CN219701524U - Carbon dioxide recovery system - Google Patents

Abstract

The utility model discloses a carbon dioxide recovery system which comprises an absorption tower, a regeneration tower and a cleaning unit, wherein a rich liquid outlet at the bottom of the absorption tower is communicated with a liquid inlet of the regeneration tower, a lean liquid outlet of the regeneration tower is communicated with a lean liquid inlet at the upper part of the absorption tower, the cleaning unit comprises a cleaning tank, a water return tank, a cleaning pipe and a water return pipe, liquid outlets of the cleaning tank and the water return tank are communicated with the cleaning pipe, liquid inlets of the cleaning tank and the water return tank are communicated with the water return pipe, a cleaning pump is arranged on the cleaning pipe, the cleaning pipe is communicated with the top of the absorption tower through a first cleaning branch pipe, the rich liquid outlet at the bottom of the absorption tower is communicated with the water return pipe through a first water return branch pipe, the cleaning pipe is communicated with the top of the regeneration tower through a second cleaning branch pipe, and the bottom outlet of the regeneration tower is communicated with the water return pipe through a second water return branch pipe. According to the utility model, the cleaning unit is arranged to periodically perform online circulation cleaning on the absorption tower and the regeneration tower, so that the cleaning efficiency is effective, the scaling blockage inside the absorption tower and the regeneration tower is avoided, and the recovery efficiency of carbon dioxide is improved.

Description

Carbon dioxide recovery system

Technical Field

The utility model relates to the technical field of carbon recovery, in particular to a carbon dioxide recovery system.

Background

Carbon dioxide is a major gas forming a greenhouse effect, and a series of problems such as climate warming, glacier melting, sea level elevation and the like caused by excessive emission have seriously affected the production and life of people, and carbon dioxide recovery has been attracting more and more attention as an effective countermeasure against global warming problems on a global scale; however, the conventional carbon dioxide recovery device cannot be cleaned effectively in time, and thus the inside of the absorption tower and the regeneration tower is easily blocked, which affects the recovery efficiency of carbon dioxide.

In chinese patent application CN115461127a, a carbon dioxide recovery device is disclosed which comprises a separation device for separating carbon dioxide from a gas to be separated (for example, combustion exhaust gas) containing carbon dioxide, wherein the separation device and a carbon dioxide sublimator for sublimating (solidifying) the carbon dioxide separated in the separation device are connected in series from an upstream side of the gas to be separated, a refrigerant circuit using a fluid having cold energy as a refrigerant is connected to the carbon dioxide sublimator, the carbon dioxide is sublimated (solidified) by the refrigerant, and the carbon dioxide sublimator is depressurized to a negative pressure at the time of the sublimation (solidification) of the carbon dioxide, thereby sucking the carbon dioxide separated in the separation device. This patent application can recover carbon dioxide, but cannot effectively clean the carbon dioxide recovery device in time, and the inside pipeline of the device is easily blocked after long-time production, which affects the recovery efficiency of carbon dioxide.

The foregoing background is only for the purpose of facilitating an understanding of the principles and concepts of the utility model and is not necessarily in the prior art to the present application and is not intended to be used as an admission that such background is not entitled to antedate such novelty and creativity by virtue of prior utility model or that it is already disclosed at the date of filing of this application.

Disclosure of Invention

The main object of the present utility model is to overcome the above-mentioned drawbacks of the prior art and to provide a carbon dioxide recovery system.

In order to achieve the above object, the carbon dioxide recovery system provided by the utility model comprises an absorption tower, a regeneration tower and a cleaning unit, wherein a gas inlet at the lower part of the absorption tower is communicated with an air inlet pipe, a gas outlet at the top of the absorption tower is communicated with an air exhaust pipe, a rich liquid outlet at the bottom of the absorption tower is communicated with a liquid inlet of the regeneration tower, a lean liquid outlet of the regeneration tower is communicated with a lean liquid inlet at the upper part of the absorption tower, a gas outlet at the top of the regeneration tower is communicated with a first gas-liquid separator inlet, a gas outlet of the first gas-liquid separator is communicated with a carbon dioxide pipe, the cleaning unit comprises a cleaning tank, a water return tank, a cleaning pipe and a water return pipe, liquid outlets of the cleaning tank and the water return tank are communicated with the cleaning pipe, the cleaning tank and a liquid inlet of the water return tank are communicated with the water return pipe, a cleaning pump is arranged on the cleaning pipe, the cleaning pipe is communicated with the absorption portion through a first cleaning branch pipe, the liquid outlet at the bottom of the absorption tower is communicated with the carbon dioxide pipe through a first branch pipe, and the regeneration tower is communicated with the bottom of the regeneration tower through a second branch pipe. In a period of production, the cleaning liquid stored in the cleaning tank or the cleaning water stored in the cleaning tank is pumped out through the cleaning pump, and enters the absorption tower or the regeneration tower along the cleaning pipe, the first cleaning branch pipe or the second cleaning branch pipe for regular online circulation cleaning, so that the cleaning efficiency is improved, and the influence on the recovery efficiency of carbon dioxide caused by blockage due to carbonate scaling in the absorption tower and the regeneration tower is avoided.

Further, the device also comprises a lean-rich liquid heat exchange device, wherein the lean-rich liquid heat exchange device is communicated between the absorption tower and the regeneration tower, the lean-rich liquid heat exchange device comprises a heat exchange box body and a heat exchange coil pipe, the heat exchange coil pipe is arranged in the heat exchange box body, a lean liquid outlet of the regeneration tower is communicated with an inlet end of the heat exchange coil pipe through a first circulating pipe, an outlet end of the heat exchange coil pipe is communicated with a lean liquid inlet at the upper part of the absorption tower through a second circulating pipe, a rich liquid outlet at the bottom of the absorption tower is communicated with a liquid inlet of the heat exchange box body through a rich liquid pipe, a liquid outlet of the heat exchange box body is communicated with a liquid inlet of the regeneration tower through a semi-lean liquid pipe, a gas-liquid outlet at the top of the heat exchange box body is communicated with an inlet of a second gas-liquid separator, and a gas outlet of the second gas-liquid separator is communicated with a carbon dioxide pipe. By arranging the lean-rich liquid heat exchange device, the rich liquid is preheated by fully utilizing the heat generated by heating of the regeneration tower, so that the energy consumption is reduced, and the carbon dioxide recovery efficiency is further improved.

Further, the cleaning pipe is communicated with the rich liquid pipe through a third cleaning branch pipe, a third backwater branch pipe is communicated with one side, close to the absorption tower, of the second circulating pipe, and the third backwater branch pipe is communicated to the backwater pipe. The third cleaning branch pipe is communicated with the cleaning pipe to circularly clean the pipeline, the lean-rich liquid heat exchange device and other devices, so that the carbon dioxide recovery system is cleaned more thoroughly.

Further, the liquid outlet of the first gas-liquid separator is communicated with the first circulating pipe through a first liquid return pipe. The liquid phase separated by the first gas-liquid separator is led back to the first circulating pipe through the first liquid return pipe and enters the absorption tower again for circulating absorption, so that the loss of absorption liquid is avoided.

Further, the liquid outlet of the second gas-liquid separator is communicated with the semi-lean liquid pipe through a second liquid return pipe. And the liquid phase separated by the second gas-liquid separator is led back to the semi-lean liquid pipe through the second liquid return pipe and enters the regeneration tower again for heating, so that the carbon dioxide recovery efficiency is improved.

Further, a rich liquid pump and a first valve are arranged on the rich liquid pipe, one end of the first backwater branch pipe is communicated with the rich liquid pipe in front of the first valve, a semi-lean liquid pump and a second valve are arranged on the semi-lean liquid pipe, the second backwater pipe is communicated with the semi-lean liquid pipe at the inlet end of the semi-lean liquid pump, a lean liquid pump and a third valve are arranged on the first circulating pipe, a fifteenth valve is arranged on the second circulating pipe, the first backwater pipe is communicated with the first circulating pipe at the inlet end of the lean liquid pump, and a fourth valve is arranged on the carbon dioxide pipe.

Further, a fifth valve is arranged on the first cleaning branch pipe, a sixth valve and a first self-priming pump are arranged on the first water return branch pipe, a seventh valve is arranged on the second cleaning branch pipe, an eighth valve and a second self-priming pump are arranged on the second water return branch pipe, a thirteenth valve is arranged on the third cleaning branch pipe, and a fourteenth valve is arranged on the third water return branch pipe.

Further, a ninth valve is arranged at the position where the liquid inlet of the cleaning tank is communicated with the water return pipe, a tenth valve is arranged at the position where the liquid inlet of the water return tank is communicated with the water return pipe, an eleventh valve is arranged at the position where the liquid outlet of the cleaning tank is communicated with the cleaning pipe, and a twelfth valve is arranged at the position where the liquid outlet of the water return tank is communicated with the cleaning pipe.

Further, the inside of the absorption tower is sequentially provided with a filler, a spray header and a demister from bottom to top, and the spray header is communicated with the lean liquid inlet. Lean liquid entering the absorption tower is uniformly sprayed on the filler through the spray header, and is in gas-liquid contact with the carbon dioxide-containing waste gas in the period of falling along the surface of the filler, so that the carbon dioxide in the waste gas is selectively absorbed to generate rich liquid, and the unabsorbed gas is discharged to the outside of the absorption tower after being defogged by the defogger.

Further, the gas turbine engine further comprises a chimney, and the chimney inlet is communicated with the exhaust pipe. The gas which is not absorbed in the absorption tower is discharged to the outside atmosphere through the exhaust pipe and the chimney, so that the gas is prevented from being discharged on the ground surface and affecting the diffusion of tail gas.

The beneficial effects of the utility model include: by arranging the cleaning unit, the cleaning pump of the cleaning unit pumps the cleaning liquid stored in the cleaning tank or the cleaning water stored in the backwater tank out to enter the absorption tower or the regeneration tower for periodic online circulation cleaning, so that the cleaning efficiency is effectively improved, and the influence on the recovery efficiency of carbon dioxide due to scale blockage in the absorption tower and the regeneration tower is avoided; the carbon dioxide recovery system can more save energy and efficiently recover carbon dioxide.

Drawings

FIG. 1 is a schematic diagram of a carbon dioxide recovery system in an embodiment of the utility model.

Reference numerals: 1 an absorption tower; 101 a gas inlet; 102 a gas outlet; 103 a rich liquid outlet; 104 lean liquid inlet; 105 filler; 106 a spray header; 107 demister; 2 a regeneration tower; 201 a liquid inlet; 202 lean liquid outlet; 203 a gas-liquid outlet; 3, cleaning the unit; 301 cleaning the tank; 3011 a ninth valve; 3012 an eleventh valve; 302 a water return tank; 3021 a tenth valve; 3022 a twelfth valve; 303 cleaning the tube; 3031 cleaning the pump; 3032 a first cleaning branch; 3033 a second cleaning branch; 3034 a third cleaning branch; 3035 a fifth valve; 3036 a seventh valve; 3037 thirteenth valve; 304 return pipe; 3041 first return branch pipe; 3042 a second return branch; 3043 a third return branch; 3044 sixth valve; 3045 first self priming pump; 3046 eighth valve; 3047 a second self priming pump; 3048 fourteenth valve; 4, an air inlet pipe; 5, an exhaust pipe; 6, a first gas-liquid separator; 601 a first return line; 7a carbon dioxide pipe; 8 lean-rich liquid heat exchange device; 801 heat exchange box body; 802 heat exchange coil; 9 a first circulation pipe; 901 lean liquid pump; 902 a third valve; 10 a second circulation tube; 1001 fifteenth valve, 11 rich pipe; 1101 a rich liquid pump; 1102 a first valve; a 12 semi-lean liquid pipe; 1201 semi-lean liquid pump; 1202 a second valve; 13 a second gas-liquid separator; 1301 a second return line; 14 chimney.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved by the embodiments of the present utility model more clear, the present utility model is further described in detail below with reference to the accompanying drawings and the embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. In addition, the connection may be for both the fixing action and the circuit communication action.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are merely for convenience in describing embodiments of the utility model and to simplify the description by referring to the figures, rather than to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the embodiments of the present utility model, the meaning of "plurality" is two or more, unless explicitly defined otherwise.

