Pressure swing adsorption desorption gas recovery device

Abstract

The utility model provides a pressure swing adsorption desorption gas recovery device, which belongs to the technical field of pressure swing adsorption desorption gas recovery and comprises a conversion absorption unit and a solvent regeneration unit. The conversion and absorption unit comprises a heat exchanger, a converter, a deaerator, a waste heat recoverer, a desorption gas cooler and an absorber which are communicated in sequence; the deaerator communicates with the heat exchanger; the solvent regeneration unit comprises a resolver, an NHD cooler and an NHD recoverer; the resolver is communicated with the NHD recoverer, and the resolver is also communicated with the NHD cooler; the absorber is communicated with the NHD recoverer, and the liquid outlet end of the absorber is communicated with the liquid inlet end of the resolver; the NHD cooler is communicated with the liquid outlet end of the absorber; and the NHD recoverer is communicated with the liquid inlet end of the resolver. According to the device, not only can hydrogen be recovered, but also CO, CO2, N2 and CH4 can be recovered, the recovery efficiency of desorption gas is greatly improved, and the problem of energy waste is also greatly reduced due to recovery and utilization of waste heat and reutilization of a solvent.

Description

Technical Field

[0001] The utility model belongs to the technical field of pressure swing adsorption analytical gas recovery, and in particular relates to a pressure swing adsorption analytical gas recovery device. Background Art

[0002] At present, pressure swing adsorption analysis gas is mainly a mixed gas containing hydrogen, CO, CO2, N2, CH4, etc. In traditional processes, pressure swing adsorption analysis gas recovery mostly adopts boiler incineration to produce steam, and mainly uses the hydrogen in the pressure swing adsorption analysis gas as thermal energy. There are problems such as large solvent loss, high energy consumption, low pressure swing adsorption analysis gas recovery rate, incomplete recovery, etc., resulting in a large waste of energy. Utility Model Content

[0003] The embodiment of the utility model provides a pressure swing adsorption analysis gas recovery device, which aims to solve the problem of low recovery rate and energy waste in the traditional pressure swing adsorption analysis gas recovery method.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a pressure swing adsorption analysis gas recovery device, including a conversion absorption unit and a solvent regeneration unit; the conversion absorption unit includes a heat exchanger, a converter, a deoxidizer, a waste heat recovery device, a analysis gas cooler and an absorber connected in sequence; the outlet end of the deoxidizer is connected to the inlet end of the heat exchanger through a fourth connecting pipeline; a first bypass valve is arranged on the first connecting pipeline between the deoxidizer and the waste heat recovery device, a fifth connecting pipeline is arranged between the heat exchanger and the waste heat recovery device, and the fifth connecting pipeline is connected to the first connecting pipeline; The solvent regeneration unit includes a parser, an NHD cooler and an NHD recoverer; the gas outlet end of the parser is connected to the NHD recoverer, and the liquid outlet end of the parser is connected to the NHD cooler; the outlet end of the absorber is connected to the NHD recoverer through a pipeline, and the liquid outlet end of the absorber is connected to the liquid inlet end of the parser through a third connecting pipeline, and a third bypass valve is provided on the third connecting pipeline; the NHD cooler is connected to the liquid outlet end of the absorber; the NHD recoverer is connected to the liquid inlet end of the parser through an NHD recovery pipeline, and an NHD recovery valve is provided on the NHD recovery pipeline.

[0005] In one achievable manner, the inlet end and the outlet end of the absorber are further provided with a self-circulation pipeline, and the self-circulation pipeline is provided with a self-circulation control valve.

[0006] In one achievable manner, the solvent regeneration unit further comprises a water replenishment pipeline connected to the analyzer, a water replenishment valve is provided on the water replenishment pipeline, and the water replenishment pipeline is connected to the NHD recovery pipeline.

[0007] In one feasible manner, an inter-stage heater is provided in the analyzer, the outlet end of the inter-stage heater is connected to the inlet end of the analysis gas cooler, the outlet end of the deoxidizer is connected to the inlet end of the inter-stage heater via a second connecting pipe, and a second bypass valve is provided on the second connecting pipe; the second connecting pipe is connected to the fourth connecting pipe, and a heat exchanger heating valve is provided on the fourth connecting pipe.

[0008] In one achievable manner, the deoxidizer is a packed tower filled with a deoxidation catalyst.

[0009] In one achievable manner, the heat exchanger is a shell-and-tube heat exchanger.

[0010] In one achievable manner, the waste heat recovery device adopts a straight-through heat exchanger.

[0011] In one achievable manner, the analytical gas cooler adopts a shell-and-tube heat exchanger.

[0012] Compared with the prior art, the pressure swing adsorption analysis gas recovery device provided by the utility model has the following beneficial effects: the analysis gas enters the heat exchanger tube, is heated by the analysis gas from the outlet of the deoxidizer shell, and then enters the converter. In the converter, carbon-containing compounds such as carbon monoxide and methane are oxidized to generate carbon dioxide. The analysis gas that has completed the conversion enters the deoxidizer. The oxygen in the analysis gas is catalyzed by the nickel catalyst loaded in the deoxidizer, reacts with hydrogen to generate water and releases a large amount of heat, which can remove the oxygen in the analysis gas. The high-temperature analysis gas after deoxygenation overflows from the deoxidizer and enters the heat exchanger shell to exchange heat with the original analysis gas, and then enters the waste heat recovery device. After two heat recovery, it enters the analysis gas cooler, and the waste heat recovery device produces steam as a byproduct. The heat exchange effect of the heat exchanger is controlled by the first bypass valve, and the bed temperature of the converter and the deoxidizer is controlled to improve the conversion effect.

[0013] The parsed gas is cooled by the parsed gas cooler and then enters the absorber. In the absorber, carbon dioxide and water are absorbed by the NHD absorption liquid. The pure hydrogen-nitrogen mixed gas passes through the NHD recovery device and enters the ammonia synthesis system to realize the recycling of the parsed gas. The NHD absorption liquid at the bottom of the absorber uses the third bypass valve to control the production volume of the NHD absorption liquid. The produced NHD absorption liquid enters the parser and uses high-temperature distillation to resolve carbon dioxide and water in the NHD absorption liquid. The NHD absorption liquid after impurities are removed is cooled by the NHD cooler and then enters the absorber, which reduces the temperature of the NHD absorption liquid and improves the absorption effect of the absorption liquid. The parsed impurity gas enters the shell side of the NHD recovery device, cools and recovers the entrained NHD absorption liquid, and the solvent is recycled by controlling the NHD recovery valve.

[0014] The device provided in this embodiment can not only recover hydrogen, but also recover CO, CO2, N2, and CH4, which greatly improves the recovery efficiency of the analyzed gas. Moreover, due to the recovery and utilization of waste heat and the reuse of solvents, the problem of energy waste is also greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of a pressure swing adsorption gas recovery device provided in an embodiment of the utility model;

[0016] Description of reference numerals:

[0017] 1. Heat exchanger; 2. Converter; 3. Deaerator; 4. Waste heat recovery device; 5. Analysis gas cooler; 6. Absorber; 7. Analysis device; 8. NHD cooler; 9. NHD recovery device; 10. Interstage heater; 11. First bypass valve; 12. Heat exchanger heating valve; 13. Second bypass valve; 14. Self-circulation control valve; 15. Third bypass valve; 16. NHD recovery valve; 17. Water supply valve. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] See also Figure 1 , the pressure swing adsorption analysis gas recovery device provided by the utility model is now described. The pressure swing adsorption analysis gas recovery device includes a conversion absorption unit and a solvent regeneration unit; the conversion absorption unit includes a heat exchanger 1, a converter 2, a deoxidizer 3, a waste heat recovery device 4, a analysis gas cooler 5 and an absorber 6 connected in sequence; the outlet end of the deoxidizer 3 is connected to the inlet end of the heat exchanger 1 through a fourth connecting pipeline; a first bypass valve 11 is provided on the first connecting pipeline between the deoxidizer 3 and the waste heat recovery device 4, and a fifth connecting pipeline is provided between the heat exchanger 1 and the waste heat recovery device 4, and the fifth connecting pipeline is connected to the first connecting pipeline; the solvent regeneration unit includes a deoxidizer. The analyzer 7, the NHD cooler 8 and the NHD recovery device 9; the gas outlet end of the analyzer 7 is connected to the NHD recovery device 9, and the liquid outlet end of the analyzer 7 is connected to the NHD cooler 8; the outlet end of the absorber 6 is connected to the NHD recovery device 9 through a pipeline, and the liquid outlet end of the absorber 6 is connected to the liquid inlet end of the analyzer 7 through a third connecting pipeline, and a third bypass valve 15 is provided on the third connecting pipeline; the NHD cooler 8 is connected to the liquid outlet end of the absorber 6; the NHD recovery device 9 is connected to the liquid inlet end of the analyzer 7 through the NHD recovery pipeline, and an NHD recovery valve 16 is provided on the NHD recovery pipeline.

