Carbon dioxide capture system

Abstract

To provide a carbon dioxide recovery system which can suppress energy consumption.SOLUTION: A control device 17 applies an adsorption potential to a portion between an action electrode and a counter electrode only for an adsorption time corresponding to a target carbon dioxide adsorption amount being an adsorption amount of carbon dioxide that can be adsorbed by an adsorbent such that the adsorbent adsorbs the carbon dioxide in the time of execution of an adsorption mode. The control device 17 applies a desorption potential to a portion between the action electrode and the counter electrode only for a recovery time corresponding to a recovery amount in the time of execution of a desorption mode of desorbing the carbon dioxide adsorbed by the adsorbent. At this time, the control device 17 acquires the desorption time associated with a carbon dioxide desorption amount equivalent to the target carbon dioxide recovery amount in desorption amount change map data as the optimum desorption time. The control device 17 applies the desorption potential only for the optimum desorption time in the desorption mode.SELECTED DRAWING: Figure 1

Claims

1. A carbon dioxide capture system that recovers carbon dioxide from a mixed gas containing carbon dioxide by an electrochemical reaction, A carbon dioxide capture tank (16) for storing the captured carbon dioxide, An electrochemical cell having a working electrode containing an adsorbent material capable of adsorbing carbon dioxide, and a counter electrode paired with the working electrode, and a housing for housing the electrochemical cell, wherein the mixed gas is supplied to the inside of the housing, at least one recovery unit (12), A sensor (15) for detecting the amount of carbon dioxide recovered from the recovery device to the carbon dioxide recovery tank, The control device (17) controls whether, during the execution of the adsorption mode in which carbon dioxide is adsorbed, a first potential is applied between the working electrode and the counter electrode only for an adsorption time associated with a target adsorption amount, which is the amount of carbon dioxide that the adsorbent can adsorb, so that the adsorbent adsorbs carbon dioxide, or whether, during the execution of the desorption mode in which the carbon dioxide adsorbed by the adsorbent is desorbed, a second potential is applied between the working electrode and the counter electrode only for a recovery time corresponding to the recovery amount, and acquires the amount of carbon dioxide recovered in the carbon dioxide recovery tank, which is detected via the sensor, as the target adsorption amount. The control device uses the optimal desorption time to obtain an amount of carbon dioxide desorbed equivalent to the amount of carbon dioxide recovered in the carbon dioxide recovery tank, which is the detection result via the sensor, to acquire the optimal desorption time, and stores desorption amount change data that associates the amount of desorption with the desorption time to obtain the amount of desorption, generated to satisfy the relationship between the amount of carbon dioxide desorbed and the amount of carbon dioxide desorbed as the desorption time progresses. A carbon dioxide recovery system comprising: a control device that acquires the desorption time associated with the desorption amount equivalent to the recovery amount or the target adsorption amount in the desorption amount change data as the optimal desorption time, and applies the second potential only during the optimal desorption time in the desorption mode.

2. The control device, after the optimal desorption time has elapsed via the application of the second potential, starts driving the pump to execute a recovery mode in which the desorbed carbon dioxide is recovered from the recovery device to the carbon dioxide recovery tank, and stops driving the pump when the amount recovered reaches the target amount, the carbon dioxide recovery system according to claim 1.

3. The control device executes the recovery mode to generate the data of the change in the amount of desorption, The carbon dioxide recovery system according to claim 2, wherein in the recovery mode, the pump is driven to obtain the amount of carbon dioxide recovered during a provisional desorption time set to achieve the target amount of desorption, the acquired amount of recovery is considered as the amount of desorption, and data is generated showing the relationship between the amount of desorption and the desorption time such that the relationship between the amount of desorption and the provisional desorption time is satisfied with the relationship between the increase in the amount of desorption as the desorption time progresses.

4. The carbon dioxide recovery system according to claim 3, wherein the target amount of desorption corresponds to the amount of carbon dioxide desorbed before the execution of the recovery mode.

5. The carbon dioxide recovery system according to claim 3, wherein the control device updates the target adsorption amount to a smaller value at predetermined intervals and updates the optimal desorption time to a shorter value in conjunction with the update of the target adsorption amount.

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