CO2 recovery unit and CO2 recovery method

Patent metadata

Field	Value
Publication number	US-10213726-B2
Application number	US-201715397433-A
Country	US
Kind code	B2
Filing date	Jan 3, 2017
Priority date	Jul 10, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

A CO2 recovery unit includes a CO2 absorber in which a gas containing CO2 contacts a CO2-absorbing solution that absorbs the CO2 in the gas; a CO2-absorbing solution regenerator that heats the CO2-absorbing solution that has absorbed the CO2, releases the CO2 from the CO2-absorbing solution, and regenerates the CO2-absorbing solution; and at least one of a CO2 recovery rate controller that controls a difference between an actual measured value and a target value of a recovery rate of the CO2 to be within a predetermined range; and a CO2 recovery amount controller that controls a difference between an actual measured value and a target value of a recovery amount of CO2 to be within a predetermined range.

First claim

What is claimed is:

1. A CO 2 recovery unit comprising:
a CO 2 absorber in which a gas containing CO 2 contacts a CO 2 -absorbing solution that absorbs the CO 2 in the gas;
a CO 2 -absorbing solution regenerator that heats the CO 2 -absorbing solution that has absorbed the CO 2 , releases the CO 2 from the CO 2 -absorbing solution, and regenerates the CO 2 -absorbing solution; and
at least one of:
a CO 2 recovery rate controller that controls a difference between an actual measured value and a target value of a recovery rate of the CO 2 to be within a predetermined range by changing, based on the actual measured value and the target value of the CO 2 recovery rate, a circulation amount of the CO 2 -absorbing solution to be supplied to the CO 2 absorber and a supply amount of saturated steam to be supplied to a regeneration heater of the CO 2 -absorbing solution regenerator; and
a CO 2 recovery amount controller that controls a difference between an actual measured value and a target value of a recovery amount of CO 2 to be within a predetermined range by changing, based on the actual measured value and the target value of the CO 2 recovery amount, the circulation amount of the CO 2 -absorbing solution to be supplied to the CO 2 absorber and the supply amount of the saturated steam to be supplied to the regeneration heater of the CO 2 -absorbing solution regenerator;
wherein the CO 2 recovery rate controller controls the CO 2 recovery rate through a proportional calculation and an integration calculation based on the difference between the actual measured value and the target value of the CO 2 recovery rate.

2. The CO 2 recovery unit according to claim 1 ,
wherein the CO 2 recovery amount controller controls the CO 2 recovery amount through a proportional calculation and an integration calculation based on the difference between the actual measured value and the target value of the CO 2 recovery amount.

3. The CO 2 recovery unit according to claim 1 ,
wherein the CO 2 recovery rate controller operates in one of:
a first control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled at any time, and
a second control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled for each predetermined period, and

wherein the CO 2 recovery amount controller operates in one of:
a first control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled at any time, and
a second control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled for each predetermined period.

4. The CO 2 recovery unit according to claim 3 ,
wherein one of the CO 2 recovery rate controller and the CO 2 recovery amount controller operates in the first control mode, and the other operates in the second control mode.

5. The CO 2 recovery unit according to claim 1 ,
wherein the CO 2 recovery rate controller operates in a first control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled at any time,
wherein the CO 2 recovery amount controller operates in a first control mode where the circulation amount and the supply amount of the saturated steam are calculated and controlled at any time, and
wherein one of the CO 2 recovery amount controller and the CO 2 recovery rate controller is provided with a dead band.

Assignees

• Mitsubishi Heavy Ind Eng Ltd

Inventors

• Nakagawa Yosuke
• Shimada Daisuke
• Tsujiuchi Tatsuya

Classifications

• B01D53/1425

  Regeneration of liquid absorbents · CPC title

• B01D53/62

  Carbon oxides · CPC title

• B01D2252/20478

  Alkanolamines · CPC title

• B01D53/1412 Primary

  Controlling the absorption process · CPC title

• B01D53/1475

  Removing carbon dioxide · CPC title