Apparatus and method for absorbing a component from a gas mixture using rotating packed bed unit

Patent metadata

Field	Value
Publication number	US-2018318753-A1
Application number	US-201816036959-A
Country	US
Kind code	A1
Filing date	Jul 17, 2018
Priority date	Dec 8, 2015
Publication date	Nov 8, 2018
Grant date	—

Abstract

Provided herein is a method for absorbing CO 2 from a gas mixture. The method includes using an apparatus comprised of a first RPB unit and a second RPB unit. The first RPB unit and the second RPB unit are arranged to absorb CO 2 in a first gas stream and a second gas stream, respectively. A liquid CO 2 -absorbent is supplied sequentially passing through the first RPB unit and the second RPB unit to absorb CO 2 in the first gas stream and the second gas stream. The liquid CO 2 -absorbent is regenerated to produce a regenerated CO 2 -absorbent. The regenerated CO 2 -absorbent is transported to the first RPB unit.

First claim

What is claimed is:

1 . A method for absorbing CO 2 from a gas mixture, comprising:
providing or receiving a first rotating packed bed (RPB) unit comprising a first RPB, a first gas inlet, a first gas outlet, a first CO 2 -absorbent inlet, and a first CO 2 -absorbent outlet, and a second RPB unit comprising a second RPB, a second gas inlet, a second gas outlet, a second CO 2 -absorbent inlet and a second CO 2 -absorbent outlet, wherein the first CO 2 -absorbent outlet of the first RPB unit is connected to the second CO 2 -absorbent inlet of the second RPB unit; transporting a first gas stream containing CO 2 from the first gas inlet through the first RPB to the first gas outlet, wherein the first gas stream has a first CO 2 volumetric percentage ranged from 1 vol % to 30 vol %; transporting a second gas stream containing CO 2 from the second gas inlet through the second RPB to the second gas outlet, wherein the second gas stream has a second CO 2 volumetric percentage ranged from 1 vol % to 30 vol %; transporting a CO 2 -absorbent from the first CO 2 -absorbent inlet through the first RPB, the first CO 2 -absorbent outlet, the second CO 2 -absorbent inlet and the second RPB to the second CO 2 -absorbent outlet in sequence such that the CO 2 -absorbent absorbs the CO 2 in the first and the second gas streams, thereby generating a CO 2 -absorbed absorbent; regenerating the CO 2 -absorbed absorbent discharged from the second CO 2 -absorbent outlet, wherein the regenerating the CO 2 -absorbed absorbent comprises converting a portion of the absorbed CO 2 in the CO 2 -absorbed absorbent into gaseous CO 2 to produce a regenerated CO 2 -absorbent; and transporting the regenerated CO 2 -absorbent to the first CO 2 -absorbent inlet.

2 . The method according to claim 1 , further comprising operating the first RPB unit and the second RPB unit to respectively have a first CO 2 capture percentage and a second CO 2 capture percentage with respect to the first gas stream and the second gas stream, and both the first CO 2 capture percentage and the second CO 2 capture percentage are greater than 60%.

3 . The method according to claim 1 , wherein the first gas stream has a first CO 2 molar flow rate, and the second gas stream has a second CO 2 molar flow rate that is substantially equal to or less than the first CO 2 molar flow rate of the first gas stream.

4 . The method according to claim 3 , wherein the second CO 2 molar flow rate of the second gas stream is 50-100% of the first CO 2 molar flow rate of the first gas stream.

5 . The method according to claim 1 , wherein the first gas stream has a first CO 2 concentration, and the second gas stream has a second CO 2 concentration that is substantially equal to the first CO 2 concentration of the first gas stream.

6 . The method according to claim 5 , wherein the first gas stream and the second gas stream are produced by a same exhaust source.

7 . The method according to claim 1 , wherein the regenerating the CO 2 -absorbed absorbent discharged from the second CO 2 -absorbent outlet comprises:
transporting the CO 2 -absorbent into a third RPB unit; and introducing a gaseous regenerant into the third RPB unit to convert the absorbed CO 2 in the CO 2 -absorbed absorbent into gaseous CO 2 to produce the regenerated CO 2 -absorbent.

8 . The method according to claim 1 , wherein the regenerating the CO 2 -absorbed absorbent discharged from the second CO 2 -absorbent outlet comprises using a stripping column to convert the absorbed CO 2 in the CO 2 -absorbed absorbent into gaseous CO 2 to produce the regenerated CO 2 -absorbent.

9 . The method according to claim 1 , wherein the first gas stream has a first gas volumetric flow rate, the CO 2 -absorbent has a liquid volumetric flow rate throughout the first and second RPB units, and the ratio of the first gas volumetric flow rate to the liquid volumetric flow rate ranges from 30 to 300.

10 . The method according to claim 1 , wherein the second gas stream has a second gas volumetric flow rate, the CO 2 -absorbent has a liquid volumetric flow rate throughout the first and second RPB units, and the ratio of the second gas volumetric flow rate to the liquid volumetric flow rate ranges from 30 to 300.

11 . The method according to claim 1 , wherein the CO 2 -absorbent absorbs CO 2 only in the first RPB unit and the second RPB unit.

Assignees

• Univ Nat Tsing Hua
• Chang Chun Plastics Co Ltd
• Chang Chun Petrochemical Co Ltd

Inventors

• Yu Cheng-Hsiu
• Tan Chung-Sung

Classifications

• B01D2257/504

  Carbon dioxide · CPC title

• B01D2252/20484

  with one hydroxyl group · CPC title

• B01D2252/20489

  with two or more hydroxyl groups · CPC title

• B01D2256/24

  Hydrocarbons · CPC title

• B01D2258/025

  from metallurgy plants · CPC title