Co2 recovery device

Abstract

This CO2 recovery device includes: a cooling tower into which exhaust gas containing carbon dioxide is introduced and which cools the exhaust gas; and an absorption tower into which the exhaust gas cooled by the cooling tower is introduced and which removes the carbon dioxide from the exhaust gas by bringing the exhaust gas into contact with an absorption liquid. The absorption tower includes a cylindrical absorption tower main body through the inside of which the exhaust gas can flow, and a demister which is disposed inside the absorption tower main body and through which the exhaust gas flow so that mist contained in the exhaust gas can be removed. Further included is a flow rate adjustment unit which sets a flow rate of the exhaust gas flowing through the demister to be within a predetermined range.

Description

CO2 capture equipment

[0001] The present disclosure provides ２ This application claims priority to U.S. Patent Application No. 18 / 359,293, filed July 26, 2023, the contents of which are incorporated herein by reference.

[0002] In recent years, from the perspective of carbon neutrality, the concentration of carbon dioxide in the atmosphere has been attracting attention. ２ CO recovery devices are known. ２ In the recovery system, the absorption liquid is circulated between the regeneration tower and the absorption tower, and CO is extracted from the exhaust gas. ２ Collect.

[0003] For example, CO ２ Patent Document 1 describes a carbon dioxide capture system as a capture device. This carbon dioxide capture system includes an absorption tower that removes carbon dioxide by contacting exhaust gas containing carbon dioxide with an absorption liquid for absorbing carbon dioxide, and a regeneration tower that separates carbon dioxide from the absorption liquid discharged from the absorption tower. Furthermore, this carbon dioxide capture system introduces a first gas having a higher carbon dioxide concentration than the exhaust gas and a second gas having a lower carbon dioxide concentration than the exhaust gas into a gas line to be treated that introduces the exhaust gas into the absorption tower. This allows stable operation to be maintained even if the carbon dioxide concentration or gas flow rate of the gas to be treated changes suddenly.

[0004] Patent No. 6158054

[0005] Incidentally, a demister is disposed in the absorption tower to remove mist components accompanying the exhaust gas before the exhaust gas is released into the atmosphere. The demister has the property that the mist removal performance decreases when the flow rate of the supplied exhaust gas decreases and the flow velocity of the exhaust gas passing through it decreases. However, when CO ２ In the recovery device, the flow rate of the supplied exhaust gas may decrease due to changes in the conditions of the exhaust gas supply source. ２In the recovery system, even if the flow rate of the supplied exhaust gas decreases, it is required to suppress a decrease in the flow rate of the fluid supplied to the demister arranged in the absorption tower.

[0006] The present disclosure provides a CO 2 refrigeration system capable of suppressing a decrease in the flow rate of a fluid supplied to a demister. ２ A recovery device is provided.

[0007] CO according to the present disclosure ２ The recovery device comprises a cooling tower into which exhaust gas containing carbon dioxide is introduced and which cools the exhaust gas, and an absorption tower into which the exhaust gas cooled in the cooling tower is introduced and which brings the exhaust gas into contact with an absorption liquid to remove the carbon dioxide from the exhaust gas, the absorption tower having a cylindrical absorption tower main body through which the exhaust gas can flow, and a demister disposed inside the absorption tower main body and capable of removing mist contained in the exhaust gas as the exhaust gas flows through it, and further comprising a flow rate adjustment unit which adjusts the flow rate of the exhaust gas flowing through the demister within a predetermined range.

[0008] CO of the present disclosure ２ The recovery device can suppress a decrease in the flow rate of the fluid supplied to the demister.

[0009] CO according to the first embodiment ２ 1 is a schematic diagram showing a CO recovery device according to a second embodiment. ２ 1 is a schematic diagram showing a CO recovery device according to a third embodiment. ２ 10 is a schematic diagram showing a CO recovery device according to a fourth embodiment. ２ 10 is a schematic diagram showing a CO recovery device according to a fifth embodiment. ２ Fig. 10 is a schematic diagram showing a recovery device. Fig. 11 is a schematic diagram showing the structure around a demister according to a fifth embodiment. Fig. 12 is a schematic diagram showing the structure around a demister according to a first modified example of the fifth embodiment. Fig. 13 is a schematic diagram showing the structure around a demister according to a second modified example of the fifth embodiment. Fig. 14 is a schematic diagram showing the structure around a demister according to a third modified example of the fifth embodiment.

[0010] Hereinafter, with reference to the accompanying drawings, a CO ２ An embodiment for implementing the recovery device will be described below, but the present disclosure is not limited to this embodiment.

[0011] First embodiment (CO ２ Recovery device) CO ２ The recovery device 10 recovers carbon dioxide (CO ) from the exhaust gas from the exhaust gas generation source 20. ２ ) can be recovered. Examples of the exhaust gas generation source 20 include a boiler, an incinerator, a gas turbine, etc. As shown in FIG. 1, the exhaust gas supplied from the exhaust gas generation source 20 contains a part of CO ２ The remaining part of the exhaust gas is sent to the chimney 30 and discharged into the atmosphere.

[0012] CO of this embodiment ２ The recovery device 10 separates and recovers carbon dioxide contained in the exhaust gas using an absorption liquid, and is capable of supplying the recovered carbon dioxide to another device. ２ The recovery device 10 includes a supply line 1 , a cooling tower 2 , a cooling line 3 , a blower (flow rate increasing section 4 ), an absorption tower 5 , and a flow rate adjusting section 6 .

[0013] The supply line 1 sends a portion of the exhaust gas containing carbon dioxide generated in the exhaust gas generation source 20 to the cooling tower 2. The supply line 1 is a pipe that connects the exhaust gas generation source 20 and the cooling tower 2.

[0014] Exhaust gas containing carbon dioxide is introduced into the cooling tower 2 via a supply line 1. The cooling tower 2 cools the introduced exhaust gas. The exhaust gas cooled in the cooling tower 2 is sent to a cooling line 3. In the cooling tower 2, the exhaust gas having a temperature of 100°C or higher (for example, about 150°C) is cooled to a temperature of 100°C or lower (for example, about 40°C).

[0015] The cooling line 3 sends the exhaust gas cooled in the cooling tower 2 to the absorption tower 5 via a blower 4. The cooling line 3 is a pipe that connects the cooling tower 2 and the absorption tower 5.

[0016] The blower 4 is disposed midway through the cooling line 3. The blower 4 increases the flow rate of the exhaust gas cooled in the cooling tower 2 and supplies the exhaust gas to the absorption tower 5. Specifically, the blower 4 is capable of increasing the pressure of the exhaust gas flowing through the cooling line 3. The blower 4 increases the pressure of the exhaust gas flowing through the cooling line 3, thereby increasing the flow rate of the exhaust gas introduced into the absorption tower 5. The blower 4 is capable of changing the pressure increase rate of the exhaust gas.

[0017] The exhaust gas cooled in the cooling tower 2 is introduced into the absorption tower 5 via the cooling line 3. The absorption tower 5 brings the exhaust gas into contact with an absorbing liquid to remove carbon dioxide from the exhaust gas. An example of the absorbing liquid is an amine solution. The absorption tower 5 sends the exhaust gas from which carbon dioxide has been removed to an exhaust line 9. The absorption tower 5 also sends the absorbing liquid from which carbon dioxide has been recovered to a regeneration tower (not shown). The absorption tower 5 of this embodiment has an absorption tower main body 51 and a demister 52.

