US3852410A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfur dioxide and particulate contaminant removal from industrial stack gases
Assignee: American Air Filter Co Inc
•
Filing: 1972-12-07
•
Granted: 1974-12-03
•
Expires: 1992-12-07
Abstract
Abstract Sulfur dioxide and particulate contaminants are removed from industrial waste gases by a method which provides for a highly active sulfur dioxide reactant to be utilized and regenerated. The method further includes discharging stable, insoluble sulfur containing compounds thus eliminating possible reintroduction of sulfur into the environment and regeneration of the sulfur dioxide reactant by using carbon dioxide contained in the stack gas stream.
Inventors
- 👤 R Rivers
- 👤 M Pasha
- 👤 J Goldsmith
- 👤 R Pring
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:52
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/508; B01D53/501
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
202 words
A METHOD FOR REMOVAL OF SULFUR DIOXIDE AND PARTICULATE CONTAMINANTS FROM INDUSTRIAL WASTE GASES PRIOR TO THEIR DISCHARGE INTO THE ATMOSPHERE, SAID METHOD UTILIZING SULFUR DIOXIDE REACTANTS OF SUITABLE ACTIVITY WHICH ARE SUBSEQUENTLY REGENERATED, SAID METHOD FURTHER RESULTING IN STABLE INSOLUBLE SULFUR CONTAINING COMPOUNDS TO BE DISCARDED SAID METHOD COMPRISING: DEPOSITING SOLUBLE ALKALINE SODIUM COMPOUNDS ONTO FILTERING SURFACES OF A FABRIC TYPE DUST COLLECTOR SAID FINELY DIVIDED ALKALINE SODIUM COMPOUNDS BEING SELECTED FROM THE GROUP OF SODIUM CARBONATE SODIUM BICARBONATE, HYDRATED SODIUM CARBONATES, SODIUM SESQUICARBONATE, THE NATURAL OCCURRING ORES, NAHCOLITE AND TRONA, CONTAINING SAID ALKALINE SODIUM COMPOUNDS, AND COMBINATIONS THEREOF, PASSING WASTE GASES COMPRISING SULFUR DIOXIDE, CARBON DIOXIDE AND PARTICULATE CONTAMINANTS THROUGH SAID DUST COLLECTOR WHEREUPON SAID PARTICULATE CONTAMINANTS ARE RESTRAINED BY SAID DUST COLLECTOR AND WHEREUPON A PORTION OF SAID SULFUR DIOXIDE REACTS WITH SAID SOLUBLE AKALINE SODIUM COMPOUNDS TO FORM SOLUBLE REACTION PRODUCTS; PERIODICALLY REMOVING SAID SOLUBLE REACTION PRODUCTS, UNREACTED SOLUBLE ALKALINE SODIUM COMPOUNDS AND PARTICULATE CONTAMINANTS FROM SAID DUST COLLECTOR; LEACHING SAID SOLUBLE REACTION PRODUCT AND THE UNREACTED PORTION OF SAID SOLUBLE ALKALINE SODIUM COMPOUNDS FROM SAID PARTICULATE CONTAMINANTS INTO A LEACH LIQUOR TREATING SAID LEACH LIQUOR WITH CALCIUM HYDROXIDE TO PRECIPITATE STALE CALCIUM SATS, HAVING ANIONS INCLUDING ELE-
Claim 2
Independent Claim
202 words
A METHOD FOR REMOVAL OF SULFUR DIOXIDE AND PARTICULATE CONTAMINANTS FROM INDUSTRIAL WASTE GASES PRIOR TO THEIR DISCHARGE INTO THE ATMOSPHERE, SAID METHOD UTILIZING SULFUR DIOXIDE REACTANTS OF SUITABLE ACTIVITY WHICH ARE SUBSEQUENTLY REGENERATED, SAID METHOD FURTHER RESULTING IN STABLE INSOLUBLE SULFUR CONTAINING COMPOUNDS TO BE DISCARDED SAID METHOD COMPRISING: DEPOSITING SOLUBLE ALKALINE SODIUM COMPOUNDS ONTO FILTERING SURFACES OF A FABRIC TYPE DUST COLLECTOR SAID FINELY DIVIDED ALKALINE SODIUM COMPOUNDS