outlet of the crude solvent tank.
[0008] For the molecular sieve dehydration and regeneration device for solvent recovery, the heat exchanger is externally connected to a heat conduction oil circulation heat source, and the combined heat exchanger is externally connected to two kinds of circulating cold sources, namely cooling water and chilled water, in sequence.
[0009] For the molecular sieve dehydration and regeneration device for solvent recovery, a nitrogen discharge pipe is communicated on the connecting pipeline between the fan and the heat exchanger, and the nitrogen discharge pipe is connected to the total waste gas inlet; a nitrogen supplement pipe is communicated on the connecting pipeline between the heat exchanger and the inlet at the top of the molecular sieve tank, and the nitrogen supplement pipe is connected to a nitrogen source.
[0010] For the molecular sieve dehydration and regeneration device for solvent recovery, two or more molecular sieve tanks are provided.
[0011] Molecular sieve dehydration and regeneration device for solvent recovery. The molecular sieve tank includes a tank body, and a filler is arranged in the tank body. In the center of the top of the tank body, there is a maintenance port A. Below the maintenance port A, there is a nitrogen inlet, and the nitrogen inlet is connected to the outlet of the heat exchanger through a pipeline. At the top of the tank body, there are a low-pressure nitrogen inlet and a dry solvent outlet. The low-pressure nitrogen inlet is connected to a nitrogen inlet pipe, and the dry solvent outlet is connected to a rectification device through a pipeline. In the center of the bottom of the tank body, there is a maintenance port B. On the maintenance port B, there are a crude solvent outlet, a regeneration nitrogen outlet, and a crude solvent inlet. The crude solvent outlet is connected to the inlet of a crude solvent tank through a pipeline. The regeneration nitrogen outlet is connected to the inlet of a combined heat exchanger through a pipeline. The crude solvent inlet is connected to the outlet of a crude solvent tank through a pipeline.
[0012] The beneficial effects of the present utility model are as follows:
[0013] The structure of the present utility model is simple and convenient to use. As a processing module in the solvent recovery process, it dehydrates the solvent. The dehydration process sequentially includes water absorption, connected discharging, pressure feeding, drying, regeneration, and cooling. The condensed and recovered solvent and water are preliminarily separated in a phase separation tank. The entire processing process is safe and reliable, avoiding the risk of solvent explosion, effectively improving the solvent recovery rate, with high dehydration efficiency, environmental protection and no pollution, saving labor costs, and avoiding human operation errors. Description of the Drawings
[0014] Figure 1 It is a schematic structural diagram of the molecular sieve dehydration and regeneration device of the present utility model;
[0015] Figure 2 It is a schematic structural diagram of the molecular sieve tank in the molecular sieve dehydration and regeneration device of the present utility model.
[0016] In the figure, 1. fan, 2. heat exchanger, 3. combined heat exchanger, 4. nitrogen inlet pipe, 5. molecular sieve tank, 6. crude solvent tank, 7. pump, 8. phase separation tank, 9. maintenance port A, 10. nitrogen inlet, 11. low-pressure nitrogen inlet, 12. filler, 13. dry solvent outlet, 14. maintenance port B, 15. crude solvent outlet, 16. regeneration nitrogen outlet, 17. crude solvent inlet, 18. nitrogen discharge pipe, 19. nitrogen supplement pipe. Specific Embodiments
[0017] The present utility model will be described in detail below with reference to the drawings and specific embodiments.
[0018] The molecular sieve dehydration and regeneration device for solvent recovery provided by the present utility model is as Figure 1As shown in the figure, it includes a molecular sieve tank 5, a crude solvent tank 6, a heat exchanger 2, a combined heat exchanger 3, a fan 1, and a phase separation tank 8. The top of the molecular sieve tank 5 is provided with multiple inlets and outlets, and the bottom of the molecular sieve tank 5 is also provided with multiple inlets and outlets; the top of the phase separation tank 8 is provided with an overflow port and an inlet, and the bottom of the phase separation tank 8 is provided with an outlet; the top of the crude solvent tank 6 is provided with two inlets, and the bottom of the crude solvent tank 6 is provided with an outlet; the inlet at the top of the molecular sieve tank 5 is connected to the outlet of the heat exchanger 2 through a pipeline, the outlet at the top of the molecular sieve tank 5 is connected to the distillation device through a pipeline, the inlet at the bottom of the molecular sieve tank 5 is connected to the outlet of the crude solvent tank 6 through a pipeline, one outlet at the bottom of the molecular sieve tank 5 is connected to one inlet of the crude solvent tank 6 through a pipeline, the other outlet at the bottom of the molecular sieve tank 5 is connected to the inlet of the combined heat exchanger 3 through a pipeline, the top of the molecular sieve tank 5 is connected with a nitrogen inlet pipe 4, and the nitrogen inlet pipe 4 is connected to a nitrogen source; the heat exchanger 2 and the combined heat exchanger 3 are connected through a pipeline, the fan 1 is arranged on the connecting pipeline between the heat exchanger 2 and the combined heat exchanger 3, and the function of the fan 1 is to pressurize the nitrogen in the pipeline; the bottom of the combined heat exchanger 3 is connected to the inlet at the top of the phase separation tank 8 through a pipeline, the overflow port at the top of the phase separation tank 8 is connected to the other inlet of the crude solvent tank 6 through a pipeline, and the outlet at the bottom of the phase separation tank 8 is connected to the wastewater treatment device through a pipeline. The water in the phase separation tank 8 enters the wastewater treatment device for treatment.
[0019] A pump 7 is arranged on the pipeline connecting the inlet at the bottom of the molecular sieve tank 5 and the outlet of the crude solvent tank 6. The function of the pump 7 is to transport the solvent in the crude solvent tank 6 to the molecular sieve tank 5.
[0020] The heat exchanger 2 is externally connected to a heat-conducting oil circulation heat source to heat the nitrogen passing through the heat exchanger 2; the combined heat exchanger 3 is externally connected to two kinds of circulating cold sources, namely cooling water and chilled water in sequence, to cool the nitrogen passing through the heat exchanger 3 and to condense the solvent and water passing through the heat exchanger 3.
[0021] A nitrogen discharge pipe 18 is communicated on the connecting pipeline between the fan 1 and the heat exchanger 2, and the nitrogen discharge pipe 18 is connected to the total waste gas inlet; a nitrogen supplement pipe 19 is communicated on the connecting pipeline between the heat exchanger 2 and the inlet at the top of the molecular sieve tank 5, and the nitrogen supplement pipe 19 is connected to a nitrogen source. A regulating valve is arranged on each of the pipelines where the nitrogen supplement pipe 19 and the nitrogen discharge pipe 18 are located. By adjusting the rates of nitrogen discharge and supplement, the pressure in the system is ensured to be stable.
[0022] There are two or more molecular sieve tanks 5. Such as Figure 2As shown in the figure, the molecular sieve tank 5 includes a tank body, and a filler 12 is arranged in the tank body; a maintenance port A9 is arranged at the center of the top of the tank body, and a nitrogen inlet 10 is arranged below the maintenance port A9. The nitrogen inlet 10 is connected to the outlet of the heat exchanger 2 through a pipeline; a low-pressure nitrogen inlet 11 and a dry solvent outlet 13 are arranged at the top of the tank body. The low-pressure nitrogen inlet 11 is connected to the nitrogen inlet pipe 4, and the dry solvent outlet 13 is connected to the rectification device through a pipeline; a maintenance port B14 is arranged at the center of the bottom of the tank body, and a crude solvent outlet 15, a regeneration nitrogen outlet 16 and a crude solvent inlet 17 are arranged on the maintenance port B14. The crude solvent outlet 15 is connected to the inlet of the crude solvent tank 6 through a pipeline, the regeneration nitrogen outlet 16 is connected to the inlet of the combined heat exchanger 3 through a pipeline, and the crude solvent inlet 17 is connected to the outlet of the crude solvent tank 6 through a pipeline. The molecular sieve tank 5 is regularly maintained and repaired through the maintenance port A9 and the maintenance port B14.
[0023] The working process of the molecular sieve dehydration and regeneration device of the present utility model is specifically as follows:
[0024] 1. Water absorption
[0025] The solvent collected by desorption is stored in the crude solvent tank 6. The solvent in the crude solvent tank 6 enters the interior of the molecular sieve tank 5 from the crude solvent inlet 17 through the pump 7. The moisture in the solvent is absorbed by the filler 12 in the molecular sieve tank 5, and the dry solvent flows out from the dry solvent outlet 13 at the top of the molecular sieve tank 5, and then enters the rectification device through a pipeline for separation and purification.
[0026] 2. Connecting and discharging
[0027] When the molecular sieve tank 5 is saturated with water absorption, the molecular sieve tank 5 enters the connecting and discharging stage: nitrogen enters from the low-pressure nitrogen inlet 11 at the top of the molecular sieve tank 5 through the nitrogen inlet pipe 4. Under the action of gravity and nitrogen pressure, the solvent in the molecular sieve tank 5 is discharged to another regenerated molecular sieve tank 5 through the connecting pipeline.
[0028] 3. Pressing the material
[0029] Keep nitrogen entering from the low-pressure nitrogen inlet 11 at the top of the molecular sieve tank 5, and press the remaining solvent in the filler to the crude solvent tank 6 through the crude solvent outlet 15.
[0030] 4. Drying
[0031] After the pressing of the material is completed, the nitrogen heated by the heat exchanger 2 enters the molecular sieve tank 5 from the nitrogen inlet 10 to dry the filler in the molecular sieve tank 5. The nitrogen and the vaporized solvent enter the combined heat exchanger 3 from the regeneration nitrogen outlet 16 at the bottom of the molecular sieve tank 5 through the connecting pipeline. The vaporized solvent is condensed by the circulating cold source and then discharged to the phase separation tank 8.
[0032] 5. Regeneration
[0033] After drying, the bed in the molecular sieve tank 5 mainly contains moisture. High-temperature nitrogen heated by heat-conducting oil enters the molecular sieve tank 5 from the nitrogen inlet 10. The moisture is vaporized into water vapor, and the water vapor enters the combined heat exchanger 3 through the regeneration nitrogen outlet 16 at the bottom of the molecular sieve tank 5 via a connecting pipeline. The water vapor is condensed by the circulating cold source and then discharged to the phase separation tank 8. The moisture and solvent in the phase separation tank are separated by gravity. The wastewater is sent to the wastewater treatment device, and the solvent overflows from the top overflow port of the phase separation tank 8 and enters the crude solvent tank 6 to await dehydration.
[0034] 6. Cooling
[0035] The regenerated bed needs to be cooled before it can be used for solvent dehydration again because the water absorption effect is better at low temperatures. At this time, the heat-conducting oil heating circuit is closed, and the nitrogen in the circuit, after being cooled by the cooling water of the combined heat exchanger 3, enters the top of the molecular sieve tank 5 and exchanges heat with the molecular sieve bed. The gas phase exits from the bottom of the molecular sieve tank 5, and the nitrogen circulates continuously until the bed reaches the set temperature.
[0036] The nitrogen for drying, regeneration, and cooling is pressurized by the blower 1 and then passes through the heat exchanger 2, the molecular sieve tank 5, and the combined heat exchanger 3 in sequence to form a closed cycle. A nitrogen discharge pipe 18 is connected to the pipeline connecting the blower 1 and the heat exchanger 2. A nitrogen supply pipe 19 is connected to the pipeline at the top inlet of the heat exchanger 2 and the molecular sieve tank 5. A regulating valve is provided on each of the pipelines where the nitrogen supply pipe 19 and the nitrogen discharge pipe 18 are located. By adjusting the rates of nitrogen discharge and supply, the pressure stability within the system is ensured.
[0037] It can be seen from the above method that the molecular sieve dehydration and regeneration device of the present utility model is used for dehydration treatment in the solvent recovery process, which is safe and reliable, operates stably, is convenient for automatic control, and saves labor costs.
