JP2020022947A - Adsorption completion determination method of carbon dioxide adsorption apparatus and carbon dioxide adsorption apparatus - Google Patents

Abstract

To provide an adsorption completion determination method of a carbon dioxide adsorption apparatus and the carbon dioxide adsorption apparatus where the completion of adsorption is stably determined regardless of the fluctuation of a gas to be treated.SOLUTION: In a carbon dioxide adsorption method by a carbon dioxide adsorption apparatus where a gas to be treated containing carbon dioxide is introduced into a reaction vessel from the gas inlet of the reaction vessel 106 having the gas inlet 136a and a gas outlet 136b and being filled with a carbon dioxide adsorbent 105 inside and the adsorption of carbon dioxide by the carbon dioxide adsorbent is performed in the reaction vessel,: the gas to be treated and the adsorbent are contacted in the reaction vessel and carbon dioxide in the gas to be treated is adsorbed by the adsorbent; a gas outflowing from the gas outlet of the reaction vessel is flown into an adsorption completion determination device 101; the temperature of the inlet 131a of the gas to be treated at the adsorption completion determination device filled with a reactant 104 with carbon dioxide inside and the temperature of the outlet 131b of the gas to be treated are measured; and the completion of adsorption is determined according to the temperature of the inlet of the gas to be treated and the temperature of the outlet of the gas to be treated or the reactant by the adsorption completion determination device.SELECTED DRAWING: Figure 1

Description

  The present invention uses a solid adsorbent and determines the end of adsorption in the adsorption process of a carbon dioxide adsorption device that adsorbs carbon dioxide of a gas to be treated containing carbon dioxide. The present invention relates to a method and a carbon dioxide adsorption device.

  The main cause of global warming is anthropogenic carbon dioxide, and the need for significant reductions in carbon dioxide emissions has been raised internationally. In order to achieve this significant reduction in carbon dioxide emissions, energy conversion measures, conversion to energy with lower carbon content, and conversion and development to renewable energy are carried out, while fossil fuels such as coal, heavy oil, or natural gas are used. Development and verification tests of technology for separating and recovering carbon dioxide in combustion exhaust gas discharged during use and accumulating it in the ground have been promoted internationally.

  As a method for separating carbon dioxide in the combustion exhaust gas, a solid material in which an amine compound or potassium carbonate is supported on a porous body such as activated carbon or silica is filled in a reaction vessel, and a treatment containing carbon dioxide is performed in the vessel. By contact with a gas, carbon dioxide is selectively adsorbed (Patent Document 1). The adsorbent after adsorbing the carbon dioxide stops the flow of the gas to be treated into the reaction vessel, and then desorbs the adsorbed carbon dioxide by heating or reducing the pressure of the reaction vessel. As a result, the adsorbent is regenerated while recovering its adsorption ability. The regenerated adsorbent can be repeatedly used for adsorbing carbon dioxide by bringing it into contact with the gas to be treated containing carbon dioxide again.

  When such adsorption of carbon dioxide and regeneration of an adsorbent are performed continuously, a “fixed bed system” is adopted in which a plurality of reaction vessels are provided to perform adsorption and desorption alternately (Patent Document 2). .

  Further, as a method of a switching cycle between adsorption and desorption in these cases, a method of detecting the concentration of carbon dioxide in the reaction vessel with a sensor and switching at a predetermined time interval have been proposed (Patent Documents). 3).

  FIG. 5 is a schematic configuration diagram of a carbon dioxide adsorption device 10 described in Patent Document 3. The reaction vessels 12 and 18 are filled with the adsorbent 14, respectively, and the direction of the gas to be treated introduced by the two-way valve 22 is controlled. In FIG. 5, the gas to be treated is introduced into the reaction vessel 12 by the two-way valve 22, and the reaction vessel 12 is in a state of adsorbing carbon dioxide. The gas to be treated having carbon dioxide adsorbed is discharged from the reaction vessel 12 to the outside of the reaction vessel 12 by the discharge valve 24. The adsorption of carbon dioxide by the reaction container 12 is performed until the determination of the end of adsorption by the carbon dioxide concentration sensor 30 provided in the reaction container 12 or the switching of the two-way valve 22 at predetermined time intervals. When the adsorption of carbon dioxide in the reaction vessel 12 is completed, the gas to be treated is introduced into the reaction vessel 18 by the two-way valve 22, and the reaction vessel 18 is brought into a state of adsorbing carbon dioxide. At this time, the adsorbed carbon dioxide is desorbed in the reaction vessel 12, and the desorbed carbon dioxide is discharged to the recovery side by the recovery valve 28. The reaction vessel 12 from which carbon dioxide has been desorbed can be used again for carbon dioxide adsorption. As described above, the configuration of the carbon dioxide adsorption apparatus in FIG. 5 is configured to alternately adsorb and desorb carbon dioxide in each of the two reaction vessels.

Japanese Patent Publication No. 3-7413 Patent No. 5571085 JP 2000-502289 A

  However, the method for determining the end of adsorption by the carbon dioxide concentration sensor proposed in Patent Document 3 is expensive, the response is slow, and errors due to contamination in the gas in the reaction vessel or condensation of moisture are large. It was difficult to determine stably in use. In addition, since the switching at a preset time interval cannot cope with fluctuations in the flow rate of the gas to be treated or the concentration of carbon dioxide containing carbon dioxide, the adsorption capacity is set to prevent the leakage of carbon dioxide that could not be adsorbed from the reaction vessel. The time was set so that there was a lot of room.

  The present invention solves the above-mentioned conventional problems, and provides an adsorption termination determination method and a carbon dioxide adsorption device of a carbon dioxide adsorption device that stably determines the termination of adsorption regardless of a change in a gas to be treated. With the goal.

According to one aspect of the present invention, there is a gas inlet and a gas outlet, and a gas to be treated containing carbon dioxide is introduced into the reaction vessel from the gas inlet of the reaction vessel filled with a carbon dioxide adsorbent. Introducing, in the method of adsorbing carbon dioxide by a carbon dioxide adsorbing device performing carbon dioxide adsorption with a carbon dioxide adsorbent in the reaction vessel,
A first step of contacting the gas to be treated and the adsorbent in the reaction vessel to adsorb carbon dioxide of the gas to be treated to the adsorbent;
A second step of causing the gas flowing out of the gas outlet of the reaction vessel to flow into an adsorption termination determiner;
A third step of measuring the temperature of the gas-to-be-treated and the temperature of the gas-to-be-treated of the adsorption completion determiner filled with a reactant with carbon dioxide,
A fourth step of determining the end of the adsorption process according to the temperature of the gas-to-be-treated and the temperature of the gas-to-be-processed of the adsorption-completion determiner, provide.

  As described above, according to the aspect of the present invention, regardless of the fluctuation of the gas to be treated, the temperature of the gas to be treated and the temperature downstream of the gas to be treated, for example, The end of adsorption can be determined stably according to the temperature of the gas outlet or the temperature of the reactant.

Schematic configuration diagram of a representative carbon dioxide adsorption device in an embodiment of the present invention Graph showing the change in carbon dioxide concentration on the outlet side of the reaction vessel when the gas to be treated containing carbon dioxide is subjected to adsorption treatment in the reaction vessel. Graph showing the change in the inlet / outlet gas temperature difference ΔT when the gas to be treated containing carbon dioxide flows in the adsorption termination determiner Schematic configuration diagram of another carbon dioxide adsorption device according to an embodiment of the present invention Schematic configuration diagram of a carbon dioxide adsorption device in a conventional embodiment Schematic configuration diagram of a carbon dioxide adsorption device according to Embodiment 2 of the present invention In the adsorption termination determiner according to Embodiment 2 of the present invention, the temperature difference ΔT ₁ between the inlet gas and the reactant when the gas to be treated containing carbon dioxide flows, and the carbon dioxide concentration change on the exit side of the adsorption termination determiner Graph showing Schematic configuration diagram of a carbon dioxide adsorption device in Embodiment 3 of the present invention In the adsorption termination determiner according to Embodiment 3 of the present invention, the temperature difference ΔT _a, ΔT _b, ΔT between the inlet gas and the reactant upstream, middle, and downstream when the gas to be treated containing carbon dioxide flows. Graph showing _c and the change in carbon dioxide concentration at the exit side of the adsorption termination determiner

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a typical carbon dioxide adsorption device 150 according to an embodiment of the present invention. In FIG. 1, the carbon dioxide adsorption device 150 includes an adsorption end determination unit 101, temperature sensors 102 and 103, and a control unit 120.

  The reaction vessel 106 has a gas inlet 136a and a gas outlet 136b, and the inside is filled with the carbon dioxide adsorbent 105.

  The adsorption end determining device 101 has a gas inlet 131a to be processed and a gas outlet 131b to be processed. The to-be-processed gas inlet 131a is directly connected to the gas outlet 136b of the reaction vessel 106 by the pipe 121. The adsorption termination determiner 101 is filled with a reactant 104 with carbon dioxide. The reactant 104 has a general property that the temperature rises due to an adsorption reaction with carbon dioxide.

  The temperature sensors 102 and 103 are disposed at the gas-to-be-treated inlet 131a and the gas-to-be-processed outlet 131b of the adsorption completion determination unit 101, respectively, and measure the temperature of the gas to be treated.

The control unit 120 receives information on the temperatures T ₁₀₂ and T ₁₀₃ detected by the temperature sensors 102 and 103 on the inlet side and the outlet side, respectively. The control unit 120, a calculation unit 120a for determining the temperature difference ΔT of the temperature _{T 102, T 103 (= T} 103 -T 102), based on the temperature difference ΔT obtained by the calculation unit 120a, the opening and closing operation control such as a valve And an operation control unit 120b. Therefore, the control unit 120 determines the end of the suction based on the temperature difference ΔT between the temperatures T ₁₀₂ and T ₁₀₃ detected by the temperature sensors 102 and 103, respectively. The control unit 120 can control the opening and closing of the gas opening and closing valve 107 based on the determination result.

  In addition, in order to remove an error or the like due to disturbance, a threshold value may be provided, the temperature difference ΔT may be compared with the threshold value, and only when the temperature difference ΔT exceeds the threshold value, it may be determined that the adsorption is completed. .

  The gas opening / closing valve 107 is disposed in the pipe 122 connected to the gas inlet 136a of the reaction vessel 106. The gas opening / closing valve 107 controls the supply of the gas to be treated containing carbon dioxide sent from the carbon dioxide-containing gas introduction unit 109 by the blower pump 108 to the reaction vessel 106 by opening and closing. The arrow 111 indicates the direction of the gas flow.

  Hereinafter, a method of adsorbing carbon dioxide by the carbon dioxide adsorption device 150 of the present embodiment will be described with reference to FIG.

  The gas to be treated containing carbon dioxide is introduced into the reaction vessel 106 from the gas inlet 136a via the gas opening / closing valve 107 by the blower pump 108 from the carbon dioxide-containing gas introduction unit 109.

  Next, the carbon dioxide present in the gas to be treated comes into contact with the carbon dioxide adsorbent 105 filled in the reaction vessel 106, and only carbon dioxide is selectively adsorbed on the carbon dioxide adsorbent 105.

  Next, the gas to be treated to which carbon dioxide is adsorbed passes from the gas outlet 136b of the reaction vessel 106, passes through the inside of the adsorption termination determiner 101 via the gas to be treated 131a, is discharged from the gas to be treated 131b, and is discharged as off-gas. It flows into the pipe 123 of the discharge channel. The adsorption of carbon dioxide in the reaction vessel 106 is performed until the end of the adsorption is determined by the adsorption end determiner 101. This determination operation will be described later. When the adsorption is completed, the gas opening / closing valve 107 is closed under the control of the control unit 120, whereby the introduction of the gas to be treated containing carbon dioxide into the reaction vessel 106 is stopped.

  As a subsequent step, the carbon dioxide adsorbent 105 desorbs the carbon dioxide adsorbed by the carbon dioxide adsorbent 105 filled in the reaction vessel 106 by heating or depressurizing the reaction vessel 106. The carbon dioxide adsorbent 105 from which carbon dioxide has been desorbed is regenerated by recovering its adsorption ability, and can be repeatedly used for carbon dioxide adsorption by bringing it into contact with the gas to be treated containing carbon dioxide again. The desorbed carbon dioxide is discharged to the pipe 123 of the discharge channel. As described above, the configuration of the carbon dioxide adsorption device 150 in FIG. 1 is configured to alternately adsorb and desorb carbon dioxide.

  Next, the action of carbon dioxide adsorption in the reaction vessel 106 will be described with reference to FIG. The amount of carbon dioxide that can be adsorbed per unit time of the carbon dioxide adsorbent 105 filled in the reaction vessel 106 is determined. Therefore, in order to completely adsorb carbon dioxide in the flow of the gas to be treated, it is necessary to contact the gas to be treated with the carbon dioxide adsorbent 105 for a certain distance (that is, time). When adsorbing carbon dioxide in the reaction vessel 106, the carbon dioxide adsorbent 105 is used sequentially from the upstream side of the gas stream to be treated. Therefore, in the initial stage of the adsorption, the contact distance between the gas to be treated and the carbon dioxide adsorbent 105 can be ensured, so that the carbon dioxide in the gas to be treated is completely adsorbed. When the carbon dioxide adsorbent 105 on the downstream side of the gas to be treated is used, the contact distance between the gas to be treated and the carbon dioxide adsorbent 105 cannot be sufficiently ensured, and the carbon dioxide in the gas to be treated that cannot be adsorbed flows from the reaction vessel 106. Will leak.

  FIG. 2 is a graph showing a change in carbon dioxide concentration on the gas outlet 136b side of the reaction vessel 106 when a gas to be treated containing carbon dioxide (carbon dioxide concentration 10%, 20%) is subjected to an adsorption treatment in the reaction vessel 106. It is. It can be seen from FIG. 2 that as the end of adsorption approaches, carbon dioxide is rapidly leaking from the gas outlet 136b side of the reaction vessel 106. The amount of carbon dioxide leaking from the reaction vessel 106 until the end of the adsorption varies depending on the shape of the reaction vessel 106, the type of the carbon dioxide adsorbent, the condition of the processing gas, and the like. It is possible to know the amount of carbon dioxide leakage X in the system.

  Next, the operation of the adsorption completion determiner 101 that determines the end of adsorption in the reaction vessel 106 will be described with reference to FIG.

The adsorption termination determiner 101 is filled with a reactant 104 having a temperature change due to a reaction with carbon dioxide. Further, temperature sensors 102 and 103 on the inlet side and the outlet side are disposed at the gas inlet 131a and the gas outlet 131b of the adsorption end determiner 101, respectively. Temperature _{T 102} of the processing gas inlet 131a of the suction end judgment unit 101 respectively detected by the temperature sensor 102 and 103 and the temperature _{T 103} of the processing gas outlet 131b is input to the control unit 120. The control unit 120 constantly monitors the temperature difference ΔT (= T ₁₀₃ −T ₁₀₂ ) of the gas at the entrance and exit. In the adsorption step, in a range in which the carbon dioxide adsorbent 105 filled in the reaction vessel 106 completely adsorbs carbon dioxide in the gas to be treated, the adsorption completion determiner 101 does not include carbon dioxide. Since the gas to be processed flows from the reaction vessel 106, no temperature difference ΔT occurs between the temperature sensors 102 and 103. However, when the end of the adsorption is approaching and the carbon dioxide leaks from the reaction vessel 106 to the adsorption end determiner 101, the reaction between the reactant 104 filled in the adsorption end determiner 101 and the carbon dioxide determines the end of the adsorption. Since the gas to be processed flowing into the vessel 101 is heated, a temperature difference ΔT occurs between the temperature sensors 102 and 103 between the inlet side and the outlet side.

  FIG. 3 shows the entrance / exit of the adsorption completion determiner 101 when a gas to be treated containing carbon dioxide (for example, a gas with a carbon dioxide concentration of 10% and a gas of 20%) flows into the adsorption completion determiner 101. 5 is a graph showing a change in a gas temperature difference ΔT. From FIG. 3, it can be seen that the reaction between the reactant 104 and the carbon dioxide causes a temperature difference ΔT between the inlet and outlet gases of the adsorption termination determiner 101.

  The method of determining the end of adsorption according to the present embodiment is a method of determining the occurrence of the temperature difference ΔT between the inlet and outlet gases. The heating of the gas to be treated by the reactant 104 that causes the temperature difference ΔT in the inlet / outlet gas depends on the amount of carbon dioxide leaking from the reaction vessel 106 to the adsorption completion determiner 101. The temperature difference ΔT does not depend on the flow rate of the gas to be treated introduced into the reaction vessel 106 or the concentration of carbon dioxide contained in the gas to be treated. Therefore, the adsorption end determination method of the present embodiment can stably determine the end of adsorption without being affected by the fluctuation of the gas to be treated. As a result, in the adsorption step of the carbon dioxide adsorption apparatus, it is not necessary to always terminate the adsorption step with a sufficient amount of adsorbent, thereby reducing the frequency of replacement of the adsorbent and contributing to cost reduction. .

  It should be noted that carbon dioxide is introduced into the adsorption termination determiner 101, and the amount of carbon dioxide Y1 and the temperature difference ΔT of the inlet / outlet gas which flow until the temperature difference ΔT occurs in the inlet / outlet gas (see point A in FIG. 3) are reduced to a peak. The amount of carbon dioxide Y2 introduced before turning over (see point B in FIG. 3) varies depending on the shape of the adsorption completion determiner 101, the type of the reactant 104, the condition of the processing gas, and the like. It is possible to know the amount of carbon dioxide introduced in each system.

  In the present embodiment, the end of the adsorption is determined when the carbon dioxide leaks from the reaction vessel 106 to the adsorption end judging device 101 and the temperature difference ΔT between the inlet and the outlet of the adsorption end judging device 101 occurs. However, the amount of carbon dioxide leaking X leaking from the reaction vessel 106 and the amount of carbon dioxide Y1 required to cause a temperature difference ΔT between the inlet and outlet gases of the adsorption termination determiner 101 (see point A in FIG. 3) are set to the same value. When the setting is made, it is possible to make the adsorption end determination time of the adsorption end determiner 101 and the end time of the adsorption capability of the carbon dioxide adsorbent the same.

  Further, the amount of carbon dioxide Y2 introduced before the temperature difference ΔT of the inlet / outlet gas turns to peak down (see point B in FIG. 3) is set to be larger than the amount of carbon dioxide leakage X from the previous reaction vessel 106. When the adsorption termination determiner 101 is used, that is, when it is determined that the peak of the inlet / outlet gas temperature difference ΔT is reduced in the system of the adsorption process that satisfies the condition of the following equation (1), the carbon dioxide filled in the reaction vessel 106 is determined. The carbon adsorbent 105 is completely used.

Y2> X Expression (1)
As the material used as the reactant 104 according to the present embodiment, at least one kind of amine substance is used, and various amine compounds are suitable. Many belong to the following categories: Selected from the group consisting of aliphatic primary, secondary and tertiary amines, and polyamines, polyimines (eg, polyalkylene imines), cyclic amines, amidine compounds, hindered amines, amino-siloxane compounds, amino acids, and combinations thereof. It is desirable that this is an amine compound.

  Examples of the material used as the carbon dioxide adsorbent 105 according to the present embodiment include activated carbon, silica, alumina, and the like, a porous body such as an acrylate resin, or a substance in which an amine compound is supported on the porous body. Can be

  As the temperature sensors 102 and 103 according to the present embodiment, a thermistor, a resistance temperature detector, a thermocouple, an IC temperature sensor, or the like is used.

  As the control unit 120 according to the present embodiment, a PC (that is, a personal computer), a PLC (that is, a programmable logic controller), a smart relay, or the like is used.

  In the present embodiment, the number of the reaction vessels 106 and the adsorption completion determiners 101 is the same as one. However, the number may be two or more, or may not be the same.

  FIG. 4 is a schematic configuration diagram of a carbon dioxide adsorption device 150A according to another embodiment. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

  In FIG. 4, two first and second reaction vessels 106a and 106b are arranged, and two first and second adsorption completion determiners 101a and 101b are arranged. The flow direction changing valve 112 allows the gas to be treated containing carbon dioxide sent from the carbon dioxide-containing gas introduction unit 109 by the blower pump 108 to be introduced or changed into any one of the reaction vessels 106a and 106b. Has become. In the embodiment of FIG. 4, when carbon dioxide is adsorbed in one of the reaction vessels 106a or 106b, the adsorbed carbon dioxide is desorbed in the other reaction vessel 106b or 106a. The adsorption and desorption of carbon dioxide are alternately performed in the respective reaction vessels 106a and 106b. This makes it possible to continuously process the gas to be treated containing carbon dioxide, and to increase the total amount of the carbon dioxide adsorbent 105, thereby reducing the frequency of replacement and providing an option for coping with failure. There are effects such as increase.

  The temperature sensors 102a and 102b on the inlet side and the temperature sensors 103a and 103b on the outlet side are respectively connected to the control unit 120 so that the end of adsorption can be determined based on the temperature difference ΔT in each gas processing line.

  In the present embodiment and another embodiment, the reaction vessels 106, 106a, 106b and the adsorption completion determiners 101, 101a, 101b are installed vertically, respectively. As long as the flow flows from the suction end determination units 101, 101a, and 101b from the suction end determination units 101, 101a, and 101b, the flow may be horizontal, vertical, or horizontal.

  According to the above embodiment, the end of adsorption is stabilized in accordance with the temperature of the gas inlet 131a and the temperature of the gas outlet 131b of the adsorption end determiners 101, 101a, 101b regardless of the fluctuation of the gas to be processed. Can be determined.

(Embodiment 2)
FIG. 6 is a schematic configuration diagram of a carbon dioxide adsorption device 150B according to the second embodiment. 6, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 6, instead of the temperature sensor 103 on the outlet side, the temperature sensor 110 is arranged inside the adsorption end determination unit 101 instead of the gas outlet 131 b of the adsorption end determination unit 101. The temperature sensor 110 on the inside thereof can accurately measure a temperature change by directly measuring the temperature of the reactant 104 by contacting the reactant 104. As temperature sensor 110, the same as temperature sensor 102 or 103 of Embodiment 1 can be used. A temperature _{T 110} of the reactants 104 detected by the temperature _{T 102} and the temperature sensor 110 of the processing gas inlet 131a of the suction end judgment unit 101 detected by the temperature sensor 102 is input to the control unit 120.

The control unit 120 constantly monitors the temperature difference ΔT ₁ (= T ₁₁₀ −T ₁₀₂ ) between the gas inlet 131 a of the adsorption end determination unit 101 and the reactant 104. End of the adsorption approached, the carbon dioxide is leaking to the suction end determination unit 101 from the reaction vessel 106, the temperature difference [Delta] T ₁ between the reactant 104 and the inlet gas of the adsorption end determination unit 101 increases.

FIG. 7 shows the change in the temperature difference ΔT ₁ between the gas inlet 131 a and the reactant 104 when a gas to be treated containing carbon dioxide (carbon dioxide concentration: 20%) is flown into the adsorption completion determination unit 101. It is a graph shown. The temperature difference ΔT ₁ started to increase after 10 minutes from the start of the evaluation (see point A in FIG. 7), peaked around 20 minutes, and then gradually decreased.

FIG. 7 also shows a change in the concentration of carbon dioxide on the outlet side of the adsorption termination determiner 101, but before the carbon dioxide leaks from the adsorption termination determiner 101 (about 20 minutes after the start of evaluation), the temperature difference ΔT ₁ was found to rise.

Thus, by determining the end of carbon dioxide adsorption based on the rise in the temperature difference ΔT ₁ , it is possible to reduce the time from when carbon dioxide starts to leak from the reaction vessel 106 to when the end of carbon dioxide adsorption is determined.

  The step of causing the gas flowing out from the gas outlet of the reaction vessel 106 to flow into the adsorption completion determination device 101 is the same as in the first embodiment of FIG.

The controller 120 determines the end of carbon dioxide adsorption in the reaction vessel 106 when the monitored temperature difference ΔT ₁ increases. After the completion of the adsorption, carbon dioxide is desorbed from the carbon dioxide adsorbent 105 in the same manner as in Embodiment 1 of FIG. Since the reactant 104 is also a material composed of at least one kind of amine substance, carbon dioxide is desorbed by heating or reducing the pressure of the adsorption completion judgment device 101. The reactant 104 heated or decompressed with the desorption of carbon dioxide is cooled until the temperature difference ΔT ₁ approaches zero. After the cooling, the reactant 104 can be used again to determine the end of the adsorption.

  According to such a configuration, the end of adsorption can be stably determined in accordance with the temperature of the gas inlet 131a of the processing target and the temperature of the reactant 104, regardless of the fluctuation of the gas to be processed. . In addition, by measuring the temperature while the temperature sensor 110 is in contact with the reactant 104, the temperature change of the reactant 104 can be accurately measured, and after the carbon dioxide starts to leak from the reaction vessel 106, It is possible to shorten the time until the end of the suction is determined.

(Embodiment 3)
FIG. 8 is a schematic configuration diagram of a carbon dioxide adsorption device 150C according to the third embodiment. 8, the same components as those in FIGS. 4 and 6 are denoted by the same reference numerals, and description thereof is omitted.

  In FIG. 8, temperature sensors 110a, 110b, and 110c, which are arranged in place of the temperature sensor 110, are arranged in an upstream portion, a middle stream portion, and a downstream portion inside the adsorption completion determination device 101 through which the gas to be treated flows, and each of them has an By directly measuring the temperatures of the three reactants 104 in contact with the agent 104, the temperature change can be accurately measured. As temperature sensors 110a, 110b, and 110c, those similar to temperature sensor 102 or 103 of the first embodiment can be used.

  The adsorption and desorption of carbon dioxide are performed alternately in the respective reaction vessels 106a and 106b, as in the first embodiment of FIG. The flow direction change valves 112a and 112c arranged on the outlet side of the reaction vessels 106a and 106b are controlled by the control unit 120 so that the gas flows into the adsorption end determiner 101 via the pipe 123 and to the pipe 124 or 125. Any one of the switching with the discharging direction is controlled. For example, in the process in which carbon dioxide is adsorbed in the reaction vessels 106a and 106b, respectively, the switching is controlled by the control unit 120 in a direction in which the gas flows into the adsorption completion determiner 101. In the step of desorbing carbon dioxide from 106b, switching is controlled by the control unit 120 in a direction to discharge the desorbed carbon dioxide to the pipes 124 and 125, respectively. The flow direction changing valve 112b is controlled by the control unit 120 in a direction in which the gas leaked from each of the adsorption of carbon dioxide alternately performed in the reaction vessels 106a and 106b flows into the adsorption end determination unit 101. .

Temperature _{T 102} of the processing gas inlet 131a of the suction end judgment unit 101 detected by the temperature sensor 102, temperature sensor 110a, 110b, the temperature _T 110a reactant 104 detected respectively _110c, T _110b, and _{T 110c} is It is input to the control unit 120.

The control unit 120 controls the temperature difference ΔT _a (= T _110a −T ₁₀₂ ), ΔT _b (= T _110b −T ₁₀₂ ), ΔT _c (= T _110c −) between the inlet gas of the adsorption completion determination unit 101 and the reactant 104. It monitors the change over time in T _102). When the end of adsorption is approaching and carbon dioxide leaks from the reaction vessels 106a and 106b to the adsorption end determiner 101, the temperature differences ΔT _a , ΔT _b and ΔT between the inlet gas of the adsorption end determiner 101 and the reactant 104. _c rises.

FIG. 9 shows a temperature difference ΔT _a between the gas inlet 131 a and the reactant 104 when the gas containing carbon dioxide (carbon dioxide concentration: 20%) is supplied to the adsorption termination determiner 101. 5) is a graph showing changes in ΔT _b (middle stream portion) and ΔT _c (downstream portion).

Reactant 104, to react sequentially from an upstream portion of the treated gas stream, first, (see point A in FIG. 9) Temperature difference [Delta] T _a of the upstream portion is increased, then increase the temperature difference [Delta] T _b of the middle portion (See point B in FIG. 9), and then the temperature difference ΔT _{c in the} downstream portion increased (see point C in FIG. 9).

FIG. 9 also shows a change in the concentration of carbon dioxide on the outlet side of the adsorption completion determiner 101, but before the carbon dioxide leaks from the adsorption completion determiner 101 (about 20 minutes after the start of evaluation), the temperature difference ΔT It was found that _a , ΔT _b , and ΔT _c increased sequentially.

Using the temperature differences ΔT _a , ΔT _b , and ΔT _c that sequentially rise, the adsorption termination determiner 101 does not perform desorption of carbon dioxide from the reactant 104 and cooling of the reactant 104 after each determination. (3) It is possible to determine the end of three suction operations. The control unit 120 sequentially determines the end of adsorption based on the temperature differences ΔT _a , ΔT _b , and ΔT _c , counts the number of determinations, and determines the temperature differences ΔT _a , ΔT _b , and ΔT _c according to the count number. And the start of desorption of carbon dioxide in the reactant 104 are controlled.

  Hereinafter, the determination of the end of three suctions will be specifically described.

  The control unit 120 controls the flow direction change valves 112, 112a, and 112b, and switches the valves 112, 112a, and 112b such that the gas to be processed flows through the reaction vessel 106a to the pipe 123 and the adsorption completion determination unit 101. Thus, the carbon dioxide of the gas to be treated is adsorbed by the carbon dioxide adsorbent 105.

Then, the control unit 120, at the suction end determination unit 101, when the temperature difference [Delta] T _a of the upstream side being monitored has increased, it is determined first adsorption completion of carbon dioxide in the reaction vessel 106a, the flow path By controlling the direction changing valve 112a, the flow path is switched from the pipe 123 to the pipe 124. The carbon dioxide desorbed from the carbon dioxide adsorbent 105 of the reaction vessel 106a is discharged to a pipe 124.

After that, the control unit 120 switches the valves 112, 112c, and 112b so that the gas to be processed flows through the reaction vessel 106b to the pipe 123 and the adsorption completion determination unit 101. After the adsorption step of the carbon dioxide in the reaction vessel 106b, when the temperature difference [Delta] T _b of midstream side being monitored increases, determining a second suction end of the carbon dioxide in the reaction vessel 106b, the piping the flow path 123 To the direction of the pipe 125. The carbon dioxide desorbed from the reaction vessel 106b is discharged to the pipe 125.

Thereafter, the control unit 120 switches the valves 112, 112a, and 112b so that the gas to be processed flows through the reaction vessel 106a and flows to the pipe 123 and the adsorption completion determination unit 101. Again, after the adsorption step of the carbon dioxide in the reaction vessel 106a, when the temperature difference [Delta] T _c on the downstream side being monitored increases, it determines third suction end of the carbon dioxide in the reaction vessel 106b, the flow path The direction is switched from the pipe 123 to the pipe 124. The carbon dioxide desorbed from the reaction vessel 106a is discharged to the pipe 124.

  After counting the end of adsorption three times, the end-of-adsorption determiner 101 also desorbs carbon dioxide adsorbed on the reactant 104. The carbon dioxide desorbed from the adsorption termination determiner 101 is discharged to the pipe 123. After the carbon dioxide is desorbed, the reactant 104 is cooled in the same manner as in Embodiment 2, and can be used again to determine the end of adsorption.

In the adsorption end determiner 101, the determination of the end of adsorption is sequentially counted three times from the temperature difference ΔT _a to the temperature difference ΔT _{b and the} temperature difference ΔT _c . By performing the desorption of carbon dioxide, the exchange frequency of the reactant 104 can be reduced, which can contribute to cost reduction.

  In the third embodiment, the temperature sensors 110a, 110b, and 110c are arranged at three locations from the upstream portion to the downstream portion inside the adsorption completion determiner 101, so that the temperature change of the reactant 104 at different locations can be sequentially measured. However, the number of sensors may be increased or decreased depending on the size of the adsorption end determiner 101 or the amount of the reactant 104 charged. In addition, a mechanism is provided in which the temperature sensor moves from the upstream portion to the downstream portion inside the adsorption end determiner 101 through which the gas to be treated flows, and the temperature sensor can be moved to sequentially measure the temperature change of the reactant 104 at different locations. You may do so. In short, it suffices that the temperature can be measured at a plurality of locations (in other words, a plurality of locations along the direction from the gas inlet to the gas outlet to the gas to be processed) from the upstream portion to the downstream portion inside the adsorption completion determination device 101. For this purpose, the temperature sensors may be three temperature sensors as in the third embodiment, one movable temperature sensor as in this modification, or one fixed temperature sensor. One of the sensors may be a movable temperature sensor, or a total of two temperature sensors.

  According to this configuration, regardless of the variation of the gas to be treated, the temperature of the upstream side near the gas to be treated 131a, the temperature on the midstream side, and the temperature of the downstream side near the gas to be treated 131b of the adsorption completion determination device 101 are determined. The end of the adsorption can be determined stably according to the temperature. In addition, by measuring the temperature in a state where the temperature sensors 110a, 110b, and 110c are in contact with the reactant, the temperature change can be accurately measured, and after the carbon dioxide starts leaking from the reaction vessels 106a and 106b. In addition, it is possible to shorten the time until the end of adsorption is determined. Further, the temperature sensors 110a, 110b, and 110c are disposed at three locations from the upstream portion to the downstream portion of the adsorption completion determination device 101, and the completion of carbon dioxide adsorption is sequentially determined, thereby reducing the frequency of replacement of the reactant 104. It can contribute to cost reduction.

  In addition, by appropriately combining any of the above-described various embodiments or modifications, the effects of the respective embodiments or modifications can be achieved. In addition, a combination of the embodiments or a combination of the examples or a combination of the embodiment and the example is possible, and a combination of the features in the different embodiments or the examples is also possible.

  The method for determining the end of adsorption of the carbon dioxide adsorption device and the carbon dioxide adsorption device according to the aspect of the present invention can perform stable determination without receiving a change in the gas to be treated, as compared with the conventional method for determining the end of adsorption. become. In addition, the above aspect of the present invention allows a carbon dioxide adsorbent to be used more efficiently, leading to a reduction in the cost of separating and recovering carbon dioxide. Such a reduction in the cost of separating and recovering carbon dioxide is widely used as a means for reducing carbon dioxide, and may lead to improvement of the global environment.

12 ... reaction vessel 14 ... adsorbent 18 ... reaction vessel 22 ... two-way valve 24 ... discharge valve 28 ... recovery valve 30 ... carbon dioxide concentration sensor 101, 101a, 101b ··· Adsorption termination determiners 102, 102a and 102b ··· Inlet side temperature sensors 103, 103a and 103b ··· Outlet side temperature sensors 104 ··· Reactants 105 ··· Carbon dioxide adsorbents 106 and 106a , 106b ... reaction vessel 107 ... gas on-off valve 108 ... blower pump 109 ... carbon dioxide containing gas introduction part 110, 110a, 110b, 110c ... reactant temperature sensor 111 ... Process gas flows 112, 112a, 112b, 112c ... flow direction changing valve 120 ... control unit 120a ... calculation unit 120b ... operation control Parts 121, 122, 123, 124, 125... Piping 131 a... Gas-to-be-processed gas inlet 131 b... Gas-to-be-processed gas outlet 136 a. ··· Carbon dioxide adsorption device ΔT ··· inlet / outlet gas temperature differences ΔT ₁ , ΔT _a , ΔT _b , ΔT _c ··· temperature difference T ₁₀₂ between inlet gas and reactant · temperature T ₁₀₃ on inlet side Outlet temperature T ₁₁₀ , T _110a , T _110b , T _110c ... temperature of reactants

Claims (8)

There is a gas inlet and a gas outlet, and a gas to be treated containing carbon dioxide is introduced into the reaction vessel from the gas inlet of the reaction vessel filled with a carbon dioxide adsorbent, and the carbon dioxide is introduced into the reaction vessel. In the method of adsorbing carbon dioxide by a carbon dioxide adsorbing device that performs carbon adsorption with the carbon dioxide adsorbent,
A first step of contacting the gas to be treated and the adsorbent in the reaction vessel to adsorb the carbon dioxide of the gas to be treated to the adsorbent;
A second step of causing the gas flowing out of the gas outlet of the reaction vessel to flow into an adsorption termination determiner;
A third step of measuring the temperature of the gas-to-be-processed inlet and the temperature of the gas-to-be-processed outlet of the adsorption completion determiner in which the reactant with carbon dioxide is filled,
A fourth step of determining the end of adsorption according to the temperature of the gas to be treated inlet and the temperature of the gas to be treated outlet of the adsorption end determiner.
A method for determining the end of adsorption of a carbon dioxide adsorption device.   2. The method for determining the end of adsorption of the carbon dioxide adsorption device according to claim 1, wherein the temperature of the target gas outlet is higher than the temperature of the target gas inlet of the adsorption end determiner. 3.   The method according to claim 1, wherein the reactant is an amine compound.   The reactant is an amine selected from the group consisting of aliphatic primary, secondary and tertiary amines, and polyamines, polyimines, cyclic amines, amidine compounds, hindered amines, amino-siloxane compounds, amino acids, and combinations thereof. The method according to claim 3, wherein the method is a compound. There is a gas inlet and a gas outlet, and a gas to be treated containing carbon dioxide is introduced into the reaction vessel from the gas inlet of the reaction vessel filled with a carbon dioxide adsorbent, and the carbon dioxide is introduced into the reaction vessel. In the method of adsorbing carbon dioxide by a carbon dioxide adsorbing device that performs carbon adsorption with the carbon dioxide adsorbent,
A first step of contacting the gas to be treated and the adsorbent in the reaction vessel to adsorb the carbon dioxide of the gas to be treated to the adsorbent;
A second step of causing the gas flowing out of the gas outlet of the reaction vessel to flow into an adsorption termination determiner;
A third step of measuring the temperature of the gas inlet and the temperature of the reactant of the adsorption completion determiner filled with the reactant with carbon dioxide,
A fourth step of determining the end of adsorption according to the temperature of the gas inlet and the temperature of the reactant of the adsorption end determiner.
A method for determining the end of adsorption of a carbon dioxide adsorption device. There is a treated gas inlet and a treated gas outlet which are directly connected by piping at the gas outlet of the reaction vessel, and an adsorption completion determiner filled with a reactant with carbon dioxide inside,
A temperature sensor arranged at each of the to-be-treated gas inlet and the to-be-treated gas outlet of the adsorption termination determiner, for measuring the temperature of the to-be-treated gas,
A carbon dioxide adsorption device comprising: a control unit for judging the end of adsorption based on the temperature of the inlet of the gas to be treated and the temperature of the outlet of the gas to be treated of the adsorption end determiner of the gas to be treated, measured by the temperature sensor. . There is a treated gas inlet and a treated gas outlet which are directly connected by piping at the gas outlet of the reaction vessel, and an adsorption completion determiner filled with a reactant with carbon dioxide inside,
Temperature sensors for measuring the temperature of the gas inlet and the reactant of the adsorption end determiner,
A carbon dioxide adsorption device comprising: a control unit that judges the end of adsorption based on the temperature of the gas inlet of the gas to be processed and the temperature of the reactant measured by the temperature sensor at the inlet of the gas to be processed determination unit.   The carbon dioxide adsorption device according to claim 7, wherein the temperature sensor that measures the temperature in the adsorption termination determiner performs temperature measurement at a plurality of locations along the direction from the gas-to-be-processed gas inlet to the gas-to-be-processed gas outlet. .

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