BEING SELECTED FROM THE GROUP OF SODIUM CARBONATE SODIUM BICARBONATE, HYDRATED SODIUM CARBONATES, SODIUM SESQUICARBONATE, THE NATURAL OCCURRING ORES, NAHCOLITE AND TRONA, CONTAINING SAID ALKALINE SODIUM COMPOUNDS, AND COMBINATIONS THEREOF, PASSING WASTE GASES COMPRISING SULFUR DIOXIDE, CARBON DIOXIDE AND PARTICULATE CONTAMINANTS THROUGH SAID DUST COLLECTOR WHEREUPON SAID PARTICULATE CONTAMINANTS ARE RESTRAINED BY SAID DUST COLLECTOR AND WHEREUPON A PORTION OF SAID SULFUR DIOXIDE REACTS WITH SAID SOLUBLE AKALINE SODIUM COMPOUNDS TO FORM SOLUBLE REACTION PRODUCTS; PERIODICALLY REMOVING SAID SOLUBLE REACTION PRODUCTS, UNREACTED SOLUBLE ALKALINE SODIUM COMPOUNDS AND PARTICULATE CONTAMINANTS FROM SAID DUST COLLECTOR; LEACHING SAID SOLUBLE REACTION PRODUCT AND THE UNREACTED PORTION OF SAID SOLUBLE ALKALINE SODIUM COMPOUNDS FROM SAID PARTICULATE CONTAMINANTS INTO A LEACH LIQUOR TREATING SAID LEACH LIQUOR WITH CALCIUM HYDROXIDE TO PRECIPITATE STALE CALCIUM SATS, HAVING ANIONS INCLUDING ELE-
Claim 3
Dependent Claim
33 words
The method of claim 1 wherein said reformed soluble alkaline sodium compounds are converted to solids by a process selected from the group: concentration, crystalization; evaporation, spray drying, solar evaporation; and combinations thereof.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein said treated leach liquor containing dissolved sodium compounds is concentrated before being contacted with carbon dioxide.
Claim 5
Dependent Claim
41 words
The method of claim 1 wherein said leaching of the soluble reaction products and the unreacted portion of said soluble alkaline sodium compounds includes washing said inert particulates essentially free of said soluble reaction products and said soluble alkaline sodium compounds.
Claim 6
Dependent Claim
51 words
The method of claim 1 wherein said precipitated stable calcium salts having anions including elements selected from the group sulfur and carbon to be discarded are separated from said leach liquor by thickening said leach liquor containing said calcium salts and filtering and washing said salts substantially free from sodium compounds.
Claim 7
Dependent Claim
33 words
The method of claim 1 wherein the step of converting the soluble sodium compounds to the solid state includes spray drying the solution containing said compounds under controlled conditions to form hollow spheres.
Claim 8
Dependent Claim
34 words
The method of claim 1 wherein said leaching of said reaction products and the unreacted portion of said alkaline sodium compounds from the inert particulate is accomplished by a multi-stage counter current leaching process.
Claim 9
Dependent Claim
23 words
The method of claim 1 wherein entrained water is removed from said waste gases subsequent to passing said gases through said filter means.
Claim 10
Dependent Claim
33 words
The method of claim 1 wherein the water vapor content of said waste gases passing through said filter means is in the range of from between about 2 and 20 percent by volume.