Referring to fig. 1, the carbon dioxide recovery system disclosed in one embodiment includes an absorption tower 1, a regeneration tower 2 and a cleaning unit 3, wherein a gas inlet 101 at the lower part of the absorption tower 1 is communicated with an air inlet pipe 4, an air blower (not shown) may be arranged on the air inlet pipe 4 for blowing carbon dioxide-containing gas into the inside of the absorption tower 1 to perform gas-liquid convection, carbon dioxide gas is absorbed, a gas outlet 102 at the top of the absorption tower 1 is communicated with an exhaust pipe 5, cleaned tail gas is discharged to the outside atmosphere from the exhaust pipe 5, a rich liquid outlet 103 at the bottom of the absorption tower 1 is communicated with a liquid inlet 201 of the regeneration tower 2, a lean liquid outlet 202 of the regeneration tower 2 is communicated with a lean liquid inlet 104 at the upper part of the absorption tower 1, the absorption liquid regenerated by the regeneration tower 2 is circulated back into the absorption tower 1 to absorb carbon dioxide, a gas outlet 203 at the top of the regeneration tower 2 is communicated with an inlet of a first gas-liquid separator 6, the gas outlet of the first gas-liquid separator 6 is communicated with a carbon dioxide pipe 7, in particular, exhaust gas generated by combustion from a thermal power plant, an iron works, cement plant or the like is discharged from the exhaust gas generated by a thermal treatment furnace, a chemical reaction device and the like to the outside atmosphere, the like is heated and is circulated from the carbon dioxide gas inlet 1 to the absorption tower 1 to the inside the absorption tower 1, carbon dioxide is heated, and is circulated from the lean liquid 1 to the absorption tower 1 to the inside the absorption tower 1, and is heated, and is discharged from the absorption tower 1 to the inside the absorption tower 1 to the absorption tower 1 through the absorption tower 1, and the absorption tower is heated, releasing carbon dioxide and steam, and separating the carbon dioxide and steam by entering a first gas-liquid separator 6 from the top of the regeneration tower 2, wherein the separated carbon dioxide gas is recovered through a carbon dioxide pipe 7, in this embodiment, an amine-series aqueous solution, such as monoethanolamine or diethanolamine, is preferably used as the absorption liquid, and how the regeneration tower 2 is heated is a prior art, and will not be repeated here; the cleaning unit 3 comprises a cleaning tank 301, a water return tank 302, a cleaning pipe 303 and a water return pipe 304, wherein a cleaning agent for cleaning scaling such as carbonate and the like is stored in the cleaning tank 301, cleaning water is stored in the water return pipe 304, liquid outlets of the cleaning tank 301 and the water return tank 302 are communicated with the cleaning pipe 303, liquid inlets of the cleaning tank 301 and the water return tank 302 are communicated with the water return pipe 304, a cleaning pump 3031 is arranged on the cleaning pipe 303, the cleaning pipe 303 is communicated with the top of the absorption tower 1 through a first cleaning branch pipe 3032, a rich liquid outlet 103 at the bottom of the absorption tower 1 is communicated with the water return pipe 304 through a first water return branch pipe 3041, the cleaning pipe 303 is communicated with the top of the regeneration tower 2 through a second water return branch pipe 3042, and each time the cleaning liquid stored in the cleaning tank 301 or the water return tank 302 is discharged through the cleaning pump 3031, the absorption tower 1 and the regeneration tower 2 are periodically circulated on line, cleaning efficiency is improved, the absorption tower 1 and the regeneration tower 2 are prevented from being blocked by the carbon dioxide scaling is prevented, and the carbon dioxide scaling is prevented from being caused.

In one embodiment, the device further comprises a lean-rich liquid heat exchange device 8, the lean-rich liquid heat exchange device 8 is communicated between the absorption tower 1 and the regeneration tower 2, the lean-rich liquid heat exchange device 8 comprises a heat exchange box 801 and a heat exchange coil 802, the heat exchange coil 802 is arranged in the heat exchange box 801, a lean liquid outlet 202 of the regeneration tower 2 is communicated with an inlet end of the heat exchange coil 802 through a first circulating pipe 9, namely a tube side end of the heat exchange coil 802 is communicated, an outlet end of the heat exchange coil 802 is communicated with a lean liquid inlet 104 at the upper part of the absorption tower 1 through a second circulating pipe 10, a rich liquid outlet 103 at the bottom of the absorption tower 1 is communicated with an inlet end of the heat exchange box 801 through a rich liquid pipe 11, a first outlet end of the heat exchange box 801 is communicated with a liquid inlet 201 of the regeneration tower 2 through a semi-lean liquid pipe 12, a second outlet end at the top of the heat exchange box 801 is communicated with an inlet of a second gas-liquid separator 13, and a gas outlet of the second gas-liquid separator 13 is communicated with a carbon dioxide pipe 7. Specifically, the liquid level in the heat exchange box 801 is kept at about 80%, so that the top of the heat exchange coil 802 can generate carbon dioxide and steam mixed gas when preheating the rich liquid, the lean-rich liquid heat exchange device 8 is arranged, heat generated by heating of the regeneration tower 2 is fully utilized to preheat the rich liquid, energy consumption is reduced, part of carbon dioxide and steam can be released in the heat exchange box 801, released carbon dioxide and steam enter the second gas-liquid separator 13 through the second outlet end at the top of the heat exchange box 801 to be separated, separated carbon dioxide gas is recovered through the carbon dioxide pipe 7, and half lean liquid after releasing part of carbon dioxide enters the regeneration tower 2 through the half lean liquid pipe 12 to be continuously heated and released, so that carbon dioxide recovery efficiency is improved.

The cleaning pipe 303 is communicated with the rich liquid pipe 11 through a third cleaning branch pipe 3034, a third backwater branch pipe 3043 is communicated with one side of the second circulating pipe 10, which is close to the absorption tower 1, the third backwater branch pipe 3043 is communicated to the backwater pipe 304, the cleaning pipe 303 is communicated with the cleaning pipe 303 to circularly clean the devices such as a pipeline of the carbon dioxide recovery system, the lean and rich liquid heat exchange device 8 and the like, and cleaning liquid or cleaning water is pumped out by a cleaning pump 3031 during cleaning and then enters the third cleaning branch pipe 3034, the lean and rich liquid heat exchange device 8, the second gas-liquid separator 13 and the first gas-liquid separator 6 for circularly cleaning.

In the preferred embodiment, the liquid outlet of the first gas-liquid separator 6 is communicated with the first circulating pipe 9 through the first liquid return pipe 601, and after the carbon dioxide and steam generated in the regeneration tower 2 are separated by the first gas-liquid separator 6, the liquid phase returns to the first circulating pipe 9 and enters the absorption tower 1 again for circulating absorption, so that the loss of absorption liquid (lean liquid) is reduced.

In the preferred embodiment, the liquid outlet of the second gas-liquid separator 13 is communicated with the semi-lean liquid pipe 12 through the second liquid return pipe 1301, and after the carbon dioxide and steam generated by preheating the rich liquid heat exchange device 8 are separated by the second gas-liquid separator 13, the liquid phase returns to the semi-lean liquid pipe 12 and enters the regeneration tower 2 together with the semi-lean liquid for heating regeneration.

The rich liquid pump 1101 and the first valve 1102 are arranged on the rich liquid pipe 11, the rich liquid pump 1101 is used for pumping the rich liquid in the absorption tower 1 into the heat exchange box 801, one end of the first backwater branch pipe 3041 is communicated with the rich liquid pipe 11 positioned in front of the first valve 1102, when the absorption tower 1 is cleaned, cleaning liquid flows out from the bottom of the absorption tower 1 and enters the first backwater branch pipe 3041 to be circulated back to the cleaning tank 301 or the backwater tank 302, the semi-lean liquid pump 1201 and the second valve 1202 are arranged on the semi-lean liquid pipe 12, the semi-lean liquid pump 1201 is used for pumping the semi-lean liquid after heat exchange in the heat exchange box 801 of the lean-rich liquid heat exchange device 8 into the regeneration tower 2, the second return pipe 1301 is communicated with the semi-lean liquid pipe 12 positioned at the inlet end of the semi-lean liquid pump 1201, so that the liquid in the second gas-liquid separator 13 can smoothly enter the regeneration tower 2, the first circulating pipe 9 is provided with the lean liquid pump 901 and the third valve 902, the lean liquid pump 901 is used for pumping the lean liquid in the regeneration tower 2 into the heat exchange coil 802 of the heat exchange device 8, the first circulating pipe 1 is arranged on the first circulating pipe 9 and enters the first circulating pipe 10 at the inlet end of the first valve 1001, and the first circulating pipe is communicated with the first circulating pipe 601 is arranged at the inlet end of the first valve 1001, and the carbon dioxide can smoothly enter the first valve 601 is arranged at the inlet end of the first valve is communicated with the inlet valve 6, and the first valve is arranged.

The first cleaning branch pipe 3032 is provided with a fifth valve 3035, the first water return branch pipe 3041 is provided with a sixth valve 3044 and a first self-priming pump 3045, the second cleaning branch pipe 3033 is provided with a seventh valve 3036, the second water return branch pipe 3042 is provided with an eighth valve 3046 and a second self-priming pump 3047, the third cleaning branch pipe 3034 is provided with a thirteenth valve 3037, the third water return branch pipe 3043 is provided with a fourteenth valve 3048, the communicating part of the liquid inlet of the cleaning tank 301 and the water return pipe 304 is provided with a ninth valve 3011, the communicating part of the liquid inlet of the water return tank 302 and the water return pipe 304 is provided with a tenth valve 3021, the communicating part of the liquid outlet of the cleaning tank 301 and the cleaning pipe 303 is provided with an eleventh valve 3012, and the communicating part of the liquid outlet of the water return tank 302 and the cleaning pipe 303 is provided with a twelfth valve 3022. When the absorption tower 1 is cleaned, the fifth valve 3035, the sixth valve 3044, the corresponding eleventh valve 3012 or twelfth valve 3022 and the corresponding ninth valve 3011 or tenth valve 3021 are opened, the first valve 1102 is closed, and the first self-priming pump 3045 and the cleaning pump 3031 are started; when the regeneration tower 2 is cleaned, the seventh valve 3036, the eighth valve 3046, the corresponding eleventh valve 3012 or twelfth valve 3022 and the corresponding ninth valve 3011 or tenth valve 3021 are opened, the third valve 902 is closed, and the second self-priming pump 3047 and the cleaning pump 3031 are started; when the pipeline, the lean-rich liquid heat exchange device 8 and other devices are cleaned, the cleaning pump 3031 is started, the thirteenth valve 3037, the fourteenth valve 3048, the corresponding eleventh valve 3012 or twelfth valve 3022 and the corresponding ninth valve 3011 or tenth valve 3021 are opened, and the second valve 1202, the fourth valve 701, the third valve 902 and the fifteenth valve 1001 are closed.

The inside of the absorption tower 1 is sequentially provided with a filler 105, a spray header 106 and a demister 107 from bottom to top, the spray header 106 is communicated with the lean solution inlet 104, the filler 105 is preferably a Raschig ring filler, the absorption liquid is uniformly sprayed on the filler 105 through the spray header 106, and gas-liquid contact is generated with the carbon dioxide-containing waste gas in the period of falling along the surface of the filler 105, so that the carbon dioxide in the waste gas is selectively absorbed to generate rich solution, and the unabsorbed gas is discharged to the outside of the absorption tower 1 after demisted by the demister 107.

In the preferred embodiment, the device further comprises a chimney 14, wherein the inlet of the chimney 14 is communicated with the exhaust pipe 5, and the gas which is not absorbed in the absorption tower 1 is discharged to the external atmosphere through the exhaust pipe 5 and the chimney 14.

The background section of the present utility model may contain background information about the problems or environments of the present utility model and is not necessarily descriptive of the prior art. Accordingly, inclusion in the background section is not an admission of prior art by the applicant.

The foregoing is a further detailed description of the utility model in connection with specific/preferred embodiments, and it is not intended that the utility model be limited to such description. It will be apparent to those skilled in the art that several alternatives or modifications can be made to the described embodiments without departing from the spirit of the utility model, and these alternatives or modifications should be considered to be within the scope of the utility model. In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "preferred embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Those skilled in the art may combine and combine the features of the different embodiments or examples described in this specification and of the different embodiments or examples without contradiction. Although embodiments of the present utility model and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the utility model as defined by the appended claims.

Claims (10)

1. A carbon dioxide recovery system, characterized by: the device comprises an absorption tower, a regeneration tower and a cleaning unit, wherein a gas inlet at the lower part of the absorption tower is communicated with an air inlet pipe, a gas outlet at the top of the absorption tower is communicated with an air exhaust pipe, a rich liquid outlet at the bottom of the absorption tower is communicated with a liquid inlet of the regeneration tower, a lean liquid outlet of the regeneration tower is communicated with a lean liquid inlet at the upper part of the absorption tower, a gas outlet at the top of the regeneration tower is communicated with a first gas-liquid separator inlet, a gas outlet of the first gas-liquid separator is communicated with a carbon dioxide pipe, the cleaning unit comprises a cleaning tank, a water return tank, a cleaning pipe and a water return pipe, liquid outlets of the cleaning tank and the water return tank are communicated with the cleaning pipe, liquid inlets of the cleaning tank and the water return pipe are communicated with the water return pipe, a cleaning pump is arranged on the cleaning pipe, the rich liquid outlet at the bottom of the absorption tower is communicated with the water return pipe through a first cleaning branch pipe, and the cleaning pipe is communicated with the bottom of the regeneration tower through a second cleaning branch pipe, and the regeneration tower is communicated with the water return pipe through a second water return pipe.

2. The carbon dioxide recovery system of claim 1, wherein: the device comprises an absorption tower, a regeneration tower, a heat exchange device, a lean-rich liquid heat exchange device, a semi-lean liquid pipe, a gas-liquid outlet and a carbon dioxide pipe, and is characterized by further comprising the lean-rich liquid heat exchange device, wherein the lean-rich liquid heat exchange device is communicated between the absorption tower and the regeneration tower, the lean-rich liquid heat exchange device comprises a heat exchange box body and a heat exchange coil, the heat exchange coil is arranged in the heat exchange box body, a lean liquid outlet of the regeneration tower is communicated with an inlet end of the heat exchange coil through a first circulating pipe, an outlet end of the heat exchange coil is communicated with a lean liquid inlet at the upper part of the absorption tower through a second circulating pipe, a rich liquid outlet at the bottom of the absorption tower is communicated with a liquid inlet of the heat exchange box body through a rich liquid pipe, a liquid outlet of the heat exchange box body is communicated with a liquid inlet of the regeneration tower through a semi-lean liquid pipe, a gas-liquid outlet at the top of the heat exchange box body is communicated with a second gas-liquid separator inlet, and a gas outlet of the second gas-liquid separator is communicated with the carbon dioxide pipe.

3. The carbon dioxide recovery system of claim 2, wherein: the cleaning pipe is communicated with the rich liquid pipe through a third cleaning branch pipe, a third backwater branch pipe is communicated with one side, close to the absorption tower, of the second circulating pipe, and the third backwater branch pipe is communicated to the backwater pipe.

4. A carbon dioxide recovery system as claimed in claim 3, wherein: the liquid outlet of the first gas-liquid separator is communicated with the first circulating pipe through a first liquid return pipe.

5. The carbon dioxide recovery system of claim 4, wherein: and a liquid outlet of the second gas-liquid separator is communicated with the semi-lean liquid pipe through a second liquid return pipe.

6. The carbon dioxide recovery system of claim 5, wherein: be equipped with rich liquid pump and first valve on the rich liquid pipe, first return water branch pipe one end intercommunication is being located in front of the first valve on the rich liquid pipe, be equipped with half lean liquid pump and second valve on the half lean liquid pipe, the second return liquid pipe intercommunication is being located half lean liquid pump entry end on the half lean liquid pipe, be equipped with lean liquid pump and third valve on the first circulating pipe, be equipped with fifteenth valve on the second circulating pipe, first return liquid pipe intercommunication is being located lean liquid pump entry end on the first circulating pipe, be equipped with the fourth valve on the carbon dioxide pipe.

7. The carbon dioxide recovery system of claim 6, wherein: the first cleaning branch pipe is provided with a fifth valve, the first water return branch pipe is provided with a sixth valve and a first self-priming pump, the second cleaning branch pipe is provided with a seventh valve, the second water return branch pipe is provided with an eighth valve and a second self-priming pump, the third cleaning branch pipe is provided with a thirteenth valve, and the third water return branch pipe is provided with a fourteenth valve.

8. The carbon dioxide recovery system of claim 7, wherein: the liquid inlet of the cleaning tank is provided with a ninth valve at the communication position of the water return pipe, the tenth valve is arranged at the communication position of the liquid inlet of the water return tank and the water return pipe, the eleventh valve is arranged at the communication position of the liquid outlet of the cleaning tank and the cleaning pipe, and the twelfth valve is arranged at the communication position of the liquid outlet of the water return tank and the cleaning pipe.

9. The carbon dioxide recovery system of claim 1, wherein: the inside of the absorption tower is sequentially provided with a filler, a spray header and a demister from bottom to top, and the spray header is communicated with the lean liquid inlet.

10. The carbon dioxide recovery system of claim 1, wherein: the gas-fired boiler further comprises a chimney, and the inlet of the chimney is communicated with the exhaust pipe.