US3880618A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Simultaneously removing sulfur and nitrogen oxides from gases
Assignee: Individual
•
Filing: 1973-03-02
•
Granted: 1975-04-29
•
Expires: 1993-03-02
Abstract
Abstract Hot flue gas is cooled to 75-150*C and passed over alkalized alumina or alkali metal carbonate or oxide to simultaneously remove sulfur oxides and nitrogen oxides. Absorbent is regenerated by first heating to 300*-400*C to drive off NO, and then heating to 600*-700*C to drive off absorbed sulfur compounds.
Inventors
- 👤 Donald H Mccrea
- 👤 John G Myers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:34
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/60; B01D53/02; B01D53/04; B01D53/54; B01D53/56; B01D2253/00; B01D2253/10; B01D2253/104; B01D2257/00; B01D2257/30; B01D2257/302; B01D2257/40; B01D2257/404; B01D2259/00; B01D2259/40; B01D2259/401; Y; Y02; Y02A; Y02A50/00; Y02A50/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
95 words
A PROCESS FOR REMOVING NITROGEN OXIDES, SELECTED FROM THE GROUP CONSISTING OF NO AND NO2, FROM A GAS WHICH CONTAINS AT LEAST 200 PPM OF SULFUR DIOXIDE WHICH COMPRISES CONTACTING SAID GAS AT A TEMPERATURE OF ABOUT 75*-150*C. WITH A SOLID ABSORBENT SELECTED FROM THE GROUP CONSISTING OF ALKALIZED ALUMINA, SODIUM, AND POTASSIUM CARBONATE OR OXIDE, RECOVERING NITROGEN OXIDES FROM SAID ABSORBENT BY HEATING IT TO A TEMPERATURE OF 300*-400*C AND THEREAFTER REGENERATING FROM ABSORBENT TO A TEMPERATURE OF 600*-700*C IN THE PRESENCE OF A REDUCING GAS WHEREBY SULFUR COMPOUNDS ARE REMOVED FROM THE ABSORBENT.
Claim 2
Dependent Claim
95 words
A PROCESS FOR REMOVING NITROGEN OXIDES, SELECTED FROM THE GROUP CONSISTING OF NO AND NO2, FROM A GAS WHICH CONTAINS AT LEAST 200 PPM OF SULFUR DIOXIDE WHICH COMPRISES CONTACTING SAID GAS AT A TEMPERATURE OF ABOUT 75*-150*C. WITH A SOLID ABSORBENT SELECTED FROM THE GROUP CONSISTING OF ALKALIZED ALUMINA, SODIUM, AND POTASSIUM CARBONATE OR OXIDE, RECOVERING NITROGEN OXIDES FROM SAID ABSORBENT BY HEATING IT TO A TEMPERATURE OF 300*-400*C AND THEREAFTER REGENERATING FROM ABSORBENT TO A TEMPERATURE OF 600*-700*C IN THE PRESENCE OF A REDUCING GAS WHEREBY SULFUR COMPOUNDS ARE REMOVED FROM THE ABSORBENT.
Claim 3
Dependent Claim
14 words
The process of claim 1 wherein said contacting temperature is about 100* - 130*C.
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein said gas is produced by burning coal or oil.
Claim 5
Dependent Claim
14 words
The process of claim 3 wherein said contacting temperature is about 100* - 130*C.
References Cited (Backward Citations)
US2992884A
Cited
US3502427A
Cited
US3389961A
Cited
US3498743A
Cited
US3524720A
Cited
US3660040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |