US3897540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of controlling reaction conditions in a sulfur dioxide scrubber
Assignee: American Air Filter Co Inc
•
Filing: 1973-03-07
•
Granted: 1975-07-29
•
Expires: 1993-03-07
Abstract
Abstract A process for treating industrial stack gases containing sulfur dioxide in the gas contact zone of a scrubbing tower with an aqueous medium containing a sulfur dioxide reactant material, which aqueous medium is subsequently removed from the contact zone and introduced into a reaction tank where the initial reaction product is oxidized to more stable reaction products. The process includes automatically controlling the pH of the liquid in the reaction tank, which automatic controlling includes monitoring the conditions in the reaction tank, comparing the information from the monitor to an optimum preselected condition and introducing a corrective portion of basic liquid into said reaction tank to attain the optimum preselected condition. The process further includes using the reaction tank as a supply reservoir for liquid introduced into the contact zone of the scrubbing tower, thus, insuring that the liquid introduced into the contact zone is of optimum pH for reaction.
Inventors
- 👤 James H Onnen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:11
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/501; Y; Y10; Y10T; Y10T436/00; Y10T436/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
273 words
A CONTINUOUS PROCESS FOR TREATING INDUSTRIAL STACK GASSES CONTAINING SULFUR DIOXIDE COMPRISING: CONTACTING SAID INDUSTRIAL STACK GASSES IN THE CONTACT ZONE OF GAS SCRUBBING TOWER WITH AN AQUEOUS MEDIUM CONTAINING A SULFUR DIOXIDE REACTANT MATERIAL, SAID SULFUR DIOXIDE REACTANT MATERIAL BEING AN ALKALINE METAL COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALCIUM HYDROXIDE, CALCIUM CARBONATE, CACIUM BICARBONATE, SODIUM BICARBONATE, THE NATURALLY OCCURING MATERIALS TRONA AND NAHCOLITE, AND COMBINATION THEREOF, WHEREUPON AN INITIAL REACTION PRODUCT IS FORMED, PASSING SAID AQUEOUS MEDIUM, CONTAINING PRINCIPALLY SAID INTIAL REACTION PRODUCT, FROM THE GAS SCRUBBING TOWER INTO THE UPSTREAM END OF A FILLED CONTINUOUSLY FLOWING REACTION TANK WHEREIN SAID INITIAL REACTION PRODUCT IS FURTHER REACTED, TO FORM A SECOND MORE STABLE REACTION PRODUCT AS SAID AQUEOUD MEDIUM FLOWS THROUGH SAID TANK, MONITIORING THE REACTION CONDITIONS AT A FIRST LOCATION IN SAID REACTION TANK AND AUTOMATICALLY ADJUSTING THE PH OF THE REACTION CONDITIONS BASED UPON A COMPARISON OF THE INFORMATION FROM SAID MONITORING TO A FIXED STANDARD IN A PH RANGE OF FROM ABOUT 2 TO 10, MONITORING THE REACTION CONDITIONS AT A SECOND LOCATION DOWNSTREAM OF THE FIRST IN THE REACTION RANK AND AUTOMATICALLY ADJUSTING THE PH OF THE REACTION CONDITIONS BASED UPON A COMPARISON OF THE INFOMATION FROM SAID MONITORING TO A SECOND FIXED STANDARD IN A PH RANGE OF FROM ABOUT 2 TO 10, CONTINOUSLY REMOVING A FIRST PORTION OF SAID AQUEOUS MEDIUM CONTAINING SAID SECOND REACTION PRODUCT FROM SAID REACTION TANK, REMOVING SAID SECOND REACTION PRODUCT FOR DISPOSAL AND REINTORDUCING SAID AQEOUS MEDIUM INTO SAID REACTION TANK, AND, CONTINUOUSLY RECIRCULATING A SECOND PORTION OF SAID AQUEOUS MEDIUM FROM SAID REACTION TANK TO SAID SCRUBBING TOWER.