[0018] The absorber main body 51 is a cylindrical container extending in the vertical direction Dv. Exhaust gas can flow from below to above in the vertical direction Dv inside the absorber main body 51. An absorption liquid is stored near the bottom of the absorber main body 51. A cooling line 3 is connected to the bottom of the absorber main body 51. An exhaust line 9 is connected to the top of the absorber main body 51.

[0019] The demister 52 is configured to remove mist (small droplets) contained in the exhaust gas by allowing the exhaust gas to flow through it. The demister 52 is disposed inside the absorption tower main body 51. The demister 52 is configured so that the exhaust gas can flow through it after coming into contact with the absorption liquid inside the absorption tower main body 51. The exhaust gas flows through the demister 52 from below to above in the vertical direction Dv. The demister 52 is formed, for example, by stacking multiple layers of mesh woven with thin wires. In this embodiment, multiple layers of the demisters 52 are arranged side by side in the flow direction of the exhaust gas inside the absorption tower 5 (from below to above in the vertical direction Dv).

[0020] The exhaust line 9 exhausts the exhaust gas from which carbon dioxide has been removed in the absorption tower 5 into the atmosphere. The exhaust line 9 is a pipe that connects the absorption tower 5 with the outside.

[0021] The flow rate adjustment unit 6 is configured to keep the flow rate of the fluid flowing through the demister 52 within a predetermined range. In other words, the flow rate adjustment unit 6 is configured to maintain the flow rate of the fluid flowing through the demister 52 at a nearly constant value. The flow rate adjustment unit 6 of the first embodiment controls the flow rate of the flue gas supplied to the absorber 5 at a nearly constant state by utilizing the differential pressure around the demister 52 in the absorber main body 51. In other words, the flow rate adjustment unit 6 adjusts the flow rate of the fluid before being supplied to the demister 52 to a nearly constant state by keeping the flow rate of the flue gas supplied to the absorber 5 at a nearly constant state based on the differential pressure around the demister 52. The flow rate adjustment unit 6 includes a differential pressure acquisition unit 61, an additional supply line 62, a flow rate adjustment valve 63, and a control unit 7.

[0022] The differential pressure acquisition unit 61 acquires information about the differential pressure between the pressure of the exhaust gas before it is supplied to the demister 52 inside the absorber main body 51 and the pressure of the exhaust gas after it has passed through the demister 52 inside the absorber 5. The differential pressure acquisition unit 61 detects the differential pressure between a position upstream and a position downstream of the demister 52 in the flow direction of the exhaust gas inside the absorber 5. The differential pressure acquisition unit 61 of this embodiment has a differential pressure gauge that detects the differential pressure between a position below and a position above the demister 52 in the vertical direction Dv. The differential pressure acquisition unit 61 sends the acquired differential pressure information to the control unit 7.

[0023] The additional supply line 62 is capable of additionally supplying a fluid different from the exhaust gas cooled in the cooling tower 2 to the cooling line 3. The additional supply line 62 further supplies a fluid to the exhaust gas cooled in the cooling tower 2 and before being supplied to the blower 4. The additional supply line 62 is a pipe that connects the exhaust line 9 and the cooling line 3. The additional supply line 62 is connected to the cooling line 3 between the cooling tower 2 and the blower 4. The additional supply line 62 is capable of supplying, as a fluid, a portion of the exhaust gas from which carbon dioxide and mist have been removed in the absorption tower 5 to the cooling line 3.

[0024] The flow rate adjustment valve 63 is capable of adjusting the amount of fluid supplied through the additional supply line 62. The flow rate adjustment valve 63 is disposed midway along the additional supply line 62. The flow rate adjustment valve 63 adjusts the amount of fluid supplied to the cooling line 3 by adjusting the flow rate of the fluid flowing through the additional supply line 62. The opening degree of the flow rate adjustment valve 63 is controlled by the control unit 7. The flow rate adjustment valve 63 may be, for example, an on-off valve whose opening degree is 0% or 100%, or may be an adjustment valve such as a butterfly valve that can be adjusted to an arbitrary opening degree, or a damper with multiple blades.

[0025] The control unit 7 is capable of controlling the opening degree of the flow rate adjustment valve 63. The control unit 7 of the first embodiment is capable of controlling the opening degree of the flow rate adjustment valve 63 based on information on the differential pressure acquired by the differential pressure acquisition unit 61. Specifically, the control unit 7 controls the flow rate adjustment valve 63 to increase the opening degree when the differential pressure acquired by the differential pressure acquisition unit 61 falls below a predetermined specified differential pressure value. The control unit 7 of the first embodiment has an input unit 71, a differential pressure determination unit 72, and a supply amount adjustment unit 73.

[0026] The input unit 71 acquires differential pressure information from the differential pressure acquisition unit 61. The differential pressure determination unit 72 receives the differential pressure information from the input unit 71. The differential pressure determination unit 72 determines whether the differential pressure acquired by the differential pressure acquisition unit 61 is below a predetermined specified differential pressure value. The specified differential pressure value is a predetermined value that is a differential pressure value at which it is considered that the demister 52 cannot fully perform its performance. The differential pressure value at which it is considered that the demister 52 cannot fully perform its performance is a differential pressure value at which the absorber 5 cannot maintain a flue gas flow rate that can ensure the mist removal rate required of the demister 52 due to a low flow rate of flue gas circulating within the absorber main body 51. In other words, the specified differential pressure value is a value at which it is considered that the mist removal rate required of the demister 52 has decreased. If the acquired differential pressure information is below the specified differential pressure value, the differential pressure determination unit 72 sends information to the supply amount adjustment unit 73.

[0027] The supply amount adjustment unit 73 controls the flow rate adjustment valve 63 to adjust the amount of fluid supplied through the additional supply line 62 based on the determination result of the differential pressure determination unit 72. Specifically, the supply amount adjustment unit 73 changes the aperture of the flow rate adjustment valve 63 based on the determination result of the differential pressure determination unit 72. The supply amount adjustment unit 73 acquires information on the determination result from the differential pressure determination unit 72. When the supply amount adjustment unit 73 acquires information on the determination result that the differential pressure information is below a specified differential pressure value, the supply amount adjustment unit 73 widens the aperture of the flow rate adjustment valve 63 to increase the amount of fluid supplied through the additional supply line 62. When the supply amount adjustment unit 73 acquires information on the determination result that the differential pressure information is not below (exceeds) the specified differential pressure value, the supply amount adjustment unit 73 narrows the aperture of the flow rate adjustment valve 63 to decrease the amount of fluid supplied through the additional supply line 62. In this way, the supply amount adjustment unit 73 of this embodiment adjusts the amount of exhaust gas supplied through the additional supply line 62 so that the flow rate of exhaust gas flowing through the cooling line 3 approaches a constant value.

