AU2023306185A1 - Carbon dioxide absorption system - Google Patents

Abstract

A carbon dioxide absorption system, comprising: a Venturi tower (10) comprising, in sequence from top to bottom, a contraction section (11), a throat section (12) and a diffusion section (13), the throat section (12) being provided with a Venturi tower packing layer (14); a cooling and dust removal spray system (40), which is used to spray a cooling and dust removal liquid to the Venturi tower packing layer (14); a carbon dioxide absorption tower (20), comprising an absorption tower body (21) and an absorption tower packing layer (23), the top part of the absorption tower body (21) being provided with an absorption tower exhaust pipe (24); a lean liquid spray system (50), which is used to spray a carbon dioxide absorption liquid to the absorption tower packing layer (23); and a communication box body (30), wherein the bottom part of the absorption tower body (21) and the diffusion section (13) communicate by means of the communication box body (30).

Description

CARBON DIOXIDE ABSORPTION SYSTEM CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Chinese Patent Application No. 202221815675.8, titled "CARBON DIOXIDE ABSORPTION SYSTEM," filed with the China National Intellectual Property Administration on July 14, 2022, the entire content of which is incorporated herein by reference.

FIELD D [0002] The present invention relates to the technical field of environmental protection equipment, and more particularly to a carbon dioxide absorption system.

BACKGROUND

[0003] In addition to causing global warming, greenhouse gases such as carbon dioxide cause major impacts such as land water loss, sea level rise, threat to human survival and grain supply. Flue gases discharged by coal-fired power plants contain a large amount of carbon dioxide gas. In the Global Carbon Dioxide Emissions Statistics Report in 2021, it is proposed that coal combustion as a source of carbon dioxide emissions accounts for 40% of the total global emissions increment. Carbon dioxide emissions increment in electric power and heating industry is over 900 million tons, D accounting for 46% of the global increment, and the emissions and the increment are huge. Therefore, the capture and utilization of carbon dioxide in the flue gas discharged by coal-fired power plants has become an urgent issue in the field of environmental protection at present.

[0004] At present, CO 2 capture, utilization and storage technologies have been implemented in pilot-scale and industrialized projects in a plurality of coal-fired power plants in China. Main capture methods include a physical adsorption method, a chemical absorption method, and a membrane reactor method, etc. A method with a widest application range is a carbon dioxide chemical absorption method mainly based on a phase change absorbent. This method uses a carbon dioxide absorber and a regeneration tower as main equipment, and uses a phase change solvent as a spraying liquid to directionally capture and absorb carbon dioxide gas in the flue gas. Capture efficiency may D reach 99% or more.

[0005] However, before the flue gas enters the carbon dioxide absorber, a series of pretreatments, such as desulfurization, denitrification, dust removal and cooling, etc., should be performed on the flue gas, so as to adjust a physical state of the flue gas and avoid the pollution of a carbon dioxide absorption liquid caused by excessive temperature, large dust content and other exhaust gas impurities in the flue gas, thus affecting carbon dioxide capture efficiency. However, in practical engineering applications, there are often many phenomena in pretreatment section, such as too many equipment, large floor space and long transmission section resulting in the loss and leakage of the flue gas and increased energy consumption.

[0006] Therefore, how to reduce floor space and at the same time have functions of cooling and dust removal and carbon dioxide capture is a technical problem that needs to be solved by those skilled in the art at present.

SUMMARY

[0007] In view of this, the object of the present invention is to provide a carbon dioxide absorption system, which has functions of cooling and dust removal and carbon dioxide capture while reducing D floor space.

[0008] In order to achieve the above-mentioned object, the present invention provides following technical solutions.

[0009] A carbon dioxide absorption system includes a Venturi tower, a cooling and dust removal spraying system, a carbon dioxide absorber, a lean liquid spraying system, and a communication box. The Venturi tower includes a contraction section, a throat section and a diffusion section in sequence from top to bottom. The throat section is provided with a Venturi tower packing layer, and the contraction section is configured to receive a desulfurized flue gas introduced by a flue gas induction system. The cooling and dust removal spraying system is configured to spray a cooling and dust removal liquid above the Venturi tower packing layer. The carbon dioxide absorber includes D an absorber body and an absorber packing layer arranged in the absorber body. An absorber exhaust pipe is provided at a top of the absorber body. The lean liquid spraying system is configured to spray a carbon dioxide absorption liquid above the absorber packing layer. A bottom of the absorber body and the diffusion section are communicated via the communication box.

[0010] Optionally, in the carbon dioxide absorption system, the communication box includes a communication box body and a thermally conductive partition arranged in the communication box body. The thermally conductive partition divides the communication box body into a pretreatment tank and a cold rich liquid tank, the pretreatment tank is configured to receive the cooling and dust removal liquid falling from the Venturi tower, and the cold rich liquid tank is configured to receive the carbon dioxide absorption liquid falling from the carbon dioxide absorber. A flue configured to D communicate the bottom of the absorber body and the diffusion section is formed above a liquid surface of the communication box body.

[0011] Optionally, in the carbon dioxide absorption system, the thermally conductive partition is arranged on a bottom wall of the communication box body, and the flue is provided between the thermally conductive partition and a top wall of the communication box body for flue gas circulation.

[0012] Optionally, in the carbon dioxide absorption system, heat exchange fins are provided at a side of the thermally conductive partition facing the pretreatment tank and/or a side of the thermally conductive partition facing the cold rich liquid tank.

