High-purity carbon dioxide gas repurification device and method

Abstract

The present invention discloses a high-purity carbon dioxide gas repurification device, comprising a gas source tank, a first booster pump, three adsorption towers, a gas storage unit, three gas outlet control units, three space replacement components, three filling control components, three heat exchange components, three pumping components, and three self-operated three-way temperature control valves for liquid outlet. The liquid inlet ends are respectively connected to the bottoms of the three heat exchange components, the hot liquid outlet ends are connected to the heat exchange components, and the cold liquid outlet ends are connected to the cold storage components. The coolant inside the heat exchange components, the cold storage components, the self-operated three-way temperature control valves for liquid outlet, and the pumping components is an incompressible cooling liquid. The present invention utilizes the cold absorption characteristic of the adsorption tower during the depressurization process, accumulates the refrigeration capacity generated therein, and utilizes it in the pressurization process; thus, the amount of high-purity carbon dioxide used for flushing and diluting the absorption tube can be reduced during the purification process.

Description

Technical Field

[0001] The present invention relates to the field of carbon dioxide gas purification, and in particular to a high-purity carbon dioxide gas re-purification device and method. Background Art

[0002] In industry, large amounts of carbon dioxide are obtained through calcination, fermentation gas recovery, combustion tail gas recovery, and by-product gas recovery. The concentration of the obtained carbon dioxide varies greatly depending on the source and the equipment used to obtain it. The carbon dioxide obtained by the calcination method and the carbon dioxide obtained by the combustion tail gas recovery method are of higher purity and can meet general use. However, for special fields and uses, it is necessary to meet the national standard for high-purity carbon dioxide. The main carbon dioxide purification technologies currently include physical absorption technology, chemical absorption technology, membrane separation technology, and pressure swing adsorption technology (PAS method).

[0003] Pressure swing adsorption (PSA) utilizes the selective adsorption properties of solid adsorbents for carbon dioxide. At high pressures, carbon dioxide is adsorbed and released after the pressure is reduced, thereby purifying the carbon dioxide and separating it from other gases. In the current PSA process, after pressurizing the carbon dioxide, high-purity CO2 is used to flush and dilute the unabsorbed gas in the adsorption tower. The flushing tail gas is not recycled until the concentration of the flushed CO2 reaches a certain value. Therefore, the high-purity CO2 used for flushing before the concentration of the flushed CO2 reaches a certain value is wasted, reducing production output.

[0004] During the pressure swing adsorption process, the pressure inside the adsorption tower increases and decreases periodically, so the surface temperature of the adsorption tower will also increase and decrease periodically. If the temperature is not cooled in time, heat will accumulate, causing the adsorption temperature to be too high, resulting in a safety hazard. At the same time, the cooling capacity is not utilized during the cooling process, resulting in energy waste. Summary of the Invention

[0005] In view of the above-mentioned defects of the prior art, the purpose of the present invention is to provide a high-purity carbon dioxide gas re-purification device, which transfers the heat generated during the pressurization process of the adsorption tower, and at the same time utilizes the cold absorption characteristics of the adsorption tower during the depressurization process to accumulate the refrigeration capacity generated and utilize it in its pressurization process, thereby reducing overall energy consumption and accelerating the cooling rate; during the purification process, the use of high-purity carbon dioxide for flushing and diluting the absorption tube can be reduced, thereby increasing production.

[0006] The objective of the present invention is achieved through such technical solution:

[0007] A high-purity carbon dioxide gas repurification device, including a purification and separation unit and a cooling unit;

[0008] The purification and separation unit comprises:

[0009] Gas source tank;

[0010] The first booster pump has an air inlet connected to the air source pipe through a main valve;

[0011] Three adsorption towers with adsorbent inside;

[0012] Gas storage unit;

[0013] Three gas outlet control units connect the three adsorption tower gas storage units in series to form a purification line; the three gas outlet control units are also connected to the gas source tank and the gas storage unit respectively; the gas outlet of the first booster pump is connected to the inside of the adsorption tower at the source of the purification line;

[0014] Three space replacement components are respectively arranged inside the adsorption tower;

[0015] Three filling control components are connected to the space replacement components inside the three adsorption towers respectively;

[0016] A third booster pump, the air inlet of which is connected to the return air valves of the three air outlet control units respectively, and the other end of which is connected to the air source tank;

[0017] a membrane separation device connected to the gas storage unit;

[0018] a solvent absorption device connected to the membrane separation device;

[0019] The cooling unit comprises:

[0020] Three heat exchange components are respectively wrapped around the outer surfaces of the three adsorption towers to exchange heat with the surfaces of the adsorption towers;

[0021] Three self-operated three-way temperature control valves with liquid inlets connected to the bottoms of the three heat exchange components, hot liquid outlets connected to the heat exchange components, and cold liquid outlets connected to the cold storage components;

[0022] Three pumping components, the liquid inlet ends of which are connected to the cold storage component and the heat exchange component respectively, and the liquid outlet ends of which are connected to the tops of the three heat exchange components;

[0023] The coolant inside the heat exchange component, heat transfer component, cold storage component, liquid outlet self-operated three-way temperature control valve and pumping component is an incompressible cooling liquid.

[0024] Furthermore, the gas outlet control unit includes:

[0025] The exhaust valve has one end connected to the interior of the adsorption tower and the other end connected to the outside atmosphere;

[0026] The return air valve has one end connected to the interior of the adsorption tower and the other end connected to the interior of the gas source tank;

[0027] A gas transmission valve, one end of which is connected to the interior of the adsorption tower;

[0028] A flushing valve, one end of which is connected to the gas storage unit and the other end of which is connected to the interior of the upstream adjacent adsorption tower;

[0029] A second booster pump, the air inlet end of which is connected to the other end of the air delivery valve, and the other end of which is connected to the downstream adsorption tower or gas storage unit;

[0030] The output bus has one end connected to the interior of the adsorption tower, and the other end connected to the exhaust valve, return air valve, and gas transmission valve;

[0031] a concentration sensor for detecting carbon dioxide concentration, connected to the output bus;

[0032] The gas outlet control unit between the two adsorption towers downstream of the purification line also includes a backflush valve, one end of which is connected to the output end of the second booster pump, and the other end is connected to the interior of the previous adsorption tower of the upstream adsorption tower.

[0033] Furthermore, the space replacement component includes:

[0034] A fixed plate is arranged at the upper part of the adsorption tower;

[0035] The elastically deformable airbag is fixed on the fixed plate to form a closed space with the fixed plate;

[0036] A vent pipe, one end of which passes through the adsorption tower and the fixed plate and is connected to the interior of the air bag, and the other end of which is connected to a filling control assembly;

[0037] a drawstring, one end of which is connected to the inner surface of the bottom of the airbag;

[0038] The lifting bucket is boxed with an opening facing upward, and the outer surface of the bottom is connected to the other end of the pull rope; the side wall of the lifting bucket is provided with a plurality of lower air inlet holes;

[0039] The lower end of the elastically deformable pulling cylinder is seamlessly connected to the opening of the lifting bucket, and the outer surface of the pulling cylinder is provided with a plurality of fully concave deformation guide grooves;

[0040] The fixed cylinder is box-shaped with an opening facing downward. The opening is seamlessly connected to the upper end of the pulling cylinder, and the top outer surface is fixed to the fixed plate. The side wall of the fixed cylinder is provided with a plurality of upper air inlet holes; the ventilation pipe passes through the adsorption tower, the fixed plate and the fixed cylinder in sequence and is connected to the inside of the pulling cylinder.

[0041] Furthermore, the filling control component includes:

[0042] A medium source tank, wherein the medium source tank contains compressible gas;

[0043] a fourth booster pump with a one-way valve, the inlet end of which is connected to the interior of the medium source tank, and the outlet end of which is connected to the vent pipe of the corresponding space replacement component;

[0044] a pressure relief valve, one end of which is connected to the vent pipe of the space displacement assembly;

[0045] The outlet ends of the fourth boost pumps of the three filling control assemblies are connected in sequence through pressure regulating valves.

[0046] Furthermore, the heat exchange component includes:

[0047] A plurality of heat-conducting fins are divided into a plurality of groups along the axis of the absorbent tank body, the heat-conducting fins in each group are arranged at the same interval; the heat-conducting fins in two adjacent groups are staggered, and a gap is left between the two adjacent groups of fins; the upper and lower end surfaces of the heat-conducting fins are acute-angled end surfaces; the heat-conducting fins are evenly arranged on the outer surface of the absorbent tank body along the axial direction of the absorbent tank body, and the two side end surfaces of the heat-conducting fins are seamlessly connected to the absorbent tank body and the thermal insulation layer respectively; the upper and lower parts of the thermal insulation layer leave an accommodating space from the top and lower ends of the absorbent tank body;

[0048] The heat insulation layer is wrapped around the outer surface of the absorbent tank and thinly covers the heat-conducting fins. The top of the heat insulation layer is provided with a liquid inlet connected to the pumping component, and the bottom is provided with a liquid outlet connected to the reflux automatic control component.

[0049] Furthermore, the heat exchange component includes:

[0050] The first liquid inlet interface of the plate heat exchanger is connected to the hot liquid outlet ends of three liquid outlet self-operated three-way temperature control valves;

[0051] The refrigeration component has two ends respectively connected to the second liquid inlet interface of the plate heat exchanger and the second liquid outlet interface connected to the liquid inlet interface;

[0052] The liquid storage tank is connected to the first liquid outlet interface of the plate heat exchanger and the three pumping components.

[0053] Furthermore, the pumping assembly comprises:

[0054] a first boost delivery pump, the liquid inlet of which is connected to the liquid storage tank, and the liquid outlet of which is connected to the interior of the heat exchange component;

[0055] a second booster delivery pump, the liquid inlet of which is connected to the cold storage component, and the liquid outlet of which is connected to the interior of the heat exchange component;

[0056] A pump-operated three-way temperature control valve, the liquid inlet of which is connected to the bottom of the heat exchange component;

[0057] A first pressure control valve is provided between the first booster delivery pump and the heat exchange assembly, the control end of the valve is connected to the cold liquid outlet of the pumping self-operated three-way temperature control valve, and the control end is provided with a first one-way valve connected to the outside;

[0058] The second pressure control valve is arranged between the second booster delivery pump and the heat exchange component, the control end of which is connected to the hot liquid outlet end of the pumping self-operated three-way temperature control valve, and the control end of which is provided with a first one-way valve connected to the outside;

[0059] The second one-way valve has two ends connected to the liquid storage tank and the cold storage assembly respectively, and controls the flow of coolant from the liquid storage tank to the cold storage assembly.

[0060] Furthermore, the cooling unit further comprises:

[0061] coolant container;

[0062] three pressurizing pumps, the liquid inlets of which are connected to the coolant container;

[0063] Two ends of the three third pressure control valves are respectively connected to the liquid outlets of the three pressure pumps and the tops of the three heat exchange components, and the control ends are connected to the bottoms of the heat exchange components.

[0064] A method for repurifying high-purity carbon dioxide gas comprises the following steps:

[0065] S1. Collect high-purity carbon dioxide gas obtained by other methods into a gas source tank, and inject high-pressure high-purity carbon dioxide gas into the gas outlet unit;

[0066] S2. Open the main valve, start the first booster pump, and pressurize the gas to be purified into the first adsorption tower until the pressure meets the adsorption requirements, then close the first booster pump and the main valve;

[0067] S3, the fourth booster pump connected to the first adsorption tower is operated to inflate the air bag in the adsorption tower, and at the same time, the exhaust valve connected to the first adsorption tower is opened to obtain the concentration sensor value;

[0068] If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve connected to the first adsorption;

[0069] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration for reuse, the exhaust valve connected to the first adsorption is closed, the return valve connected to the first adsorption is opened, and the third booster pump is started at the same time;

[0070] S4. After the airbag is fully expanded, the flushing valve connected to the first adsorption tower is opened, and high-pressure high-purity carbon dioxide is used to flush the first adsorption tower;

[0071] S5. Real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor;

[0072] If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve connected to the first adsorption;

[0073] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration for reuse, the exhaust valve connected to the first adsorption is closed, the return valve connected to the first adsorption is opened, and the third booster pump is started at the same time;

[0074] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be further adsorbed and purified, close the exhaust valve and the return valve connected to the first adsorption tower, open the gas supply valve connected to the first adsorption tower, and at the same time, start the second booster pump connected to the first adsorption tower to input the gas into the second adsorption tower;

[0075] S6, after the gas is injected into the second adsorption tower and reaches a predetermined pressure, stop injecting the gas into the second adsorption tower;

[0076] S7: The fourth booster pump connected to the second adsorption tower starts to inflate the air bag in the adsorption tower. At the same time, the exhaust valve connected to the second adsorption tower is opened to obtain the concentration sensor value.

[0077] If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through an exhaust valve connected to the second adsorption;

[0078] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be reused, close the exhaust valve connected to the second adsorption, open the return air valve connected to the second adsorption, and start the third booster pump at the same time;

[0079] S8. After the airbag is fully expanded, the flushing valve connected to the second adsorption tower is opened, and high-pressure high-purity carbon dioxide is used to flush the second adsorption tower;

[0080] S9, real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor;

[0081] If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through an exhaust valve connected to the second adsorption;

[0082] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be reused, close the exhaust valve connected to the second adsorption, open the return air valve connected to the second adsorption, and start the third booster pump at the same time;

[0083] If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be further adsorbed and purified, close the exhaust valve and return valve connected to the second adsorption tower, open the gas supply valve connected to the second adsorption tower, and at the same time, start the second booster pump connected to the second adsorption tower to input the gas into the next adsorption tower;

[0084] S10, the third adsorption tower operates according to the working steps of the second adsorption tower in steps S6 to S9, and finally injects the purified gas into the gas storage unit;

[0085] S11, the gas in the gas storage unit enters the membrane separation device to further purify the gas;

[0086] S12. The gas purified by the membrane separation equipment enters the solvent absorption equipment for further purification to obtain high-concentration carbon dioxide gas that meets national standards.

[0087] Furthermore, when the second adsorption tower begins to depressurize, when flushing the first adsorption tower, one or both of the backflush valve and the flush valve connected to the second adsorption tower can be opened to flush the first adsorption tower;

[0088] When the third adsorption tower starts to reduce pressure, when flushing the second adsorption tower, one or both of the backflush valve and the flush valve connected to the third adsorption tower can be opened to flush the second adsorption tower.

[0089] Due to the adoption of the above technical solution, the present invention has the following advantages:

[0090] 1. The heat exchange component contacts the adsorption tower body and conducts the heat generated inside the adsorption tower out of the adsorption tower to achieve the purpose of rapid pressurization; the refrigerant temperature can be reduced during the depressurization process of the adsorption tower, which can increase the pressure and cool the subsequent adsorption tower and reduce energy consumption.

[0091] 2. The system adopts a liquid outlet self-operated three-way temperature control valve. During the process of pressurization and depressurization of the adsorption tower, the system automatically switches the flow of refrigerant without external control equipment, so that heat is dissipated through the heat exchange component and the cold storage component cools the adsorption tower, reducing energy waste and lowering production costs.

[0092] 3. Each adsorption tower is connected to the downstream adsorption tower or gas storage unit through the gas outlet control unit, so that each adsorption tower only needs the carbon dioxide in the next-level adsorption and / or gas storage unit during the flushing process, and does not need to use high-concentration purified carbon dioxide, which reduces the consumption of carbon dioxide and can increase the production of carbon dioxide.

[0093] 4. Each adsorption tower can discharge the unabsorbed gas as directly as possible from the adsorption tower through the space replacement component before flushing, instead of discharging it by flushing and dilution, which reduces the consumption of gas with a higher carbon dioxide concentration than the gas source of the adsorption tower at this level and can increase the production of carbon dioxide.

[0094] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] The accompanying drawings of the present invention are as follows:

[0096] Figure 1 Schematic diagram of the structure of the purification and separation unit in the high-purity carbon dioxide gas re-purification device in this embodiment.

[0097] Figure 2 for Figure 1 Enlarged structural diagram at point A in the middle.

[0098] Figure 3 Schematic diagram of the cross-sectional structure of the adsorption tower in this embodiment.

[0099] Figure 4 for Figure 3 Enlarged structural diagram at point B in the middle.

[0100] Figure 5 Schematic diagram of the structure in which the cooling unit is connected to the three adsorption towers in the high-purity carbon dioxide gas re-purification device in this embodiment.

[0101] Figure 6 for Figure 5 Enlarged structural diagram at point C in the middle.

[0102] In the figure: 101. Gas source tank; 102. First booster pump; 103. Adsorption tower; 1031. Adsorbent; 104. Gas storage unit; 1051. Exhaust valve; 1052. Return valve; 1053. Gas delivery valve; 1054. Flushing valve; 1055. Second booster pump; 1056. Backflush valve; 1057. Output longitudinal bus; 1058. Concentration sensor; 1061. Fixing plate; 1062. Air bag; 1063. Ventilation pipe; 1064. Pull rope; 1065. Lifting bucket; 10651. Lower air inlet; 1066. Lifting cylinder; 10661. Deformation guide groove; 1067. Fixing cylinder; 10671. Upper air inlet; 1071. Medium source tank; 1072. Fourth booster pump; 1073. Pressure relief valve; 1074. Pressure regulating valve; 108. Third boosting pump; 109. Main valve; 110. Membrane separation equipment; 111. Solvent absorption equipment; 2011. Heat-conducting fins; 2012. Insulation layer; 202. Liquid outlet self-operated three-way temperature control valve; 2031. Plate heat exchanger; 2032. Refrigeration component; 2033. Liquid storage tank; 204. Cold storage component; 2051. First boosting delivery pump; 2052. Second boosting delivery pump; 2053. Pumping self-operated three-way temperature control valve; 2054. First pressure control valve; 2055. Second pressure control valve; 2056. First one-way valve; 2057. Second one-way valve; 2061. Coolant container; 2062. Pressure pump; 2063. Third pressure control valve. DETAILED DESCRIPTION

[0103] The present invention will be further described below with reference to the accompanying drawings and examples.

