Impurity removal system for oxygen-containing argon tail gas

Abstract

The present invention relates to an impurity removal system for oxygen-containing argon tail gas, which is arranged before a purification system and is used to process argon tail gas as a raw gas containing oxygen, carbon oxides, and nitrogen. The impurity removal system for oxygen-containing argon tail gas includes: a CO catalytic system for catalytically removing at least part of the oxygen and part of the carbon oxides in the raw gas and outputting the raw gas after the compounds are removed; a redox system for further removing the remaining oxygen in the raw gas after the compounds are removed due to the fluctuation of the oxygen content in the raw gas and outputting the raw gas after the oxygen is removed; and an adsorption dehydration and decarbonization system for removing water and carbon dioxide in the raw gas after the oxygen is removed and outputting the raw gas after dehydration and decarbonization. The system flow of the present invention is simple, and one less dehydration system is arranged than the existing process. It can achieve safe, efficient, and low-energy removal of impurities such as oxygen contained in the argon tail gas, which is convenient for the subsequent purification process.

Description

Technical Field

[0001] The invention belongs to the technical field of gas recovery, and in particular relates to an impurity removal system for oxygen-containing argon tail gas. Background Art

[0002] Industrial tail gas containing argon (argon tail gas) needs to be recovered to avoid direct discharge and waste of argon components. The treatment of argon tail gas must first remove various impurities and then purify it. The existing method of argon catalytic removal of oxygen and other impurities in argon tail gas has a process route of: CO catalytic system, CO2 removal and dehydration system, oxygen catalytic system, and dehydration system. It has the problems of complex process, many supporting equipment, high operating temperature, low safety, high investment, incomplete oxygen catalysis, and high energy consumption, making it difficult to achieve a satisfactory recovery effect. Summary of the invention

[0003] The purpose of the present invention is to provide an impurity removal system for oxygen-containing argon tail gas with simple process, low energy consumption, stable operation and high system safety.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] An impurity removal system for oxygen-containing argon tail gas is arranged before a purification system and is used to treat argon tail gas as a raw material gas containing oxygen, carbon oxides, and nitrogen. The impurity removal system for oxygen-containing argon tail gas comprises:

[0006] A CO catalytic system for catalytically removing at least part of the oxygen and part of the carbon oxides in the raw gas and outputting the raw gas after the compounds are removed;

[0007] A redox system for further removing the residual oxygen in the raw gas after the chemical compound removal due to the fluctuation of the oxygen content in the raw gas and outputting the raw gas after the oxygen is removed;

[0008] An adsorption dehydration and decarbonization system is used to remove water and carbon dioxide from the deoxygenated raw gas and output the dehydrated and decarbonized raw gas.

[0009] Preferably, the CO catalytic system comprises a CO catalytic furnace, a regenerator and a cooler connected in sequence.

[0010] Preferably, the CO catalytic system further includes a 1# electric heater disposed before the CO catalytic furnace.

[0011] Preferably, the redox system comprises a plurality of redox furnaces which perform redox and regeneration alternately.

[0012] Preferably, the redox system further comprises a redox regeneration component for providing regeneration gas to the redox furnace, and the redox regeneration component comprises a first redox regeneration pipeline connected from the purification system to the redox furnace.

[0013] Preferably, the redox regeneration component further includes a 2# electric heater and a second redox regeneration pipeline connected from the purification system to the redox furnace via the 2# electric heater.

[0014] Preferably, the second redox regeneration pipeline passes through the regenerator and then passes through the 2# electric heater.

[0015] Preferably, the adsorption dehydration and decarbonization system includes a plurality of adsorption cylinders which alternately perform adsorption dehydration and decarbonization and regeneration.

[0016] Preferably, the adsorption dehydration and decarbonization system further comprises a dehydration and decarbonization regeneration component for providing regeneration gas to the adsorption cylinder, and the dehydration and decarbonization regeneration component comprises a first dehydration and decarbonization regeneration pipeline connected from the purification system to the adsorption cylinder.

[0017] Preferably, the dehydration and decarbonization regeneration component further includes a 3# electric heater and a second dehydration and decarbonization regeneration pipeline connected from the purification system to the adsorption cylinder via the 3# electric heater.

[0018] Due to the application of the above technical scheme, the present invention has the following advantages compared with the prior art: the system flow of the present invention is simple, and one less dehydration system is required compared with the prior art. It can remove impurities such as oxygen contained in argon tail gas in a safe, efficient and low-energy manner, which is convenient for subsequent purification processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Attached Figure 1 It is a schematic diagram of embodiment 1 of the present invention.

[0020] In the above figures: 1, 1# electric heater; 2, CO catalytic furnace; 3, regenerator; 4, cooler; 5, 1# redox furnace; 6, 2# redox furnace; 7, 2# electric heater; 8, 1# adsorption cylinder; 9, 2# adsorption cylinder; 10, 3# electric heater; 11, purification system. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings.

[0022] Embodiment 1: An impurity removal system for oxygen-containing argon tail gas is used to treat argon tail gas as raw material gas to remove impurities therein. The argon tail gas mainly contains Ar, and also contains impurities such as CO, O2, N2, CO2, H2O, etc.

[0023] As attached Figure 1 As shown, the impurity removal system for oxygen-containing argon tail gas includes a CO catalytic system, an oxidation-reduction system, an adsorption dehydration and decarbonization system, and is then connected to a purification system 11.

[0024] The impurity removal system for oxygen-containing argon tail gas is used to treat argon tail gas as raw material gas containing impurities such as oxygen, carbon oxides, and nitrogen. The filtered and compressed argon tail gas / raw material gas is sent to the impurity removal system for treatment.

[0025] The CO catalytic system is used to catalytically remove at least part of the oxygen and part of the carbon oxides in the raw gas, and output the raw gas after the compounds are removed. There is CO remaining in the raw gas after the compounds are removed, and CO is not completely catalyzed to generate CO2, which reduces the CO2 load of the subsequent adsorption dehydration and decarbonization system. The raw gas after filtration and compression passes through the CO catalytic system. Under the condition that the oxygen content in the argon tail gas is stable, the oxygen content in the argon tail gas can be reduced to below 1ppm and part of the CO can be removed. However, when the oxygen content in the argon tail gas fluctuates violently, the CO catalytic system cannot reduce the oxygen content to below 1ppm and can only remove most of the oxygen.

[0026] The CO catalytic system includes a CO catalytic furnace 2, a regenerator 3 and a cooler 4 which are connected in sequence through connecting pipes and necessary valves, instruments and other components, and may also include a 1# electric heater 1 arranged before the CO catalytic furnace 2. The filtered and compressed argon tail gas / raw gas is connected to the inlet of the 1# electric heater 1, the outlet of the 1# electric heater 1 is connected to the inlet of the CO catalytic furnace 2, the outlet of the CO catalytic furnace 2 is connected to the catalytic gas inlet of the regenerator 3, the catalytic gas outlet of the regenerator 3 is connected to the inlet of the cooler 4, and the outlet of the cooler 4 is connected to the inlet of the redox system. CO catalysis uses the compression heat of the argon tail gas to directly catalyze, and the 1# electric heater 1 is only used when the equipment is first started or when the compression heat of the argon tail gas is insufficient.

[0027] The redox system is used to further remove the residual oxygen in the raw gas after the decomposition due to the fluctuation of the oxygen content in the raw gas, and output the deoxygenated raw gas. When the oxygen content in the raw gas fluctuates, causing the CO catalytic system to be unable to reduce the oxygen content to below 1ppm, the raw gas after the decomposition is further deoxygenated by the redox system, reducing the oxygen content to below 1ppm, so that the oxygen content in the deoxygenated raw gas is removed to meet the requirements of the subsequent purification system 11.

[0028] The redox system includes a plurality of redox furnaces that alternately perform redox and regeneration. In the present embodiment, two redox furnaces are provided, namely, redox furnace 1# 5 and redox furnace 2# 6, which are connected by connecting pipes and necessary valves, instruments and other components. The redox system also includes a redox regeneration assembly for providing regeneration gas to the redox furnace. The redox regeneration assembly includes a first redox regeneration pipeline connected to the redox furnace by a purification system 11, and also includes a second redox regeneration pipeline connected to the redox furnace by a second electric heater 7 and a second redox regeneration pipeline connected to the redox furnace by a purification system 11 through the second electric heater 7. The second redox regeneration pipeline can also pass through the regenerator 3 and then through the second electric heater 7.

[0029] Take the operation of the 1# redox furnace 5 and the regeneration of the 2# redox furnace 6 as an example: the argon tail gas after the CO catalytic system is connected to the inlet of the 1# redox furnace 5, and the outlet of the 1# redox furnace 5 is connected to the inlet of the adsorption dehydration and decarbonization system; the regeneration of the 2# redox furnace 6 uses H2 or the subsequent purification system 11 to concentrate the CO-containing gas. The H2 or the subsequent purification system 11 concentrates the CO-containing gas and enters the regeneration gas inlet of the regenerator 3 in the CO catalytic system through valve control when heating is required, and is preheated by the heat after catalysis. The regeneration gas outlet of the regenerator 3 is connected to the inlet of the 2# electric heater 7, and the 2# electric heater 7 is used to further heat the regeneration gas. The outlet of the 2# electric heater 7 is connected to the regeneration gas inlet of the 2# redox furnace 6. When heating is not required, the H2 or the subsequent purification system 11 concentrates the CO-containing gas and is directly sent to the regeneration gas inlet of the 2# redox furnace 6 through valve control. After the 1# redox furnace 5 is saturated, it is switched to the 2# redox furnace 6 for use through the valve. When the oxygen content in the argon tail gas fluctuates violently, part of the externally supplied H2 or CO gas can be used as the regeneration gas for the redox furnace. Under normal use, there is no need to equip this system with additional hydrogen production equipment, and the equipment is highly safe.

[0030] The adsorption dehydration and decarbonization system is used to remove water and carbon dioxide from the raw gas after deoxygenation, and output the raw gas after dehydration and decarbonization. The adsorption dehydration and decarbonization system includes a plurality of adsorption cylinders that are connected by connecting pipes and necessary valves, instruments and other components to alternately perform adsorption dehydration and decarbonization and regeneration. The adsorption cylinder is set according to the process requirements. In this embodiment, two adsorption cylinders for switching are set, namely 1# adsorption cylinder 8 and 2# adsorption cylinder 9. The adsorption dehydration and decarbonization system also includes a dehydration and decarbonization regeneration component for providing regeneration gas to the adsorption cylinder. The dehydration and decarbonization regeneration component includes a first dehydration and decarbonization regeneration pipeline connected to the adsorption cylinder by the purification system 11, and also includes a 3# electric heater 10, and a second dehydration and decarbonization regeneration pipeline connected to the adsorption cylinder by the purification system 11 after the 3# electric heater 10. After the CO2 and H2O generated by the reaction of the argon tail gas through the CO catalytic system and the redox system are removed by the adsorption dehydration and decarbonization system, they are sent to the purification system 11 for distillation to obtain qualified high-purity product argon gas. The dehydrated and decarbonized raw gas obtained after the adsorption dehydration and decarbonization system contains impurities such as CO and N2.

[0031] In the scheme of the present invention, the CO catalytic system has a low operating temperature and low energy consumption; the scheme of the present invention has one less dehydration system than the existing process, the load of the adsorption dehydration and decarbonization system is lower than the existing process, the oxidation-reduction system process is simple and easy to operate, and when the oxygen content in the argon tail gas fluctuates, the oxygen content in the argon tail gas can also be reduced to less than 1PPM. The present invention can achieve safe, efficient and low-energy catalytic removal of impurities such as oxygen in the argon tail gas.

[0032] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. An impurity removal system for oxygen-containing argon tail gas, arranged before the purification system, for treating argon tail gas containing oxygen, carbon oxides, and nitrogen as raw material gas, characterized in that: The impurity removal system for oxygen-containing argon tail gas comprises: A CO catalytic system for catalytically removing at least part of the oxygen and part of the carbon oxides in the raw gas and outputting the raw gas after the compounds are removed, wherein CO remains in the raw gas after the compounds are removed; the CO catalytic system comprises a CO catalytic furnace, a regenerator and a cooler connected in sequence; A redox system for further removing the residual oxygen in the raw gas after the decomposition due to the fluctuation of the oxygen content in the raw gas and outputting the deoxygenated raw gas, wherein the oxygen content in the deoxygenated raw gas is reduced to less than 1 ppm; An adsorption dehydration and decarbonization system for removing water and carbon dioxide from the deoxygenated raw gas and outputting the dehydrated and decarbonized raw gas, wherein the dehydrated and decarbonized raw gas contains CO and N2 impurities, and the dehydrated and decarbonized raw gas is sent to the purification system for distillation; The redox system includes a plurality of redox furnaces that alternately perform redox and regeneration; The redox system also includes a redox regeneration component for providing regeneration gas to the redox furnace, and the redox regeneration component includes a first redox regeneration pipeline connected from the purification system to the redox furnace; the redox regeneration component also includes a 2# electric heater and a second redox regeneration pipeline connected to the redox furnace from the purification system via the 2# electric heater; the second redox regeneration pipeline passes through the regenerator and then through the 2# electric heater.

2. The impurity removal system for oxygen-containing argon tail gas according to claim 1, characterized in that: The CO catalytic system further includes a 1# electric heater disposed before the CO catalytic furnace.

3. The impurity removal system for oxygen-containing argon tail gas according to claim 1, characterized in that: The adsorption dehydration and decarbonization system comprises a plurality of adsorption cylinders which alternately perform adsorption dehydration and decarbonization and regeneration.

4. The impurity removal system for oxygen-containing argon tail gas according to claim 3, characterized in that: The adsorption dehydration and decarbonization system further includes a dehydration and decarbonization regeneration component for providing regeneration gas to the adsorption cylinder. The dehydration and decarbonization regeneration component includes a first dehydration and decarbonization regeneration pipeline connected from the purification system to the adsorption cylinder.

5. The impurity removal system for oxygen-containing argon tail gas according to claim 4, characterized in that: The dehydration and decarbonization regeneration component also includes a 3# electric heater and a second dehydration and decarbonization regeneration pipeline connected from the purification system to the adsorption cylinder via the 3# electric heater.

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