Claim 2
Dependent Claim
273 words
A CONTINUOUS PROCESS FOR TREATING INDUSTRIAL STACK GASSES CONTAINING SULFUR DIOXIDE COMPRISING: CONTACTING SAID INDUSTRIAL STACK GASSES IN THE CONTACT ZONE OF GAS SCRUBBING TOWER WITH AN AQUEOUS MEDIUM CONTAINING A SULFUR DIOXIDE REACTANT MATERIAL, SAID SULFUR DIOXIDE REACTANT MATERIAL BEING AN ALKALINE METAL COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALCIUM HYDROXIDE, CALCIUM CARBONATE, CACIUM BICARBONATE, SODIUM BICARBONATE, THE NATURALLY OCCURING MATERIALS TRONA AND NAHCOLITE, AND COMBINATION THEREOF, WHEREUPON AN INITIAL REACTION PRODUCT IS FORMED, PASSING SAID AQUEOUS MEDIUM, CONTAINING PRINCIPALLY SAID INTIAL REACTION PRODUCT, FROM THE GAS SCRUBBING TOWER INTO THE UPSTREAM END OF A FILLED CONTINUOUSLY FLOWING REACTION TANK WHEREIN SAID INITIAL REACTION PRODUCT IS FURTHER REACTED, TO FORM A SECOND MORE STABLE REACTION PRODUCT AS SAID AQUEOUD MEDIUM FLOWS THROUGH SAID TANK, MONITIORING THE REACTION CONDITIONS AT A FIRST LOCATION IN SAID REACTION TANK AND AUTOMATICALLY ADJUSTING THE PH OF THE REACTION CONDITIONS BASED UPON A COMPARISON OF THE INFORMATION FROM SAID MONITORING TO A FIXED STANDARD IN A PH RANGE OF FROM ABOUT 2 TO 10, MONITORING THE REACTION CONDITIONS AT A SECOND LOCATION DOWNSTREAM OF THE FIRST IN THE REACTION RANK AND AUTOMATICALLY ADJUSTING THE PH OF THE REACTION CONDITIONS BASED UPON A COMPARISON OF THE INFOMATION FROM SAID MONITORING TO A SECOND FIXED STANDARD IN A PH RANGE OF FROM ABOUT 2 TO 10, CONTINOUSLY REMOVING A FIRST PORTION OF SAID AQUEOUS MEDIUM CONTAINING SAID SECOND REACTION PRODUCT FROM SAID REACTION TANK, REMOVING SAID SECOND REACTION PRODUCT FOR DISPOSAL AND REINTORDUCING SAID AQEOUS MEDIUM INTO SAID REACTION TANK, AND, CONTINUOUSLY RECIRCULATING A SECOND PORTION OF SAID AQUEOUS MEDIUM FROM SAID REACTION TANK TO SAID SCRUBBING TOWER.
Claim 3
Dependent Claim
56 words
The process of claim 1 wherein said second fixed standard is determined in part by information from the monitor at said first location in said reaction tank to insure that said second portion of said aqueous medium being recirculated to said scrubbing tower is at the optimum concentration for reaction with the industrial stack gases therein.
Claim 4
Dependent Claim
40 words
The process of claim 1 wherein said sulfur dioxide reactant material is an alkaline metal compound selected from the group calcium hydroxide, calcium carbonate, calcium bicarbonate, sodium carbonate, sodium bicarbonate, the naturally occurring materials torona and nahcolite, and combinations thereof.
Claim 5
Dependent Claim
27 words
The process of claim 1 wherein the pH of the reaction conditions are adjusted to a pH of between about 2 and 10 on the pH scale.
Claim 6
Dependent Claim
49 words
The process of claim 1 wherein said industrial stack gases comprise a plurality of gas streams each of which is independently treated in a separate scrubbing system each of said scrubbing systems having independent pH monitoring and adjusting means for the aqueous medium containing sulfur dioxide reactant circulated therein.
References Cited (Backward Citations)
US2113198A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |