US4342731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing hydrogen sulfide from coke oven gas
Assignee: Dr C Otto and Co GmbH
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Filing: 1981-04-13
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Granted: 1982-08-03
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Expires: 2001-04-13
Abstract
Abstract An improved sulfur-ammonia process for removing hydrogen sulfide from coke oven gases. In the improved process, a concentrator formerly used for standby operation is used at all normal times as an ammonia scrubber to improve the efficiency of gas separation during normal operation and is used as a concentrator for its intended standby functions during the alternative operations. In its normal function, the concentrator/scrubber functions as a scrubber to strip ammonia gas from recirculating liquid streams and to permit introduction of an ammonia-rich gas into a hydrogen sulfide scrubber to increase the separation efficiency of that unit. In the standby operation, the same concentrator/scrubber serves as a concentrator to concentrate hydrogen sulfide in a "strong liquor" stream for separate recovery as a "strong liquor."
Inventors
- 👤 Horst Ritter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:24
CPC Classifications
C; C10; C10K; C10K1/00; C10K1/08; C10K1/10; C10K1/12; B; B01; B01D; B01D53/00; B01D53/14; B01D53/1456; B01D53/1468; C01; C01B; C01B17/00; C01B17/16; C01B17/167; C01C; C01C1/00; C01C1/02; C01C1/12; C10K1/121
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
452 words
In the sulfur-ammonia process for recovering hydrogen sulfide from coke oven gas containing hydrogen sulfide and ammonia, comprising (a) a hydrogen sulfide stripping zone; (b) an ammonia stripping zone; (c) a deacidifying zone; (d) an ammonia distillation zone; (e) a concentrating/scrubbing zone; feeding said coke oven gas and ammoniacal wash water to said hydrogen sulfide stripping zone and removing a first washed gas stream having a lower hydrogen sulfide content than said coke oven gas and recovering a first effluent liquid stream including ammoniacal water and hydrogen sulfide; feeding said first washed gas stream to said ammonia stripping zone along with wash water to produce a second washed gas stream having a lower ammonia content than said first washed gas stream and producing a second effluent liquid stream; recovering said second washed gas stream as a first product gas stream of washed coke oven gas and returning said second effluent liquid stream to said hydrogen sulfide stripping zone as at least a portion of the required ammoniacal wash water; feeding said first effluent liquid stream to said deacidifying zone along with ammonia-rich gas to produce a second product gas stream containing hydrogen sulfide and to produce a third effluent liquid stream of wash water containing ammonia; stripping at least a portion of said third effluent liquid stream to produce a fourth effluent liquid stream and to produce the said ammonia-rich gas; delivering the said ammonia-rich gas to said deacidifying zone; the improvement in said process comprising operating said concentrating/scrubbing zone alternatively Firstly: as a scrubbing zone when said second product gas stream is continuously withdrawn as a product; introducing a portion of said first product gas stream into said concentrating/scrubber zone and washing therein with a portion of the said third effluent liquid stream to produce a third washed gas stream having a lower hydrogen sulfide content than the said second product gas stream and producing a fifth effluent liquid stream, recycling at least a portion of said fifth effluent liquid stream to said concentrating/scrubbing zone and delivering at least a portion thereof to said hydrogen sulfide stripping zone as a portion of the said ammoniacal wash water; and introducing said third washed gas stream into said hydrogen sulfide stripping zone along with the said coke oven gas; and Secondly: as a concentrating zone when said second product gas stream is delivered entirely to said concentrating/scrubbing zone, delivering a portion of said third effluent liquid stream to said concentrating/scrubbing zone to produce a third washed gas stream, returning said third washed gas stream to said hydrogen sulfide stripping zone along with coke oven gas; and withdrawing a portion of the said fifth effluent liquid stream as a strong liquor containing hydrogen sulfide.
Claim 2
Dependent Claim
452 words
In the sulfur-ammonia process for recovering hydrogen sulfide from coke oven gas containing hydrogen sulfide and ammonia, comprising (a) a hydrogen sulfide stripping zone; (b) an ammonia stripping zone; (c) a deacidifying zone; (d) an ammonia distillation zone; (e) a concentrating/scrubbing zone; feeding said coke oven gas and ammoniacal wash water to said hydrogen sulfide stripping zone and removing a first washed gas stream having a lower hydrogen sulfide content than said coke oven gas and recovering a first effluent liquid stream including ammoniacal water and hydrogen sulfide; feeding said first washed gas stream to said ammonia stripping zone along with wash water to produce a second washed gas stream having a lower ammonia content than said first washed gas stream and producing a second effluent liquid stream; recovering said second washed gas stream as a first product gas stream of washed coke oven gas and returning said second effluent liquid stream to said hydrogen sulfide stripping zone as at least a portion of the required ammoniacal wash water; feeding said first effluent liquid stream to said deacidifying zone along with ammonia-rich gas to produce a second product gas stream containing hydrogen sulfide and to produce a third effluent liquid stream of wash water containing ammonia; stripping at least a portion of said third effluent liquid stream to produce a fourth effluent liquid stream and to produce the said ammonia-rich gas; delivering the said ammonia-rich gas to said deacidifying zone; the improvement in said process comprising operating said concentrating/scrubbing zone alternatively Firstly: as a scrubbing zone when said second product gas stream is continuously withdrawn as a product; introducing a portion of said first product gas stream into said concentrating/scrubber zone and washing therein with a portion of the said third effluent liquid stream to produce a third washed gas stream having a lower hydrogen sulfide content than the said second product gas stream and producing a fifth effluent liquid stream, recycling at least a portion of said fifth effluent liquid stream to said concentrating/scrubbing zone and delivering at least a portion thereof to said hydrogen sulfide stripping zone as a portion of the said ammoniacal wash water; and introducing said third washed gas stream into said hydrogen sulfide stripping zone along with the said coke oven gas; and Secondly: as a concentrating zone when said second product gas stream is delivered entirely to said concentrating/scrubbing zone, delivering a portion of said third effluent liquid stream to said concentrating/scrubbing zone to produce a third washed gas stream, returning said third washed gas stream to said hydrogen sulfide stripping zone along with coke oven gas; and withdrawing a portion of the said fifth effluent liquid stream as a strong liquor containing hydrogen sulfide.
Claim 3
Dependent Claim
25 words
The improvement of claim 1 wherein the said concentrating/scrubbing zone, when operating as a scrubbing zone, receives ammonia-rich gas from the said ammonia distillation zone.
Claim 4
Dependent Claim
33 words
A method according to claim 1, characterized in withdrawing an ammonia-containing gas by suction from said hydrogen sulfide scrubbing zone and delivering said ammonia-containing gas by pressure into the said ammonia stripping zone.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-08-02 | 1986-02-01 | 1986-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-02 | 1990-02-01 | 1990-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-02 | 1994-02-01 | 1994-08-03 | $7700.00 | Window Closed / Lapsed |