US4374105A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of fuel gases
Assignee: Gas Technology Institute
•
Filing: 1979-12-11
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Granted: 1983-02-15
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Expires: 1999-12-11
Abstract
Abstract A process for substantial removal of nitrogen and sulfur compounds from gas streams, particularly fuel gas mixtures produced from sulfur and nitrogen containing coal or other carbonaceous fuels, by contacting the gas stream with solid zinc oxide at elevated temperatures in a reaction zone. The process provides a continuous method of removal of ammonia and hydrogen sulfide by contacting the gas stream with zinc oxide solids and regenerating the sulfided zinc in a fluidized bed regeneration zone by contact with oxygen containing gas at elevated temperatures. The process provides simultaneous removal of sulfur and nitrogen components of a fuel gas stream without requiring a decrease in the temperature of the fuel gas stream.
Inventors
- 👤 Gerald L. Anderson
- 👤 Harley A. Borders
- 👤 Maria R. Aquino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:37
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
58 words
A process for substantial removal of ammonia from reducing gas streams comprising: contacting said reducing gas stream with solid zinc oxide (ZnO) in a reaction zone at temperatures of about 400° to about 1400° F.; decomposing said ammonia in said reducing gas in contact with said solid zinc oxide producing an equilibrium mixture of ammonia, hydrogen and nitrogen.
Claim 2
Dependent Claim
58 words
A process for substantial removal of ammonia from reducing gas streams comprising: contacting said reducing gas stream with solid zinc oxide (ZnO) in a reaction zone at temperatures of about 400° to about 1400° F.; decomposing said ammonia in said reducing gas in contact with said solid zinc oxide producing an equilibrium mixture of ammonia, hydrogen and nitrogen.
Claim 3
Dependent Claim
32 words
The process of claim 1 wherein the temperature is maintained at about 800° to about 1300° F. in a fluidized bed maintained in fluidized state by the flow of said gas stream.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein the pressure is maintained at atmospheric to about 2000 psig.
Claim 5
Dependent Claim
16 words
The process of claim 3 wherein the pressure is maintained at atmospheric to about 300 psig.
Claim 6
Dependent Claim
40 words
The process of claim 1 wherein said gas stream is a fuel gas mixture comprising ammonia and hydrogen sulfide produced from sulfur and nitrogen containing carbonaceous fuel and said reaction zone is maintained at about 800° to about 1400° F.
Claim 7
Dependent Claim
24 words
The process of claim 5 wherein said hydrogen sulfide reacts with said zinc oxide (ZnO) in said reaction zone forming sulfided zinc and water.
Claim 8
Dependent Claim
47 words
The process of claim 6 wherein sulfided zinc is regenerated to zinc oxide in a regeneration zone for recycle to said reaction zone by contacting said sulfided zinc with an oxygen containing gas stream in said regeneration zone at temperatures of about 1600° to about 2000° F.
Claim 9
Dependent Claim
21 words
The process of claim 7 wherein the temperature in said regeneration zone is maintained at about 1800° to about 2000° F.
Claim 10
Dependent Claim
138 words
A process for the continuous and simultaneous substantial removal of hydrogen sulfide and ammonia from reducing gas streams comprising: contacting said reducing gas stream with solid zinc oxide (ZnO) in a reaction zone at temperatures of about 400° to about 1400° F.; decomposing said ammonia in said reducing gas producing an equilibrium mixture of ammonia, hydrogen and nitrogen; and reacting said hydrogen sulfide with said solid zinc oxide producing sulfided zinc and water; continuously removing a portion of said sulfided zinc solids from said reaction zone; regenerating zinc oxide (ZnO) by treating said sulfided zinc with oxygen containing gas at elevated temperatures in a regeneration zone; and recycling the regenerated zinc oxide (ZnO) to said reaction zone. There should be no charge for the above amendment since it does not alter the number of claims in this application.
Claim 11
Dependent Claim
30 words
The process of claim 9 wherein said solid zinc oxide (ZnO) and said sulfided zinc is maintained as a fluidized bed in said reaction zone and said regeneration zone, respectively.
Claim 12
Dependent Claim
21 words
The process of claim 10 wherein the temperature in said reaction zone is maintained at about 800° to about 1300° F.
Claim 13
Dependent Claim
21 words
The process of claim 10 wherein the temperature in said regeneration zone is maintained at about 1600° to about 2000° F.
Claim 14
Dependent Claim
21 words
The process of claim 13 wherein the temperature in said regeneration zone is maintained at about 1800° to about 2000° F.
Claim 15
Dependent Claim
12 words
The process of claim 9 wherein said oxygen containing gas is air.
Claim 16
Dependent Claim
43 words
The process of claim 9 wherein said reaction zone is maintained at a temperature of about 800° to about 1300° F., said regeneration zone is maintained at a temperature of about 1800° to about 2000° F. and said oxygen containing gas is air.
Claim 17
Dependent Claim
25 words
The process of claim 9 wherein said solid zinc oxide (ZnO) is carried on a material selected from the group consisting of alumina and chromia-alumina.
Claim 18
Dependent Claim
40 words
The process of claim 9 wherein said gas stream is a fuel gas mixture comprising ammonia and hydrogen sulfide produced from sulfur and nitrogen containing carbonaceous fuel and said reaction zone is maintained at about 800° to about 1400° F.
Claim 19
Dependent Claim
47 words
The process of claim 9 wherein sulfided zinc is regenerated to zinc oxide in a regeneration zone for recycle to said reaction zone by contacting said sulfided zinc with an oxygen containing gas stream in said regeneration zone at temperatures of about 1600° to about 2000° F.
Claim 20
Dependent Claim
21 words
The process of claim 9 wherein the temperature in said regeneration zone is maintained at about 1800° to about 2000° F.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-14 | 1986-08-16 | 1987-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-14 | 1990-08-16 | 1991-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-14 | 1994-08-16 | 1995-02-15 | $7700.00 | Window Closed / Lapsed |