[0038] Embodiment 1
[0039] The molecular sieve dehydration and regeneration device for solvent recovery provided by the present utility model, as Figure 1As shown in the figure, it includes a molecular sieve tank 5, a crude solvent tank 6, a heat exchanger 2, a combined heat exchanger 3, a fan 1 and a phase separation tank 8. The top of the molecular sieve tank 5 is provided with multiple inlets and outlets, and the bottom of the molecular sieve tank 5 is also provided with multiple inlets and outlets; the top of the phase separation tank 8 is provided with an overflow port and an inlet, and the bottom of the phase separation tank 8 is provided with an outlet; the top of the crude solvent tank 6 is provided with two inlets, and the bottom of the crude solvent tank 6 is provided with an outlet; the inlet at the top of the molecular sieve tank 5 is connected to the outlet of the heat exchanger 2 through a pipeline, the outlet at the top of the molecular sieve tank 5 is connected to the distillation device through a pipeline, the inlet at the bottom of the molecular sieve tank 5 is connected to the outlet of the crude solvent tank 6 through a pipeline, one outlet at the bottom of the molecular sieve tank 5 is connected to one inlet of the crude solvent tank 6 through a pipeline, the other outlet at the bottom of the molecular sieve tank 5 is connected to the inlet of the combined heat exchanger 3 through a pipeline, the top of the molecular sieve tank 5 is connected with a nitrogen inlet pipe 4, and the nitrogen inlet pipe 4 is connected to a nitrogen source; the heat exchanger 2 and the combined heat exchanger 3 are connected through a pipeline, the fan 1 is arranged on the connecting pipeline between the heat exchanger 2 and the combined heat exchanger 3, the bottom of the combined heat exchanger 3 is connected to the inlet at the top of the phase separation tank 8 through a pipeline, the overflow port at the top of the phase separation tank 8 is connected to the other inlet of the crude solvent tank 6 through a pipeline, and the outlet at the bottom of the phase separation tank 8 is connected to the wastewater treatment device through a pipeline.
[0040] Example 2
[0041] On the basis of Example 1, a pump 7 is provided on the pipeline connecting the inlet at the bottom of the molecular sieve tank 5 and the outlet of the crude solvent tank 6. The heat exchanger 2 is externally connected to a heat-conducting oil circulation heat source, and the combined heat exchanger 3 is externally connected to two circulating cold sources of cooling water and chilled water in sequence. A nitrogen discharge pipe 18 is communicated on the connecting pipeline between the fan 1 and the heat exchanger 2, and the nitrogen discharge pipe 18 is connected to the total waste gas inlet; a nitrogen supplement pipe 19 is communicated on the connecting pipeline between the heat exchanger 2 and the inlet at the top of the molecular sieve tank 5, and the nitrogen supplement pipe 19 is connected to a nitrogen source.
[0042] Example 3
[0043] On the basis of Example 1, two molecular sieve tanks 5 are provided; the molecular sieve tank 5 includes a tank body, and a filler 12 is arranged in the tank body; a maintenance port A9 is arranged in the center of the top of the tank body, a nitrogen inlet 10 is arranged below the maintenance port A9, and the nitrogen inlet 10 is connected to the outlet of the heat exchanger 2 through a pipeline; a low-pressure nitrogen inlet 11 and a dry solvent outlet 13 are arranged at the top of the tank body, the nitrogen inlet 11 is connected to the nitrogen inlet pipe 4, and the dry solvent outlet 13 is connected to the distillation device through a pipeline; a maintenance port B14 is arranged in the center of the bottom of the tank body, a crude solvent outlet 15, a regeneration nitrogen outlet 16 and a crude solvent inlet 17 are arranged on the maintenance port B14, the crude solvent outlet 15 is connected to the inlet of the crude solvent tank 6 through a pipeline, the regeneration nitrogen outlet 16 is connected to the inlet of the combined heat exchanger 3 through a pipeline, and the crude solvent inlet 17 is connected to the outlet of the crude solvent tank 6 through a pipeline.
Claims
1. A molecular sieve dehydration regeneration device for solvent recovery, characterized in that: The invention comprises a molecular sieve tank (5), a crude solvent tank (6), a heat exchanger (2), a combined heat exchanger (3), a fan (1) and a phase separation tank (8), wherein the top of the molecular sieve tank (5) is provided with a plurality of inlets and outlets, and the bottom of the molecular sieve tank (5) is also provided with a plurality of inlets and outlets; the top of the phase separation tank (8) is provided with an overflow port and an inlet, and the bottom of the phase separation tank (8) is provided with an outlet; the top of the crude solvent tank (6) is provided with two inlets, and the bottom of the crude solvent tank (6) is provided with an outlet; the inlet at the top of the molecular sieve tank (5) is connected to the outlet of the heat exchanger (2) through a pipeline, the outlet at the top of the molecular sieve tank (5) is connected to the de-rectification device through a pipeline, the inlet at the bottom of the molecular sieve tank (5) is connected to the outlet of the crude solvent tank (6) through a pipeline, and the molecular sieve tank An outlet at the bottom of the molecular sieve tank (5) is connected to an inlet of the crude solvent tank (6) through a pipeline, another outlet at the bottom of the molecular sieve tank (5) is connected to the inlet of the combined heat exchanger (3) through a pipeline, and a nitrogen inlet pipe (4) is provided at the top of the molecular sieve tank (5), and the nitrogen inlet pipe (4) is connected to a nitrogen source; the heat exchanger (2) is connected to the combined heat exchanger (3) through a pipeline, the fan (1) is arranged on the connecting pipeline between the heat exchanger (2) and the combined heat exchanger (3), the bottom of the combined heat exchanger (3) is connected to the inlet of the top of the phase separation tank (8) through a pipeline, the overflow port at the top of the phase separation tank (8) is connected to another inlet of the crude solvent tank (6) through a pipeline, and the bottom outlet of the phase separation tank (8) is connected to a wastewater treatment device through a pipeline.
2. The molecular sieve dehydration regeneration device for solvent recovery according to claim 1, characterized in that: A pump (7) is provided on a pipeline connecting the bottom inlet of the molecular sieve tank (5) and the outlet of the crude solvent tank (6).
3. The molecular sieve dehydration regeneration device for solvent recovery according to claim 2, characterized in that: The heat exchanger (2) is externally connected to a heat transfer oil circulating heat source, and the combined heat exchanger (3) is externally connected to two circulating cold sources, cooling water and chilled water, in sequence.
4. The molecular sieve dehydration regeneration device for solvent recovery according to claim 3, characterized in that: The connecting pipeline between the fan (1) and the heat exchanger (2) is connected to a nitrogen discharge pipe (18), and the nitrogen discharge pipe (18) is connected to the exhaust gas main inlet; the connecting pipeline between the heat exchanger (2) and the top inlet of the molecular sieve tank (5) is connected to a nitrogen replenishment pipe (19), and the nitrogen replenishment pipe (19) is connected to a nitrogen source.
5. The molecular sieve dehydration regeneration device for solvent recovery according to claim 1, characterized in that: The molecular sieve tanks (5) are provided with more than two.
6. The molecular sieve dehydration regeneration device for solvent recovery according to claim 5, characterized in that: The molecular sieve tank (5) comprises a tank body, in which a filler (12) is arranged; an inspection port A (9) is arranged at the center of the top of the tank body, a nitrogen inlet (10) is arranged below the inspection port A (9), and the nitrogen inlet (10) is connected to the outlet of the heat exchanger (2) through a pipeline; a low-pressure nitrogen inlet (11) and a dry solvent outlet (13) are arranged at the top of the tank body, the low-pressure nitrogen inlet (11) is connected to the nitrogen inlet pipe (4), and the dry solvent outlet (13) is connected to the nitrogen inlet pipe (4). The tank body is connected to the de-rectification device through a pipeline; an inspection port B (14) is provided at the center of the bottom of the tank body, and a crude solvent outlet (15), a regeneration nitrogen outlet (16) and a crude solvent inlet (17) are provided on the inspection port B (14); the crude solvent outlet (15) is connected to the inlet of the crude solvent tank (6) through a pipeline, the regeneration nitrogen outlet (16) is connected to the inlet of the combined heat exchanger (3) through a pipeline, and the crude solvent inlet (17) is connected to the outlet of the crude solvent tank (6) through a pipeline.