Gas absorber method and apparatus

• US 5,064,450 A
• Filed: 01/02/1991
• Issued: 11/12/1991
• Est. Priority Date: 01/02/1991
• Status: Expired due to Fees

• Current Assignee: UOP Des Plaines IL
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: James, Robert B. Jr., Lankton, Steven P.
• Primary Examiner(s): Nozick, Bernard
• Application Number:
  US07/636,784
• Time in Patent Office: 314 Days
• Field of Search: 55/70, 55/71, 55/73, 55/90, 55/233, 55/220, 261/94-98
• US Class Current: 95/211
• CPC Class Codes: B01D 47/06 Spray cleaning
• CPC Class Codes: B01D 53/18 Absorbing units; Liquid distributors therefor B01D3/16, B01D3/26, B01D3/30 take precedence; packing elements B01J19/30, B01J19/32

Abstract

A gas absorber for removing at least one gaseous component from a flowing gas stream by contacting the gas stream with a lean liquid stream to absorb at least a portion of the gaseous component to produce a rich liquid stream comprising the gaseous component and a flowing gas stream having a reduced concentration of the gaseous component which absorber comprises: (a) a double wall forming an annulus having a means for restricting fluid flow into the bottom of the gas absorber from the bottom of the annulus and a means for passing fluid out of an upper section of the annulus into the gas absorber; (b) an inlet for the lean liquid stream having a locus in the upper end of the gas absorber; (c) an inlet for the flowing gas stream; (d) an outlet for the rich liquid stream having a locus in the lower end of the gas absorber; (e) an outlet for the flowing gas stream having a reduced concentration of the gaseous component; and (f) at least one inlet communicating with the lower end of the annulus which inlet is used to introduce a lean liquid stream at least a portion of which flows upwardly through the annulus and overflows from the top of the annulus and thereby protecting at least a portion of the outer wall from contact with the flowing gas stream.

Claims

1. A gas absorber for removing at least one gaseous component from a flowing gas stream by contacting said gas stream with a lean liquid stream to absorb at least a portion of said gaseous component to produce a rich liquid stream comprising said gaseous component and a flowing gas stream having a reduced concentration of said gaseous component which absorber comprises:

(a) a double wall forming an annulus having a means for restricting fluid flow into the bottom of said gas absorber from the bottom of said annulus and a means for passing fluid out of an upper section of said annulus into said gas absorber;

(b) an inlet for said lean liquid stream having a locus in the upper end of said gas absorber;

(c) an inlet for said flowing gas stream;

(d) an outlet for said rich liquid stream having a locus in the lower end of said gas absorber;

(e) an outlet for said flowing gas stream having a reduced concentration of said gaseous component; and

(f) at least one inlet communicating with the lower end of said annulus which inlet is used to introduce a lean liquid stream at least a portion of which flows upwardly through said annulus and overflows from said top of said annulus and thereby protecting at least a portion of the outer wall from contact with said flowing gas stream.

2. The gas absorber of claim 1 wherein said gas absorber contains a gas/liquid contacting zone comprising packing.

3. The gas absorber of claim 2 wherein said packing comprises metal mesh.

4. The gas absorber of claim 2 wherein said packing is selected from the group consisting of divided carbon particles, Raschig rings, Lessing rings, Berl saddles and grid packing.

5. A process for removing at least one gaseous component from a flowing gas stream by contacting said gas stream with a lean liquid stream in a gas absorber to absorb at least a portion of said gaseous component to produce a rich liquid stream comprising said gaseous component and a flowing gas stream having a reduced concentration of said gaseous component wherein said process comprises:

(a) passing a first lean liquid stream through at least one inlet communicating with the lower end of a double wall forming an annulus having a means for restricting fluid flow into the bottom of said gas absorber from the bottom of said annulus and a means for fluid flow out of the top of said annulus into said gas absorber wherein at least a portion of said first lean liquid stream flows upwardly through said annulus and overflows from said top of said annulus thereby protecting at least a portion of the outer wall of said gas absorber from contact with said flowing gas stream;

(b) passing a second lean liquid stream through an inlet having a locus in the upper end of said gas absorber;

(c) passing said flowing gas stream through an inlet into said gas absorber;

(d) contacting said second lean liquid stream with said flowing gas stream to produce said rich liquid stream comprising at least a portion of said gaseous component and said flowing gas stream having a reduced concentration of said gaseous component;

(e) recovering said rich liquid stream comprising at least a portion of said gaseous component from an outlet having a locus in the lower end of said gas absorber; and

(f) recovering said flowing gas stream having a reduced concentration of said gaseous component from an outlet having a locus in the upper end of said gas absorber.

6. The process of claim 5 wherein said flowing gas stream contains a gaseous component selected from the group consisting of hydrogen chloride, hydrogen fluoride, hydrogen, sulfur dioxide, hydrogen sulfide and ammonia.

7. The process of claim 5 wherein said gas absorber is operated at conditions which include a temperature from about 50°

F. (10°

C.) to about 250°

F. (121°

C. ), a pressure from about atmospheric to about 1000 psig (6896 kPa gauge), a gas hourly space velocity from about 800 hr^-1 and a gas/liquid mass ratio from about 0.01 to about 4.

8. The process of claim 5 wherein said first and said second lean liquid streams are aqueous.

9. The process of claim 5 wherein said gas absorber contains a gas/liquid contacting zone comprising packing.

10. The process of claim 9 wherein said packing comprises metal mesh.

11. The process of claim 9 wherein said packing is selected from the group consisting of finely divided carbon particles, Raschig rings, Lessing rings, Berl saddles and grid packing.