[0028] (Effects) The CO ２ In the recovery device 10, a portion of the flue gas supplied from the flue gas generation source 20 is sent to a cooling tower 2 via a supply line 1. In the cooling tower 2, the flue gas is cooled to 100°C or below. The flue gas cooled in the cooling tower 2 is sent to a blower 4 via a cooling line 3. The blower 4 pressurizes the supplied flue gas. The pressurized flue gas, whose flow rate has increased, is sent to an absorption tower 5 via the cooling line 3. In the absorption tower 5, carbon dioxide is removed from the flue gas by bringing the flue gas into contact with an absorption liquid in an absorption tower main body 51. The flue gas from which carbon dioxide has been removed passes through a demister 52 in the absorption tower main body 51. A constant flow rate of flue gas is supplied to the demister 52, allowing the flue gas to flow in at a flow rate that ensures the demister 52's mist removal function. As a result, the demister 52 removes the mist from the flue gas. Furthermore, within the absorption tower body 51, the pressure difference between the pressure of the exhaust gas before passing through the demister 52 and the pressure of the exhaust gas after passing through the demister 52 becomes larger than a specified pressure difference value. The exhaust gas from which carbon dioxide and mist have been removed by the absorption tower 5 is exhausted into the atmosphere via the exhaust line 9. Furthermore, a portion of the exhaust gas sent to the exhaust line 9 is sent to the additional supply line 62 without being exhausted into the atmosphere.

[0029] Here, if the flow rate of the flue gas supplied to the absorption tower 5 decreases, the flow rate of the flue gas supplied to the demister 52 decreases. However, the flow rate adjustment unit 6 adjusts the flow rate of the fluid flowing through the demister 52 to within a predetermined range. Therefore, the flow rate of the flue gas flowing through the demister 52 is maintained at a nearly constant value. In this way, even if the flow rate of the flue gas supplied from the flue gas generation source 20 decreases, it is possible to continue supplying the fluid at a constant flow rate to the demister 52. Therefore, a decrease in the flow rate of the fluid supplied to the demister 52 can be suppressed.

[0030] Specifically, as the flow rate of the flue gas supplied to the demister 52 decreases, the pressure difference between the pressure of the flue gas before being supplied to the demister 52 and the pressure of the flue gas after passing through the demister 52 decreases within the absorber main body 51. When the pressure difference within the absorber main body 51 falls below a specified pressure difference, the pressure difference determination unit 72, which acquires pressure difference information from the pressure difference acquisition unit 61, sends information to the supply amount adjustment unit 73 that the pressure difference has fallen below the specified pressure difference. This causes the supply amount adjustment unit 73 to control the flow rate adjustment valve 63 to increase its opening. As a result, the flue gas sent to the additional supply line 62 is sent again to the cooling line 3 through the flow rate adjustment valve 63. In other words, not only the flue gas sent from the cooling tower 2 before carbon dioxide removal, but also the flue gas from which carbon dioxide has been removed from the additional supply line 62 is supplied to the cooling line 3. As a result, the flow rate of the flue gas supplied to the absorber 5 through the cooling line 3 is increased. Increasing the flow rate of flue gas supplied to the absorber 5 increases the flow rate of flue gas flowing through the absorber main body 51, and increases the flow rate of flue gas flowing to the demister 52 within the absorber main body 51. This maintains the flow rate of flue gas flowing to the demister 52 within the absorber main body 51 at a nearly constant value. In this way, even if the flow rate of flue gas supplied from the flue gas generation source 20 decreases, it is possible to quickly grasp the decrease in the amount of flue gas supplied to the demister 52 by utilizing information about the differential pressure around the demister 52 within the absorber main body 51, and to continue supplying flue gas at a constant flow rate to the demister 52. Therefore, it is possible to suppress a decrease in the flow rate of the fluid supplied to the demister 52.

[0031] Furthermore, the exhaust gas from which carbon dioxide has been removed in the absorption tower 5 is supplied again to the cooling line 3 via the additional supply line 62 so as to be circulated. In this way, by circulating the exhaust gas from which carbon dioxide has been removed via the additional supply line 62, the exhaust gas can be reused and the flow rate of the fluid supplied to the absorption tower 5 can be increased without separately preparing a new fluid.

[0032] Furthermore, by supplying the flue gas from which carbon dioxide has been removed in the absorber 5 via the additional supply line 62, it is possible to suppress the supply of a cold fluid to the cooling line 3 compared to supplying atmospheric air to the cooling line 3. Furthermore, when supplying a cold fluid, such as when the atmospheric temperature is low, it is necessary to prepare a separate heater and adjust the temperature before supplying the fluid to the cooling line 3. However, by re-supplying the flue gas via the additional supply line 62, it is possible to eliminate the need for temperature adjustment. Furthermore, the oxygen content in the flue gas is less than the oxygen contained in air. Therefore, it is possible to suppress an increase in the oxygen content in the fluid supplied to the absorber 5. As a result, it is possible to suppress oxidative deterioration of the absorption liquid that comes into contact with the flue gas, which is a fluid, in the absorber 5.

[0033] Second Embodiment Next, a CO ２ The recovery device 10A will be described. In the second embodiment described below, components common to the first embodiment are denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. As shown in Fig. 2, the second embodiment differs from the first embodiment in that the flow rate adjusting unit 6A does not utilize the differential pressure within the absorption tower main body 51, but utilizes the pressure of the exhaust gas supplied to the cooling tower 2.

[0034] The flow rate adjusting unit 6A of the second embodiment controls the flow rate of the flue gas supplied to the absorption tower 5 by utilizing the pressure of the flue gas supplied from the flue gas generation source 20 to the cooling tower 2. In other words, the flow rate adjusting unit 6A adjusts the flow rate of the fluid before being supplied to the demister 52 to a nearly constant state by keeping the flow rate of the flue gas supplied to the absorption tower 5 nearly constant based on the pressure of the flue gas supplied to the cooling tower 2. The flow rate adjusting unit 6A has a pressure acquiring unit 65, a flow rate acquiring unit 66, an additional supply line 62, a flow rate adjusting valve 63, and a control unit 7A.

[0035] The pressure acquisition unit 65 acquires information about the pressure of the exhaust gas before it is supplied to the cooling tower 2. The pressure acquisition unit 65 detects the pressure of the exhaust gas in the supply line 1. The pressure acquisition unit 65 of this embodiment has a pressure gauge that detects the pressure at a position in the supply line 1 where the exhaust gas excluding the exhaust gas sent to the chimney 30 flows. The pressure acquisition unit 65 sends the acquired pressure information to the control unit 7A.

[0036] The flow rate acquiring unit 66 acquires information about the flow rate of the exhaust gas cooled in the cooling tower 2 and before being supplied to the blower 4. The flow rate acquiring unit 66 detects the flow rate of the exhaust gas flowing through the cooling line 3 between the cooling tower 2 and the blower 4. The flow rate acquiring unit 66 has a flow meter that detects the flow rate of the exhaust gas at a position closer to the blower 4 than the connection between the cooling line 3 and the additional supply line 62. The flow rate acquiring unit 66 sends the acquired flow rate information to the control unit 7A.

[0037] The control unit 7A is capable of controlling the aperture of the flow rate adjustment valve 63. The control unit 7A of the second embodiment is capable of controlling the aperture of the flow rate adjustment valve 63 based on pressure information acquired by the pressure acquisition unit 65. Specifically, the control unit 7A controls the aperture of the flow rate adjustment valve 63 to increase when the pressure acquired by the pressure acquisition unit 65 falls below a predetermined specified pressure value. Furthermore, the control unit 7A of the second embodiment is capable of controlling the flow rate of exhaust gas in the blower 4 based on flow rate information acquired by the flow rate acquisition unit 66. Specifically, the control unit 7A controls the flow rate of exhaust gas in the blower 4 to increase when the flow rate acquired by the flow rate acquisition unit 66 falls below a predetermined specified flow rate value. The control unit 7A includes an input unit 71A, a pressure determination unit 74, a flow rate determination unit 75, a blower adjustment unit 76, and a supply amount adjustment unit 73A.