[0013] Optionally, in the carbon dioxide absorption system, the cooling and dust removal spraying system includes a cooling and dust removal spray pipe, and a Venturi circulation pump. A first end of the cooling and dust removal spray pipe is in communication with a spray liquid nozzle, and the spray liquid nozzle is arranged in the contraction section to spray the cooling and dust removal liquid above the Venturi tower packing layer. An outlet of the Venturi circulation pump is in communication with a second end of the cooling and dust removal spray pipe, an inlet of the Venturi circulation pump is in communication with a liquid inlet pipe, and the liquid inlet pipe is communicated below the liquid surface of the pretreatment tank. D [0014] Optionally, the carbon dioxide absorption system further includes a liquid replenishing system configured to replenish the cooling and dust removal liquid into the pretreatment tank.

[0015] Optionally, the carbon dioxide absorption system further includes a liquid drainage system, a liquid level sensor, and a temperature sensor. The liquid drainage system is configured to discharge the cooling and dust removal liquid in the pretreatment tank. The liquid level sensor is configured to detect a liquid level in the pretreatment tank. When the liquid level is lower than a first preset liquid level, the liquid replenishing system is turned on. When the liquid level is higher than a second preset liquid level, the liquid drainage system is turned on. The temperature sensor is configured to detect a temperature of the cooling and dust removal liquid in the pretreatment tank. When the temperature exceeds a preset temperature, the liquid drainage system is turned on to discharge the D cooling and dust removal liquid in the pretreatment tank, and the liquid replenishing system is turned on to replenish a new cooling and dust removal liquid into the pretreatment tank.

[0016] Optionally, in the carbon dioxide absorption system, a check valve, a manual ball valve and a rotor flowmeter are connected in series to the cooling and dust removal spray pipe, and an electric ball valve is connected in series to the liquid inlet pipe.

[0017] Optionally, in the carbon dioxide absorption system, the Venturi tower is in communication with a top of the pretreatment tank via a flange.

[0018] Optionally, the carbon dioxide absorption system further includes an absorption liquid conveying unit in communication with the cold rich liquid tank to convey an absorption saturated carbon dioxide absorption liquid in the cold rich liquid tank to an absorbent regeneration unit. D [0019] Optionally, in the carbon dioxide absorption system, the absorption liquid conveying unit includes an absorption liquid conveying pipeline, as well as an absorption liquid conveying pump and a manual ball valve which are connected in series to the absorption liquid conveying pipeline. The manual ball valve is located between the absorption liquid conveying pump and the cold rich liquid tank.

[0020] Optionally, in the carbon dioxide absorption system, the Venturi tower is located at one side of the carbon dioxide absorber and multiple Venturi towers are arranged in parallel.

[0021] Optionally, in the carbon dioxide absorption system, the flue gas induction system includes a Venturi tower air inlet pipe, a flue gas conveying pipeline, and an induced draft fan. The Venturi tower air inlet pipe is in communication with a top of the contraction section of each of the Venturi towers. The flue gas conveying pipeline is configured to convey a desulfurized flue gas. The induced draft fan is connected in series to the flue gas conveying pipeline to introduce a flue gas in the flue gas conveying pipeline into the Venturi tower air inlet pipe.

[0022] Optionally, in the carbon dioxide absorption system, a first end of the Venturi tower air inlet pipe is in communication with the flue gas conveying pipeline, and a second end of the Venturi tower air inlet pipe is blocked by a blind plate. D [0023] Optionally, in the carbon dioxide absorption system, multiple absorber packing layers are arranged at intervals in a height direction of the absorber body, and the lean liquid spraying system is configured to spray the carbon dioxide absorption liquid above a topmost absorber packing layer.

[0024] Optionally, in the carbon dioxide absorption system, an absorber demisting layer is further arranged in the absorber body.

[0025] Optionally, in the carbon dioxide absorption system, the lean liquid spraying system includes a lean liquid spraying pipe, and a lean liquid spraying pump. A first end of the lean liquid spraying pipe is in communication with a lean liquid nozzle, and the lean liquid nozzle is configured to spray the carbon dioxide absorption liquid above the topmost absorber packing layer. The lean liquid spraying pump is connected in series to the lean liquid spraying pipe to drive the carbon D dioxide absorption liquid in the lean liquid spraying pipe to be sprayed out from the lean liquid nozzle.

[0026] Optionally, in the carbon dioxide absorption system, a check valve and a manual ball valve are connected in series to the lean liquid spraying pipe downstream of the lean liquid spraying pump. A manual ball valve is connected in series to the lean liquid spraying pipe upstream of the lean liquid spraying pump.

[0027] According to the carbon dioxide absorption system provided in the present invention, after being subjected to a desulfurization pretreatment, a flue gas from a power plant enters the carbon dioxide absorption system, i.e., enters the contraction section of the Venturi tower. Since the Venturi tower has a Venturi three-section structure of the contraction section, the throat section and the D diffusion section from top to bottom, a flow rate of a dusty and high temperature flue gas entering the Venturi tower is increased. At the same time, the cooling and dust removal spraying system is used to spray the cooling and dust removal liquid above the Venturi tower packing layer from top to bottom. When flowing through the Venturi tower packing layer in the Venturi tower, the dusty and high temperature flue gas and the cooling and dust removal liquid are fully contacted and reacted under the action of the Venturi tower packing layer to generate condensation, and large dusty and high temperature droplets are formed. The large dusty and high temperature droplets fall to the communication box below the Venturi tower. A gas after cooling and dust removal enters the carbon dioxide absorber from the communication box, and performs a sufficient gas and liquid contact reaction with the carbon dioxide absorption liquid sprayed by the lean liquid spraying system in the absorber packing layer from bottom to top. Droplets fall to the communication box with the action of gravity. A captured decarbonization gas is discharged from a top of the absorber body via the absorber exhaust pipe or enters a next treatment refining unit.

