CO2 separation device in gas and its membrane separation method and method for controlling membrane separation of CO2 separation device in gas

Patent metadata

Field	Value
Publication number	US-10913027-B2
Application number	US-201515525365-A
Country	US
Kind code	B2
Filing date	Oct 21, 2015
Priority date	Nov 12, 2014
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A source gas introduction line for introducing source gas containing CO 2 , a first membrane separator for membrane-separating CO 2 from source gas, a first permeable gas discharge line for discharging first permeable gas permeated by membrane separation of the first membrane separator, a first non-permeable gas discharge line for discharging first non-permeable gas not permeated by membrane separation of the first membrane separator, a second membrane separator provided at a downstream side of the first membrane separator and for further membrane-separating CO 2 from the first non-permeable gas, a second permeable gas discharge line for discharging second permeable gas permeated by membrane separation of the second membrane separator, a second permeable gas return line branched from a part of the second permeable gas discharge line and for returning the second permeable gas to a source gas side, and a CO 2 concentration meter are included.

First claim

The invention claimed is:

1. A CO 2 separation device in gas, comprising:
a source gas introduction line configured to introduce source gas containing CO 2 ,
a first membrane separator connected to an end of the source gas introduction line and configured to membrane-separate CO 2 from the source gas;
a first permeable gas discharge line configured to discharge first permeable gas permeated by membrane separation of the first membrane separator to be collected as collected CO 2 ;
a first non-permeable gas discharge line configured to discharge first non-permeable gas not permeated by membrane separation of the first membrane separator;
a second membrane separator provided at a downstream side of the first membrane separator and configured to membrane-separate CO 2 from first non-permeable gas;
a second permeable gas discharge line configured to discharge second permeable gas permeated by membrane separation of the second membrane separator to be collected as collected CO 2 ;
a first permeable gas branch line branched from a part of the first permeable gas discharge line and configured to return the first permeable gas to the source gas;
a return line of second permeable gas branched from a part of the second permeable gas discharge line and configured to return the second permeable gas to a source gas side or a first non-permeable gas side; and
a CO 2 concentration meter provided in the first permeable gas discharge line and configured to measure CO 2 concentration in the first permeable gas; wherein
the second permeable gas and a part of the first permeable gas is recycled to the source gas side in the case where the CO 2 concentration in the first permeable gas is 90 mol % or less.

2. The CO 2 separation device in gas according to claim 1 , further comprising a CO 2 concentration meter for measuring CO 2 concentration in the source gas or the first permeable gas or the second permeable gas.

3. The CO 2 separation device in gas according to claim 1 , further comprising:
a CO 2 concentration meter for measuring CO 2 concentration in the source gas; and
a third membrane separator for pre-processing provided at an upstream side of the first membrane separator and configured to separate CO 2 in the source gas in accordance with CO 2 concentration in the source gas to obtain source gas having CO 2 gas concentration of the predetermined concentration.

4. The CO 2 separation device in gas according to claim 1 , in which a compressor provided in the source gas introduction line and configured to compress the introduced source gas is provided at an upstream side of the first membrane separator.

5. The CO 2 separation device in gas according to claim 1 , further comprising:
CO 2 separation equipment for further separating CO 2 in the second non-permeable gas discharged from the part of the second non-permeable gas discharge line; and
a return line of CO 2 gas configured to return the CO 2 gas separated by the CO 2 separation equipment to the source gas or the first non-permeable gas.

6. The CO 2 separation device in gas according to claim 1 , further comprising a compressor in the second permeable gas discharge line at a location after the return line of second permeable gas for compressing the second permeable gas to be collected as CO 2 .

7. A CO 2 separation device in gas, comprising:
a source gas introduction line configured to introduce source gas containing CO 2 ,
a first membrane separator connected to an end of the source gas introduction line and configured to membrane-separate CO 2 from the source gas;
a first permeable gas discharge line configured to discharge first permeable gas permeated by membrane separation of the first membrane separator to be collected as collected CO 2 ;
a first non-permeable gas discharge line configured to discharge first non-permeable gas not permeated by membrane separation of the first membrane separator;
a second membrane separator provided at a downstream side of the first membrane separator and configured to membrane-separate CO 2 from first non-permeable gas;
a second permeable gas discharge line configured to discharge second permeable gas permeated by membrane separation of the second membrane separator to be collected as collected CO 2 ;
a return line of second permeable gas branched from a part of the second permeable gas discharge line and configured to return the second permeable gas to a source gas side or a first non-permeable gas side; and
a CO 2 concentration meter provided in the source gas introduction line and configured to measure CO 2 concentration in the source gas; wherein
the second permeable gas is recycled to the source gas side in the case where the CO 2 concentration in the source gas is 20 mol % or less.

8. The CO 2 separation device in gas according to claim 7 , further comprising a first permeable gas branch line branched from a part of the first permeable gas discharge line and configured to return the first permeable gas to the source gas.

9. The CO 2 separation device in gas according to claim 7 , further comprising a CO 2 concentration meter for measuring CO 2 concentration in the source gas or the first permeable gas or the second permeable gas.

10. The CO 2 separation device in gas according to claim 7 , further comprising:
a CO 2 concentration meter for measuring CO 2 concentration in the source gas; and
a third membrane separator for pre-processing provided at an upstream side of the first membrane separator and configured to separate CO 2 in the source gas in accordance with CO 2 concentration in the source gas to obtain source gas having CO 2 gas concentration of the predetermined concentration.

11. The CO 2 separation device in gas according to claim 7 , in which a compressor provided in the source gas introduction line and configured to compress the introduced source gas is provided at an upstream side of the first membrane separator.

12. The CO 2 separation device in gas according to claim 7 , further comprising:
CO 2 separation equipment for further separating CO 2 in the second non-permeable gas discharged from the part of the second non-permeable gas discharge line; and
a return line of CO 2 gas configured to return the CO 2 gas separated by the CO 2 separation equipment to the source gas or the first non-permeable gas.

13. A method of membrane separation in a CO 2 separation device in gas comprising:
serially providing membrane separators including separation membrane for selectively separating CO 2 from source gas containing CO 2 in two stages;
discharging first permeable gas permeated by membrane separation of the first membrane separator to be collected as collected CO 2 and second permeable gas permeated by membrane separation of the second membrane separator to be collected as collected CO 2 ,
obtaining CO 2 concentration in the source gas or the first permeable gas after membrane separation by the first membrane separator when first non-permeable gas not permeated by membrane separation of the first membrane separator in the first stage is membrane-separated by the second membrane separator in the second stage;
recycling the second permeable gas after membrane separation by the second membrane separator to a source gas side in the case where the obtained CO 2 concentration in the first permeable gas is 90 mol % or less, or the obtained CO 2 concentration in the source gas is 20 mol % or less; and
returning the first permeable gas after membrane separation by the first membrane separator to the source gas.

14. A method of membrane separation in a CO 2 separation de

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Hirata Takuya
• Horizoe Kouji

Classifications

• C10L2290/10

  Recycling of a stream within the process or apparatus to reuse elsewhere therein · CPC title

• B01D53/226 Primary

  in serial connexion · CPC title

• B01D53/1443

  Pretreatment by diffusion · CPC title

• B01D2257/504

  Carbon dioxide · CPC title

• C10L2290/548

  Membrane- or permeation-treatment for separating fractions, components or impurities during preparation or upgrading of a fuel · CPC title