Carbon dioxide recovery device

Abstract

To provide a technology excellent in recovery capacity of carbon dioxide regardless of the properties of an absorbent.SOLUTION: A carbon dioxide recovery device which can alternately perform an absorption treatment for making an absorbent fluid absorb carbon dioxide contained in gas by bringing the gas in contact with the absorbent fluid in a treatment tank and a desorption treatment for desorbing carbon dioxide from the absorbent fluid subjected to the absorption treatment, comprises a restraint for restraining the production of a solid matter in the absorbent fluid.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The disclosed technology relates to a carbon dioxide recovery device.

Background Art

[0002] From the perspective of suppressing global warming, technologies for recovering carbon dioxide from gases such as air have attracted attention. Regarding absorbents for carbon dioxide, various studies are underway on absorbents that react with carbon dioxide at a low concentration such as in the atmosphere, absorbents aimed at improving the absorption rate of carbon dioxide and lowering the desorption temperature, etc.

[0003] Among the absorbents, some exhibit peculiar properties when absorbing carbon dioxide. For example, there are those in which solids precipitate from an aqueous solution, those that undergo phase separation (aqueous phase · oil phase), those that are not hydrophilic and dissolve in alcohol, etc., and they have a wide variety of properties.

[0004] Patent Document 1 discloses a carbon dioxide recovery technology in which, in an absorption and regeneration tower, a gaseous carbon dioxide is reactively absorbed by a lean carbon dioxide absorbent liquid to obtain a rich carbon dioxide absorbent liquid, and a regeneration step of recovering the carbon dioxide desorbed by heating the rich carbon dioxide absorbent liquid and obtaining a lean carbon dioxide absorbent liquid are alternately repeated.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the technology of Patent Document 1, when the rich carbon dioxide absorption liquid is stored in a stationary state where the operation of the device is stopped and regeneration and absorption are not performed, depending on the type of the absorption liquid, the reaction with carbon dioxide may proceed, and sedimentation and aggregation of solids generated from the rich carbon dioxide absorption liquid may occur inside the device. Sedimentation and precipitation of solids in the water pipe of the device may cause narrowing of the flow path due to a decrease in the inner diameter of the water pipe or blockage of the water pipe, etc., which may hinder smooth recovery of carbon dioxide.

[0007] That is, when carbon dioxide is recovered using the existing technology, since it is not possible to cope with the specific properties of the absorbent as described above, a decrease in the carbon dioxide recovery ability may occur.

[0008] In view of the above problems, the disclosed technology aims to provide a technology with excellent carbon dioxide recovery ability regardless of the properties of the absorbent. And one aspect of the present invention is to provide a technology that contributes to the improvement and development of a sustainable environment.

Means for Solving the Problems

[0009] A carbon dioxide recovery device according to one embodiment of the present invention is a carbon dioxide recovery device capable of alternately performing an absorption process of absorbing carbon dioxide contained in the gas into the absorption liquid by bringing the gas into contact with the absorption liquid inside the treatment tank, and a desorption process of desorbing the carbon dioxide from the absorption liquid that has been subjected to the absorption process, and is provided with a suppression means for suppressing the generation of solids in the absorption liquid stored in the treatment tank.

Effects of the Invention

[0010] According to the present invention, it is possible to provide a technology with excellent carbon dioxide recovery ability regardless of the properties of the absorbent.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of the features described in the embodiments are essential for the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Also, the same or similar configurations are given the same reference numerals, and duplicate explanations are omitted.

[0013] [Overview of Carbon Dioxide Recovery Device] FIG. 1 is a diagram showing a configuration example of a carbon dioxide recovery device 10 according to an embodiment. In the present embodiment, the process of absorbing carbon dioxide contained in the gas before treatment taken in from the outside into the absorption liquid is referred to as an absorption process, and the process of desorbing (releasing) carbon dioxide from the absorption liquid is referred to as a desorption process. Here, the absorption liquid is composed of an absorbent and a solvent. The absorbent is, for example, an amine-based compound and can absorb carbon dioxide. The solvent includes, for example, water, alcohols, ionic solutions, polar solvents, and the like.

[0014] The carbon dioxide recovery device 10 shown in FIG. 1 is a device capable of alternately performing an absorption process of bringing the gas before treatment (hereinafter also referred to as the gas before treatment) taken in from the outside into contact with the absorption liquid inside the treatment tank 101 to absorb carbon dioxide contained in the gas before treatment into the absorption liquid, and a desorption process of desorbing carbon dioxide from the absorption liquid in the treatment tank 101. The treatment tank 101 of the carbon dioxide recovery device 10 is also referred to as an absorption / desorption tank.

[0015] (Treatment tank 101) The treatment tank 101 of the carbon dioxide recovery device 10 is a container for performing the absorption process and the desorption process. A liquid storage unit 103 for storing the absorption liquid 200 is provided at the lower part of the treatment tank 101. The shape of the treatment tank 101 is not particularly limited as long as it forms a closed space so that the absorption liquid 200 stored in the liquid storage unit 103 and the mist diffused in the treatment tank 101 do not leak to the outside.

[0016] (Heating device HA1) The carbon dioxide recovery device 10 has a heating device HA1 that heats the absorption liquid 200. The heating device HA1 can heat the absorption liquid 200 to a predetermined temperature by using energy based on sunlight reception, heat transfer by a heat pump, and waste heat supplied from the outside. Note that the type of heat source is an example, and it is also possible to use other heat sources. The absorption liquid 200 sucked through the water pipe 301 by the pump P2 is pumped by the pump P2 and input into the heating device HA1 through the water pipe 302. The absorption liquid 200 heated by the heating device HA1 is returned to the treatment tank 101 through the water pipe 303. A first temperature sensor T-1 is provided on the water pipe 303, and the detected temperature of the first temperature sensor T-1 is input to the control device 30 (Fig. 3). The control device 30 (Fig. 8) controls the heating device HA1 to heat the absorption liquid 200 to a predetermined temperature based on the detected temperature of the first temperature sensor T-1.

[0017] Cooling devices (HE1, CR1) Furthermore, the carbon dioxide recovery device 10 has cooling devices (HE1, CR1) that cool the absorption liquid 200. The absorption liquid 200 sucked through the water pipe 401 by the pump P1 is pumped by the pump P1 and input into the cooling devices (HE1, CR1) through the water pipe 402. By the operation of the chiller CR1, the absorption liquid 200 cooled through the heat exchanger HE1 is returned to the treatment tank 101 through the water pipe 403. HE1 is a heat exchanger, and CR1 is a chiller. Heat exchange occurs between the heat exchanger HE1 and the chiller CR1, whereby the absorption liquid 200 is cooled, and the cooled absorption liquid 200 is returned to the treatment tank 101 through the water pipe 403. A second temperature sensor T-2 is provided on the water pipe 403, and the detected temperature of the second temperature sensor T-1 is input to the control device 30 (Fig. 8). The control device 30 controls the temperature of the cooling devices (HE1, CR1) to cool the absorption liquid 200 to a predetermined temperature based on the detected temperature of the second temperature sensor T-2.