[0104] Example:

[0105] like Figures 1 to 6 As shown, the high-purity carbon dioxide gas re-purification device includes a purification and separation unit and a cooling unit;

[0106] The purification and separation unit comprises:

[0107] Gas source tank 101;

[0108] The first booster pump 102, the air inlet end of which is connected to the air source pipe through the main valve 109;

[0109] Three adsorption towers 103, each containing an adsorbent 1031;

[0110] Gas storage unit 104;

[0111] Three gas outlet control units connect the three adsorption towers 103 and the gas storage unit 104 in series to form a purification line; the three gas outlet control units are also connected to the gas source tank 101 and the gas storage unit 104 respectively; the gas outlet of the first booster pump 102 is connected to the inside of the adsorption tower 103 at the source of the purification line;

[0112] Three space replacement components are respectively arranged inside the adsorption tower 103;

[0113] Three filling control components are connected to the space replacement components inside the three adsorption towers 103 respectively;

[0114] The third booster pump 108 has an air inlet connected to the return air valves 1052 of the three air outlet control units, and the other end connected to the air source tank 101;

[0115] Membrane separation equipment 110 is in communication with the gas storage unit 104;

[0116] The solvent absorption device 111 is connected to the membrane separation device 110;

[0117] The cooling unit comprises:

[0118] Three heat exchange components are respectively wrapped around the outer surfaces of the three adsorption towers 103 to perform heat exchange with the surfaces of the adsorption towers 103;

[0119] Three self-operated three-way temperature control valves 202 for liquid discharge, with their liquid inlets connected to the bottoms of the three heat exchange assemblies, their hot liquid outlets connected to the heat exchange assemblies, and their cold liquid outlets connected to the cold storage assembly 204. The self-operated three-way temperature control valves 202 for liquid discharge, with their liquid inlets connected to the bottoms of the heat exchange assemblies, use the German FK-32-12.5-PN16-1 model, a single-pass type valve with only one liquid outlet.

[0120] Three pumping components, the liquid inlet ends of which are respectively connected to the cold storage component 204 and the heat exchange component, and the liquid outlet ends of which are connected to the tops of the three heat exchange components;

[0121] The coolant in the heat exchange assembly, heat transfer assembly, cold storage assembly 204, liquid outlet self-operated three-way temperature control valve 202 and pumping assembly is an incompressible cooling liquid. In this embodiment, cooling oil is selected as the coolant.

[0122] In this embodiment, the gas outlet control unit includes:

[0123] The exhaust valve 1051 has one end connected to the interior of the adsorption tower 103 and the other end connected to the outside atmosphere;

[0124] The return air valve 1052 has one end connected to the interior of the adsorption tower 103 and the other end connected to the interior of the gas source tank 101;

[0125] The gas delivery valve 1053 has one end in communication with the interior of the adsorption tower 103;

[0126] A flushing valve 1054 , one end of which is connected to the gas storage unit 104 and the other end of which is connected to the interior of the upstream adjacent adsorption tower 103 ;

[0127] The second booster pump 1055 has an air inlet end connected to the other end of the air delivery valve 1053 and another end connected to the downstream adsorption tower 103 or the air storage unit 104;

[0128] The output bus 1057 has one end connected to the interior of the adsorption tower 103 and the other end connected to the exhaust valve 1051, the return air valve 1052, and the gas delivery valve 1053;

[0129] The concentration sensor 1058 for detecting the carbon dioxide concentration is connected to the output bus 1057 .

[0130] The gas outlet control unit can select the direction of the gas discharged from the adsorption tower 103 according to the concentration of the unadsorbed gas discharged after pressurization and the carbon dioxide during the flushing process, so as to retain the carbon dioxide as much as possible and reduce the loss of carbon dioxide.

[0131] The gas outlet control unit between the two adsorption towers 103 downstream of the purification line also includes a backflush valve 1056, one end of which is connected to the output end of the second booster pump 1055, and the other end is connected to the interior of the previous adsorption tower 103 of the upstream adsorption tower 103.

[0132] Through the backflush valve 1056, the gas in the adsorption tower 103 no longer needs to rely on the high concentration of carbon dioxide in the gas outlet unit for flushing and dilution, which can reduce the waste of the carbon dioxide tower.

[0133] In this embodiment, the space replacement component includes:

[0134] The fixed plate 1061 is arranged at the upper part of the adsorption tower 103;

[0135] The elastically deformable airbag 1062 is fixed on the fixing plate 1061 and forms a closed space with the fixing plate 1061;

[0136] One end of the vent pipe 1063 passes through the adsorption tower 103 and the fixing plate 1061 and is connected to the interior of the air bag 1062, and the other end is connected to a filling control component.

[0137] By changing the space occupied by the air bag 1062 in the adsorption tower 103 through expansion and contraction, other gases that are not adsorbed in the adsorption tower 103 can be squeezed out of the adsorption tower 103 after pressurization is completed, thereby reducing the amount of carbon dioxide used in the flushing process during the subsequent depressurization process.

[0138] The lower portion of the airbag 1062 is in an inverted cone shape in a natural state. The space displacement assembly further includes a lifting unit disposed within the airbag 1062. The lifting unit includes:

[0139] a pull rope 1064 , one end of which is connected to the inner surface of the bottom of the air bag 1062 ;

[0140] The lifting bucket 1065 is box-shaped with its opening facing upward, and the outer surface of its bottom is connected to the other end of the pull rope 1064; the side wall of the lifting bucket 1065 is provided with a plurality of lower air inlet holes;

[0141] The lower end of the elastically deformable pulling cylinder 1066 is seamlessly connected to the opening of the lifting barrel 1065, and the outer surface of the pulling cylinder 1066 is provided with a plurality of fully concave deformation guide grooves 10661;

[0142] The fixed cylinder 1067 is box-shaped with an opening facing downward, and its opening is seamlessly connected to the upper end of the pulling cylinder 1066. The top outer surface is fixedly connected to the fixed plate 1061, and the side wall of the fixed cylinder 1067 is provided with a plurality of upper air inlet holes; the ventilation pipe 1063 passes through the adsorption tower 103, the fixed plate 1061 and the fixed cylinder 1067 in sequence and is connected to the interior of the pulling cylinder 1066.

[0143] The surface position of the airbag 1062 during expansion and contraction can be controlled by the pulling cylinder 1066, so that the airbag 1062 can occupy more space in the adsorption tower 103 when pressurized, and the airbag 1062 can be smoothly expanded.

[0144] In this embodiment, the filling control component includes:

[0145] A medium source tank 1071, wherein the medium source tank 1071 contains compressible gas;

[0146] A fourth booster pump 1072 with a one-way valve, the inlet of which is connected to the interior of the medium source tank 1071, and the outlet of which is connected to the vent pipe 1063 of the corresponding space replacement assembly;

[0147] a pressure relief valve 1073 , one end of which is in communication with the vent pipe 1063 of the space displacement assembly;

[0148] The outlet ends of the fourth boost pumps 1072 of the three filling control assemblies are connected in sequence through the pressure regulating valves 1074 .

[0149] Compressible gas is used as a medium source. When it releases pressure on the airbag 1062, its pressure and gas can be transferred to another adsorption tower 103 through the pressure regulating valve 1074, thereby reducing the power consumption and time of pressurizing the airbag 1062 of another adsorption tower 103.

[0150] In this embodiment, the heat exchange component includes:

[0151] A plurality of heat-conducting fins 2011 are divided into a plurality of groups along the axis of the absorbent tank body, wherein the heat-conducting fins 2011 in each group are arranged at the same interval; the heat-conducting fins 2011 in two adjacent groups are staggered, and a gap is left between the two adjacent groups of fins; the upper and lower end surfaces of the heat-conducting fins 2011 are acute-angled end surfaces; the heat-conducting fins 2011 are evenly arranged on the outer surface of the absorbent tank body along the axial direction of the absorbent tank body, and the two side end surfaces of the heat-conducting fins 2011 are seamlessly connected to the absorbent tank body and the thermal insulation layer 2012 respectively; the upper and lower portions of the thermal insulation layer 2012 leave an accommodation space from the top and lower ends of the absorbent tank body;

[0152] The heat-insulating layer 2012 is wrapped around the outer surface of the absorbent tank and thinly covers the heat-conducting fins 2011. The top of the heat-insulating layer is provided with a liquid inlet connected to the pumping component, and the bottom is provided with a liquid outlet connected to the reflux automatic control component.

[0153] The heat-conducting fins 2011 are arranged in groups with each group being staggered, so that the cooling oil flowing through the previous group of heat-conducting fins 2011 will directly collide with the next group of heat-conducting fins 2011, and the cooling oil is dispersed and mixed, thereby improving the heat exchange efficiency of the cooling oil.

[0154] In this embodiment, the heat exchange component includes:

[0155] The first liquid inlet port of the plate heat exchanger 2031 is connected to the hot liquid outlet ports of the three liquid outlet self-operated three-way temperature control valves 202;

[0156] The refrigeration component 2032 has two ends respectively connected to the second liquid inlet interface of the plate heat exchanger 2031 and the second liquid outlet interface connected to the liquid inlet interface;

[0157] The liquid storage tank 2033 is connected to the first liquid outlet interface of the plate heat exchanger 2031 and the three pumping components.

[0158] The plate heat exchanger 2031 has a high heat exchange efficiency, and the refrigeration component 2032 can select a single-stage refrigeration system or a multi-stage stacked refrigeration system according to the heat dissipation capacity requirements.

[0159] In this embodiment, the pumping assembly includes:

[0160] A first booster delivery pump 2051, whose liquid inlet is connected to the liquid storage tank 2033 and whose liquid outlet is connected to the interior of the heat exchange assembly;

[0161] A second booster delivery pump 2052, whose liquid inlet is connected to the cold storage assembly 204 and whose liquid outlet is connected to the interior of the heat exchange assembly;

[0162] A pump-operated three-way temperature control valve 2053, the liquid inlet of which is connected to the bottom of the heat exchange component;

[0163] The first pressure control valve 2054 is provided between the first booster delivery pump 2051 and the heat exchange assembly, with its control end being connected to the cold liquid outlet end of the pumping self-operated three-way temperature control valve 2053, and its control end being provided with a first check valve 2056 connected to the outside;

[0164] The second pressure control valve 2055 is provided between the second booster delivery pump 2052 and the heat exchange assembly, with its control end being connected to the hot liquid outlet end of the pumping self-operated three-way temperature control valve 2053, and its control end being provided with a first check valve 2056 connected to the outside;

[0165] The second one-way valve 2057 has two ends connected to the liquid storage tank 2033 and the cold storage assembly 204 respectively, and controls the flow of coolant from the liquid storage tank 2033 to the cold storage assembly 204.

[0166] The pumping self-operated three-way temperature control valve 2053 adopts the German FK-32-12.5-PN16-2 self-operated three-way temperature control valve. The self-operated three-way temperature control valve is multi-way, that is, it can discharge liquid from two outlets at the same time or only from one outlet.

[0167] The pumping self-operated three-way temperature control valve 2053 is externally connected through the first check valve 2056 on the first pressure control valve 2054 and the second pressure control valve 2055. After cooling oil flows into the pumping self-operated three-way temperature control valve 2053, it flows into the pumping self-operated three-way temperature control valve 2053, connecting with the control end of the first pressure control valve 2054 and / or the second pressure control valve 2055, thereby controlling the opening and / or closing of the first pressure control valve 2054 and / or the second pressure control valve 2055. After the first pressure control valve 2054 and / or the second pressure control valve 2055 are opened, the first booster pump 2051 and the second booster pump 2052 operate to deliver the cooled cooling oil in the liquid storage tank 2033 and the low-temperature cooling oil in the cold storage assembly 204 to the heat exchange assembly to cool the adsorption tower 103. Alternatively, when the second booster pump 2052 operates alone, the cooling capacity generated during the pressure reduction process of the adsorption tower 103 can be stored in the cooling oil.