[0028] According to the present invention, by arranging the Venturi tower packing layer in the throat section and arranging spraying points of the cooling and dust removal spraying system in the contraction section, a flow rate of the gas (the dusty and high temperature flue gas) may be greatly D controlled by a Venturi structure, so that a relative flow rate of the gas and the liquid (the dusty and high temperature flue gas and the cooling and dust removal liquid) is maximized in the Venturi tower packing layer. The droplets are atomized under a high speed airflow, a gas humidity reaches saturation, and violent collision and condensation occur between dust particles and the droplets, thus achieving an efficient dust removal effect. At the same time, under violent gas and liquid contact, the cooling and dust removal liquid fully exchanges heat with the high temperature flue gas, forming steam to take away heat, so as to achieve a flue gas cooling effect. According to the present invention, a special structure of the Venturi tower is used to replace cooling and dust removal equipment (closed cooling tower, bag filter, etc.) with larger floor space, so that the energy consumption and water consumption of a dust removal and cooling section may be greatly reduced. Moreover, the Venturi D tower is in communication with the carbon dioxide absorber via the communication box, which has functions of both cooling and dust removal and carbon dioxide capture while greatly reducing the floor space.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to illustrate the technical solutions in the present invention or the prior art more clearly, accompanying drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. It is apparent that the accompanying drawings in the following description are some embodiments of the present invention. For those ordinarily skilled in the art, other accompanying drawings may also be obtained from these accompanying drawings without D creative labor.

[0030] FIG. 1 is a schematic diagram of a carbon dioxide absorption system disclosed in an embodiment of the present invention.

[0031] FIG. 2 is a schematic diagram of a Venturi tower system disclosed in an embodiment of the present invention.

[0032] FIG. 3 is a schematic diagram of a communication box system disclosed in an embodiment of the present invention.

[0033] FIG. 4 is a schematic diagram of a carbon dioxide absorber disclosed in an embodiment of the present invention.

[0034] FIG. 5 is a side view of a carbon dioxide absorption system disclosed in an embodiment of the present invention. Reference numerals in FIGS. 1 to 5 are as follows: AVenturi tower 10, a carbon dioxide absorber 20, a communication box 30, a cooling and dust removal spraying system 40, a lean liquid spraying system 50, a flue gas induction system 60, a liquid replenishing system 70, a liquid drainage system 80, an absorption liquid conveying unit 90; A contraction section 11, a throat section 12, a diffusion section 13, a Venturi tower packing D layer 14, an absorber body 21, an absorber demisting layer 22, an absorber packing layer 23, an absorber exhaust pipe 24, a communication box body 31, a thermally conductive partition 32, a cooling and dust removal spray pipe 41, a spray liquid nozzle 42, a rotor flowmeter 43, a Venturi circulation pump 44, a lean liquid spraying pipe 51, a lean liquid spraying pump 52, a lean liquid nozzle 53, a flue gas conveying pipeline 61, an induced draft fan 62, a Venturi tower air inlet pipe 63, a liquid replenishing pipeline 71, a liquid replenishing valve 72, a liquid drainage pipeline 81, a liquid drainage valve 82, an absorption liquid conveying pipeline 91, an absorption liquid conveying pump 92.

DETAILED DESCRIPTION D [0035] The core of the present invention is to provide a carbon dioxide absorption system, which has functions of both cooling and dust removal and carbon dioxide capture while reducing floor space.

[0036] Technical solutions in embodiments of the present invention will be clearly and completely described below with reference to accompanying drawings in the embodiments of the present invention. Apparently, described embodiments are only part of embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative labor shall fall within the protection scope of the present invention.

[0037] As shown in FIG. 1, an embodiment of the present invention discloses a carbon dioxide D absorption system. The carbon dioxide absorption system includes a Venturi tower 10, a cooling and dust removal spraying system 40, a carbon dioxide absorber 20, a lean liquid spraying system 50 and a communication box 30.

[0038] As shown in FIG. 2, the Venturi tower 10 includes a contraction section 11, a throat section 12 and a diffusion section 13 in sequence from top to bottom, and from top to bottom means a positional relationship after the Venturi tower 10 is installed. The contraction section 11 means that a diameter of the contraction section 11 gradually decreases in a flow direction of flue gas. The throat section 12 means that a diameter of the throat section 12 remains unchanged in a flow direction of flue gas. The diffusion section 13 means that a diameter of the diffusion section 13 gradually increases in a flow direction of the flue gas.

[0039] The Venturi tower 10 is configured to perform a cooling and dust removal treatment on a flue gas after being subjected to a desulfurization pretreatment. The throat section 12 is provided with a Venturi tower packing layer 14, and the contraction section 11 is configured to receive a desulfurized flue gas introduced by a flue gas induction system 60. Since the contraction section 11 is located at an uppermost part of the Venturi tower 10, the flue gas flows from top to bottom along the Venturi tower 10. In this embodiment, a SS304 pall ring packing may be used as the Venturi D tower packing layer 14. It should be noted that other packings may be selected as the Venturi tower packing layer 14, as long as it is possible to ensure that a gas and a liquid are evenly mixed.

[0040] The cooling and dust removal spraying system 40 is configured to spray a cooling and dust removal liquid above the Venturi tower packing layer 14. After being subjected to a desulfurization pretreatment, a flue gas from a power plant enters the carbon dioxide absorption system, and first enters the contraction section 11 of the Venturi tower 10. Since the Venturi tower 10 has a Venturi three-section structure of the contraction section 11, the throat section 12 and the diffusion section 13 from top to bottom, a flow rate of a dusty and high temperature flue gas entering the Venturi tower 10 is increased. At the same time, the cooling and dust removal spraying system 40 is configured to spray the cooling and dust removal liquid above the Venturi tower packing layer 14 D from top to bottom. When flowing through the Venturi tower packing layer 14 in the Venturi tower 10, the dusty and high temperature flue gas and the cooling and dust removal liquid are fully contacted and reacted under the action of the Venturi tower packing layer 14 to generate condensation, and larger dusty and high temperature droplets are formed.

[0041] As shown in FIG. 4, the carbon dioxide absorber 20 includes an absorber body 21 and an absorber packing layer 23 arranged in the absorber body 21, and an absorber exhaust pipe 24 is provided at a top of the absorber body 21. In this embodiment, a SS304 pall ring packing may be used as the absorber packing layer 23. It should be noted that other packings may be selected as the absorber packing layer 23, as long as it is possible to ensure that a gas and a liquid are evenly mixed.

[0042] The lean liquid spraying system 50 is configured to spray a carbon dioxide absorption liquid D above the absorber packing layer 23. A gas after cooling and dust removal by the Venturi tower 10 enters the absorber body 21 of the carbon dioxide absorber 20, and performs a sufficient gas and liquid contact reaction with the carbon dioxide absorption liquid sprayed by the lean liquid spraying system 50 in the absorber packing layer 23 from bottom to top. A captured decarbonization gas is discharged from a top of the absorber body 21 via the absorber exhaust pipe 24 or enters a next treatment refining unit.

[0043] A bottom of the absorber body 21 and the diffusion section 13 are communicated via the communication box 30, so that the gas after cooling and dust removal by the Venturi tower 10 may enter the carbon dioxide absorber 20 via the communication box 30. When flowing through the Venturi tower packing layer 14 in the Venturi tower 10, the dusty and high temperature flue gas and the cooling and dust removal liquid are fully contacted and reacted under the action of the Venturi tower packing layer 14 to generate condensation, and larger dusty and high temperature droplets are formed. The communication box 30 may also receive the dusty and high temperature droplets falling freely from the Venturi tower 10. The gas after cooling and dust removal enters the carbon dioxide absorber 20 from the communication box 30, and performs a sufficient gas and liquid contact reaction with the carbon dioxide absorption liquid sprayed by the lean liquid spraying system 50 in D the absorber packing layer 23 from bottom to top. Droplets fall to the communication box 30 with the action of gravity.

[0044] According to the present invention, by arranging the Venturi tower packing layer 14 in the throat section 12 and arranging spraying points of the cooling and dust removal spraying system in the contraction section 11, a flow rate of the gas (the dusty and high temperature flue gas) may be greatly controlled by a Venturi structure, so that a relative flow rate of the gas and the liquid (the dusty and high temperature flue gas and the cooling and dust removal liquid) is maximized in the Venturi tower packing layer 14. The droplets are atomized under a high speed airflow, a gas humidity reaches saturation, and violent collision and condensation occur between dust particles and the droplets, thus achieving an efficient dust removal effect. At the same time, under violent gas and D liquid contact, the cooling and dust removal liquid fully exchanges heat with the high temperature flue gas, forming steam to take away heat, so as to achieve a flue gas cooling effect. According to the present invention, a special structure of the Venturi tower 10 is used to replace cooling and dust removal equipment (closed cooling tower, bag filter, etc.) with larger floor space, so that the energy consumption and water consumption of a dust removal and cooling section may be greatly reduced. Moreover, the Venturi tower 10 is in communication with the carbon dioxide absorber 20 via the communication box 30, which has functions of both cooling and dust removal and carbon dioxide capture while greatly reducing the floor space.

[0045] As shown in FIG. 3, in a specific embodiment of the present invention, the communication box 30 includes a communication box body 31 and a thermally conductive partition 32 arranged in D the communication box body 31. The thermally conductive partition 32 is a partition having heat conductive capability, so that both sides of the thermally conductive partition 32 may sufficiently exchange heat. The thermally conductive partition 32 is arranged on a bottom wall of the communication box body 31, and a flue is provided between the thermally conductive partition 32 and a top wall of the communication box body 31 for flue gas circulation.

[0046] The thermally conductive partition 32 divides the communication box body 31 into a pretreatment tank and a cold rich liquid tank. The pretreatment tank is configured to receive the cooling and dust removal liquid falling from the Venturi tower 10, and the cold rich liquid tank is configured to receive the carbon dioxide absorption liquid falling from the carbon dioxide absorber 20. In this embodiment, the communication box body 31 is divided into the pretreatment tank and the cold rich liquid tank by the thermally conductive partition 32. The pretreatment tank and the cold rich liquid tank is configured to receive liquids falling from the Venturi tower 10 and the carbon dioxide absorber 20, respectively. Therefore, the liquids in the pretreatment tank and the cold rich liquid tank are not mixed, so that the liquids may be recycled.

[0047] A flue configured to communicate the bottom of the absorber body 21 and the diffusion section 13 is formed above a liquid surface of the communication box body 31. That is, it is necessary D to ensure that there is a space between a liquid surface of the communication box body 31 and a top wall of the communication box body 31, so that the gas after cooling and dust removal by the Venturi tower 10 can enter the carbon dioxide absorber 20.

[0048] In this embodiment, the thermally conductive partition 32 is arranged in the communication box body 31, and is configured to conduct pre-heat exchange between the cooling and dust removal liquid in the pretreatment tank below the Venturi tower 10 and a cold rich liquid in the cold rich liquid tank below the carbon dioxide absorber 20. The cold rich liquid is a liquid formed after the carbon dioxide absorption liquid is saturated, and the energy consumption for heating the cold rich liquid during the subsequent regeneration of the carbon dioxide absorption liquid is reduced. At the same time, the cooling and dust removal liquid in the pretreatment tank may be appropriately cooled D to reduce a replacement frequency of the cooling and dust removal liquid. The cooling and dust removal liquid may be a medium such as water, as long as it can reduce a temperature and condense with dust.

[0049] In this embodiment, in order to improve heat exchange efficiency of the thermally conductive partition 32, heat exchange fins are provided at a side ofthe thermally conductive partition 32 facing the pretreatment tank and/or a side of the thermally conductive partition 32 facing the cold rich liquid tank. In this embodiment, by providing heat exchange fins on the thermally conductive partition 32, a heat exchange area of the thermally conductive partition 32 may be increased, so that a temperature of the cold rich liquid in the cold rich liquid tank may be increased, and a temperature of the cooling and dust removal liquid in the pretreatment tank may be reduced. D [0050] As shown in FIG. 2, in this embodiment, the cooling and dust removal spraying system 40 includes a cooling and dust removal spray pipe 41, a Venturi circulation pump 44 and a spray liquid nozzle 42.

[0051] A first end of the cooling and dust removal spray pipe 41 is in communication with the spray liquid nozzle 42, and the spray liquid nozzle 42 is arranged in the contraction section 11 to spray the cooling and dust removal liquid above the Venturi tower packing layer 14. A SS304 spiral nozzle may be selected as the spray liquid nozzle 42, so that the cooling and dust removal liquid may be sprayed spirally after being sprayed, thus improving an atomization degree of the cooling and dust removal liquid and improving mixing efficiency with the high temperature flue gas.

[0052] An outlet of the Venturi circulation pump 44 is in communication with a second end of the cooling and dust removal spray pipe 41, an inlet of the Venturi circulation pump 44 is in communication with a liquid inlet pipe, and the liquid inlet pipe is communicated below the liquid surface of the pretreatment tank. Under the power of Venturi circulation pump 44, the cooling and dust removal liquid in the pretreatment tank is pumped out via the liquid inlet pipe, and is sprayed from the spray liquid nozzle 42 to the Venturi tower packing layer 14 via the cooling and dust removal spray pipe 41. D [0053] Further, a check valve, a manual ball valve and a rotor flowmeter 43 may be connected in series to the cooling and dust removal spray pipe 41, and an electric ball valve is connected in series to the liquid inlet pipe. The check valve enables the cooling and dust removal spray pipe 41 in a communication state in a direction from the second end to the first end, and enables the cooling and dust removal spray pipe 41 in a cut-off state in a direction from the first end to the second end. That is, the cooling and dust removal liquid may only flow in a direction from the Venturi circulation pump 44 to the spray liquid nozzle 42, the cooling and dust removal liquid may be prevented from flowing back into the pretreatment tank from the spray liquid nozzle 42.

[0054] An operator may manually cut off a passage of the cooling and dust removal spray pipe 41 via the manual ball valve to control a working state of the spray liquid nozzle 42. The rotor flowmeter D 43 is configured to detect a flow rate of the cooling and dust removal liquid in the cooling and dust removal spray pipe 41, so that a rotating speed of the Venturi circulation pump 44 may be controlled according to the flow rate, and then a flow rate sprayed by the spray liquid nozzle 42 fluctuates within a certain range, so as to avoid the flow rate being too low or too high. The electric ball valve may be automatically controlled and automatically opened by a controller according to needs.

[0055] As shown in FIG. 1, when spraying, the cooling and dust removal liquid exchanges heat with the high temperature flue gas, steam is formed, resulting in the loss of the cooling and dust removal liquid. Therefore, the cooling and dust removal liquid in the pretreatment tank needs to be supplemented regularly. Based on this, an embodiment of the present invention may further include a liquid replenishing system 70 configured to replenish the cooling and dust removal liquid into the D pretreatment tank. According to a volume of the cooling and dust removal liquid in the pretreatment tank, the operator may replenish the cooling and dust removal liquid into the pretreatment tank via the liquid replenishing system 70 when necessary.

[0056] As shown in FIG. 3, the liquid replenishing system 70 may include a liquid replenishing pipeline 71 and a liquid replenishing valve 72 connected in series to the liquid replenishing pipeline 71. A first end of the liquid replenishing pipeline 71 is in communication with the pretreatment tank, specifically may be in communication above the liquid surface of the pretreatment tank, and a second end of the liquid replenishing pipeline 71 is in communication with a water supply pipe. The liquid replenishing pipeline 71 may be opened or cut off via the liquid replenishing valve 72. When the liquid replenishing valve 72 is opened, the cooling and dust removal liquid in the water supply pipe may enter the pretreatment tank via the liquid replenishing pipeline 71. When the liquid replenishing valve 72 is closed, the cooling and dust removal liquid in the water supply pipe is cut off.

[0057] As shown in FIG. 1, since there are many impurities in the cooling and dust removal liquid after the cooling and dust removal liquid exchanges heat with the high temperature flue gas for several times, the cooling and dust removal liquid needs to be replaced. Based on this, the carbon dioxide absorption system disclosed in embodiments of the present invention may further include a D liquid drainage system 80 and a liquid level sensor.

[0058] The liquid drainage system 80 is configured to discharge the cooling and dust removal liquid in the pretreatment tank. The operator may discharge the cooling and dust removal liquid in the pretreatment tank via the liquid drainage system 80 when necessary according to a volume of the cooling and dust removal liquid in the pretreatment tank and an impurity content of the cooling and dust removal liquid.

[0059] As shown in FIG. 3, the liquid drainage system 80 may include a liquid drainage pipeline 81 and a liquid drainage valve 82 connected in series to the liquid drainage pipeline 81. A first end of the liquid drainage pipeline 81 is in communication with the pretreatment tank, specifically may be in communication with a bottom of the pretreatment tank, and a second end of the liquid drainage D pipeline 81 is in communication with a drain pipe. The liquid drainage pipeline 81 may be opened or cut off via the liquid drainage valve 82. When the liquid drainage valve 82 is opened, the cooling and dust removal liquid in the pretreatment tank may be discharged into the drain pipe via the liquid drainage pipeline 81 and finally discharged to a corresponding position via the drain pipe. When the liquid drainage valve 82 is closed, the cooling and dust removal liquid in the pretreatment tank is cut off.

[0060] The liquid level sensor is configured to detect a liquid level in the pretreatment tank. When the liquid level is lower than a first preset liquid level, the liquid replenishing system 70 is turned on. When the liquid level is higher than a second preset liquid level, the liquid drainage system 80 is turned on. Therefore, the cooling and dust removal liquid in the pretreatment tank is always D between the first preset liquid level and the second preset liquid level.

[0061] The pretreatment tank may also be provided with a temperature sensor. The temperature sensor is configured to detect a temperature of the cooling and dust removal liquid in the pretreatment tank. When the temperature exceeds a preset temperature, the liquid drainage system 80 is turned on to discharge the cooling and dust removal liquid in the pretreatment tank, and the liquid replenishing system 70 is turned on to replenish a new cooling and dust removal liquid into the pretreatment tank, thus reducing the temperature of the cooling and dust removal liquid in the pretreatment tank.

[0062] Specifically, the Venturi tower 10 maybe in communication with atop of the pretreatment tank via a flange, so as to facilitate assembly of the Venturi tower 10 and the communication box 30.

[0063] As shown in FIG. 1, in a specific embodiment of the present invention, the carbon dioxide absorption system may further include an absorption liquid conveying unit 90 in communication with the cold rich liquid tank to convey an absorption saturated carbon dioxide absorption liquid in the cold rich liquid tank to an absorbent regeneration unit. After repeated use, the carbon dioxide absorption liquid in the cold rich liquid tank needs to be regenerated. The absorption liquid conveying unit 90 conveys the absorption saturated carbon dioxide absorption liquid in the cold rich D liquid tank to the absorbent regeneration unit for regeneration, and the absorption saturated carbon dioxide absorption liquid is regenerated and then used again.

[0064] As shown in FIG. 3, the absorption liquid conveying unit 90 may include an absorption liquid conveying pipeline 91, as well as an absorption liquid conveying pump 92 and a manual ball valve which are connected in series to the absorption liquid conveying pipeline 91. The manual ball valve is located between the absorption liquid conveying pump 92 and the cold rich liquid tank. The absorption liquid conveying pipeline 91 may be opened or closed by the manual ball valve. When the manual ball valve is opened, the carbon dioxide absorption liquid in the cold rich liquid tank, under the action of the absorption liquid conveying pump 92, may be pumped into the absorbent regeneration unit via the absorption liquid conveying pipeline 91. When the manual ball valve is D closed, the absorption liquid conveying pipeline 91 is cut off.

[0065] As shown in FIG. 5, in order to improve cooling and dust removal efficiency, in this embodiment, the Venturi towers 10 are located at one side of the carbon dioxide absorber 20 and multiple Venturi towers 10 are arranged in parallel. FIG. 5 shows a solution of three Venturi towers 10. It should be noted that the specific number of Venturi towers 10 may be set according to a treatment amount of the flue gas.

[0066] As shown in FIG. 2, the flue gas induction system 60 further includes a Venturi tower air inlet pipe 63, a flue gas conveying pipeline 61 and an induced draft fan 62. The Venturi tower air inlet pipe 63 is in communication with a top of the contraction section 11 of each of the Venturi towers 10, so that each of the Venturi towers 10 is in a parallel state. D [0067] The flue gas conveying pipeline 61 is configured to convey a desulfurized flue gas, and the induced draft fan 62 is connected in series to the flue gas conveying pipeline 61 to introduce the flue gas in the flue gas conveying pipeline 61 into the Venturi tower air inlet pipe 63. The flue gas, under the action of the induced draft fan 62, is sent to the Venturi tower air inlet pipe 63 via the flue gas conveying pipeline 61, and then is sequentially sent to each of the Venturi towers 10 for processing.

[0068] Further, a first end of the Venturi tower air inlet pipe 63 is in communication with the flue gas conveying pipeline 61, and a second end of the Venturi tower air inlet pipe 63 is blocked by a blind plate, so as to avoid delayed leakage. Alternatively, two ends of the Venturi tower air inlet pipe 63 may be blocked, and the flue gas conveying pipeline 61 may be communicated with an area between the two ends of the Venturi tower air inlet pipe 63.

[0069] In this embodiment, multiple absorber packing layers 23 are arranged at intervals in a height direction of the absorber body 21, and the lean liquid spraying system 50 is configured to spray the carbon dioxide absorption liquid above a topmost absorber packing layer 23, so as to improve carbon dioxide absorption efficiency. An absorber demisting layer 22 is further arranged in the absorber body 21. The absorber demisting layer 22 is located above the absorber packing layer 23. After being demisted by the absorber demisting layer 22, a decarbonized gas is discharged via the absorber D exhaust pipe 24. The absorber demisting layer 22 may be a SS304 baffle.

[0070] As shown in FIG. 4, in a specific embodiment of the present invention, the lean liquid spraying system 50 includes a lean liquid spraying pipe 51, a lean liquid nozzle 53 and a lean liquid spraying pump 52. A first end of the lean liquid spraying pipe 51 is in communication with the lean liquid nozzle 53, and the lean liquid nozzle 53 is configured to spray the carbon dioxide absorption liquid above the topmost absorber packing layer 23. A SS304 spiral nozzle may be selected as the lean liquid nozzle 53, so that the carbon dioxide absorption liquid may be sprayed spirally after being sprayed, thus improving an atomization degree of the carbon dioxide absorption liquid and improving reaction efficiency with the high temperature flue gas.

[0071] The lean liquid spraying pump 52 is connected in series to the lean liquid spraying pipe 51 D to drive the carbon dioxide absorption liquid in the lean liquid spraying pipe 51 to be sprayed out from the lean liquid nozzle 53. Under the power of the lean liquid spraying pump 52, the carbon dioxide absorption liquid is sprayed to the absorber packing layer 23 by the lean liquid spraying pump 52 via lean liquid spraying pipe 51.

[0072] Further, a check valve and a manual ball valve are connected in series to the lean liquid spraying pipe 51 downstream of the lean liquid spraying pump 52. A manual ball valve is connected in series to the lean liquid spraying pipe 51 upstream of the lean liquid spraying pump 52. The check valve enables the lean liquid spraying pipe 51 in a communication state in a direction from the second end to the first end, and enables the lean liquid spraying pipe 51 in a cut-off state in a direction from the first end to the second end. That is, the carbon dioxide absorption liquid may only flow in D a direction from the lean liquid spraying pump 52 to the lean liquid nozzle 53, the carbon dioxide absorption liquid may be prevented from flowing backwards. The operator may manually cut off a passage of the lean liquid spraying pipe 51 upstream of the lean liquid spraying pump 52 and a passage of the lean liquid spraying pipe 51 downstream of the lean liquid spraying pump 52 via the manual ball valve, so as to control a working state of the lean liquid nozzle 53.

[0073] It should be noted that the embodiments in this specification are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and same and similar parts between the embodiments refer to each other.

[0074] As shown in the present application and claims, words "a," "an," and/or "the" do not specifically refer to singular forms, and may also include the plural forms, unless otherwise expressly. Generally speaking, terms "including" and "comprising" only imply the inclusion of clearly identified steps and elements, and these steps and elements do not constitute an exclusive list, and a method or equipment may also include other steps or elements. An element defined by a sentence "including a..." does not exclude that there are other identical elements in a process, a method, a commodity or equipment including the element.

[0075] In the description of the embodiments of the present application, "/"means or, unless D otherwise specified. For example, A/B may mean A or B. "And/or" herein is only a relationship that describes associated objects, indicating that there may be three relationships. For example, A and/or B may indicate that A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality of' means two or more than two.

[0076] Terms such as "first" and "second" are used below for purposes of description and are not intended to indicate or imply relative importance or to imply the number of indicated technical features. Thus, the feature defined with "first" and "second" may explicitly or implicitly include one or more of such a feature.

[0077] The principle and implementation of the present invention are elaborated herein by using D specific embodiments, and the description of the above embodiments is only used to help understand the core idea of the present invention. It should be noted that, for those of ordinary skill in the art, several improvements and modifications may be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims (18)

WHAT IS CLAIMED IS:

1. A carbon dioxide absorption system, comprising: a Venturi tower (10) comprising a contraction section (11), a throat section (12) and a diffusion section (13) in sequence from top to bottom, wherein the throat section (12) is provided with a Venturi tower packing layer (14), and the contraction section (11) is configured to receive a desulfurized flue gas introduced by a flue gas induction system (60); a cooling and dust removal spraying system (40) configured to spray a cooling and dust removal liquid above the Venturi tower packing layer (14); a carbon dioxide absorber (20) comprising an absorber body (21) and an absorber packing layer D (23) arranged in the absorber body (21), wherein an absorber exhaust pipe (24) is provided at a top of the absorber body (21); a lean liquid spraying system (50) configured to spray a carbon dioxide absorption liquid above the absorber packing layer (23); and a communication box (30), wherein a bottom of the absorber body (21) and the diffusion section (13) are communicated via the communication box (30).

2. The carbon dioxide absorption system of claim 1, wherein the communication box (30) comprises a communication box body (31) and a thermally conductive partition (32) arranged in the communication box body (31); wherein the thermally conductive partition (32) divides the communication box body (31) into D a pretreatment tank and a cold rich liquid tank, the pretreatment tank is configured to receive the cooling and dust removal liquid falling from the Venturi tower (10), and the cold rich liquid tank is configured to receive the carbon dioxide absorption liquid falling from the carbon dioxide absorber (20); wherein a flue configured to communicate the bottom of the absorber body (21) and the diffusion section (13) is formed above a liquid surface of the communication box body (31).

3. The carbon dioxide absorption system of claim 2, wherein the thermally conductive partition (32) is arranged on a bottom wall of the communication box body (31), and the flue is provided between the thermally conductive partition (32) and a top wall of the communication box body (31) for flue gas circulation. D

4. The carbon dioxide absorption system of claim 2, wherein heat exchange fins are provided at a side of the thermally conductive partition (32) facing the pretreatment tank and/or a side of the thermally conductive partition (32) facing the cold rich liquid tank.

5. The carbon dioxide absorption system of claim 2, wherein the cooling and dust removal spraying system (40) comprises: a cooling and dust removal spray pipe (41), wherein a first end of the cooling and dust removal spray pipe (41) is in communication with a spray liquid nozzle (42), and the spray liquid nozzle (42) is arranged in the contraction section (11) to spray the cooling and dust removal liquid above the Venturi tower packing layer (14); and a Venturi circulation pump (44), wherein an outlet of the Venturi circulation pump (44) is in communication with a second end of the cooling and dust removal spray pipe (41), an inlet of the Venturi circulation pump (44) is in communication with a liquid inlet pipe, and the liquid inlet pipe is communicated below the liquid surface of the pretreatment tank.

6. The carbon dioxide absorption system of claim 5, further comprising a liquid replenishing system (70) configured to replenish the cooling and dust removal liquid into the pretreatment tank. D

7. The carbon dioxide absorption system of claim 6, further comprising: a liquid drainage system (80) configured to discharge the cooling and dust removal liquid in the pretreatment tank; a liquid level sensor configured to detect a liquid level in the pretreatment tank, wherein when the liquid level is lower than a first preset liquid level, the liquid replenishing system (70) is turned on; when the liquid level is higher than a second preset liquid level, the liquid drainage system (80) is turned on; and a temperature sensor configured to detect a temperature of the cooling and dust removal liquid in the pretreatment tank, wherein when the temperature exceeds a preset temperature, the liquid drainage system (80) is turned on to discharge the cooling and dust removal liquid in the D pretreatment tank, and the liquid replenishing system (70) is turned on to replenish a new cooling and dust removal liquid into the pretreatment tank.

8. The carbon dioxide absorption system of claim 5, wherein a check valve, a manual ball valve and a rotor flowmeter (43) are connected in series to the cooling and dust removal spray pipe (41), and an electric ball valve is connected in series to the liquid inlet pipe.

9. The carbon dioxide absorption system of claim 2, wherein the Venturi tower (10) is in communication with a top of the pretreatment tank via a flange.

10. The carbon dioxide absorption system of claim 2, further comprising an absorption liquid conveying unit (90) in communication with the cold rich liquid tank to convey an absorption saturated carbon dioxide absorption liquid in the cold rich liquid tank to an absorbent regeneration D unit.

11. The carbon dioxide absorption system of claim 10, wherein the absorption liquid conveying unit (90) comprises an absorption liquid conveying pipeline (91), as well as an absorption liquid conveying pump (92) and a manual ball valve which are connected in series to the absorption liquid conveying pipeline (91), wherein the manual ball valve is located between the absorption liquid conveying pump (92) and the cold rich liquid tank.

12. The carbon dioxide absorption system of any one of claims 1 to 11, wherein the Venturi tower (10) is located at one side of the carbon dioxide absorber (20) and multiple Venturi towers (10) are arranged in parallel.

13. The carbon dioxide absorption system of claim 12, wherein the flue gas induction system (60) comprises: a Venturi tower air inlet pipe (63) in communication with a top of the contraction section (11) of each of the Venturi towers (10); a flue gas conveying pipeline (61) configured to convey a desulfurized flue gas; and an induced draft fan (62) connected in series to the flue gas conveying pipeline (61) to introduce a flue gas in the flue gas conveying pipeline (61) into the Venturi tower air inlet pipe (63). D

14. The carbon dioxide absorption system of claim 13, wherein a first end of the Venturi tower air inlet pipe (63) is in communication with the flue gas conveying pipeline (61), and a second end of the Venturi tower air inlet pipe (63) is blocked by a blind plate.

15. The carbon dioxide absorption system of any one of claims 1 to 11, wherein multiple absorber packing layers (23) are arranged at intervals in a height direction of the absorber body (21), and the lean liquid spraying system (50) is configured to spray the carbon dioxide absorption liquid above a topmost absorber packing layer (23).

16. The carbon dioxide absorption system of claim 15, wherein an absorber demisting layer (22) is further arranged in the absorber body (21).

17. The carbon dioxide absorption system of claim 15, wherein the lean liquid spraying system D (50) comprises: a lean liquid spraying pipe (51), wherein a first end of the lean liquid spraying pipe (51) is in communication with a lean liquid nozzle (53), and the lean liquid nozzle (53) is configured to spray the carbon dioxide absorption liquid above the topmost absorber packing layer (23); and a lean liquid spraying pump (52) connected in series to the lean liquid spraying pipe (51) to drive the carbon dioxide absorption liquid in the lean liquid spraying pipe (51) to be sprayed out from the lean liquid nozzle (53).

18. The carbon dioxide absorption system of claim 17, wherein a check valve and a manual ball valve are connected in series to the lean liquid spraying pipe (51) downstream of the lean liquid spraying pump (52); and D a manual ball valve is connected in series to the lean liquid spraying pipe (51) upstream of the lean liquid spraying pump (52).