[0020] Compared with the prior art, the pressure swing adsorption analysis gas recovery device provided by the utility model has the following beneficial effects: through the device provided by this embodiment, not only hydrogen can be recovered, but also CO, CO2, N2, and CH4 can be recovered, which greatly improves the recovery efficiency of the analysis gas, and due to the recovery and utilization of waste heat and the reuse of solvents, the problem of energy waste is also greatly reduced.

[0021] Carbon dioxide is an important greenhouse gas, and its emission needs to be reduced. NHD (Natriumhydroxid) solution is polyethylene glycol dimethyl ether, which has a large solubility for sulfide and carbon dioxide in the gas. It is a physical absorbent that can absorb both CO2 and H2S, and can effectively react with CO2 to form CO3. 2- ions, thereby achieving the absorption and recovery of CO2.

[0022] A first bypass valve 11 is installed between the heat exchanger 1, the deoxidizer 3 and the waste heat recovery device 4 to control the heat exchange effect of the heat exchanger 1, control the reaction temperature of the converter 2 and the deoxidizer 3, and improve the conversion effect of the analytical gas.

[0023] The NHD cooler 8 can reduce the temperature of the NHD absorption liquid after regeneration, improve the absorption effect of the absorption liquid, and improve the recovery rate of the analyzed gas.

[0024] Among them, the NHD recoverer 9 cools and recovers the entrained NHD absorption liquid to reduce the loss of the NHD absorption liquid. The NHD recovery pipeline is provided with a water replenishment automatic control valve to control the water content of the NHD absorption liquid in the analyzer 7, increase the gas extraction volume of the analyzer 7, improve the analysis effect of the analyzer 7, improve the absorption effect of the absorption liquid after regeneration, and improve the recovery and utilization rate of the analyzed gas.

[0025] In some embodiments, Figure 1 As shown, the inlet end and the outlet end of the absorber 6 are also provided with self-circulation pipelines, and a self-circulation control valve 14 is provided on the self-circulation pipelines.

[0026] In some embodiments, Figure 1 As shown, the solvent regeneration unit further includes a water supply pipeline connected to the analyzer 7, a water supply valve 17 is provided on the water supply pipeline, and the water supply pipeline is connected to the NHD recovery pipeline.

[0027] In some embodiments, Figure 1As shown, the resolver 7 is provided with an inter-stage heater 10, and the outlet of the inter-stage heater 10 is connected to the inlet of the analytical gas cooler 5; the outlet of the deoxidizer 3 is connected to the inlet of the inter-stage heater 10 through a second connecting pipeline, and a second bypass valve 13 is provided on the second connecting pipeline. The second connecting pipeline is connected to the fourth connecting pipeline, and a heat exchanger heating valve 12 is provided on the fourth connecting pipeline. Among them, the resolver 7 adopts a continuous distillation packed tower, and the tower is provided with an inter-stage heater 10, which is connected to the second bypass valve 13. The high-temperature analytical gas at the outlet of the deoxidizer 3 is used to continuously heat the absorption liquid, thereby improving the analytical effect of the resolver 7 and the absorption effect of the absorption liquid after regeneration.

[0028] In some embodiments, Figure 1 As shown, the deoxidizer 3 is a packed tower filled with a deoxidation catalyst. The packed tower is filled with an oxidation catalyst for converting carbon monoxide and methane and other carbon-containing compounds in the desorbed gas to generate carbon dioxide. Preferably, the deoxidation catalyst uses a nickel-based deoxidizer to remove oxygen in the desorber 7, while releasing a large amount of heat to increase the desorbed gas temperature.

[0029] Alternatively, if Figure 1 As shown, the heat exchanger 1 is a shell-and-tube heat exchanger, which is used to increase the temperature of the analytical gas, control the stability of the catalyst bed temperature, improve the catalytic effect of the catalyst, extend the service life of the catalyst, control the reaction temperature of the converter 2 and the deoxidizer 3, and improve the conversion effect and deoxidation effect of the carbon-containing compounds.

[0030] Alternatively, if Figure 1 As shown, the waste heat recovery device 4 adopts a straight-through heat exchanger to recover the heat in the analytical gas and produce steam as a by-product, thereby achieving the purpose of energy saving and consumption reduction.

[0031] Alternatively, if Figure 1 As shown, the analytical gas cooler 5 adopts a shell-and-tube heat exchanger for cooling the analytical gas, reducing the temperature, and improving the absorption effect of impurities.

[0032] A possible use process of the pressure swing adsorption analytical gas recovery device provided by the utility model is as follows: Figure 1As shown, the arrow direction is the direction of gas-liquid flow. The parsed gas enters the tube side of the heat exchanger 1, is heated by the parsed gas from the shell side outlet of the deoxidizer 3, and then enters the converter 2. In the converter 2, carbon monoxide, methane and other carbon-containing compounds are oxidized to generate carbon dioxide. The parsed gas that has completed the conversion enters the deoxidizer 3. The oxygen in the parsed gas is catalyzed by the nickel catalyst loaded in the deoxidizer 3, reacts with hydrogen to generate water and releases a large amount of heat, which can remove the oxygen in the parsed gas; the high-temperature parsed gas after deoxygenation overflows from the deoxidizer 3 and enters the shell side of the heat exchanger 1 to exchange heat with the original parsed gas, and then enters the waste heat recovery device 4. After two heat recovery, it enters the parsed gas cooler 5, and the waste heat recovery device 4 produces steam as a byproduct. The heat exchange effect of the heat exchanger 1 is controlled by the first bypass valve 11, and the bed temperature of the converter 2 and the deoxidizer 3 is controlled to improve the conversion effect.

[0033] The analyzed gas is cooled by the analyzed gas cooler 5 and then enters the absorber 6. In the absorber 6, carbon dioxide and water are absorbed by the NHD absorbent. The pure hydrogen-nitrogen mixed gas enters the ammonia synthesis system after passing through the NHD recovery device 9, so as to realize the recovery and utilization of the analyzed gas. The NHD absorbent at the bottom of the absorber 6 is self-circulated through the self-circulation control valve 14 and the third bypass valve 15 to control the production amount of the NHD absorbent. The produced NHD absorbent enters the analyzer 7, and the carbon dioxide and water in the NHD absorbent are analyzed by high-temperature distillation. The NHD absorbent after impurities are removed is cooled by the NHD cooler 8 and then enters the absorber 6, so that the temperature of the NHD absorbent is reduced, which can improve the absorption efficiency of the absorbent. The NHD recovery effect is improved; the inter-stage heater 10 is provided in the analyzer 7 to continuously heat the NHD absorption liquid to improve the analysis effect. The inter-stage heater 10 utilizes the heat of the high-temperature analysis gas through the second bypass valve 13, and there is no need to add a heating device, so that the heat is recovered and the energy consumption is reduced; the impurity gas analyzed enters the shell side of the NHD recovery device 9, and the entrained NHD absorption liquid is cooled and recovered, and the solvent is recovered and utilized by controlling the NHD recovery valve 16; a water replenishment automatic control valve is provided on the NHD recovery pipeline to control the water content of the NHD absorption liquid in the analyzer 7, increase the gas lifting amount of the analyzer 7, improve the regeneration effect of the analyzer 7, improve the absorption effect of the NHD absorption liquid after regeneration, and improve the recovery rate of the analysis gas.