[0168] In this embodiment, the cooling unit further includes:

[0169] Coolant container 2061;

[0170] Three pressure pumps 2062, with their liquid inlets connected to the coolant container 2061;

[0171] The three third pressure control valves 2063 have their two ends connected to the liquid outlets of the three pressure pumps 2062 and the tops of the three heat exchange components respectively, and their control ends connected to the bottoms of the heat exchange components.

[0172] As the first one-way valve 2056 continues to flow out cooling oil, the cooling oil in the system will decrease. At this time, the third pressure control valve 2063 adaptively controls whether the boosting pump 2062 replenishes cooling oil into the system based on the pressure of the cooling oil flowing out of the heat exchange component.

[0173] This embodiment

[0174] The steps for repurifying high-purity carbon dioxide gas are as follows: first, the purification device of this embodiment is set up according to Figure 1 、 Figure 5 、 Figure 6 Connect well.

[0175] S1. The high-purity carbon dioxide gas collected by other methods is concentrated into the gas source tank 101, and the high-pressure high-purity carbon dioxide gas is injected into the gas outlet unit;

[0176] S2. Open the main valve 109, start the first booster pump 102, and pressurize the gas to be purified and inject it into the first adsorption tower 103 until the pressure meets the adsorption requirements, then close the first booster pump 102 and the main valve;

[0177] S3: The fourth booster pump 1072 connected to the first adsorption tower 103 starts to inflate the air bag 1062 in the adsorption tower 103. At the same time, the exhaust valve 1051 connected to the first adsorption tower is opened to obtain the value of the concentration sensor 1058.

[0178] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 is lower than the minimum concentration for reuse, the gas is discharged through the exhaust valve 1051 connected to the first adsorption;

[0179] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration for reuse, the exhaust valve 1051 connected to the first adsorption is closed, the return air valve 1052 connected to the first adsorption is opened, and the third booster pump 108 is started at the same time;

[0180] S4. After the airbag 1062 is fully expanded, the flushing valve 1054 connected to the first adsorption tower 103 is opened, and the high-pressure high-purity carbon dioxide is flushed into the first adsorption tower 103;

[0181] S5. Real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor 1058;

[0182] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 is lower than the minimum concentration for reuse, the gas is discharged through the exhaust valve 1051 connected to the first adsorption;

[0183] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration for reuse, the exhaust valve 1051 connected to the first adsorption is closed, the return air valve 1052 connected to the first adsorption is opened, and the third booster pump 108 is started at the same time;

[0184] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration that can be further adsorbed and purified, the exhaust valve 1051 and the return gas valve 1052 connected to the first adsorption tower are closed, the gas supply valve 1053 connected to the first adsorption tower is opened, and the second booster pump 1055 connected to the first adsorption tower is simultaneously turned on to input the gas into the next adsorption tower 103;

[0185] S6, after the gas is injected into the second adsorption tower 103 and reaches a predetermined pressure, stop injecting the gas into the second adsorption tower 103;

[0186] S7: The fourth booster pump 1072 connected to the second adsorption tower 103 starts to inflate the air bag 1062 in the adsorption tower 103. At the same time, the exhaust valve 1051 connected to the second adsorption tower is opened to obtain the value of the concentration sensor 1058.

[0187] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve 1051 connected to the second adsorption;

[0188] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration for reuse, the exhaust valve 1051 connected to the second adsorption is closed, the return air valve 1052 connected to the second adsorption is opened, and the third booster pump 108 is started at the same time;

[0189] S8. After the airbag 1062 is fully expanded, the flushing valve 1054 connected to the second adsorption tower 103 is opened, and the high-pressure high-purity carbon dioxide is flushed into the second adsorption tower 103;

[0190] S9. Real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor 1058;

[0191] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve 1051 connected to the second adsorption;

[0192] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration for reuse, the exhaust valve 1051 connected to the second adsorption is closed, the return air valve 1052 connected to the second adsorption is opened, and the third booster pump 108 is started at the same time;

[0193] If the carbon dioxide concentration of the gas flowing through the concentration sensor 1058 reaches the minimum concentration that can be further adsorbed and purified, the exhaust valve 1051 and the return gas valve 1052 connected to the second adsorption tower are closed, the gas supply valve 1053 connected to the second adsorption tower is opened, and the second booster pump 1055 connected to the second adsorption tower is simultaneously turned on to input the gas into the next adsorption tower 103;

[0194] S10, the third adsorption tower 103 operates according to the working steps of the second adsorption tower 103 in steps S6 to S9, and finally injects the purified gas into the gas storage unit 104;

[0195] S11, the gas in the gas storage unit 104 enters the membrane separation device 110 to further purify the gas;

[0196] S12: The gas purified by the membrane separation device 110 enters the solvent absorption device 111 for further purification to obtain high-concentration carbon dioxide gas that meets national standards.

[0197] The cooling unit in the high-purity carbon dioxide gas repurification device of this embodiment operates as follows:

[0198] First, cooling oil is injected into the system, so that both the liquid reservoir 2033 and the cold storage assembly 204 contain cooling oil. When a certain adsorption tower 103 is pressurized, the cooling oil flowing through its surface flows to the outlet self-operated three-way temperature control valve 202. Due to its rising temperature, the high-temperature cooling oil flows to the plate heat exchanger 2031, and after cooling, it flows into the liquid reservoir 2033. At the same time, the high-temperature cooling oil flowing through the surface of the adsorption tower 103 flows into the pumping self-operated three-way temperature control valve 2053. Due to its high temperature, the two liquid outlets of the pumping self-operated three-way temperature control valve 2053 remain connected. In this way, the first pressure control valve 2054 and the second pressure control valve 2055 are opened, and the first booster delivery pump 2051 and the cold storage assembly 204 are operated, respectively, delivering the cooling oil in the liquid reservoir 2033 and the cold storage assembly 204 to the heat exchange assembly, thereby cooling the adsorption tower 103. When a large amount of cooling oil flows into the liquid storage tank 2033 , it flows into the cold storage assembly 204 through the second one-way valve 2057 .

[0199] When the pressure of a cold storage component 204 is reduced, its surface temperature drops. The low-temperature cooling oil flowing through its surface flows into the outlet self-operated three-way temperature control valve 202, whereupon the cooling oil flows solely into the cold storage component 204. Simultaneously, the low-temperature cooling oil flowing through the surface of the adsorption tower 103 flows into the pumping self-operated three-way temperature control valve 2053. The control end of the second pressure control valve 2055 is connected to the cooling oil in the heat exchange component, causing the second pressure control valve 2055 to open, the first pressure control valve 2054 to close, and the second booster pump 2052 to operate, directing the cooling oil from the cold storage component 204 into the heat exchange component, thereby continuously cooling the cooling oil. The cooled cooling oil can then be used to cool the adsorption tower 103 as it heats up.

[0200] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all be included in the scope of the claims of the present invention.

Claims

1. A high-purity carbon dioxide gas repurification device, characterized in that: It includes a purification and separation unit and a cooling unit; The purification and separation unit comprises: Gas source tank; The first booster pump has an air inlet connected to the air source pipe through a main valve; Three adsorption towers with adsorbent inside; Gas storage unit; Three gas outlet control units connect the three adsorption tower gas storage units in series to form a purification line; the three gas outlet control units are also connected to the gas source tank and the gas storage unit respectively; the gas outlet of the first booster pump is connected to the inside of the adsorption tower at the source of the purification line; Three space replacement components are respectively arranged inside the adsorption tower; Three filling control components are connected to the space replacement components inside the three adsorption towers respectively; A third booster pump, the air inlet of which is connected to the return air valves of the three air outlet control units respectively, and the other end of which is connected to the air source tank; a membrane separation device connected to the gas storage unit; a solvent absorption device connected to the membrane separation device; The cooling unit comprises: Three heat exchange components are respectively wrapped around the outer surfaces of the three adsorption towers to exchange heat with the surfaces of the adsorption towers; Three self-operated three-way temperature control valves with liquid inlets connected to the bottoms of the three heat exchange components, hot liquid outlets connected to the heat exchange components, and cold liquid outlets connected to the cold storage components; Three pumping components, the liquid inlet ends of which are connected to the cold storage component and the heat exchange component respectively, and the liquid outlet ends of which are connected to the tops of the three heat exchange components; The coolant inside the heat exchange component, heat transfer component, cold storage component, liquid outlet self-operated three-way temperature control valve and pumping component is an incompressible cooling liquid.

2. The high-purity carbon dioxide gas re-purification device according to claim 1, characterized in that: The gas outlet control unit comprises: The exhaust valve has one end connected to the interior of the adsorption tower and the other end connected to the outside atmosphere; The return air valve has one end connected to the interior of the adsorption tower and the other end connected to the interior of the gas source tank; A gas delivery valve, one end of which is connected to the interior of the adsorption tower; A flushing valve, one end of which is connected to the gas storage unit and the other end of which is connected to the interior of the upstream adjacent adsorption tower; A second booster pump, the air inlet end of which is connected to the other end of the air delivery valve, and the other end of which is connected to the downstream adsorption tower or gas storage unit; The output bus has one end connected to the interior of the adsorption tower, and the other end connected to the exhaust valve, return air valve, and gas transmission valve; a concentration sensor for detecting carbon dioxide concentration, connected to the output bus; The gas outlet control unit between the two adsorption towers downstream of the purification line also includes a backflush valve, one end of which is connected to the output end of the second booster pump, and the other end is connected to the interior of the previous adsorption tower of the upstream adsorption tower.

3. The high-purity carbon dioxide gas re-purification device according to claim 1, characterized in that: The space replacement component includes: A fixed plate is arranged at the upper part of the adsorption tower; The elastically deformable airbag is fixed on the fixed plate to form a closed space with the fixed plate; A vent pipe, one end of which passes through the adsorption tower and the fixed plate and is connected to the interior of the air bag, and the other end of which is connected to a filling control assembly; a drawstring, one end of which is connected to the inner surface of the bottom of the airbag; The lifting bucket is boxed with an opening facing upward, and the outer surface of the bottom is connected to the other end of the pull rope; the side wall of the lifting bucket is provided with a plurality of lower air inlet holes; The lower end of the elastically deformable pulling cylinder is seamlessly connected to the opening of the lifting bucket, and the outer surface of the pulling cylinder is provided with a plurality of fully concave deformation guide grooves; The fixed cylinder is box-shaped with an opening facing downward. The opening is seamlessly connected to the upper end of the pulling cylinder, and the top outer surface is fixed to the fixed plate. The side wall of the fixed cylinder is provided with a plurality of upper air inlet holes; the ventilation pipe passes through the adsorption tower, the fixed plate and the fixed cylinder in sequence and is connected to the inside of the pulling cylinder.

4. The high-purity carbon dioxide gas re-purification device according to claim 3, characterized in that: The filling control assembly includes: A medium source tank, wherein the medium source tank contains compressible gas; a fourth booster pump with a one-way valve, the inlet end of which is connected to the interior of the medium source tank, and the outlet end of which is connected to the vent pipe of the corresponding space replacement component; a pressure relief valve, one end of which is connected to the vent pipe of the space displacement assembly; The outlet ends of the fourth boost pumps of the three filling control assemblies are connected in sequence through pressure regulating valves.

5. The high-purity carbon dioxide gas re-purification device according to claim 1, characterized in that: The heat exchange assembly comprises: A plurality of heat-conducting fins are divided into a plurality of groups along the axis of the absorbent tank body, the heat-conducting fins in each group are arranged at the same interval; the heat-conducting fins in two adjacent groups are staggered, and a gap is left between the two adjacent groups of fins; the upper and lower end surfaces of the heat-conducting fins are acute-angled end surfaces; the heat-conducting fins are evenly arranged on the outer surface of the absorbent tank body along the axial direction of the absorbent tank body, and the two side end surfaces of the heat-conducting fins are seamlessly connected to the absorbent tank body and the thermal insulation layer respectively; the upper and lower parts of the thermal insulation layer leave an accommodating space from the top and lower ends of the absorbent tank body; The heat insulation layer is wrapped around the outer surface of the absorbent tank and thinly covers the heat-conducting fins. The top of the heat insulation layer is provided with a liquid inlet connected to the pumping component, and the bottom is provided with a liquid outlet connected to the reflux automatic control component.