[0038] The input unit 71A acquires information about the pressure in the supply line 1 from the pressure acquisition unit 65. The input unit 71A also acquires information about the flow rate in the cooling line 3 from the flow rate acquisition unit 66.

[0039] Pressure information is input to the pressure determination unit 74 from the input unit 71A. The pressure determination unit 74 determines whether the pressure acquired by the pressure acquisition unit 65 is below a predetermined specified pressure value. The specified pressure value is a predetermined value that is a pressure value at which the demister 52 is deemed unable to fully perform its performance. It is necessary to control the value of the pressure acquisition unit 65 to a constant value so as not to cause disturbance to the exhaust gas generation source. If the acquired pressure information is below the specified pressure value, the pressure determination unit 74 sends information to the supply amount adjustment unit 73A.

[0040] The flow rate determination unit 75 receives flow rate information from the input unit 71A. The flow rate determination unit 75 determines whether the flow rate acquired by the flow rate acquisition unit 66 is below a predetermined specified flow rate value. The specified flow rate value is a predetermined value, and is a flow rate value at which the flow rate of the exhaust gas supplied to the absorber 5 by the blower 4 is considered to have decreased. In other words, the specified flow rate value is a value at which it is considered that the flow rate of the exhaust gas required for the absorber 5 cannot be ensured. If the acquired flow rate information is below the specified flow rate value, the flow rate determination unit 75 sends information to the blower adjustment unit 76 and the supply amount adjustment unit 73A.

[0041] The blower adjustment unit 76 adjusts the flow rate of the exhaust gas from the blower 4 based on the determination result of the flow rate determination unit 75. Specifically, the blower adjustment unit 76 acquires information on the determination result from the flow rate determination unit 75. When the blower adjustment unit 76 acquires information on the determination result that the flow rate information is below a specified flow rate value, the blower adjustment unit 76 increases the flow rate of the exhaust gas from the blower 4, thereby significantly increasing the flow velocity of the exhaust gas flowing through the cooling line 3. When the blower adjustment unit 76 acquires information on the determination result that the pressure information is not below (exceeds) the specified pressure value, the blower adjustment unit 76 decreases the flow rate from the blower 4, thereby reducing the rate of increase in the flow velocity of the exhaust gas in the cooling line 3.

[0042] The supply amount adjustment unit 73A adjusts the amount of fluid supplied through the additional supply line 62 by the flow rate adjustment valve 63 based on the determination result of the pressure determination unit 74. When the supply amount adjustment unit 73A acquires information on the determination result that the pressure information has fallen below a specified pressure value, the supply amount adjustment unit 73A increases the opening of the flow rate adjustment valve 63 to increase the amount of fluid supplied through the additional supply line 62. When the supply amount adjustment unit 73A acquires information on the determination result that the pressure information has not fallen below (exceeded) the specified pressure value, the supply amount adjustment unit 73A narrows the opening of the flow rate adjustment valve 63 to decrease the amount of fluid supplied through the additional supply line 62.

[0043] (Effects) CO of the second embodiment ２ In the recovery apparatus 10A, when the flow rate of the exhaust gas supplied from the exhaust gas generation source 20 decreases and the flow rate of the exhaust gas supplied to the absorption tower 5 decreases, the flow rate of the exhaust gas flowing through the cooling line 3 also decreases. Therefore, the flow rate value acquired by the flow rate acquisition unit 66 also decreases. Then, when the flow rate in the cooling line 3 falls below a specified flow rate value, the flow rate determination unit 75, which has acquired flow rate information from the flow rate acquisition unit 66, sends information to the blower adjustment unit 76 and the supply amount adjustment unit 73A that the flow rate has fallen below the specified flow rate value. As a result, the blower adjustment unit 76 increases the flow rate in the blower 4, thereby increasing the rate of increase in the flow velocity of the exhaust gas in the cooling line 3. In this way, the flow velocity of the exhaust gas flowing through the cooling line 3 is adjusted so that the flow rate of the exhaust gas supplied to the absorption tower 5 approaches a constant value.

[0044] Furthermore, if the flow rate of the exhaust gas supplied from the exhaust gas generation source 20 further decreases, the flow rate of the exhaust gas supplied to the absorption tower 5 decreases even if the blower adjustment unit 76 increases the pressure increase rate of the blower 4. That is, not only the flow rate of the exhaust gas flowing through the cooling line 3 but also the flow rate of the exhaust gas flowing through the supply line 1 decreases. As the flow rate of the exhaust gas flowing through the supply line 1 decreases, the pressure value acquired by the pressure acquisition unit 65 also decreases. Then, when the pressure in the supply line 1 falls below a specified pressure value, the pressure determination unit 74, which has acquired pressure information from the pressure acquisition unit 65, sends information to the supply amount adjustment unit 73A that the pressure has fallen below the specified pressure value. Furthermore, as described above, the supply amount adjustment unit 73A also receives information from the flow rate determination unit 75 that the flow rate has fallen below the specified flow rate value. As a result, the supply amount adjustment unit 73A controls the aperture of the flow rate adjustment valve 63 to widen the aperture. Therefore, the exhaust gas sent to the additional supply line 62 is sent again to the cooling line 3 through the flow rate adjustment valve 63. In other words, as in the first embodiment, not only the flue gas from which carbon dioxide has been removed that is sent from the cooling tower 2, but also the flue gas from which carbon dioxide has been removed from the additional supply line 62 is supplied to the cooling line 3. As a result, the flow rate of the flue gas supplied to the absorption tower 5 is increased. By increasing the flow rate of the flue gas supplied to the absorption tower 5, the flow rate of the flue gas flowing to the demister 52 within the absorption tower main body 51 increases. This allows the flow rate of the flue gas flowing to the demister 52 within the absorption tower main body 51 to be maintained at a nearly constant value. In this way, even if the flow rate of the flue gas supplied from the flue gas generation source 20 decreases, it is possible to quickly determine the decrease in the amount of flue gas supplied to the demister 52 by utilizing information about the pressure of the flue gas flowing through the supply line 1, and to continue supplying flue gas at a constant flow rate to the demister 52. Therefore, a decrease in the flow rate of the fluid supplied to the demister 52 can be suppressed.

[0045] Additionally, the second embodiment utilizes not only information on the pressure of the exhaust gas flowing through the supply line 1 but also information on the flow rate of the exhaust gas flowing through the cooling line 3. Therefore, a decrease in the amount of exhaust gas supplied to the demister 52 can be detected quickly and with higher accuracy.

[0046] Furthermore, the flow rate at the blower 4 is adjusted based on information about the flow rate of the exhaust gas flowing through the cooling line 3. This allows for more precise adjustment of the flow rate of the exhaust gas supplied to the absorption tower 5. This therefore makes it possible to continue supplying exhaust gas at a constant flow rate to the demister 52 with high accuracy. This therefore makes it possible to suppress a decrease in the flow rate of the exhaust gas supplied to the demister 52 with higher accuracy.

