Abstract: A CO2 recovery unit includes a CO2 absorber that brings a gas having a low CO2 concentration into countercurrent contact with a CO2 absorbent to remove CO2 from the gas. The CO2 recovery unit further includes a first absorbent circulation line that supplies a CO2 absorbent from a first CO2 absorption section as a first circulation solution to an upper side of a first CO2 absorption section; a second absorbent circulation line that supplies a CO2 absorbent from a second CO2 absorption section as a second circulation solution to an upper side of a second CO2 absorption section; and an absorbent discharge line that discharges a part of the first circulation solution from the first absorbent circulation line and supply the part of the first circulation solution as a discharged solution to the second absorbent circulation section.

Abstract: A reduction device, an acid gas recovery device, a recovery device collector, and a first removed substance returning line are provided. The reduction device is configured to perform a reduction process to turn iron oxide to reduced iron by adding a reducing agent. The acid gas recovery device is configured to recover CO2 being acid gas with CO2 absorbing liquid being acid gas absorbing liquid from exhaust gas containing at least powder-shaped iron-based solid substances and the acid gas, which are discharged from the reduction device. The recovery device collector is configured to collect the iron-based solid substance contained in the absorbing liquid with a filter. The iron-based solid substances collected by the recovery device collector are removed, and removed substances containing the removed iron-based solid substances are returned to the reduction device side through the first removed substance returning line.

Abstract: A reduction device, an acid gas recovery device, a recovery device collector, and a first removed substance returning line are provided. The reduction device is configured to perform a reduction process to turn iron oxide to reduced iron by adding a reducing agent. The acid gas recovery device is configured to recover CO2 being acid gas with CO2 absorbing liquid being acid gas absorbing liquid from exhaust gas containing at least powder-shaped iron-based solid substances and the acid gas, which are discharged from the reduction device. The recovery device collector is configured to collect the iron-based solid substance contained in the absorbing liquid with a filter. The iron-based solid substances collected by the recovery device collector are removed, and removed substances containing the removed iron-based solid substances are returned to the reduction device side through the first removed substance returning line.

Abstract: A CO2 recovery device includes: a CO2 absorption tower in which CO2 included in an exhaust gas is absorbed by a CO2 absorption liquid; and a CO2 absorption liquid regeneration tower that heats and regenerates the CO2 absorption liquid that has absorbed CO2. The CO2 absorption liquid regeneration tower includes: a main body part in which the CO2 absorption liquid is temporarily stored; a boot part provided downward from a tank end of the main body part, having a relatively smaller capacity than the main body part; a flowmeter provided to the boot part, and measuring the liquid surface level of the CO2 absorption liquid that changes between the main body part and the boot part; and a control device controlling the liquid surface level of the CO2 absorption liquid between the main body part and the boot part on the basis of the measurement result of the flowmeter.

Abstract: A CO2 recovery device includes: a CO2 absorption tower in which CO2 included in an exhaust gas is absorbed by a CO2 absorption liquid; and a CO2 absorption liquid regeneration tower that heats and regenerates the CO2 absorption liquid that has absorbed CO2. The CO2 absorption liquid regeneration tower includes: a main body part in which the CO2 absorption liquid is temporarily stored; a boot part provided downward from a tank end of the main body part, having a relatively smaller capacity than the main body part; a flowmeter provided to the boot part, and measuring the liquid surface level of the CO2 absorption liquid that changes between the main body part and the boot part; and a control device controlling the liquid surface level of the CO2 absorption liquid between the main body part and the boot part on the basis of the measurement result of the flowmeter.

Abstract: A gas-liquid contactor is obtained by including a header pipe for supplying washing water, in a direction perpendicular to a vertical axis direction, the header pipe being disposed above a packed bed contacting section through which exhaust gas moves upward and passes; and spray nozzles for discharging spray water, the nozzles being disposed, in an upward orientation, with predetermined intervals on the header pipe. The spray water that has been discharged from the spray nozzles is supplied at a low liquid flow rate. The discharged spray water becomes a liquid film and falls downward along the surface of the header pipe, and then falls and spreads in the packed bed contacting section, so that the washing water is made to contact the exhaust gas moving upward through the packed bed contacting section. Accordingly, the washing water is used to clear and remove water-soluble substances contained in the exhaust gas.

Abstract: A CO2 recovery device includes: a CO2 absorption tower in which CO2 included in an exhaust gas is absorbed by a CO2 absorption liquid; and a CO2 absorption liquid regeneration tower that heats and regenerates the CO2 absorption liquid that has absorbed CO2. The CO2 absorption liquid regeneration tower includes: a main body part in which the CO2 absorption liquid is temporarily stored; a boot part provided downward from a tank end of the main body part, having a relatively smaller capacity than the main body part; a flowmeter provided to the boot part, and measuring the liquid surface level of the CO2 absorption liquid that changes between the main body part and the boot part; and a control device controlling the liquid surface level of the CO2 absorption liquid between the main body part and the boot part on the basis of the measurement result of the flowmeter.

Abstract: A CO2 recovery device includes: a CO2 absorption tower in which CO2 included in an exhaust gas is absorbed by a CO2 absorption liquid; and a CO2 absorption liquid regeneration tower that heats and regenerates the CO2 absorption liquid that has absorbed CO2. The CO2 absorption liquid regeneration tower includes: a main body part in which the CO2 absorption liquid is temporarily stored; a boot part provided downward from a mirror surface part of the main body part, having a relatively smaller capacity than the main body part; a flowmeter provided to the boot part, and measuring the liquid surface level of the CO2 absorption liquid that changes between the main body part and the boot part; and a control device controlling the liquid surface level of the CO2 absorption liquid between the main body part and the boot part on the basis of the measurement result of the flowmeter.

Abstract: A composite amine absorbent is an absorbent dissolved in water for absorbing CO2 or H2S in gas, or both of them, which comprises: 1) at least one amine compound, and 2) a disulfide compound as an oxidative degradation inhibitor for the absorbent, wherein the disulfide compound is a compound represented by the following Chemical Formula (I). R1—S—S—R2??(I) in the formula, or R1 or R2 is any one of an alkyl group with 1 to 4 carbon atoms, a hydroxyethyl group, a carhoxyethyl group, a cyclohexyl group, and a dibutylthiocarbamoyl group.

Abstract: A gas-liquid contactor is obtained by including a header pipe for supplying washing water, in a direction perpendicular to a vertical axis direction, the header pipe being disposed above a packed bed contacting section through which exhaust gas moves upward and passes; and spray nozzles for discharging spray water, the nozzles being disposed, in an upward orientation, with predetermined intervals on the header pipe. The spray water that has been discharged from the spray nozzles is supplied at a low liquid flow rate. The discharged spray water becomes a liquid film and falls downward along the surface of the header pipe, and then falls and spreads in the packed bed contacting section, so that the washing water is made to contact the exhaust gas moving upward through the packed bed contacting section. Accordingly, the washing water is used to clear and remove water-soluble substances contained in the exhaust gas.