Auxiliary desorption system for pressure swing adsorption of oil gas recovery device

Abstract

The utility model discloses an auxiliary desorption system for pressure swing adsorption of an oil gas recovery device, and relates to the technical field of VOCs desorption, the auxiliary desorption system for pressure swing adsorption of the oil gas recovery device comprises a nitrogen heater, a cooling heat exchanger and a plurality of instrument valves for switching desorption, the nitrogen heater is arranged on a main pipeline of a low-pressure nitrogen pipeline, and the cooling heat exchanger is arranged on the main pipeline of the low-pressure nitrogen pipeline. The low-pressure nitrogen pipeline is respectively communicated with a tank A interface I of the adsorption tank A and a tank B interface I of the adsorption tank B through two branches, a valve I is arranged on the branch of the low-pressure nitrogen pipeline communicated with the adsorption tank A, and a valve II is arranged on the branch of the low-pressure nitrogen pipeline communicated with the adsorption tank B. The nitrogen heater and the cooling heat exchanger are arranged, deep desorption is conducted on an adsorbent bed layer regularly through hot nitrogen, the effective adsorption volume of an adsorbent is increased, the adsorption efficiency is improved, and the service life of the adsorbent is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to VOCs desorption technical field, concretely is a kind of oil gas recovery device pressure swing adsorption's auxiliary desorption system. BACKGROUND

[0002] The mainstream process for treating VOCs in oil storage depot and loading in the current industry is "condensation+adsorption" process, generally using pressure swing adsorption to desorb VOCs adsorbed in adsorbent, and the adsorbent bed in adsorption process is operated alternately, so that the residual VOCs molecules in adsorbent cannot be desorbed by pressure swing desorption, which makes the adsorption volume of adsorbent smaller, thereby affecting the treatment efficiency and service life of adsorbent. Therefore, we propose an auxiliary desorption system for oil gas recovery device pressure swing adsorption, which can improve the adsorption efficiency and service life of adsorbent in adsorption system. SUMMARY

[0003] The utility model aims at providing an auxiliary desorption system for oil gas recovery device pressure swing adsorption, which solves the problem that traditional pressure swing desorption cannot desorb residual VOCs molecules in adsorbent, making the adsorption volume of adsorbent smaller, thereby affecting the treatment efficiency and service life of adsorbent.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: an auxiliary desorption system for oil gas recovery device pressure swing adsorption, comprising a nitrogen heater, a cooling heat exchanger and a plurality of switching desorption instrument valves, the nitrogen heater is arranged on the main line of low-pressure nitrogen pipeline, the low-pressure nitrogen pipeline is connected to the tank A interface one of adsorption tank A and the tank B interface one of adsorption tank B through two branches, and a valve one is arranged on the low-pressure nitrogen pipeline branch connected to adsorption tank A, and a valve two is arranged on the low-pressure nitrogen pipeline branch connected to adsorption tank B;

[0005] The tank A interface one of adsorption tank A and the tank B interface one of adsorption tank B are connected to two branches of output pipeline in communication, a valve three is arranged on the output pipeline branch connected to adsorption tank A, and a valve four is arranged on the output pipeline branch connected to adsorption tank B, and the output pipeline is connected to the next process section;

[0006] The tank A interface two of adsorption tank A and the tank B interface two of adsorption tank B are connected to two branches of waste gas pipeline in communication, a valve five is arranged on the waste gas pipeline branch connected to adsorption tank A, and a valve six is arranged on the waste gas pipeline branch connected to adsorption tank B, and the cooling heat exchanger is arranged on the main line of waste gas pipeline, and the waste gas pipeline is connected to the input end of condensation unit;

[0007] The tank A interface three of the adsorption tank A and the tank B interface three of the adsorption tank B are connected with two branches of a condensation circulation pipeline, a valve seven is arranged on the condensation circulation pipeline branch connected with the adsorption tank A, a valve eight is arranged on the condensation circulation pipeline branch connected with the adsorption tank B, the branches where the valve seven and the valve eight are arranged are connected with an input main line of the condensation circulation pipeline, a vacuum pump is arranged on the input main line of the condensation circulation pipeline, and the input main line of the condensation circulation pipeline is connected with an input end of a condensation unit.

[0008] An output end of the condensation unit is connected with an output main line of the condensation circulation pipeline, a valve nine and a valve ten are arranged on two branches of the output main line of the condensation circulation pipeline, and the two branches of the output main line of the condensation circulation pipeline are connected with the branches where the valve seven and the valve eight are arranged.

[0009] Preferably, the heat source of the nitrogen heater is steam or an electric heater.

[0010] Preferably, the nitrogen heater heats the nitrogen to 120-150 DEG C through the heat source.

[0011] Preferably, the cold source of the cooling heat exchanger is low-temperature medium of the condensation unit or glycol solution.

[0012] Preferably, the cooling heat exchanger cools the nitrogen to about 50 DEG C through the cold source.

[0013] Preferably, the condensation unit is a three-stage condensation, the waste gas of the condensation unit is returned through the condensation circulation pipeline, and the liquid output by the waste gas of the condensation unit is output to a liquid collector.

[0014] The utility model has the following beneficial effects:

[0015] 1. Regularly, the adsorbent bed is deeply desorbed by hot nitrogen, the effective adsorption volume of the adsorbent is increased, the adsorption efficiency is improved, and the service life of the adsorbent is prolonged.

[0016] 2. During the auxiliary desorption, the VOCs waste gas of high-temperature desorption is cooled through the cooling heat exchanger and is sent to the condensation unit for circulation treatment, no VOCs waste gas is generated during the auxiliary desorption, and the device continuously runs. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 It is the system principle drawing of the utility model;

[0018] Fig. 2 It is the principle drawing of the condensation unit position of the utility model.

[0019] In the figure: 1. Nitrogen heater; 2. Cooling heat exchanger; 3. Low-pressure nitrogen pipeline; 4. Adsorption tank A; 5. Adsorption tank B; 61. Valve one; 62. Valve two; 63. Valve three; 64. Valve four; 65. Valve five; 66. Valve six; 67. Valve seven; 68. Valve eight; 69. Valve nine; 610. Valve ten; 7. Output pipeline; 8. Exhaust gas pipeline; 9. Condensation unit; 10. Condensation circulation pipeline; 11. Vacuum pump; 12. Liquid collector. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] like Figs. 1-2 As shown, the utility model provides a technical solution: an auxiliary desorption system for pressure swing adsorption of an oil and gas recovery device, comprising a nitrogen heater 1, a cooling heat exchanger 2, and a plurality of instrument valves for switching desorption. The heat source of the nitrogen heater 1 is steam or an electric heater, and the nitrogen heater 1 heats the nitrogen to 120-150°C through the heat source. The cold source of the cooling heat exchanger 2 is the low-temperature medium of the condensing unit 9 or an ethylene glycol solution, and the cooling heat exchanger 2 cools the nitrogen to about 50°C through the cold source. The nitrogen heater 1 is arranged on the main line of the low-pressure nitrogen pipeline 3, and the low-pressure nitrogen pipeline 3 is connected to the tank A interface 1 of the adsorption tank A4 and the tank B interface 1 of the adsorption tank B5 through two branches, and a valve 1 61 is provided on the branch line of the low-pressure nitrogen pipeline 3 connected to the adsorption tank A4, and a valve 2 62 is provided on the branch line of the low-pressure nitrogen pipeline 3 connected to the adsorption tank B5.

[0022] Tank A interface 1 of adsorption tank A4 and tank B interface 1 of adsorption tank B5 are respectively connected to two branches of output pipeline 7, and a valve 3 63 is provided on the branch of output pipeline 7 connected to adsorption tank A4, and a valve 4 64 is provided on the branch of output pipeline 7 connected to adsorption tank B5. Output pipeline 7 is connected to the next process section;

[0023] Tank A port 2 of adsorption tank A4 and tank B port 2 of adsorption tank B5 are respectively connected to two branches of exhaust gas pipeline 8. A fifth valve 65 is provided on the branch of exhaust gas pipeline 8 connected to adsorption tank A4, and a sixth valve 66 is provided on the branch of exhaust gas pipeline 8 connected to adsorption tank B5. The cooling heat exchanger 2 is provided on the main exhaust gas pipeline 8, and the exhaust gas pipeline 8 is connected to the input end of the condensing unit 9.

[0024] The tank A interface three of the adsorption tank A4 and the tank B interface three of the adsorption tank B5 are connected with two branches of the condensation circulation pipeline 10 respectively, and a valve seven 67 is arranged on the branch of the condensation circulation pipeline 10 connected with the adsorption tank A4, a valve eight 68 is arranged on the branch of the condensation circulation pipeline 10 connected with the adsorption tank B5, the branches of the valve seven 67 and the valve eight 68 are connected with the input main line of the condensation circulation pipeline 10, a vacuum pump 11 is arranged on the input main line of the condensation circulation pipeline 10, and the input main line of the condensation circulation pipeline 10 is connected with the input end of the condensation unit 9;

[0025] The output end of the condensation unit 9 is connected with the output main line of the condensation circulation pipeline 10, a valve nine 69 and a valve ten 610 are arranged on two branches of the output main line of the condensation circulation pipeline 10 respectively, the two branches of the output main line of the condensation circulation pipeline 10 are connected with the branches of the valve seven 67 and the valve eight 68 respectively, the condensation unit 9 is a three-stage condensation, so that the organic components of the waste gas are condensed into liquid and separated out, the residual gas of the waste gas condensed by the condensation unit 9 returns to the adsorbent through the condensation circulation pipeline 10 for re-adsorption, the liquid separated out from the waste gas condensed by the condensation unit 9 is output to the liquid collector 12 for next step processing;

[0026] In use, the nitrogen gas is heated by the nitrogen heater 1 and then sent to the adsorption tank A4, the waste gas desorbed by the hot nitrogen gas is sent to the cooling heat exchanger 2 for cooling and then sent to the front-end condensation unit 9 for further processing; after the high-temperature nitrogen gas purges the adsorption tank A4 for about 1 hour, the adsorption tank A4 is cooled by normal-temperature nitrogen gas, and the cooling process lasts for about 1 hour, the adsorption tank B5 is switched to perform the nitrogen gas hot desorption, when one of the adsorption tanks performs the hot desorption / cooling, the other adsorption tank is still in the adsorption state, after the double-tank nitrogen gas hot desorption, the system is switched to the normal vacuum pump 11 variable pressure desorption working condition;

[0027] The auxiliary desorption of the adsorption tank A4 is described as follows:

[0028] The nitrogen gas is heated by the nitrogen heater 1 to about 120 DEG C and then sent to the adsorption tank A4, the waste gas containing VOCs after the hot desorption is sent to the cooling heat exchanger 2 through the valve five 65, cooled to about 50 DEG C and then sent to the front-end condensation unit 9; the adsorption tank B5 is still in the adsorption state, the residual gas of the condensed waste gas discharged from the condensation section enters the adsorption tank B5 through the valve ten 610 and is re-adsorbed, and then is discharged into the next process section through the valve four 64; at this time, the valve states of the example in the figure are as follows: the valve three 63, the valve nine 69, the valve seven 67, the valve eight 68, the valve two 62 and the valve six 66 are closed, and the valve four 64, the valve ten 610, the valve one 61 and the valve five 65 are opened.

[0029] It is to be noted that, in the present document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0030] While the embodiments of the present application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and alterations can be made therein without departing from the spirit and scope of the application, which is defined by the appended claims and their equivalents.

Claims

1. An auxiliary desorption system for pressure swing adsorption of an oil and gas recovery device, characterized by: The nitrogen heater (1) is arranged on the main line of the low-pressure nitrogen pipeline (3), the low-pressure nitrogen pipeline (3) is connected with the tank A interface one of the adsorption tank A (4) and the tank B interface one of the adsorption tank B (5) through two branches, and the branch of the low-pressure nitrogen pipeline (3) connected with the adsorption tank A (4) is provided with the valve one (61), and the branch of the low-pressure nitrogen pipeline (3) connected with the adsorption tank B (5) is provided with the valve two (62); The tank A interface one of the adsorption tank A (4) and the tank B interface one of the adsorption tank B (5) are connected with two branches of the output pipeline (7) respectively, and the branch of the output pipeline (7) connected with the adsorption tank A (4) is provided with the valve three (63), and the branch of the output pipeline (7) connected with the adsorption tank B (5) is provided with the valve four (64), and the output pipeline (7) is connected with the lower process section; The tank A interface two of the adsorption tank A (4) and the tank B interface two of the adsorption tank B (5) are connected with two branches of the waste gas pipeline (8) respectively, and the branch of the waste gas pipeline (8) connected with the adsorption tank A (4) is provided with the valve five (65), and the branch of the waste gas pipeline (8) connected with the adsorption tank B (5) is provided with the valve six (66), and the cooling heat exchanger (2) is arranged on the main line of the waste gas pipeline (8), and the waste gas pipeline (8) is connected with the input end of the condensing unit (9); The tank A interface three of the adsorption tank A (4) and the tank B interface three of the adsorption tank B (5) are connected with two branches of the condensing circulating pipeline (10) respectively, and the branch of the condensing circulating pipeline (10) connected with the adsorption tank A (4) is provided with the valve seven (67), and the branch of the condensing circulating pipeline (10) connected with the adsorption tank B (5) is provided with the valve eight (68), and the branches of the valve seven (67) and the valve eight (68) are connected with the input main line of the condensing circulating pipeline (10), and the input main line of the condensing circulating pipeline (10) is provided with the vacuum pump (11), and the input main line of the condensing circulating pipeline (10) is connected with the input end of the condensing unit (9); The output end of the condensing unit (9) is connected with the output main line of the condensing circulating pipeline (10), and the two branches of the output main line of the condensing circulating pipeline (10) are respectively provided with the valve nine (69) and the valve ten (610), and the two branches of the output main line of the condensing circulating pipeline (10) are connected with the branches of the valve seven (67) and the valve eight (68) respectively.

2. The auxiliary desorption system for a pressure swing adsorption of an oil and gas recovery device according to claim 1, characterized in that: The heat source of the nitrogen heater (1) is steam or an electric heater.

3. The auxiliary desorption system for a pressure swing adsorption of an oil and gas recovery device of claim 1, wherein: The nitrogen heater (1) heats the nitrogen to 120-150 DEG C through the heat source.

4. The auxiliary desorption system for a pressure swing adsorption of an oil and gas recovery device of claim 1, wherein: The cold source of the cooling heat exchanger (2) is the low-temperature medium or the ethylene glycol solution of the condensing unit (9).

5. The auxiliary desorption system for a pressure swing adsorption of an oil and gas recovery device of claim 1, wherein: The cooling heat exchanger (2) cools the nitrogen to about 50 DEG C through the cold source.

6. An auxiliary desorption system for a pressure swing adsorption of an oil and gas recovery device according to claim 1, characterized in that: The condensing unit (9) is a three-stage condensing, the waste gas and the remaining gas condensed by the condensing unit (9) are returned through the condensing circulating pipeline (10), and the liquid output by the waste gas condensed by the condensing unit (9) is output to the liquid collector (12).

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