6. The high-purity carbon dioxide gas re-purification device according to claim 1, characterized in that: The heat exchange component comprises: The first liquid inlet interface of the plate heat exchanger is connected to the hot liquid outlet ends of three liquid outlet self-operated three-way temperature control valves; The refrigeration component has two ends respectively connected to the second liquid inlet interface of the plate heat exchanger and the second liquid outlet interface connected to the liquid inlet interface; The liquid storage tank is connected to the first liquid outlet interface of the plate heat exchanger and the three pumping components.

7. The high-purity carbon dioxide gas re-purification device according to claim 6, characterized in that: The pumping assembly comprises: a first boost delivery pump, the liquid inlet of which is connected to the liquid storage tank, and the liquid outlet of which is connected to the interior of the heat exchange component; a second booster delivery pump, the liquid inlet of which is connected to the cold storage component, and the liquid outlet of which is connected to the interior of the heat exchange component; A pump-operated three-way temperature control valve, the liquid inlet of which is connected to the bottom of the heat exchange component; A first pressure control valve is provided between the first booster delivery pump and the heat exchange assembly, the control end of the valve is connected to the cold liquid outlet of the pumping self-operated three-way temperature control valve, and the control end is provided with a first one-way valve connected to the outside; The second pressure control valve is arranged between the second booster delivery pump and the heat exchange component, the control end of which is connected to the hot liquid outlet end of the pumping self-operated three-way temperature control valve, and the control end of which is provided with a first one-way valve connected to the outside; The second one-way valve has two ends connected to the liquid storage tank and the cold storage assembly respectively, and controls the flow of coolant from the liquid storage tank to the cold storage assembly.

8. The high-purity carbon dioxide gas re-purification device according to claim 6, characterized in that: The cooling unit further comprises: coolant container; three pressure pumps, with their liquid inlets connected to the coolant container; Two ends of the three third pressure control valves are respectively connected to the liquid outlets of the three pressure pumps and the tops of the three heat exchange components, and the control ends are connected to the bottoms of the heat exchange components.

9. A method for repurifying high-purity carbon dioxide gas, characterized in that: The following steps are involved: S1. Collect high-purity carbon dioxide gas obtained by other methods into a gas source tank, and inject high-pressure high-purity carbon dioxide gas into the gas outlet unit; S2. Open the main valve, start the first booster pump, and pressurize the gas to be purified and inject it into the first adsorption tower until the pressure meets the adsorption requirements, then close the first booster pump and the main valve; S3, the fourth booster pump connected to the first adsorption tower is operated to inflate the air bag in the adsorption tower, and at the same time, the exhaust valve connected to the first adsorption tower is opened to obtain the concentration sensor value; If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve connected to the first adsorption; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration for reuse, the exhaust valve connected to the first adsorption is closed, the return valve connected to the first adsorption is opened, and the third booster pump is started at the same time; S4. After the airbag is fully expanded, the flushing valve connected to the first adsorption tower is opened, and high-pressure high-purity carbon dioxide is used to flush the first adsorption tower; S5. Real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor; If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve connected to the first adsorption; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration for reuse, the exhaust valve connected to the first adsorption is closed, the return valve connected to the first adsorption is opened, and the third booster pump is started at the same time; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be further adsorbed and purified, close the exhaust valve and the return valve connected to the first adsorption tower, open the gas supply valve connected to the first adsorption tower, and at the same time, start the second booster pump connected to the first adsorption tower to input the gas into the second adsorption tower; S6, after the gas is injected into the second adsorption tower and reaches a predetermined pressure, stop injecting the gas into the second adsorption tower; S7: The fourth booster pump connected to the second adsorption tower starts to inflate the air bag in the adsorption tower. At the same time, the exhaust valve connected to the second adsorption tower is opened to obtain the concentration sensor value. If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through an exhaust valve connected to the second adsorption; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be reused, close the exhaust valve connected to the second adsorption, open the return air valve connected to the second adsorption, and start the third booster pump at the same time; S8. After the airbag is fully expanded, the flushing valve connected to the second adsorption tower is opened, and high-pressure high-purity carbon dioxide is used to flush the second adsorption tower; S9, real-time monitoring of the carbon dioxide concentration of the gas flowing through the concentration sensor; If the carbon dioxide concentration of the gas flowing through the concentration sensor is lower than the minimum concentration that can be reused, the gas is discharged through the exhaust valve connected to the second adsorption; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be reused, close the exhaust valve connected to the second adsorption, open the return air valve connected to the second adsorption, and start the third booster pump at the same time; If the carbon dioxide concentration of the gas flowing through the concentration sensor reaches the minimum concentration that can be further adsorbed and purified, close the exhaust valve and the return valve connected to the second adsorption tower, open the gas supply valve connected to the second adsorption tower, and at the same time, start the second booster pump connected to the second adsorption tower to input the gas into the next adsorption tower; S10, the third adsorption tower operates according to the working steps of the second adsorption tower in steps S6 to S9, and finally injects the purified gas into the gas storage unit; S11, the gas in the gas storage unit enters the membrane separation device to further purify the gas; S12. The gas purified by the membrane separation equipment enters the solvent absorption equipment for further purification to obtain high-concentration carbon dioxide gas that meets national standards.

10. The method for repurifying high-purity carbon dioxide gas according to claim 9, characterized in that: When the second adsorption tower starts to depressurize, when flushing the first adsorption tower, one or both of the backflush valve and the flushing valve connected to the second adsorption tower can be opened to flush the first adsorption tower; When the third adsorption tower starts to reduce pressure, when flushing the second adsorption tower, one or both of the backflush valve and the flush valve connected to the third adsorption tower can be opened to flush the second adsorption tower.

Images