[0034] Compared with the prior art, the pressure swing adsorption analysis gas recovery device provided in the embodiment of the utility model: (1) adopts a shell-and-tube heat exchanger to recover the heat in the analysis gas, increase the temperature of the analysis gas entering the converter 2, maintain the catalyst bed temperature stable, improve the catalytic effect of the catalyst, and extend the service life of the catalyst.

[0035] (2) Using a mixed oxidation catalyst, carbon monoxide and methane in the analytical gas are converted into carbon dioxide, thereby improving the efficiency of analytical gas recovery and solving the problem of incomplete analytical gas recovery.

[0036] (3) Control the reaction temperature of the converter 2 and the deoxidizer 3 to improve the conversion effect of carbon-containing compounds; control the carbon dioxide content in the absorption liquid by adjusting the third bypass, improve the absorption effect of carbon dioxide, reduce the exhaust gas emission of carbon dioxide, and reduce the greenhouse effect of the environment.

[0037] (4) Continuous heating analysis is performed in the form of inter-stage heating, and the water content of the absorption liquid in the analyzer 7 is adjusted by the water replenishment automatic control valve, so as to increase the gas extraction amount during analysis, improve the regeneration effect of the analyzer 7, and improve the absorption effect of the absorption liquid, thereby solving the problem of low recovery rate of the analyzed gas.

[0038] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0039] The above description is only a preferred embodiment of the present invention and is 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 in the protection scope of the present invention.

Claims

1. A pressure swing adsorption gas recovery device, It is characterized in that include: It includes a conversion absorption unit and a solvent regeneration unit; The conversion and absorption unit comprises a heat exchanger (1), a converter (2), a deoxidizer (3), a waste heat recovery device (4), a desorption gas cooler (5) and an absorber (6) which are connected in sequence; the outlet end of the deoxidizer (3) is connected to the inlet end of the heat exchanger (1) via a fourth connecting pipeline; a first bypass valve (11) is provided on the first connecting pipeline between the deoxidizer (3) and the waste heat recovery device (4); a fifth connecting pipeline is provided between the heat exchanger (1) and the waste heat recovery device (4), and the fifth connecting pipeline is connected to the first connecting pipeline; The solvent regeneration unit comprises a resolver (7), an NHD cooler (8) and an NHD recoverer (9); the gas outlet end of the resolver (7) is connected to the NHD recoverer (9), and the liquid outlet end of the resolver (7) is connected to the NHD cooler (8); The outlet end of the absorber (6) is connected to the NHD recovery device (9) through a pipeline, the liquid outlet end of the absorber (6) is connected to the liquid inlet end of the resolver (7) through a third connecting pipeline, and a third bypass valve (15) is provided on the third connecting pipeline; the NHD cooler (8) is connected to the liquid outlet end of the absorber (6); the NHD recovery device (9) is connected to the liquid inlet end of the resolver (7) through an NHD recovery pipeline, and an NHD recovery valve (16) is provided on the NHD recovery pipeline.

2. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The inlet end and the outlet end of the absorber (6) are also provided with a self-circulation pipeline, and the self-circulation pipeline is provided with a self-circulation control valve (14).

3. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The solvent regeneration unit further comprises a water replenishment pipeline connected to the analyzer (7), a water replenishment valve (17) is arranged on the water replenishment pipeline, and the water replenishment pipeline is connected to the NHD recovery pipeline.

4. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The analyzer (7) is provided with an inter-stage heater (10), the outlet end of the inter-stage heater (10) is connected to the inlet end of the analytical gas cooler (5); the outlet end of the deoxidizer (3) is connected to the inlet end of the inter-stage heater (10) via a second connecting pipeline, and a second bypass valve (13) is provided on the second connecting pipeline; the second connecting pipeline is connected to the fourth connecting pipeline, and a heat exchanger heating valve (12) is provided on the fourth connecting pipeline.

5. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The deoxidizer (3) is a packed tower filled with a deoxidation catalyst.

6. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The heat exchanger (1) is a shell-and-tube heat exchanger.

7. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The waste heat recovery device (4) adopts a straight-through heat exchanger.

8. The pressure swing adsorption gas recovery device according to claim 1, It is characterized in that The analytical gas cooler (5) is a shell-and-tube heat exchanger.

Images