Claim 11
Independent Claim
347 words
A method for removal of sulfur dioxide and particulate contaminants from industrial waste gases prior to their discharge into the atmosphere, said method utilizing sulfur dioxide reactants of suitable activity which are subsequently regenerated, said method further resulting in stable insoluble sulfur containing compounds to be discarded, said method comprising: depositing soluble finely divided alkaline sodium compounds selected from the group: sodium carbonate, sodium bicarbonate, hydrated sodium carbonates, sodium sesquicarbonate, the naturally occuring ores, nahcolite and trona, containing said alkaline sodium compounds, and combinations thereof, on the filtering surfaces of a fabric tube type dust collector; passing waste gases having a water vapor content in the range of between about 2 and about 20 percent by volume and comprising sulfur dioxide, carbon dioxide and particulate contaminants through the filtering surfaces of said tube type dust collector whereupon a major portion of said sulfur dioxide reacts with said soluble finely divided alkaline sodium compounds on said filtering surfaces to form soluble reaction products; periodically removing said soluble reaction products, the unreacted portion of said soluble alkaline sodium compounds and said particulate contaminants from said filtering surfaces; leaching said soluble reaction products and said unreacted portion of said soluble alkaline sodium compounds from said inert particulates with water to effect separation thereof; treating the resultant leach water with calcium hydroxide to precipitate stable calcium salts, having anions including elements selected from the group: sulfur and carbon, to be discarded leaving dissolved sodium hydroxide in said leach water; reforming said soluble alkaline sodium compounds by reacting said dissolved sodium hydroxide with carbon dioxide from said previously treated waste gases; converting the reformed soluble alkaline sodium compounds to solids by a process selected from the group of concentration, crystalization, evaporation, spray drying, solar evaporation, and combinations thereof; preparing said solid, soluble, alkaline sodium compounds for reuse by drying, cooling and comminuting and; redepositing the resultant finely divided soluble alkaline sodium compounds onto said filtering surfaces of said fabric tube type dust collector thereby providing regenerated finely divided soluble alkaline sodium compounds for further reaction with sulfur dioxide in said waste gases.
Claim 12
Independent Claim
347 words
A method for removal of sulfur dioxide and particulate contaminants from industrial waste gases prior to their discharge into the atmosphere, said method utilizing sulfur dioxide reactants of suitable activity which are subsequently regenerated, said method further resulting in stable insoluble sulfur containing compounds to be discarded, said method comprising: depositing soluble finely divided alkaline sodium compounds selected from the group: sodium carbonate, sodium bicarbonate, hydrated sodium carbonates, sodium sesquicarbonate, the naturally occuring ores, nahcolite and trona, containing said alkaline sodium compounds, and combinations thereof, on the filtering surfaces of a fabric tube type dust collector; passing waste gases having a water vapor content in the range of between about 2 and about 20 percent by volume and comprising sulfur dioxide, carbon dioxide and particulate contaminants through the filtering surfaces of said tube type dust collector whereupon a major portion of said sulfur dioxide reacts with said soluble finely divided alkaline sodium compounds on said filtering surfaces to form soluble reaction products; periodically removing said soluble reaction products, the unreacted portion of said soluble alkaline sodium compounds and said particulate contaminants from said filtering surfaces; leaching said soluble reaction products and said unreacted portion of said soluble alkaline sodium compounds from said inert particulates with water to effect separation thereof; treating the resultant leach water with calcium hydroxide to precipitate stable calcium salts, having anions including elements selected from the group: sulfur and carbon, to be discarded leaving dissolved sodium hydroxide in said leach water; reforming said soluble alkaline sodium compounds by reacting said dissolved sodium hydroxide with carbon dioxide from said previously treated waste gases; converting the reformed soluble alkaline sodium compounds to solids by a process selected from the group of concentration, crystalization, evaporation, spray drying, solar evaporation, and combinations thereof; preparing said solid, soluble, alkaline sodium compounds for reuse by drying, cooling and comminuting and; redepositing the resultant finely divided soluble alkaline sodium compounds onto said filtering surfaces of said fabric tube type dust collector thereby providing regenerated finely divided soluble alkaline sodium compounds for further reaction with sulfur dioxide in said waste gases.
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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |