Abstract: An absorber of a carbon dioxide capture system according to an embodiment includes: a release region for releasing carbon dioxide from an absorbing liquid supplied from a stripper; and a second gas-liquid contact unit to which carbon dioxide released in the release region is supplied together with exhaust gas discharged from a first gas-liquid contact unit. The absorbing liquid having released the carbon dioxide therefrom in the release region is supplied to the second gas-liquid contact unit by an absorbing liquid supply device. The absorbing liquid having passed through the second gas-liquid contact unit is guided to the first gas-liquid contact unit while bypassing the release region. The second gas-liquid contact unit brings the exhaust gas and the absorbing gas into contact with each other so as to cause the carbon dioxide contained in the exhaust gas to be absorbed in the absorbing liquid.

Abstract: A carbon dioxide capture system includes: a washing unit which uses cleaning water to clean absorption unit exhaust gas or stripping unit exhaust gas; and a gas-liquid separation device which allows condensed water generated by cooling washing unit exhaust gas to be separated from the washing unit exhaust gas. The condensed water is mixed into the cleaning water by a condensed water line. If the amount of the cleaning water becomes more than a predetermined amount, the cleaning water is mixed into an absorbing liquid by a cleaning water line. A controller controls a condensed water valve.

Abstract: An absorber of a carbon dioxide capture system according to an embodiment includes: a release region for releasing carbon dioxide from an absorbing liquid supplied from a stripper; and a second gas-liquid contact unit to which carbon dioxide released in the release region is supplied together with exhaust gas discharged from a first gas-liquid contact unit. The absorbing liquid having released the carbon dioxide therefrom in the release region is supplied to the second gas-liquid contact unit by an absorbing liquid supply device. The absorbing liquid having passed through the second gas-liquid contact unit is guided to the first gas-liquid contact unit while bypassing the release region. The second gas-liquid contact unit brings the exhaust gas and the absorbing gas into contact with each other so as to cause the carbon dioxide contained in the exhaust gas to be absorbed in the absorbing liquid.

Abstract: In one embodiment, a carbon dioxide capturing system includes an absorber to discharge an absorption liquid having absorbed carbon dioxide, a regenerator to discharge the absorption liquid having released the carbon dioxide, a first line to introduce the absorption liquid discharged from the absorber to the regenerator, a second line to introduce the absorption liquid discharged from the regenerator to the absorber, and a heat exchanger to exchange heat between absorption liquids flowing in the first and second lines. The system further includes a bypass line to branch from the first line between the absorber and the heat exchanger and introduce the absorption liquid to the regenerator without passing through the heat exchanger, a valve on the bypass line, an instrument to measure a value indicating a state of the regenerator, and a controller to control a degree of opening of the valve based on the measured value.

Abstract: A carbon dioxide capture system according to an embodiment includes an absorber, a stripper, and a heater. The absorber includes a first cleaning unit and a second cleaning unit. The first cleaning unit uses first cleaning liquid to clean combustion exhaust gas discharged from a carbon dioxide capturer and captures amine flowing together with the combustion exhaust gas. The second cleaning unit uses second cleaning liquid to clean the combustion exhaust gas discharged from the first cleaning unit and captures amine flowing together with the combustion exhaust gas. The heater heats the first cleaning liquid to a temperature higher than the temperature of an upper portion of the carbon dioxide capturer and of the second cleaning liquid.

Abstract: A carbon dioxide capture apparatus according to an embodiment includes an absorber and a stripper. The liquid level of the absorbing liquid within the absorber is measured by an absorber level gauge. A regulating liquid that contains water and is used to control the proportion of water contained in the absorbing liquid is stored in a regulating liquid tank. The flow rate of the regulating liquid to be supplied from the regulating liquid tank to the absorber or the stripper is controlled by a regulating liquid control valve. A controller controls the opening degree of the regulating liquid control valve based on the liquid level of the absorbing liquid measured by the absorber level gauge.

Abstract: In a carbon dioxide separation and capture apparatus according to an embodiment, a control device calculates a flow rate range of a carbon dioxide gas based on the concentration of the carbon dioxide gas and an output range of a blower. The control device determines a flow rate of the carbon dioxide gas in which the sum of energy is the least based on relationships, corresponding to a preset target amount of carbon dioxide gas to be captured, between a flow rate of the carbon dioxide gas, and sum of energy obtained by summing the amount of heat to be supplied by a heating medium from the external, power of the blower and power of a pump. The control device controls output of the blower, an opening degree of the first flow rate control valve, and an opening degree of the second flow rate control valve.

Abstract: According to one embodiment, a carbon dioxide recovery device includes an absorption tower configured to cause carbon dioxide-containing gas to come in contact with absorbing solution and to generate rich solution absorbing the carbon dioxide, a regeneration tower configured to heat the rich solution, to disperse steam containing the carbon dioxide, and to generate lean solution from which the carbon dioxide is removed, a heat exchanging device configured to exchange heat between the lean solution and the rich solution, to supply the rich solution after the heat exchange to the regeneration tower, and to supply the lean solution after the heat exchange to the absorption tower, and a cooling device configured to cool a part of the rich solution discharged from a first place of the absorption tower and to supply the cooled rich solution to a second place higher than the first place of the absorption tower.

Abstract: The CO2 recovery apparatus 10A includes: an absorption tower 11 in which a discharge gas 21 is contacted with a second lean solution 22B to allow the second lean solution 22B to absorb CO2; a temperature regulator 12 in which a first rich solution 23A discharged from the absorption tower is heated or cooled to allow the first rich solution 23A to be a solution in which a precipitate containing the reaction accelerator is dispersed; a phase separator 13 in which a second rich solution 23B passed through the temperature regulator 12 is separated into an amino group-containing compound rich phase 31 and a reaction accelerator rich phase 32; a regeneration tower 15 in which a third rich solution 23C is regenerated; and a solution mixing line L13A through which a reaction accelerator rich solution 34 is supplied to a first lean solution 22A discharged from the regeneration tower 15.

Abstract: In one embodiment, a carbon dioxide capturing system includes an absorption tower to bring a gas containing carbon dioxide into contact with an absorbing liquid to discharge the absorbing liquid which has absorbed the carbon dioxide and discharge the gas whose carbon dioxide concentration is reduced. The system includes a regeneration tower to release the carbon dioxide from the absorbing liquid to discharge the absorbing liquid whose carbon dioxide concentration is reduced and discharge a gas containing the carbon dioxide. The system includes a first absorbing liquid component washing apparatus to cool the gas which is discharged from the absorption or regeneration tower and has passed through an absorption or regeneration tower condenser to condense or sublime an absorbing liquid component in the gas and remove a liquid or solid product generated by the condensation or sublimation of the absorbing liquid component by using a washing liquid.

Abstract: An acid gas absorbent according to an embodiment includes at least one kind of secondary amine compound represented by the following general formula (1). In the above-described formula (1), R1 indicates a cyclopenthyl group or a cyclohexyl group in which a part of a hydrogen atom may be substituted by a substituted or non-substituted alkyl group having 1 to 3 carbon atoms, R2 and R3 each indicate an alkylene group having 2 to 4 carbon atoms, and, R2 and R3 may each be the same or different, and be a straight chain or have a side chain.

Abstract: A gas collection method comprises contacting a gas mixture including a weak acidic gas and a strong acidic gas with amine solution that absorbs a first portion of the gas mixture. After this first contacting step the gas mixture is contacted with amine solution that absorbs a second portion of the mixture. The amine solution after the second contacting step is heated to discharge at least some portion of the weak acid gas component absorbed therein. The method also includes adding an alkaline compound to the amine solution to generate a salt by reaction with the strong acidic component. The salt is separated from the amine solution and this amine solution can be used in the second contacting step.

Abstract: In one embodiment, a carbon dioxide capturing system includes an absorption tower configured to bring a treatment target gas containing carbon dioxide into contact with an absorption liquid, and to discharge the absorption liquid having absorbed the carbon dioxide. The system further includes a regeneration tower configured to make the absorption liquid discharged from the absorption tower dissipate the carbon dioxide, and to discharge the absorption liquid having dissipated the carbon dioxide. The system further includes a treatment target gas line configured to introduce the treatment target gas into the absorption tower, a first introduction module configured to introduce a first gas having a higher carbon dioxide concentration than the treatment target gas into the treatment target gas line, and a second introduction module configured to introduce a second gas having a lower carbon dioxide concentration than the treatment target gas into the treatment target gas line.

Abstract: In accordance with an embodiment, a carbon dioxide capturing apparatus includes a first absorbing unit, a regeneration unit, a water washing capturing unit, and a pre-amine capturing unit. The first absorbing unit brings a gas containing carbon dioxide into contact with an absorbing liquid containing an amine compound, and discharges the absorbing liquid which has absorbed carbon dioxide as a rich liquid. The regeneration unit releases a carbon dioxide gas from the rich liquid sent from the first absorbing unit. The water washing capturing unit captures the amine compound entrained in a decarbonated treatment gas sent from the first absorbing unit. The pre-amine capturing unit receives part of the rich liquid from the first absorbing unit, and traps the amine compound entrained in the decarbonated treatment gas by bringing the decarbonated treatment gas from the first absorbing unit into countercurrent contact with the part of the rich liquid.

Abstract: In one embodiment, a carbon dioxide separating and recovering system includes an absorption tower to cause carbon dioxide to be absorbed in an absorbing solution, a regeneration tower to release the carbon dioxide from the absorbing solution, and at least one measuring apparatus to measure an ultrasound propagation speed in the absorbing solution. Each of the at least one measuring apparatus calculates a dissolved carbon dioxide concentration in the absorbing solution, based on a temperature measured by a temperature measuring unit, the ultrasound propagation speed measured by an ultrasound propagation speed measuring unit, and a correlation expression which shows a relationship between the dissolved carbon dioxide concentration and the ultrasound propagation speed in the absorbing solution, and is changed according to the temperature of the absorbing solution.

Abstract: According to one embodiment, a carbon dioxide recovery device includes an absorption tower configured to cause carbon dioxide-containing gas to come in contact with absorbing solution and to generate rich solution absorbing the carbon dioxide, a regeneration tower configured to heat the rich solution, to disperse steam containing the carbon dioxide, and to generate lean solution from which the carbon dioxide is removed, a heat exchanging device configured to exchange heat between the lean solution and the rich solution, to supply the rich solution after the heat exchange to the regeneration tower, and to supply the lean solution after the heat exchange to the absorption tower, and a cooling device configured to cool a part of the rich solution discharged from a first place of the absorption tower and to supply the cooled rich solution to a second place higher than the first place of the absorption tower.

Abstract: An acid gas absorbent comprising at least one type of diamine compound represented by the following general formula (1), R1R2N—(CHR3)n—CH2—NR4R5??(1), where R1, R2, R4 and R5 represent any of: a cyclic alkyl group having carbon number from 3 to 6; an alkyl group having carbon number from 1 to 4; a hydroxyalkyl group; and a hydrogen atom, R3 represents any of: the hydrogen atom; a methyl group; and an ethyl group, “n” represents an integer number of 1 or 2, at least one of two amino groups is a secondary amino group, both of the two amino groups are groups other than a primary amino group.

Abstract: In one embodiment, a carbon dioxide capturing system includes an absorption tower to bring a gas containing carbon dioxide into contact with an absorbing liquid to discharge the absorbing liquid which has absorbed the carbon dioxide and discharge the gas whose carbon dioxide concentration is reduced. The system includes a regeneration tower to release the carbon dioxide from the absorbing liquid to discharge the absorbing liquid whose carbon dioxide concentration is reduced and discharge a gas containing the carbon dioxide. The system includes a first absorbing liquid component washing apparatus to cool the gas which is discharged from the absorption or regeneration tower and has passed through an absorption or regeneration tower condenser to condense or sublime an absorbing liquid component in the gas and remove a liquid or solid product generated by the condensation or sublimation of the absorbing liquid component by using a washing liquid.

Abstract: There is provided an acid gas absorbent having excellent performance of absorbing acid gas such as carbon dioxide, and an acid gas removal device and an acid gas removal method using the acid gas absorbent. An acid gas absorbent of an embodiment contains at least one type of tertiary amine compound represented by the following general formula (1). (In the above formula (1), the cycle A represents a cyclic structure whose carbon number is not less than 3 nor more than 8. R1, R2 and R3 each represent an alkyl group whose carbon number is 1 to 4, and R4 represents a hydroxyalkyl group. R1 and R2 are groups coupled to carbon atoms adjacent to a carbon atom forming the cycle A and coupled to a nitrogen atom.

Abstract: In accordance with an embodiment, a carbon dioxide capturing device includes an absorption tower, a regeneration tower, and a cooling unit. A gas containing carbon dioxide and a lean liquid is introduced to the absorption tower which brings the gas and the lean liquid into contact with each other to generate a rich liquid. The regeneration tower generates a lean liquid by diffusing vapor containing carbon dioxide from the rich liquid from the absorption tower, and then returns the lean liquid to the absorption tower. The cooling unit cools at least one of the gas, the lean liquid, and the rich liquid. The cooling unit includes first and second coolers connected in series to each other, by first and second cooling mediums, respectively. The first cooling medium is generated outside the device without using power for cooling in the device. The first cooler is located upstream of the second cooler.