[0047] Third Embodiment Next, a CO ２ The recovery device 10B will be described. In the third embodiment described below, components common to the first embodiment are denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. As shown in FIG. 3, the third embodiment differs from the first embodiment in that the additional supply line 62B is not connected to the exhaust line 9.

[0048] The flow rate adjusting unit 6B of the third embodiment supplies air as the fluid to the cooling line 3. The flow rate adjusting unit 6B of the third embodiment differs from the first embodiment only in the additional supply line 62B.

[0049] The additional supply line 62B of the third embodiment is connected to the cooling line 3. ２ The additional supply line 62B can supply air (outside air) from the outside of the recovery device 10B as a fluid separate from the exhaust gas. The additional supply line 62B further supplies air from the outside to the exhaust gas cooled in the cooling tower 2 before being supplied to the blower 4. The additional supply line 62B supplies air from the outside to the exhaust gas cooled in the cooling tower 2 before being supplied to the blower 4. ２ This is a pipe that connects the outside of the recovery device 10B with the cooling line 3. In other words, the additional supply line 62B in the third embodiment is not connected to the exhaust line 9. The additional supply line 62B is connected to the cooling line 3 between the cooling tower 2 and the blower 4. Furthermore, a filter that can collect foreign matter such as dust in the air may be separately disposed in the additional supply line 62B.

[0050] (Effects) CO of the third embodiment ２In the recovery device 10B, when the opening degree of the flow rate control valve 63 is controlled by the supply amount adjustment unit 73, air is supplied from the atmosphere, rather than flue gas, via the additional supply line 62B. Therefore, air is sent to the flue gas flowing through the cooling line 3 via the flow rate adjustment valve 63. Therefore, not only the flue gas from which carbon dioxide has not been removed, which is sent from the cooling tower 2, but also air from the outside is supplied to the cooling line 3. As a result, a fluid containing a mixture of flue gas and air is supplied to the absorption tower 5, and the flow rate of the fluid supplied to the absorption tower 5 is increased. By increasing the flow rate of the fluid supplied to the absorption tower 5, the flow rate of the fluid flowing to the demister 52 within the absorption tower main body 51 increases. This maintains the flow rate of the fluid flowing to the demister 52 within the absorption tower main body 51 at a nearly constant value. In this way, even if the flow rate of the flue gas supplied from the flue gas generation source 20 decreases, it is possible to continue supplying a fluid at a constant flow rate to the demister 52 by using external air.

[0051] Furthermore, by supplying air instead of exhaust gas from the additional supply line 62B, there is no need to connect the additional supply line 62B from the exhaust line 9 to the cooling line 3. In other words, there is no need to route an exhaust gas duct from the outlet of the absorption tower 5, and the CO ２ The recovery device 10C can simplify the equipment.

[0052] Fourth Embodiment Next, a fourth embodiment of the present disclosure will be described. ２ The recovery device 10C will be described. In the fourth embodiment described below, components common to the first to third embodiments are denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. As shown in FIG. 4, the fourth embodiment differs from the second embodiment in that the additional supply line 62B is not connected to the exhaust line 9.

[0053] The flow rate adjusting unit 6C of the fourth embodiment supplies air as a fluid to the cooling line 3. The flow rate adjusting unit 6C of the fourth embodiment is the same as that of the third embodiment, except for the additional supply line 62B, which is different from that of the second embodiment.

[0054] (Operation and Effect) CO of the fourth embodiment ２In the recovery apparatus 10C, as in the third embodiment, when the opening degree of the flow rate adjustment valve 63 is controlled by the supply amount adjustment unit 73A, air is supplied from the atmosphere, rather than flue gas, via the additional supply line 62B. Therefore, air is sent to the flue gas that passes through the flow rate adjustment valve 63 and flows through the cooling line 3. In this way, the flow rate of the fluid flowing to the demister 52 in the absorption tower main body 51 is maintained at a nearly constant value by the fluid mixture of flue gas and air. In this way, even if the flow rate of the flue gas supplied from the flue gas generation source 20 decreases, it is possible to continue to supply fluid at a constant flow rate to the demister 52 by using external air.

[0055] Furthermore, even when air is supplied from additional supply line 62B, not only information on the pressure of the exhaust gas flowing through supply line 1 but also information on the flow rate of the exhaust gas flowing through cooling line 3 is used. Therefore, as in the second embodiment, a decrease in the amount of exhaust gas supplied to demister 52 can be detected quickly and with higher accuracy.

[0056] Furthermore, the flow rate at the blower 4 is adjusted based on information about the flow rate of the exhaust gas flowing through the cooling line 3. This allows for more precise adjustment of the flow rate of the exhaust gas supplied to the absorption tower 5. This therefore makes it possible to continue supplying exhaust gas at a constant flow rate to the demister 52 with high accuracy. Therefore, similar to the second embodiment, it is possible to suppress with higher accuracy a decrease in the flow rate of the exhaust gas supplied to the demister 52.

[0057] Fifth Embodiment Next, a CO ２ A recovery device 10D will be described. In the fifth embodiment described below, components common to the first to fourth embodiments are denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. As shown in Fig. 5, the fifth embodiment differs from the first to fourth embodiments in that the flow rate of the exhaust gas supplied to the demister 52 is controlled inside the absorption tower main body 51, rather than outside the absorption tower 5.

[0058] The flow rate adjustment unit 6D of the fifth embodiment is configured to keep the flow rate of the fluid flowing through the demister 52 within a predetermined range inside the absorber main body 51. The flow rate adjustment unit 6D of the fifth embodiment controls the flow rate of the flue gas supplied to the demister 52 inside the absorber main body 51. In other words, the flow rate adjustment unit 6D adjusts the flow rate of the fluid before being supplied to the demister 52 to a nearly constant state by keeping the flow rate of the flue gas supplied to the demister 52 inside the absorber main body 51 nearly constant. The flow rate adjustment unit 6D does not have a configuration outside the absorber main body 51 for controlling the flow rate of the flue gas supplied to the demister 52. The flow rate adjustment unit 6D has an internal adjustment unit 8D.

[0059] The internal adjustment unit 8D is disposed within the absorption tower main body 51. The internal adjustment unit 8D adjusts the flow rate of the fluid supplied to the demister 52 within the absorption tower main body 51 so that it falls within a predetermined reference range. As shown in FIG. 6 , the internal adjustment unit 8D is disposed upstream of the demister 52 in the exhaust gas flow direction. That is, the internal adjustment unit 8D is disposed below the demister 52 in the vertical direction Dv. In the fifth embodiment, when multiple demisters 52 (e.g., three layers) are disposed, the internal adjustment units 8D are disposed upstream of each demister 52 in a one-to-one relationship. Therefore, the same number of internal adjustment units 8D as the demisters 52 are disposed within the absorption tower main body 51. The internal adjustment units 8D are disposed in contact with the demisters 52. That is, the internal adjustment units 8D are disposed adjacent to and below the demisters 52 in the vertical direction Dv. Therefore, the multiple internal adjustment units 8D are disposed so as to block the inlets of the multiple demisters 52, respectively.