[0018] (Gas-liquid contact device GL1) GL1 is a gas-liquid contact device, and the gas-liquid contact device GL1 discharges the absorbent liquid 200 returned through the water pipe 403 into the treatment tank 101. The gas-liquid contact device GL1 sprays the mist-like absorbent liquid 200, for example, by a spray nozzle, electrostatic atomization, rotary atomization, or ultrasonic atomization. In addition to spraying the absorbent liquid 200, a filler for increasing the contact area between the gas and the liquid may be installed in the treatment tank 101. The gas-liquid contact device GL1 may use these methods alone, or use a plurality of one method, or it is also possible to use a combination of different methods.

[0019] As an example, the gas-liquid contact device GL1 has a nozzle for spraying the absorbent liquid 200 in a mist form. Note that the number of nozzles for spraying the absorbent liquid is not limited to one, and a plurality of nozzles may be used. The gas-liquid contact device GL1 sprays the absorbent liquid 200 supplied from the water pipe 403 in a mist form. By spraying the absorbent liquid in a mist form, the contact between the gas before treatment in the treatment tank 101 and the absorbent liquid 200 can be increased.

[0020] The nozzle of the gas-liquid contact device GL1 has a structure for refining droplets during gas-liquid contact. As a structure for refining droplets, for example, the opening diameter may be processed to be less than a predetermined value, or a mesh may be formed at the opening of the nozzle so that the droplets of the sprayed absorbent liquid are finely dispersed. Alternatively, in order to suppress the growth of the droplets of the sprayed absorbent liquid by coalescence inside the treatment tank 101, the nozzle arrangement pitch may be set so that the nozzles are arranged at an interval or more apart from each other.

[0021] The gas-liquid contact device GL1 may be provided with a supply mechanism for supplying the same solvent as that contained in the absorbent liquid 200 to the gas-liquid contact device GL1 so that the absorbent liquid remaining in the gas-liquid contact device GL1 is discharged after the absorption treatment is completed.

[0022] (Fan F1) The fan F1 functions as a power source that creates a negative pressure inside the treatment tank 101 and takes in the gas before treatment into the treatment tank 101. The fan F1 is provided in the ventilation pipe 601. The ventilation pipe 601 (the first exhaust route) is a ventilation pipe that discharges low-concentration carbon dioxide. When the absorption treatment is carried out, the gas in the treatment tank is exhausted to the outside through the ventilation pipe 601 (the first exhaust route). The control device 30 (Figure 8) can control the operation of the fan F1, and by controlling the output of the fan F1, the amount of gas taken into the treatment tank 101 from the opening EN1 can be adjusted.

[0023] When the inside of the treatment tank 101 becomes negative pressure due to the operation of the fan F1, the gas before treatment is taken into the inside of the treatment tank 101 through the opening EN1. Due to the gas-liquid contact between the gas before treatment and the mist-like absorption liquid 200, the carbon dioxide contained in the gas before treatment reacts with the absorption liquid 200. As a result, the carbon dioxide is absorbed by the mist-like absorption liquid 200, and the absorption liquid 200 that has absorbed the carbon dioxide is returned to the liquid storage section 103. By continuously performing gas-liquid contact, the concentration of carbon dioxide in the absorption liquid stored in the liquid storage section 103 increases.

[0024] (Opening EN1) An opening EN1 is formed in the side wall of the treatment tank 101, and a door 102 is provided at the opening EN1. The door 102 can be opened and closed by the pressure difference between the inside and outside of the treatment tank 101. When the door 102 is open, the treatment tank 101 communicates with the outside world. When the door 102 is closed, the opening EN1 is sealed, and the inside of the treatment tank 101 is in a sealed state.

[0025] The door 102 is composed of, for example, a transparent member. When the door 102 is closed, the user can visually recognize the state inside the treatment tank 101 through the transparent member. The opening EN1 and the door 102 are not limited to one location, and a plurality of openings EN1 and doors 102 may be provided so that the inside of the treatment tank 101 can be visually recognized from different directions. When the door 102 is open, the user can also perform inspections, cleaning of the inside of the treatment tank 101, and replacement, adjustment, and maintenance work of suppression devices (dispersion device MX and separation device SE) described later.

[0026] Further, a filter (not shown) may be provided at the opening EN1. When the fan F1 operates, the inside of the treatment tank 101 becomes negative pressure, the door 102 opens, and the gas before treatment is taken into the treatment tank 101 through the filter. By passing the gas before treatment through the filter, dust contained in the gas before treatment can be removed. When the fan F1 stops and the flow of the gas before treatment stops, the door 102 closes. Note that the position where the fan F1 is provided is not limited to the ventilation pipe 601 and may be provided at a position near the opening EN1. Further, the fan F1 may be provided at both the ventilation pipe 601 and a position near the opening EN1.

[0027] (Concentration sensors CO-1, CO-2) The first concentration sensor CO-1 is a sensor that detects the concentration of carbon dioxide contained in the gas (gas before treatment), and the detection result detected by the first concentration sensor CO-1 is input to the control device 30 (FIG. 8).

[0028] The second concentration sensor CO-2 is a sensor that detects the carbon dioxide concentration of the gas after being absorbed by the absorbent 200 when the absorption treatment is performed, and detects the concentration of carbon dioxide desorbed from the absorbent 200 when the desorption treatment is performed. The detection result detected by the second concentration sensor CO-2 is input to the control device 30 (FIG. 8).

[0029] The detection result detected by the first concentration sensor CO-1 is the concentration of carbon dioxide (Den1) on the input side of the treatment tank 101, and the detection result detected by the second concentration sensor CO-2 is the concentration of carbon dioxide (Den2) on the output side of the treatment tank 101. The difference concentration (Den2 - Den1) between the two is an index (parameter) indicating the absorption amount of carbon dioxide absorbed by the absorbent 200 inside the treatment tank 101.

[0030] The control device 30 (Fig. 8) controls the switching between the absorption process and the desorption process based on the difference in the concentrations detected by the first concentration sensor CO-1 and the second concentration sensor CO-2. For example, when the difference in concentration becomes equal to or less than a predetermined differential concentration, the control device 30 switches from the absorption process to the desorption process. Further, when the concentration detected by the second concentration sensor becomes equal to or less than a predetermined concentration, the control device 30 switches from the desorption process to the absorption process. Note that the switching between the absorption process and the desorption process is not limited to the use of the information on the concentration of carbon dioxide, and the control device 30 may control the switching between the absorption process and the desorption process every time a predetermined period of time has elapsed.

[0031] (Devices MD1 and MD2 with automatic opening and closing mechanisms) The devices (MD1, MD2) with automatic opening and closing mechanisms are, for example, dampers and valves. Hereinafter, MD1 is also referred to as the first automatic opening and closing device, and MD2 is also referred to as the second automatic opening and closing device. By adjusting the opening degree of the devices (MD1, MD2) with automatic opening and closing mechanisms, the flow rate of the gas flowing through the ventilation pipe can be controlled. The first automatic opening and closing device MD1 controls the flow rate of the gas flowing through the ventilation pipe 501. Also, the second automatic opening and closing device MD2 controls the flow rate of the gas flowing through the ventilation pipe 601. The ventilation pipe 501 (the second exhaust route) is a ventilation pipe that discharges carbon dioxide at a higher concentration compared to the ventilation pipe 601. When the desorption process is executed, the gas in the treatment tank is exhausted to the outside through the ventilation pipe 501 (the second exhaust route). An air-cooling device AC1 (gas cooling device) is provided in the ventilation pipe 501, and the air-cooling device AC1 cools the gas flowing through the ventilation pipe 501 to a predetermined temperature. Also, a third temperature sensor T-3 is provided in the ventilation pipe 501, and the detected temperature of the third temperature sensor T-3 is input to the control device 30 (FIG. 8). The control device 30 detects the temperature of the gas flowing through the ventilation pipe 501 based on the detected temperature of the third temperature sensor T-3. Based on the detected temperature of the third temperature sensor T-3, the air-cooling device AC1 is controlled to cool the gas flowing through the ventilation pipe 501 to a predetermined temperature. In the present embodiment, the first automatic opening and closing device MD1 and the ventilation pipe 601 (the first exhaust route) function as an exhaust mechanism (the first exhaust mechanism) that exhausts the gas in the treatment tank 101 to the outside through the ventilation pipe 601 (the first exhaust route) when the absorption process is executed. Also, the second automatic opening and closing device MD2 and the ventilation pipe 501 (the second exhaust route) function as an exhaust mechanism (the second exhaust mechanism) that exhausts the gas in the treatment tank 101 to the outside through the ventilation pipe 501 (the second exhaust route) when the desorption process is executed.

[0032] [Suppression devices (MX, SE)] The carbon dioxide recovery device 10 of this embodiment includes a suppression device (MX, SE) that suppresses the generation of solids in the absorption liquid stored in the treatment tank 101. As one aspect of suppressing the generation of solids, the suppression device (MX, SE) may disperse the aggregation of solids in the absorption liquid 200. In the following description, the configuration of the suppression device (MX, SE) that disperses the aggregation of solids will be described as the dispersion device MX. Further, as another aspect of suppressing the generation of solids, the suppression device (MX, SE) may separate the solids from the absorption liquid. In the following description, the configuration of the suppression device (MX, SE) that separates the solids from the absorption liquid will be described as the separation device SE. The suppression device (MX, SE) may have either the dispersion device MX or the separation device SE, or may combine the device configurations of the dispersion device MX and the separation device SE. That is, the suppression device (MX, SE) includes at least one of a dispersion device MX that suppresses the aggregation of solids in the absorption liquid and a separation device SE that separates the solids from the absorption liquid.

[0033] [Dispersion device MX] The carbon dioxide recovery device 10 of this embodiment includes a dispersion device MX that suppresses the aggregation of solids in the absorption liquid stored in the liquid storage part 103 of the treatment tank 101. The dispersion device MX can apply various configurations as described below as a configuration for dispersing solids in the absorption liquid 200 stored in the liquid storage part 103 of the treatment tank 101. According to the dispersion device MX, by dispersing the solids without aggregating them, it is possible to suppress the growth into aggregates due to the union of solids, and thereby provide a carbon dioxide recovery device 10 having excellent carbon dioxide recovery ability regardless of the properties of the absorbent.

[0034] By using the configuration of the dispersion device MX in combination with the refinement of the droplets sprayed from the gas-liquid contact device GL1, it is possible to suppress the size of the solids (the core part of the solids) that can be generated in the initial stage, and prevent the enlargement of the solids in the initial stage. Thereby, the dispersion of the solids in the absorption liquid can be efficiently performed.

[0035] In addition, as the configuration of the dispersion device MX, the stirring device MX1, ultrasonic vibration device MX2, water flow generating device MX3, and surfactant input device MX4 described below may be used alone, or a plurality of devices may be used. Also, different types of devices may be combined and used. Further, although a configuration in which the processing of the dispersion device MX is performed inside the processing tank 101 is described, it may be performed by external equipment attached to the processing tank 101.

[0036] (Stirring device MX1) As an example of the dispersion device MX shown in FIG. 1, the stirring device MX1 stirs the absorption liquid 200 stored in the liquid storage section 103 by the rotation of the fan 114a. As a specific configuration, the stirring device MX1 includes a drive source 111 such as a motor, a connection flange 112, a shaft 113a connected to the drive source 111, and a fan 114a connected to the shaft 113a.

[0037] The connection flange 112 has a sealing function, and the drive source 111 is attached to the side surface of the processing tank 101 via the connection flange 112. The fan 114a is attached to the shaft 113, and the drive source 111 rotationally drives the fan 114a in the absorption liquid 200 via the shaft 113. When the fan 114a rotates in the absorption liquid 200, the absorption liquid 200 stored in the liquid storage section 103 is stirred. The stirring device MX1 is preferably installed on the side wall of the processing tank 101 downward so that the stirred water flow is directed downward so that solids settling below the liquid storage section 103 of the processing tank 101 or solids precipitated on the bottom of the processing tank 101 do not aggregate.

[0038] While the carbon dioxide recovery device 10 is performing the absorption process (during the P1 operation), the stirring device MX1 continues the operation of stirring the absorption liquid 200. Even at the start of the desorption process, the stirring device MX1 continues the operation of stirring the absorption liquid 200 so that the temperature of the absorption liquid 200 heated by the heating device HA1 becomes uniform in the processing tank 101.

[0039] When the temperature of the absorption liquid 200 rises to a predetermined temperature and the desorption of carbon dioxide proceeds, and the carbon dioxide absorbed by the absorption liquid decreases, the concentration of carbon dioxide in the treatment tank 101 becomes equal to or lower than a predetermined value, the desorption ends, and the stirring device MX1 stops operating.

[0040] When the temperature of the absorption liquid 200 drops below a predetermined value due to cooling by the cooling devices (HE1, CR1), the stirring device MX1 resumes the operation of stirring the absorption liquid 200.

[0041] (Ultrasonic vibration device MX2) FIG. 2 is a diagram showing a configuration example of the carbon dioxide recovery device 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals.

[0042] In the carbon dioxide recovery device 10 shown in FIG. 2, as an example of the dispersion device MX, it has an ultrasonic vibration device MX2. The ultrasonic vibration device MX2 generates ultrasonic vibrations based on a signal of a predetermined frequency in the absorption liquid stored in the liquid storage section 103 of the treatment tank 101. The ultrasonic vibration device MX2 has an oscillator 113b that generates a signal of a predetermined frequency and a vibrator 114b that vibrates based on the signal generated by the oscillator 113b. In the example shown in FIG. 2, the ultrasonic vibration device MX2 is installed in the treatment tank 101 via a connection flange 112. A plurality of ultrasonic vibration devices MX2 may be attached to the treatment tank 101 to ensure a wide ultrasonic generation area. The number of ultrasonic vibration devices MX2 to be attached may be changed according to the ultrasonic generation area. If a wide ultrasonic generation area can be ensured, even one ultrasonic vibration device MX2 may be sufficient. For example, by using an ultrasonic vibration device MX2 having a so-called throw-in type vibrator in which the vibrator 114b is formed in a cylindrical shape, a wide ultrasonic generation area can be ensured in the liquid storage section 103 of the treatment tank 101.

[0043] While the carbon dioxide recovery device 10 is performing the absorption process (during P1 operation), the ultrasonic vibration device MX2 continues to generate ultrasonic vibrations in the absorption liquid 200. When a plurality of ultrasonic vibration devices MX2 are provided in the treatment tank 101, it is also possible to control each ultrasonic vibration device MX2 to operate alternately. Even at the start of the desorption process, the ultrasonic vibration device MX2 continues to generate ultrasonic vibrations in the absorption liquid 200 so that the temperature of the absorption liquid 200 heated by the heating device HA1 becomes uniform within the treatment tank 101.

[0044] When the temperature of the absorption liquid 200 rises to a predetermined temperature and the desorption of carbon dioxide proceeds, and the amount of carbon dioxide absorbed by the absorption liquid decreases, the concentration of carbon dioxide in the treatment tank 101 becomes equal to or lower than a predetermined value, the desorption ends, and the ultrasonic vibration device MX2 stops operating.

[0045] When the temperature of the absorption liquid 200 drops below a predetermined value due to cooling by the cooling devices (HE1, CR1), the ultrasonic vibration device MX2 performs the operation of generating ultrasonic vibrations in the absorption liquid 200 again.

[0046] (Water flow generating device MX3) FIG. 3 is a diagram showing a configuration example of the carbon dioxide recovery device 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals.

[0047] In the carbon dioxide recovery device 10 shown in FIG. 3, as an example of the dispersion device MX, it has a water flow generating device MX3. The water flow generating device MX3 generates a water flow in the absorption liquid stored in the liquid storage part 103 of the treatment tank 101 based on the water supplied from the outside. The water flow generating device MX3 has, for example, a water flow generation source 113c including an underwater pump, a circulation pump, a circulator, etc. that receive the supply of water from the outside and output it. The water flow generating device MX3 can use any type of pump as long as it can generate a predetermined water flow in the absorption liquid 200 in the liquid storage part 103 by the output from the water flow generation source 113c.

[0048] The water flow generated by the water flow generating device MX3 flows toward the bottom surface of the treatment tank 101, and in order to generate a water flow in which the water flow hitting the bottom surface flows upward (arrows 113d, 113e), it is preferable to install the water flow generating devices MX1-3 obliquely downward with respect to the treatment tank 101.

[0049] While the carbon dioxide recovery device 10 is performing the absorption process (during the P1 operation), the water flow generating device MX3 continues to generate a predetermined water flow in the absorption liquid 200. When a plurality of ultrasonic vibration devices MX2 are operating, it is also possible to control them to operate alternately. At the start of the desorption process as well, the water flow generating device MX3 continues to generate a predetermined water flow in the absorption liquid 200 so that the temperature of the absorption liquid 200 heated by the heating device HA1 becomes uniform in the treatment tank 101.

[0050] When the temperature of the absorption liquid 200 rises to a predetermined value and the desorption of carbon dioxide progresses and the amount of carbon dioxide absorbed by the absorption liquid decreases, the concentration of carbon dioxide in the treatment tank 101 becomes equal to or lower than a predetermined value, the desorption ends, and the water flow generating device MX3 stops operating.

[0051] When the temperature of the absorption liquid 200 drops below a predetermined value due to cooling by the cooling devices (HE1, CR1), the water flow generating device MX3 performs the operation of generating a predetermined water flow in the absorption liquid 200 again.

[0052] (Surfactant dosing device MX4) FIG. 4 is a diagram showing a configuration example of the carbon dioxide recovery device 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals.

[0053] In the carbon dioxide recovery device 10 shown in FIG. 4, as an example of the dispersion device MX, it has a surfactant input device MX4 that inputs a surfactant into the absorption liquid 200. The surfactant input device MX4 (input device) inputs a surfactant that mixes well with the solvent used in the absorption liquid 200 into the absorption liquid 200 stored in the liquid storage part 103 of the treatment tank 101. The surfactant may be, for example, the same solvent as the absorption liquid 200, or even if it is a solid surfactant as long as a similar surfactant effect can be obtained, it is also possible to use it. When the absorption process and the desorption process are repeated a predetermined number of times, the surfactant input device MX4 inputs a predetermined amount of surfactant into the absorption liquid 200. When the carbon dioxide recovery device 10 executes the absorption process, the surfactant input device MX4 can make the concentration in the absorption liquid 200 uniform by inputting the surfactant.

[0054] (Absorption process (step) using the dispersion device MX) When executing the absorption process, the dispersion device MX (MX1, MX2, MX3, MX4) starts operating, and during the absorption process, the dispersion device MX continues to operate.

[0055] The device MD1 with an automatic opening and closing mechanism closes, and the device MD2 with an automatic opening and closing mechanism opens, thereby changing the air flow.

[0056] Next, the fan F1 operates. When the fan F1 operates, the inside of the treatment tank 101 becomes negative pressure, and the gas before treatment is taken into the inside of the treatment tank 101 from the opening EN1.

[0057] The pump P1 operates, and the absorption liquid 200 in the treatment tank 101 is pumped. The absorption liquid 200 sucked through the water pipe 401 by the pump P1 is pumped by the pump P1 and input into the cooling devices (HE1, CR1) through the water pipe 402. A second temperature sensor T-2 is provided on the water pipe 403, and the control device 30 (FIG. 8) controls the temperature of the cooling devices (HE1, CR1) so as to cool the absorption liquid 200 to a predetermined temperature based on the detected temperature of the second temperature sensor T-2.

[0058] By the operation of the chiller CR1, the absorbent liquid 200 cooled through the heat exchanger HE1 is returned to the treatment tank 101 through the water pipe 403. At this time, by the operation of the dispersion device MX, the absorbent liquid 200 stored in the liquid storage section 103 of the treatment tank 101 is in a state of being dispersed without phase separation.

[0059] The gas-liquid contact device GL1 discharges (sprays) the absorbent liquid 200 returned through the water pipe 403 into the treatment tank 101.

[0060] The gas to be treated taken into the inside of the treatment tank 101 through the opening EN1 and the absorbent liquid 200 sprayed by the gas-liquid contact device GL1 come into contact (gas-liquid contact), and carbon dioxide is recovered (absorbed) from the gas to be treated.

[0061] When the difference in the concentration of carbon dioxide detected by the first concentration sensor CO-1 and the second concentration sensor CO-2 becomes equal to or less than a certain value, the control device 30 (Fig. 8) determines that the absorption treatment has ended and shifts from the absorption treatment to the desorption treatment. Under the control of the control device 30, the fan F1, the chiller CR1, and the pump P1 stop operating.

[0062] (Desorption treatment (process) using the dispersion device MX) When performing the desorption treatment, the separation device MX (MX1, MX2, MX3, MX4) performs a switching operation according to the concentration of carbon dioxide in the treatment tank 101 detected by the second concentration sensor CO-2.

[0063] The device MD1 with an automatic opening and closing mechanism is opened, and the device MD2 with an automatic opening and closing mechanism is closed, thereby changing the air flow.

[0064] The door 102 can be opened and closed by the pressure difference between the inside and outside of the treatment tank 101. When the fan F1 stops and the flow of the gas to be treated stops, the door 102 is in a closed state.

[0065] Pump P2 operates, and the absorbent liquid 200 in the treatment tank 101 is pumped. The absorbent liquid 200 sucked through the water pipe 301 by the pump P2 is pumped by the pump P2 and input into the heating device HA1 through the water pipe 302.

[0066] The heating device HA1 operates, and the absorbent liquid 200 heated by the heating device HA1 is returned to the treatment tank 101 through the water pipe 303.

[0067] A first temperature sensor T-1 is provided on the water pipe 303, and the control device 30 (Fig. 8) controls the heating device HA1 to heat the absorbent liquid 200 to a predetermined temperature based on the detected temperature of the first temperature sensor T-1.

[0068] Since the absorbent liquid 200 stored in the liquid storage part 103 is stirred by the dispersion device MX, the temperature of the absorbent liquid 200 is made uniform. At this time, purge air is supplied to a purge supply part (not shown) provided inside the treatment tank 101 at a predetermined flow rate. The purge air is a gas that promotes the desorption of carbon dioxide from the absorbent liquid 200. The configuration of the purge supply part may be the same as that of the gas-liquid contact device GL1.

[0069] When the second concentration sensor CO-2 detects that the concentration of carbon dioxide in the treatment tank 101 has risen above a predetermined value, the air cooling device AC starts operating, and the air containing high-concentration carbon dioxide flowing through the ventilation pipe 501 is air-cooled.

[0070] When the concentration of carbon dioxide detected by the second concentration sensor CO-2 drops below a predetermined value, the control device 30 (Fig. 8) determines that the desorption process has ended and shifts from the desorption process to the absorption process. Under the control of the control device 30, the pump P2, the heating device HA1, and the air cooling device AC stop operating.

[0071] [Separation device SE] The carbon dioxide recovery device 10 of this embodiment includes a separation device SE that separates the solid matter generated in the absorption liquid 200 from the absorption liquid 200 by absorbing carbon dioxide, as a configuration for suppressing the generation of solid matter in the absorption liquid 200. The dispersion device SE can apply various configurations as described below as a configuration for separating solid matter from the absorption liquid 200 stored in the liquid storage section 103 of the treatment tank 101. According to the separation device SE, by separating the generated solid matter from the absorption liquid 200, it is possible to provide a carbon dioxide recovery device 10 that is excellent in carbon dioxide recovery ability regardless of the properties of the absorbent.

[0072] Note that as the separation ability of solid matter in the separation device SE, it does not need to separate all of the solid matter in the absorption liquid 200. As long as the separation ability is such that solid matter of a size with a low risk of blockage due to flowing into the water pipe passes through the separation device SE. Thereby, the energy consumption in the separation device SE can be suppressed, and the maintenance load can be reduced. Since the solid matter that can be an obstacle to the stable carbon dioxide recovery process is separated (removed) from the absorption liquid 200 by the separation device SE of this embodiment, stable liquid transportation is possible in the carbon dioxide recovery device 10.

[0073] When the solid matter is precipitated by the reaction of amine and carbon dioxide, in order to desorb carbon dioxide, it is necessary to bring the solid matter and the absorption liquid into contact again at the desorption stage. In such a case, the heated absorption liquid 200 during the execution of the desorption process may be supplied to the separation device SE and brought into contact with the solid matter again.

[0074] In the separation device SE, if it is a configuration that does not operate by power such as a drive source (for example, the solid-liquid separation membrane SE2 or the porous separation layer SE3 described later), by using the inclination to allow the absorption liquid 200 to flow, the solid matter remaining on the solid-liquid separation membrane SE2 or the porous separation layer SE3 and the absorption liquid 200 can be efficiently brought into contact. Thereby, it becomes possible to stably perform the carbon dioxide desorption process.

[0075] If it is a configuration that operates by power such as a drive source (for example, a modification example of the centrifugal separator SE1 or the porous separation layer SE3 described later), by rotating the rotating body 507 of the centrifugal separator SE1 at a low speed or the like, the solid matter remaining in the centrifugal separator SE1 and the absorption liquid 200 can be efficiently brought into contact with each other. Further, for example, if it is a modification example of the porous separation layer SE3 described later, by moving the porous separation layer SE3 up and down in the vertical direction by the elevating device 701 and immersing the porous separation layer SE3 in the absorption liquid 200 in the liquid storage section 103, the solid matter remaining in the porous separation layer SE3 and the absorption liquid 200 can be efficiently brought into contact with each other. As a result, it becomes possible to stably perform the carbon dioxide desorption treatment.

[0076] Note that as the configuration of the separation device SE, the centrifugal separator SE1, the solid-liquid separation membrane SE2, and the porous separation layer SE3 described below may be used alone, or a plurality of devices may be used. Further, different types of devices may be combined and used. In addition, although the configuration in which the treatment of the separation device SE is performed inside the treatment tank 101 is described, it may be performed by external equipment attached to the treatment tank 101.

[0077] (Centrifugal Separator SE1) FIG. 5A is a diagram showing a configuration example of the carbon dioxide recovery device 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals. In FIG. 5A, the water pipe 303B is a water pipe for supplying the absorption liquid 200 heated by the heating device HA1 to the separation device SE (SE1).

[0078] In the carbon dioxide recovery device 10 shown in Fig. 5A, as an example of the separation device SE, it has a centrifugal separation device SE1. Fig. 5B is a diagram schematically showing the operation of the centrifugal separation device SE1. The centrifugal separation device SE1 has a rotating body 507, a spindle 502 attached to the rotating body 507, and a drive unit 503 that rotates the rotating body 507 via the spindle 502. A container (not shown) for storing the absorption liquid 200 to be centrifuged is stored in the rotating body 507. A separation plate 505 is provided in the container. The separation plate 505 is formed with openings having, for example, a predetermined gap. An opening / closing part 506 is provided at the bottom of the rotating body 507. When the opening / closing part 506 closes, the container of the rotating body 507 and the liquid storage part 103 are in a non-communicating state, and when the opening / closing part 506 opens, the container of the rotating body 507 and the liquid storage part 103 are in a communicating state. In addition, in Fig. 5A and Fig. 5B, an example in which the separation plate 505 is provided in the container is shown as a configuration example of the centrifugal separation device SE1, but it is not limited to this example. As shown in Fig. 5C, if the solid matter 504 can be collected on the side of the container of the rotating body 507 by the action of the centrifugal force, the separation plate 505 may not be provided.

[0079] ST51 in Fig. 5B shows a state in which a predetermined amount of the absorption liquid 200 has accumulated in the container of the rotating body 507. The absorption liquid 200 contains the solid matter 504, and the solid matter 504 is in a dispersed state in the absorption liquid 200. The opening / closing part 506 is in a closed state.

[0080] ST52 in Fig. 5B shows a state in which the rotating body 507 is rotating. The opening / closing part 506 is in a closed state. Due to the rotation of the rotating body 507, the centrifugal force acts on the solid matter 504. By centrifugal treatment, the solid matter 504 passes through the opening of the separation plate 505 by the action of the centrifugal force and is collected on the side of the container of the rotating body 507.

[0081] In ST53, the rotation of the rotating body 507 stops and the opening / closing part 506 is open. When the opening / closing part 506 opens, the container of the rotating body 507 and the liquid storage part 103 are in a communicating state, and the absorption liquid 200 from which the solid matter 504 has been separated is returned to the liquid storage part 103.

[0082] While the carbon dioxide recovery device 10 is performing the absorption process (during P1 operation), the absorption liquid 200 sprayed from the gas-liquid contact device GL1 is supplied to the container of the rotating body 1 of the centrifugal separator SE1 (ST51). With a predetermined amount of the absorption liquid 200 accumulated in the container, the centrifugal separator SE1 operates and the rotating body 507 rotates (ST52). After the rotation operation of the centrifugal separator, the opening / closing part 506 opens, and the absorption liquid 200 from which the solid matter 504 has been separated is returned to the liquid storage part 103 (ST53). While the absorption process is being performed, the processes from ST51 to ST53 are repeatedly executed.

[0083] When the carbon dioxide recovery device 10 performs the desorption process, the centrifugal separator SE1 is in a stopped state. The absorption liquid 200 heated by the heating device HA1 is supplied to the centrifugal separator SE1 via the water pipe 303. The absorption liquid 200 (solid-liquid mixed solution) containing the solid matter 504 is supplied to the rotating body 507 of the centrifugal separator SE1. As a result of the absorption liquid 200 (solid-liquid mixed solution) being heated by the heating device HA1, desorption progresses. Due to desorption, the solid matter 504 is reduced or removed from the absorption liquid 200 (solid-liquid mixed solution). The absorption liquid 200 from which the solid matter 504 has been reduced (removed) is returned to the liquid storage part 103 after a predetermined time has elapsed, and the desorption process is repeated, and the absorption liquid 200 is heated in that process.

[0084] Basically, the centrifugal separator SE1 is stopped, but when supplying the heated absorption liquid 200 (solid-liquid mixed solution) to the centrifugal separator SE1, in order to promote desorption, the rotating body 507 may be rotated at a low speed so as to increase the contact between the solid matter 504 remaining in the container of the rotating body 507 and the absorption liquid 200 (solid-liquid mixed solution).

[0085] (Solid-liquid separation membrane SE2) FIG. 6A is a diagram showing a configuration example of the carbon dioxide recovery device 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals. In FIG. 6A, the water pipe 303B is a water pipe that supplies the absorption liquid 200 heated by the heating device HA1 to the separation device SE (SE2).

[0086] In the carbon dioxide recovery device 10 shown in Fig. 6A, as an example of the separation device SE, it has a solid-liquid separation membrane SE2. The solid-liquid separation membrane SE2 reduces the solids contained in the absorption liquid and filters the absorption liquid. The solid-liquid separation membrane SE2 is installed inclined with respect to the liquid level of the absorption liquid 200 stored in the liquid storage section 103 in the treatment tank. As shown in Fig. 6A, the solid-liquid separation membrane SE2 is installed with an inclination at a predetermined angle (θ) with respect to the liquid level of the liquid storage section 103.

[0087] While the carbon dioxide recovery device 10 is performing the absorption process (during P1 operation), the absorption liquid 200 sprayed from the gas-liquid contact device GL1 is supplied to the solid-liquid separation membrane SE2. The absorption liquid 200 is filtered by the solid-liquid separation membrane SE2, solids remain on the solid-liquid separation membrane SE2, and the absorption liquid 200 passes through the solid-liquid separation membrane SE2 and is stored in the liquid storage section 103.

[0088] When the carbon dioxide recovery device 10 performs the desorption process, the absorption liquid 200 heated by the heating device HA1 is supplied to the upper part of the solid-liquid separation membrane SE2 and comes into contact with the solids remaining on the solid-liquid separation membrane SE2. Although the absorption liquid 200 itself passes through the solid-liquid separation membrane SE2 and falls into the liquid storage section 103, the heated absorption liquid 200 is intermittently supplied to the solids on the solid-liquid separation membrane SE2. As a result, the solids are heated and desorption progresses.

[0089] FIG. 6B is a diagram showing a modified example of the configuration example of the carbon dioxide recovery device of FIG. 6A. In FIG. 6B, the solid-liquid separation membrane SE2 is configured in an endless belt shape. The belt-shaped solid-liquid separation membrane SE2 is mounted on pulleys 61 and 62. One of the pulleys 61 and 62 is a driving pulley connected to a driving source (not shown), and the other is a driven pulley. As the driving source, it is possible to use an underwater motor or the like so that it can be used even in an environment where the mist-like absorption liquid 200 is sprayed or in an environment immersed in the liquid storage unit 103. The control device 30 (FIG. 8) controls the driving source to move the belt-shaped solid-liquid separation membrane SE2 in the direction indicated by the arrow when performing the absorption process and the desorption process, respectively. The belt-shaped solid-liquid separation membrane SE2 is installed such that the upper side (SE2_1) in the side view of the solid-liquid separation membrane SE2 is located above the liquid level of the absorption liquid 200 stored in the liquid storage unit 103 of the treatment tank 101, and the lower side (SE2_2) in the side view of the solid-liquid separation membrane SE2 contacts the absorption liquid 200. The solid-liquid separation membrane SE2 is mounted on a driving pulley rotated by a driving source and a driven pulley, and the upper side (SE2_1) in the side view of the solid-liquid separation membrane SE2 and the lower side (SE2_2) in the side view of the solid-liquid separation membrane SE2 are switched according to the execution of the absorption process or the desorption process.

[0090] During the execution of the absorption process (during the P1 operation), the absorption liquid 200 is filtered by the solid-liquid separation membrane SE2, solids remain on the solid-liquid separation membrane SE2 on the upper side (SE2_1) in the side view, and the absorption liquid 200 passes through the solid-liquid separation membrane SE2 and is stored in the liquid storage unit 103.

[0091] When performing the desorption process, the belt-shaped solid-liquid separation membrane SE2 moves in the arrow direction, and the solid-liquid separation membrane SE2 located on the upper side (SE2_1) in the side view moves to the lower side (SE2_2) in the side view. During the execution of the desorption process, since the absorption liquid 200 heated by the heating device HA1 circulates, the liquid temperature of the absorption liquid 200 in the liquid storage unit 103 rises. The solids remaining during the absorption process come into contact with the absorption liquid 200 whose liquid temperature has risen due to heating, so that the solids are heated and as a result, the desorption proceeds. Thereby, the desorption process can be efficiently executed.

[0092] (Porous Separation Layer SE3) FIG. 7A is a diagram showing a configuration example of the carbon dioxide recovery apparatus 10 according to the embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals. In FIG. 7A, the water pipe 303B is a water pipe that supplies the absorbent liquid 200 heated by the heating device HA1 to the separation device SE (SE3).

[0093] In the carbon dioxide recovery apparatus 10 shown in FIG. 7A, as an example of the separation device SE, it has a porous separation layer SE3. The porous separation layer SE3 only needs to have a structure that does not allow solids to pass through but only allows liquids to pass through, and the porous separation layer SE3 may be a porous body as an example. As the shape of the porous separation layer SE3, in a side view of the treatment tank 101, the central portion CP is formed to be inclined downward toward the lower part of the treatment tank 101. For example, the central portion CP may have a shape that curves downward or a concave shape. As the thickness of the cross-sectional shape, it is preferably formed with a predetermined thickness along the radial direction of the treatment tank 101.

[0094] In FIG. 7A, as an example of the porous separation layer SE3, an example of a shape in which the central portion CP is inclined downward is shown. While the carbon dioxide recovery apparatus 10 is performing the absorption process (during operation P1), the absorbent liquid 200 sprayed from the gas-liquid contact device GL1 is supplied to the porous separation layer SE3. The supplied absorbent liquid 200 is concentrated on the central portion CP due to the inclination formed in the porous separation layer SE3. The absorbent liquid 200 is filtered by the porous separation layer SE3, solids remain in the central portion CP of the porous separation layer SE3, and the absorbent liquid 200 passes through the porous separation layer SE3 and is stored in the liquid storage portion 103.

[0095] When the carbon dioxide recovery apparatus 10 performs the desorption process, the absorbent liquid 200 heated by the heating device HA1 is supplied to the upper part of the porous separation layer SE3 and contacts the solids remaining on the porous separation layer SE3. Although the absorbent liquid 200 itself passes through the porous separation layer SE3 and falls into the liquid storage portion 103, the heated absorbent liquid 200 is intermittently supplied to the solids on the porous separation layer SE3. As a result, the solids are heated and desorption proceeds accordingly.

[0096] FIG. 7B is a diagram showing a modified example of the configuration example of the carbon dioxide recovery device of FIG. 7A. The porous separation layer SE3 is vertically held by a lifting device 701 provided inside the treatment tank 101 so as to be movable up and down. The lifting device 701 can move the held porous separation layer SE3 vertically upward or vertically downward by the driving force of a driving source (not shown). FIG. 7C is a diagram schematically showing the operation of the porous separation layer SE3 that moves up and down in the vertical direction by the lifting device 701. In FIG. 7C, ST71 shows a state where the porous separation layer SE3 has risen, and ST72 shows a state where the porous separation layer SE3 has descended. When performing the absorption treatment, the porous separation layer SE3 is held such that the central portion CP of the porous separation layer SE3 is positioned above the liquid level of the absorption liquid 200 stored in the treatment tank 101. When performing the desorption treatment, the central portion CP of the porous separation layer SE3 is held in contact with the absorption liquid 200.

[0097] When solid-liquid separation is performed in the state of ST71, not only solid matter 704 accumulates on the surface of the porous separation layer SE3, but solid matter 704 may enter the internal cavities of the porous separation layer SE3. In such a case, the control device 30 (FIG. 8) controls the driving source of the lifting device 701 to lower the porous separation layer SE3 (ST72) so that the porous separation layer SE3 is immersed in the absorption liquid 200 in the liquid storage unit 103. The control device 30 (FIG. 8) raises the porous separation layer SE3 when performing the absorption treatment and lowers the porous separation layer SE3 when performing the desorption treatment. Thereby, the absorption treatment and the desorption treatment can be efficiently performed.

[0098] (Absorption treatment (process) using the separation device SE) When performing the absorption treatment, the separation device SE (SE1, SE2, SE3) starts operating, and the separation device SE continues to operate during the absorption treatment.

[0099] The device MD1 with an automatic opening and closing mechanism closes, and the device MD2 with an automatic opening and closing mechanism opens, thereby changing the air flow.

[0100] Next, the fan F1 operates. When the fan F1 operates, the inside of the treatment tank 101 becomes negative pressure, and the gas before treatment is taken into the inside of the treatment tank 101 from the opening EN1.

[0101] The pump P1 operates to pump the absorption liquid 200 in the treatment tank 101. The absorption liquid 200 sucked through the water pipe 401 by the pump P1 is pumped by the pump P1 and input into the cooling device (HE1, CR1) through the water pipe 402. A second temperature sensor T-2 is provided on the water pipe 403, and the control device 30 (FIG. 8) controls the temperature of the cooling device (HE1, CR1) so as to cool the absorption liquid 200 to a predetermined temperature based on the detected temperature of the second temperature sensor T-2.

[0102] Due to the operation of the chiller CR1, the absorption liquid 200 cooled through the heat exchanger HE1 is returned to the treatment tank 101 through the water pipe 403.

[0103] The gas-liquid contact device GL1 discharges (sprays) the absorption liquid 200 returned through the water pipe 403 into the treatment tank 101. The gas before treatment taken into the inside of the treatment tank 101 through the opening EN1 and the absorption liquid 200 sprayed by the gas-liquid contact device GL1 come into contact (gas-liquid contact), and carbon dioxide is recovered (absorbed) from the gas before treatment.

[0104] The absorption liquid 200 that has undergone gas-liquid contact is supplied to the separation device SE. The solid matter separated by the separation device SE remains in the separation device SE, and the absorption liquid 200 that has passed through the separation device SE falls into the liquid storage unit 103 and is stored.

[0105] When the difference in the concentration of carbon dioxide detected by the first concentration sensor CO-1 and the second concentration sensor CO-2 becomes equal to or less than a certain value, the control device 30 (FIG. 8) determines that the absorption treatment has ended and shifts from the absorption treatment to the desorption treatment. Under the control of the control device 30, the fan F1, the chiller CR1, and the pump P1 stop operating.

[0106] (Desorption treatment (process) using the separation device SE) When the device MD1 with an automatic opening and closing mechanism is opened and the device MD2 with an automatic opening and closing mechanism is closed, the air flow is changed.

[0107] The door 102 can be opened and closed by the pressure difference between the inside and outside of the treatment tank 101. When the fan F1 stops and the flow of the gas before treatment stops, the door 102 is in a closed state.

[0108] The pump P2 operates, and the absorption liquid 200 in the treatment tank 101 is pumped. The absorption liquid 200 sucked through the water pipe 301 by the pump P2 is pumped by the pump P2 and input into the heating device HA1 through the water pipe 302.

[0109] When the heating device HA1 operates, the absorption liquid 200 heated by the heating device HA1 is returned to the treatment tank 101 through the water pipe 303.

[0110] A first temperature sensor T-1 is provided on the water pipe 303, and the control device 30 (Fig. 8) controls the heating device HA1 to heat the absorption liquid 200 to a predetermined temperature based on the detected temperature of the first temperature sensor T-1.

[0111] The absorption liquid 200 heated by the heating device HA1 is supplied to the separation device SE and contacts the solid matter remaining in the separation device SE. The solid matter remaining during the absorption treatment contacts the absorption liquid 200 whose liquid temperature has risen due to heating, so that the solid matter is heated and as a result, the desorption progresses.

[0112] At this time, purge air is supplied to a purge supply section (not shown) provided inside the treatment tank 101 at a predetermined flow rate. The purge air is a gas that promotes the desorption of carbon dioxide from the absorption liquid 200. The configuration of the purge supply section may be the same as that of the gas-liquid contact device GL1.

[0113] When it is detected by the second concentration sensor CO-2 that the concentration of carbon dioxide in the treatment tank 101 has risen above a predetermined value, the air cooling device AC starts operating, and the air containing high-concentration carbon dioxide flowing through the ventilation pipe 501 is air-cooled.

[0114] When the concentration of carbon dioxide detected by the second concentration sensor CO-2 drops below a predetermined value, the control device 30 (Fig. 8) determines that the desorption process has ended and shifts from the desorption process to the absorption process. Under the control of the control device 30, the pump P2, the heating device HA1, and the air cooling device AC stop operating.

[0115] [Control device] Fig. 8 is a control block diagram of the carbon dioxide recovery device 10 according to the embodiment. The control device 30 includes a processing unit 31 (processor), an interface unit 32, and a storage unit 33. The processing unit 31 is a general-purpose integrated circuit for executing the operations of the carbon dioxide recovery device 10. The processing unit 31 may be configured by, for example, a central processing unit (CPU). The processing unit 31 executes various processes by reading and executing the programs stored in the storage unit 33. The storage unit 33 stores control information corresponding to various operation modes, and the processing unit 31 executes processes corresponding to the absorption process or the desorption process based on the control information.

[0116] The interface unit 32 is an interface for various sensor groups 38 and device groups 39 included in the carbon dioxide recovery device 10, and the processing unit 31 (processor) controls the device group 39 based on the information acquired from the sensor group 38 via the interface unit 32.

[0117] Here, the sensor group 38 includes, for example, a first concentration sensor CO-1, a second concentration sensor CO-2, a first temperature sensor T-1, a second temperature sensor T-2, and a third temperature sensor T-3.

[0118] Further, the device group 39 includes devices MDi (i = 1, 2), MD2) with automatic opening and closing mechanisms, an air cooling device AC1, a fan F1, cooling devices (HE1, CR1), pumps Pi (i = 1, 2), a heating device HA1, a gas-liquid contact device GL1, a dispersion device MX, and a separation device SE. The carbon dioxide recovery device 10 includes at least one of the dispersion device MX and the separation device SE.

[0119] The storage unit 33 is a device for storing information used in the operation of the carbon dioxide recovery device 10, software, and reference values (threshold values) for comparison with information detected by various sensors. The storage unit 33 may be configured by a hard disk drive (HDD) or a solid state drive (SSD).

[0120] The input device 25 is a device that receives input from a user who operates the carbon dioxide recovery device 10, and may be, for example, a keyboard, a mouse, or a touch panel type device. The display device 26 is a device that presents the operating state of the carbon dioxide recovery device 10 to the user. The processing unit 31 functions as a display control unit, and presents various sensor information in the sensor group 38, such as the amount of carbon dioxide acquired and the concentration of the acquired carbon dioxide, to the display device 26, for example.

[0121] As described above, according to the technologies disclosed by the embodiments and the modification examples, it is possible to provide a technology excellent in carbon dioxide recovery ability regardless of the properties of the absorbent.

[0122] [Other Embodiments] In addition, a program that realizes one or more functions described in each embodiment is supplied to a control device via a network or a storage medium, and one or more processors in a computer of the system or the control device can read and execute this program. The present invention can also be realized in such a manner.

[0123] The present invention is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

Explanation of Reference Numerals

[0124] 10: Carbon dioxide recovery device, 30: Control device, 101: Processing tank, 103: Liquid storage unit, MX: Separation device, SE: Separation device

Claims

1. A carbon dioxide recovery device capable of alternately performing an absorption process of absorbing carbon dioxide contained in the gas into the absorption liquid by bringing the gas into contact with the absorption liquid inside the treatment tank and a desorption process of desorbing the carbon dioxide from the absorption liquid that has undergone the absorption process, comprising suppression means for suppressing the generation of solids in the absorption liquid stored in the treatment tank. A carbon dioxide recovery device characterized by this.

2. The absorption liquid contains an absorbent and a solvent, The absorbent contains an amine-based compound capable of absorbing carbon dioxide, The solvent contains at least one of water, alcohols, ionic liquids, and polar solvents. The carbon dioxide recovery device according to claim 1, characterized by this.

3. The suppression means is stirring means for stirring the absorption liquid stored in the treatment tank, means for generating ultrasonic vibration in the stored absorption liquid, water flow generation means for generating a water flow in the stored absorption liquid, input means for inputting a surfactant into the stored absorption liquid, centrifugal separation means for centrifugally separating the solids from the absorption liquid, a solid-liquid separation membrane installed inclined with respect to the liquid level of the absorption liquid stored in the treatment tank, a porous separation layer formed such that the central portion inclines downward in the treatment tank in a side view of the treatment tank, and includes at least any one of them. The carbon dioxide recovery device according to claim 1, characterized by this.

4. The solid-liquid separation membrane is formed in an endless belt shape. The upper side of the solid-liquid separation membrane in side view is located above the liquid level of the absorption liquid stored in the treatment tank, and the lower side of the solid-liquid separation membrane in side view is installed so as to be in contact with the absorption liquid. The carbon dioxide recovery device according to claim 3, characterized in that.

5. The solid-liquid separation membrane is mounted on a driving pulley rotated by a driving source and a driven pulley. The upper side of the solid-liquid separation membrane in side view and the lower side of the solid-liquid separation membrane in side view are switched in accordance with the execution of the absorption treatment or the desorption treatment. The carbon dioxide recovery device according to claim 4, characterized in that.

6. The porous separation layer is formed with a predetermined thickness in the radial direction of the treatment tank. The carbon dioxide recovery device according to claim 3, characterized in that.

7. The porous separation layer is held by a lifting means provided inside the treatment tank so as to be liftable in the vertical direction. The holding position of the porous separation layer is switched in accordance with the execution of the absorption treatment or the desorption treatment. The carbon dioxide recovery device according to claim 3, characterized in that.

8. When the absorption treatment is executed, the central portion of the porous separation layer is held so as to be located above the liquid level of the absorption liquid stored in the treatment tank, and when the desorption treatment is executed, the central portion of the porous separation layer is held so as to be in contact with the absorption liquid. The carbon dioxide recovery device according to claim 7, characterized in that.

9. When the absorption treatment is executed, a cooling means for cooling the absorption liquid pumped from the treatment tank by the operation of a first pump to a predetermined temperature, Cooling liquid supply means for returning the absorption liquid cooled by the cooling means to the treatment tank. The carbon dioxide recovery device according to claim 1, further comprising. Characterized in that.

10. The cooling means includes a chiller and a heat exchanger. The carbon dioxide recovery device according to claim 9, wherein the absorbent liquid is cooled through the heat exchanger by the operation of the chiller.

11. The carbon dioxide recovery device according to claim 1, wherein a door that opens and closes according to the pressure inside the treatment tank is provided at the opening of the treatment tank.

12. The carbon dioxide recovery device according to claim 11, further comprising a fan provided on a first exhaust route for exhausting the gas in the treatment tank to the outside when the absorption treatment is performed.

13. The carbon dioxide recovery device according to claim 12, further comprising gas cooling means provided on a second exhaust route for exhausting the gas in the treatment tank to the outside when the desorption treatment is performed, and cooling the gas flowing through the second exhaust route to a predetermined temperature.

14. When the desorption treatment is performed, heating means for heating the absorbent liquid pumped from the treatment tank to a predetermined temperature by the operation of a second pump; Heating liquid supply means for supplying the absorbent liquid heated by the heating means to the suppression means; and The carbon dioxide recovery device according to claim 1, wherein the solid matter separated from the absorbent liquid by the suppression means and remaining in the suppression means comes into contact with the heated absorbent liquid.

15. A first concentration sensor for detecting the concentration of carbon dioxide contained in the gas taken in from the opening of the treatment tank; A second concentration sensor for detecting the carbon dioxide concentration of the gas after being absorbed by the absorbent liquid when the absorption treatment is performed, and detecting the concentration of carbon dioxide desorbed from the absorbent liquid when the desorption treatment is performed; The carbon dioxide recovery device according to claim 1, further comprising control means for controlling the switching between the absorption treatment and the desorption treatment.

16. The control means When the difference in the concentrations detected by the first concentration sensor and the second concentration sensor becomes equal to or less than a predetermined differential concentration, the switching is made from the absorption process to the desorption process. The carbon dioxide recovery device according to claim 15, wherein when the concentration detected by the second concentration sensor becomes equal to or less than a predetermined concentration, the switching is made from the desorption process to the absorption process.

17. The carbon dioxide recovery device according to claim 15, wherein the control means controls the switching at every elapse of a predetermined time.

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