[0060] The internal adjustment unit 8D is a damper having a butterfly valve-like structure with multiple rotating blades 82. The internal adjustment unit 8D changes the flow rate of exhaust gas supplied to the demister 52 according to the rotation angle of the blades 82. In the internal adjustment unit 8D, the flow rate of exhaust gas supplied to the demister 52 is maximized by rotating the blades 82 until they are nearly parallel to the flow direction of the exhaust gas (extending straight with respect to the vertical direction Dv). In the internal adjustment unit 8D, the flow rate of exhaust gas supplied to the demister 52 is minimized by rotating the blades 82 until they are nearly perpendicular to the flow direction of the exhaust gas (extending perpendicular to the vertical direction Dv). In this way, the internal adjustment unit 8D of this embodiment adjusts the amount of exhaust gas supplied to the demister 52 so as to maintain a constant flow velocity of the exhaust gas supplied to the demister 52.

[0061] (Function and Effect) CO of the fifth embodiment ２ In the recovery apparatus 10D, the internal adjustment unit 8D adjusts the flow rate of the flue gas supplied to the demister 52 inside the absorption tower main body 51. In other words, even if the flow rate of the flue gas supplied to the absorption tower 5 decreases, the flow rate of the flue gas as it passes through the demister 52 inside the absorption tower main body 51 is directly adjusted. This allows the flow rate of the flue gas flowing through the demister 52 inside the absorption tower main body 51 to be maintained at a nearly constant value. In this way, even if the flow rate of the flue gas supplied from the flue gas generation source 20 decreases, the internal adjustment unit 8D can continue to supply flue gas at a constant flow rate to the demister 52. Therefore, a decrease in the flow rate of the flue gas supplied to the demister 52 can be suppressed.

[0062] Furthermore, the internal adjustment unit 8D is disposed at a position upstream of the demister 52 in the flow direction of the flue gas. Therefore, the internal adjustment unit 8D can adjust the flow velocity of the flue gas immediately before it passes through the demister 52 inside the absorption tower main body 51. This allows the flow velocity of the flue gas passing through the demister 52 inside the absorption tower main body 51 to be adjusted with higher precision.

[0063] Furthermore, the same number of internal adjustment units 8D as the number of demisters 52 are arranged inside the absorption tower main body 51. Therefore, regardless of the number of demisters 52 inside the absorption tower main body 51, the flow rate of the exhaust gas passing through the demisters 52 inside the absorption tower main body 51 can be adjusted with higher precision.

[0064] Furthermore, the internal adjustment unit 8D is disposed in contact with the demister 52. Therefore, regardless of the arrangement of the demister 52 within the absorption tower main body 51, the flow rate of the exhaust gas passing through the demister 52 within the absorption tower main body 51 can be adjusted with higher precision.

[0065] <First Modification> Next, a CO according to a first modification of the fifth embodiment of the present disclosure will be described. ２ The recovery device 10E will be described. In the first modification described below, the same components as those in the fifth embodiment are denoted by the same reference numerals in the drawings, and the description thereof will be omitted. As shown in FIG. 7, the CO ２ The recovery device 10E differs in the arrangement of the internal adjustment units 8E. The internal adjustment units are not limited to being arranged in a one-to-one relationship with the multiple demisters 52, as in the fifth embodiment. For example, only one internal adjustment unit 8E of the first modification may be arranged upstream of the multiple demisters 52 in the direction of exhaust gas flow. That is, only one internal adjustment unit 8E may be arranged below the most upstream (lowest) demister 52 in the vertical direction Dv. Even in this arrangement, it is preferable that the internal adjustment unit 8E be arranged in contact with the most upstream demister 52. That is, the internal adjustment unit 8E is arranged so as to block the inlet of the most upstream demister 52. The internal adjustment unit 8E also has a structure similar to that of the internal adjustment unit 8D of the fifth embodiment.

[0066] Such a first modified example of CO ２In the recovery apparatus 10E, the internal adjustment unit 8E is disposed at a position upstream of the multiple demisters 52 in the flow direction of the exhaust gas. Therefore, the internal adjustment unit 8E can adjust the flow rate of the exhaust gas immediately before it passes through the multiple demisters 52 within the absorption tower main body 51. As a result, the flow rate of the exhaust gas flowing through the multiple demisters 52 within the absorption tower main body 51 can be adjusted with a small number of internal adjustment units 8E.

[0067] <Second Modification> Next, a CO according to a second modification of the fifth embodiment of the present disclosure will be described. ２ The recovery device 10F will be described. In the second modification described below, the same components as those in the fifth embodiment will be denoted by the same reference numerals in the drawings, and the description thereof will be omitted. As shown in FIG. 8, the CO ２ The recovery device 10E differs in the location of the internal adjustment unit 8F. The internal adjustment unit 8F of the second modified example is not limited to being located upstream of the demister 52 in the exhaust gas flow direction, as in the fifth embodiment. For example, only one internal adjustment unit 8F may be located downstream of the demister 52 in the exhaust gas flow direction. More specifically, only one internal adjustment unit 8F may be located above the most upstream (lowest) demister 52 in the vertical direction Dv. Even in this location, it is preferable that the internal adjustment unit 8F be located in contact with the most upstream demister 52. In other words, the internal adjustment unit 8F is located so as to block the outlet of the most upstream demister 52. The internal adjustment unit 8F also has a structure similar to that of the internal adjustment unit 8D of the fifth embodiment.

[0068] Such a second modified example of CO ２ In recovery apparatus 10F, internal adjustment unit 8F is disposed downstream in the direction of exhaust gas flow in contact with demister 52 disposed at the most upstream (lowest layer). Even with the configuration of this second modified example, the flow rate of exhaust gas flowing through multiple demisters 52 within absorption tower body 51 can be adjusted in the same way as in the first modified example.

[0069] <Third Modification> Next, a CO according to a third modification of the fifth embodiment of the present disclosure will be described. ２A recovery device 10H will now be described. In the third modified example described below, components common to the fifth embodiment are denoted by the same reference numerals in the drawings and will not be described again. The internal adjustment unit 8F of the third modified example is not limited to being disposed solely downstream of the multiple demisters 52 in the exhaust gas flow direction, as in the second modified example. For example, the same number of internal adjustment units 8F may be disposed downstream of the multiple demisters 52 in a one-to-one relationship, as in the fifth embodiment. For example, the multiple internal adjustment units 8F may be disposed downstream of the multiple demisters 52 in a one-to-one relationship in the exhaust gas flow direction. Even in this arrangement, it is preferable that the multiple internal adjustment units 8F are disposed in contact with each of the multiple demisters 52. In other words, the multiple internal adjustment units 8F are disposed so as to block the outlets of the multiple demisters 52. The internal adjustment unit 8F also has a structure similar to that of the internal adjustment unit 8D of the fifth embodiment.

[0070] Such a third modified example of CO ２ Even in the recovery apparatus 10F, the internal adjustment units 8F are disposed adjacent to and downstream of the plurality of demisters 52 in the flow direction of the exhaust gas. Even with the configuration of this third modified example, the flow rate of the exhaust gas flowing through the plurality of demisters 52 inside the absorption tower body 51 can be adjusted in the same way as in the fifth embodiment.

[0071] (Other Embodiments) Although the embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope that does not deviate from the gist of the present disclosure are also included.

[0072] For example, each of the above-described embodiments may be combined with other embodiments. Specifically, the first embodiment may be combined with the second embodiment, or the third embodiment may be combined with the fourth embodiment. Furthermore, the fifth embodiment or its modified example may be combined with any of the first to fourth embodiments.

[0073] Furthermore, the additional supply lines 62, 62B are not limited to a structure that supplies only either the exhaust gas from which carbon dioxide has been removed or air. The additional supply lines 62, 62B may have a structure that can simultaneously supply the exhaust gas from which carbon dioxide has been removed and air, or a structure that can selectively supply the exhaust gas from which carbon dioxide has been removed and air. Furthermore, the additional supply lines 62, 62B may be capable of supplying a fluid (gas) other than the exhaust gas from which carbon dioxide has been removed and air.

[0074] Furthermore, the additional supply lines 62, 62B are not limited to being connected to the cooling line 3 between the cooling tower 2 and the blower 4, as long as they can supply a fluid to the exhaust gas before it is supplied to the absorber main body 5. For example, the additional supply lines 62, 62B may be connected to the cooling line 3 between the blower 4 and the absorber 5. Furthermore, the additional supply lines 62, 62B may be connected to the supply line 1.

[0075] <Additional Notes> CO described in each embodiment ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H can be understood, for example, as follows.

[0076] (1) CO according to the first aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H each include a cooling tower 2 into which exhaust gas containing carbon dioxide is introduced and which cools the exhaust gas, and an absorption tower 5 into which the exhaust gas cooled in the cooling tower 2 is introduced and which brings the exhaust gas into contact with an absorption liquid to remove the carbon dioxide from the exhaust gas, and the absorption tower 5 has a cylindrical absorption tower main body 51 through which the exhaust gas can flow, and a demister 52 disposed inside the absorption tower main body 51 and which can remove mist contained in the exhaust gas as the exhaust gas flows through it, and further includes flow rate adjustment units 6, 6A, 6B, 6C, and 6D which adjust the flow rate of the fluid flowing through the demister 52 within a predetermined range.

[0077] With this configuration, the flow rate of the exhaust gas flowing through the demister 52 is maintained at a nearly constant value. In this way, even if the flow rate of the exhaust gas supplied decreases, it is possible to continue supplying fluid at a constant flow rate to the demister 52. Therefore, it is possible to suppress a decrease in the flow rate of the fluid supplied to the demister 52.

[0078] (2) CO according to the second aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are CO ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the flow rate adjustment units 6, 6B include a differential pressure acquisition unit 61 that acquires information about the differential pressure between the pressure of the exhaust gas before it is supplied to the demister 52 in the absorption tower 5 and the pressure of the exhaust gas after it has passed through the demister 52 in the absorption tower 5, additional supply lines 62, 62B that supply a fluid to the exhaust gas before it is supplied to the absorption tower main body 5, a flow rate adjustment valve 63 that can adjust the supply amount of the fluid in the additional supply lines 62, 62B, and a control unit 7 that can control the aperture of the flow rate adjustment valve 63, and when the differential pressure acquired by the differential pressure acquisition unit 61 falls below a predetermined specified differential pressure value, the control unit 7 controls the flow rate adjustment valve 63 to increase the aperture.

[0079] According to this configuration, when the pressure difference within the absorber main body 51 falls below a specified pressure difference, the control unit 7 controls the opening degree of the flow control valve 63 to widen the opening degree. Therefore, the fluid that was sent to the additional supply lines 62, 62B is sent to the cooling line 3 through the flow control valve 63. That is, in addition to the flue gas sent from the cooling tower 2 before carbon dioxide removal, fluid is additionally supplied to the cooling line 3 from the additional supply lines 62, 62B. As a result, the flow rate of the fluid supplied to the absorber 5 is increased. By increasing the flow rate of the fluid supplied to the absorber 5, the flow rate of the fluid flowing to the demister 52 within the absorber main body 51 increases. This allows the flow rate of the fluid flowing to the demister 52 within the absorber main body 51 to be maintained at a nearly constant value. In this way, even if the flow rate of the supplied flue gas decreases, the decrease in the amount of fluid supplied to the demister 52 can be quickly detected by using information about the pressure difference around the demister 52 within the absorber main body 51, and fluid can be continuously supplied to the demister 52 at a constant flow rate. Therefore, a decrease in the flow rate of the fluid supplied to the demister 52 can be suppressed.

[0080] (3) CO according to the third aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are CO ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the flow rate adjustment units 6A and 6C include a pressure acquisition unit 65 that acquires information about the pressure of the exhaust gas before it is supplied to the cooling tower 2, additional supply lines 62 and 62B that supply a fluid to the exhaust gas before it is supplied to the absorption tower main body 5, a flow rate adjustment valve 63 that can adjust the flow rate of the fluid in the additional supply lines 62 and 62B, and a control unit 7A that can control the opening of the flow rate adjustment valve 63, and when the pressure acquired by the pressure acquisition unit 65 falls below a predetermined specified pressure value, the control unit 7A controls the opening of the flow rate adjustment valve 63 to be increased.

[0081] According to this configuration, when the pressure of the exhaust gas before being supplied to the cooling tower 2 falls below a specified pressure value, the control unit 7A controls the opening degree of the flow control valve 63 to widen the opening degree. Therefore, the exhaust gas sent to the additional supply lines 62, 62B is sent again to the cooling line 3 through the flow control valve 63. That is, not only the exhaust gas from which carbon dioxide has been removed sent from the cooling tower 2, but also fluid from the additional supply lines 62, 62B is additionally supplied to the cooling line 3. As a result, the flow rate of the fluid supplied to the absorber 5 is increased. By increasing the flow rate of the fluid supplied to the absorber 5, the flow rate of the fluid flowing to the demister 52 within the absorber main body 51 increases. This maintains the flow rate of the fluid flowing to the demister 52 within the absorber main body 51 at a nearly constant value. In this way, even if the flow rate of the supplied exhaust gas decreases, the decrease in the amount of fluid supplied to the demister 52 can be quickly detected by utilizing information about the pressure of the exhaust gas before being supplied to the cooling tower 2, and fluid can be continuously supplied to the demister 52 at a constant flow rate. Therefore, a decrease in the flow rate of the fluid supplied to the demister 52 can be suppressed.

[0082] (4) CO according to the fourth aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are CO ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H further include a flow rate increasing section that increases the flow rate of the exhaust gas cooled in the cooling tower 2 and supplies it to the absorption tower 5, and the flow rate adjusting sections 6A and 6C further include a flow rate acquiring section 66 that acquires information about the flow rate of the exhaust gas cooled in the cooling tower 2 and before being supplied to the flow rate increasing section, and the control section 7A controls the flow rate of the flow rate increasing section to be increased when the flow rate acquired by the flow rate acquiring section 66 falls below a predetermined specified flow rate value.

[0083] This configuration utilizes not only information about the pressure of the exhaust gas before it is supplied to the cooling tower 2, but also information about the flow rate of the exhaust gas before it is supplied to the flow velocity increasing section, making it possible to quickly and more accurately grasp a decrease in the amount of exhaust gas supplied to the demister 52.

[0084] (5) CO according to the fifth aspect２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are any one of (1) to (4) ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the additional supply line 62 supplies the flue gas from which the carbon dioxide has been removed in the absorption tower 5 as the fluid.

[0085] According to this configuration, by circulating the exhaust gas from which carbon dioxide has been removed through the additional supply line 62, it is possible to reuse the exhaust gas and increase the flow rate of the fluid supplied to the absorber 5 without separately preparing a new fluid. Furthermore, by supplying the exhaust gas from which carbon dioxide has been removed in the absorber 5 through the additional supply line 62, it is possible to reduce the amount of cold fluid supplied to the cooling line 3 compared to when atmospheric air is supplied to the cooling line 3. Furthermore, when supplying cold fluid, such as when the atmospheric temperature is low, it is necessary to prepare a separate heater to adjust the temperature before supplying the fluid to the cooling line 3. However, by re-supplying the exhaust gas through the additional supply line 62, it is possible to eliminate the need for temperature adjustment. Furthermore, the amount of oxygen contained in the exhaust gas is less than the amount of oxygen contained in the air. Therefore, it is possible to reduce the increase in the oxygen content in the fluid supplied to the absorber 5. As a result, it is possible to reduce the oxidative degradation of the absorption liquid that comes into contact with the exhaust gas, which is the fluid, in the absorber 5.

[0086] (6) CO according to the sixth aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are any one of (1) to (5) ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the additional supply line 62B supplies external air as the fluid.

[0087] According to this configuration, by supplying air from the additional supply line 62B, it is not necessary to connect the additional supply line 62B from the exhaust line 9 to the cooling line 3. In other words, it is not necessary to route an exhaust gas duct from the outlet of the absorption tower 5, and the CO ２The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H can simplify the equipment.

[0088] (7) CO according to the seventh aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are any one of (1) to (6) ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the flow rate adjustment units 6, 6A, 6B, 6C, and 6D are disposed inside the absorption tower main body 51 and have internal adjustment units 8D, 8E, 8F, and 8H that adjust the flow rate of the fluid supplied to the demister 52 to be within a predetermined reference range.

[0089] With this configuration, even if the flow rate of the exhaust gas supplied to the absorption tower 5 decreases, the flow rate of the fluid passing through the demister 52 inside the absorption tower main body 51 is directly adjusted. This allows the flow rate of the fluid flowing through the demister 52 inside the absorption tower main body 51 to be maintained at a nearly constant value. In this way, even if the flow rate of the exhaust gas supplied decreases, the internal adjustment units 8D, 8E, 8F, and 8H can continue to supply the fluid at a constant flow rate to the demister 52. Therefore, a decrease in the flow rate of the fluid supplied to the demister 52 can be suppressed.

[0090] (8) CO according to the eighth aspect ２ The recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H are CO ２ In the recovery devices 10, 10A, 10B, 10C, 10D, 10E, 10F, and 10H, the internal adjustment units 8D, 8E, 8F, and 8H are arranged in contact with the demister 52.

[0091] With this configuration, regardless of the arrangement of the demister 52 within the absorption tower body 51, the flow rate of the fluid passing through the demister 52 within the absorption tower body 51 can be adjusted with higher precision.

[0092] According to the CO2 recovery apparatus of the present disclosure, it is possible to suppress a decrease in the flow rate of the fluid supplied to the demister.

[0093] 10, 10A, 10B, 10C, 10D, 10E, 10F, 10H...CO ２ REFERENCE SIGNS LIST 1...Supply line 2...Cooling tower 3...Cooling line 4...Blower 5...Absorption tower 51...Absorption tower main body 52...Demister 6, 6A, 6B, 6C, 6D...Flow rate adjustment unit 61...Differential pressure acquisition unit 62, 62B...Additional supply line 63...Flow rate adjustment valve 7, 7A...Control unit 71, 71A...Input unit 72...Differential pressure determination unit 73, 73A...Supply amount adjustment unit 65...Pressure acquisition unit 66...Flow rate acquisition unit 74...Pressure determination unit 75...Flow rate determination unit 76...Blower adjustment unit 8D, 8E, 8F, 8H...Internal adjustment unit 82...Blade 9...Exhaust line 20...Exhaust gas generation source 30...Chimney Dv...Vertical direction

Claims

1. A CO absorbing system comprising: a cooling tower into which exhaust gas containing carbon dioxide is introduced and which cools the exhaust gas; and an absorption tower into which the exhaust gas cooled in the cooling tower is introduced and which brings the exhaust gas into contact with an absorbing liquid to remove the carbon dioxide from the exhaust gas, wherein the absorption tower has a cylindrical absorption tower body through which the exhaust gas can flow; and a demister disposed inside the absorption tower body and through which the exhaust gas flows, which is capable of removing mist contained in the exhaust gas, and further comprising a flow rate adjustment unit which adjusts the flow rate of the exhaust gas flowing through the demister within a predetermined range. ２ Recovery device.

2. The CO2 analyzer according to claim 1, wherein the flow rate adjustment unit has: a differential pressure acquisition unit that acquires information on a differential pressure between the pressure of the exhaust gas before it is supplied to the demister in the absorption tower and the pressure of the exhaust gas after it has passed through the demister in the absorption tower; an additional supply line that supplies a fluid to the exhaust gas before it is supplied to the absorption tower main body; a flow rate adjustment valve that is capable of adjusting the supply amount of the fluid in the additional supply line; and a control unit that is capable of controlling an aperture of the flow rate adjustment valve, and the control unit controls the aperture of the flow rate adjustment valve to be increased when the differential pressure acquired by the differential pressure acquisition unit falls below a predetermined specified differential pressure value. ２ Recovery device.

3. The CO2 absorber according to claim 1, wherein the flow rate adjustment unit has: a pressure acquisition unit that acquires information on the pressure of the exhaust gas before it is supplied to the cooling tower; an additional supply line that supplies a fluid to the exhaust gas before it is supplied to the absorption tower main body; a flow rate adjustment valve that can adjust the flow rate of the fluid in the additional supply line; and a control unit that can control an opening degree of the flow rate adjustment valve, and the control unit controls the opening degree of the flow rate adjustment valve to be increased when the pressure acquired by the pressure acquisition unit falls below a predetermined specified pressure value. ２ Recovery device.

4. The CO2 absorber according to claim 3, further comprising a flow rate increasing unit that increases the flow rate of the exhaust gas cooled in the cooling tower and supplies it to the absorption tower, wherein the flow rate adjusting unit further has a flow rate acquiring unit that acquires information on the flow rate of the exhaust gas cooled in the cooling tower and before being supplied to the flow rate increasing unit, and the control unit controls the flow rate of the flow rate increasing unit to be increased when the flow rate acquired by the flow rate acquiring unit falls below a predetermined specified flow rate value. ２ Recovery device.

5. The CO absorbing system according to claim 2, wherein the additional supply line supplies the flue gas from which the carbon dioxide has been removed in the absorption tower as the fluid. ２ Recovery device.

6. The CO purifier according to claim 2, wherein the additional supply line supplies outside air as the fluid. ２ Recovery device.

7. The CO2 absorber according to claim 1, wherein the flow rate adjusting unit has an internal adjusting unit that is disposed inside the absorption tower body and adjusts the flow rate of the exhaust gas supplied to the demister so that it falls within a predetermined reference range. ２ Recovery device.

8. The CO refrigeration system according to claim 7, wherein the internal adjustment section is disposed in contact with the demister. ２ Recovery device.

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