Patent US3870652A successfully refreshed from Google Patents.
US3870652A
Expired / Lapsed
US
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Production of activated char using a moving grate stoker furnace
Assignee: Peabody Development Co
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Filing: 1973-08-13
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Granted: 1975-03-11
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Expires: 1993-08-13
Abstract
Abstract Carbonaceous material is deposited so as to form a bed on a grate moving horizontally through a hot furnace, the furnace having a zoned airbox beneath the grate. Hot combustion byproduct gases are downdrafted through the bed as it passes over airbox zones which are disposed towards the entrance end of the furnace so as to dry and ignite the material and sweep off volatiles therefrom. Air and steam and next air alone and finally steam is fed upwardly through the bed as it progresses beyond the downdrafted zones. Over the bed at the end of the grate run, the downdrafted gases are injected back into the furnace above the bed and burned, and finally the then charred material is quenched by a water spray.
Inventors
- 👤 Charles M Whitten
- 👤 Robert G Hagstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:03
CPC Classifications
C; C10; C10B; C10B49/00; C10B49/02; C10B49/04; C01; C01B; C01B32/00; C01B32/30; C01B32/312; C01B32/336; Y; Y02; Y02P; Y02P20/00; Y02P20/10; Y02P20/129
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
232 words
The method of making activated carbon from a carbonaceous starting material selected from the class consisting of wood, peat, brown coal, lignite, subbituminous coal, bituminous coal, semi-anthracite coal and antracite coal, which method comprises, continuously depositing said starting material onto a continuously moving grate running horizontally from front to rear through a hot carbonizing furnace and, in so doing, passes over a series of first, second and third airbox zone means consecutively arranged from front to rear of the furnace, downdrafting hot gases through the bed from above that portion of the bed which is disposed towards the rear of the furnace from the first airbox zone means as the bed moves over first airbox zone means so as to drive off moistuure and volatile matter from and pre-heat the material, simultaneously feeding air upwardly through the bed as the latter passes over the second airbox zone means and thereby raising the bed temperature from the pre-heat temperature to a charring temperature, simultaneously feeding steam upwardly through the bed as the latter passes over third airbox zone means so as to reduce the bed temperature, and simultaneously feeding the downdrafted gases ladened with moisture and volatile matter into the rear portion of the furnace over that portion of the bed which is then passing over the third airbox zone means and thereby maintaining a reducing atmosphere in the furnace over the bed.
Claim 2
Independent Claim
232 words
The method of making activated carbon from a carbonaceous starting material selected from the class consisting of wood, peat, brown coal, lignite, subbituminous coal, bituminous coal, semi-anthracite coal and antracite coal, which method comprises, continuously depositing said starting material onto a continuously moving grate running horizontally from front to rear through a hot carbonizing furnace and, in so doing, passes over a series of first, second and third airbox zone means consecutively arranged from front to rear of the furnace, downdrafting hot gases through the bed from above that portion of the bed which is disposed towards the rear of the furnace from the first airbox zone means as the bed moves over first airbox zone means so as to drive off moistuure and volatile matter from and pre-heat the material, simultaneously feeding air upwardly through the bed as the latter passes over the second airbox zone means and thereby raising the bed temperature from the pre-heat temperature to a charring temperature, simultaneously feeding steam upwardly through the bed as the latter passes over third airbox zone means so as to reduce the bed temperature, and simultaneously feeding the downdrafted gases ladened with moisture and volatile matter into the rear portion of the furnace over that portion of the bed which is then passing over the third airbox zone means and thereby maintaining a reducing atmosphere in the furnace over the bed.
Claim 3
Independent Claim
184 words
THE METHOD OF MAKING ACTIVATED CARBON FROM A CARBONACEOUS STARTING MATERIAL SELECTED FROM THE CLASS CONSISTING OF WOOD, PEAT, BROWN COAL LIGNITE, SUBBITUMINOUS COAL, BITUMINOUS COAL, SEMI-ANTHRACITE COAL AND ANTRACITE COAL, WHICH METHOD COMPRISES, CONTINUOUSLY DEPOSITING SAID STARTING MATERIAL ONTO A CONTINUOUSLY MOVING GRATE RUNNING HORIZONTALLY FROM FRONT TO REAR THROUGH A HOT CARBONIZING FURNACE AND, IN SO DOING, PASSES OVER A SERIES OF FIRST, SECOND AND THIRD AIRBOX ZONE MEANS CONSECUTIVELY ARRANGED FROM FRONT TO REAR OF THE FURNACE, DOWNDRAFTING HOT GASES THROUGH THE BED FROM ABOVE THAT PORTION OF THE BED WHICH DISPOSED TOWARDS THE REAR OF THE FURNACE FROM THE AIRBOX ZONE MEANS AS THE BED MOVES OVER FIRST AIRBOX ZONE MEANS SO AS TO DRIVE OFF MOISTURE AND VOLATILE MATTER FROM AND PRE-HEAT THE MATERIAL, SIMULTANEOUSLY FEEDING AIR UPWARDLY THROUGH THE BED AS THE LATTER PASSES OVER THE SECOND AIRBOX ZONE MEANS AND THEREBY RAISING THE BED TEMPERATURE FROM THE PRE-HEAT TEMPERATURE TO A CHARRING TEMPERATURE, SIMULTANEOUSLY FEEDING STEAM UPWARDLY THROUGH THE BED AS THE LATTER PASSES OVER THIRD AIRBOX ZONE MEANS SO AS TO REDUCE THE BED TEMPERATURE, AND
Claim 4
Independent Claim
184 words
THE METHOD OF MAKING ACTIVATED CARBON FROM A CARBONACEOUS STARTING MATERIAL SELECTED FROM THE CLASS CONSISTING OF WOOD, PEAT, BROWN COAL LIGNITE, SUBBITUMINOUS COAL, BITUMINOUS COAL, SEMI-ANTHRACITE COAL AND ANTRACITE COAL, WHICH METHOD COMPRISES, CONTINUOUSLY DEPOSITING SAID STARTING MATERIAL ONTO A CONTINUOUSLY MOVING GRATE RUNNING HORIZONTALLY FROM FRONT TO REAR THROUGH A HOT CARBONIZING FURNACE AND, IN SO DOING, PASSES OVER A SERIES OF FIRST, SECOND AND THIRD AIRBOX ZONE MEANS CONSECUTIVELY ARRANGED FROM FRONT TO REAR OF THE FURNACE, DOWNDRAFTING HOT GASES THROUGH THE BED FROM ABOVE THAT PORTION OF THE BED WHICH DISPOSED TOWARDS THE REAR OF THE FURNACE FROM THE AIRBOX ZONE MEANS AS THE BED MOVES OVER FIRST AIRBOX ZONE MEANS SO AS TO DRIVE OFF MOISTURE AND VOLATILE MATTER FROM AND PRE-HEAT THE MATERIAL, SIMULTANEOUSLY FEEDING AIR UPWARDLY THROUGH THE BED AS THE LATTER PASSES OVER THE SECOND AIRBOX ZONE MEANS AND THEREBY RAISING THE BED TEMPERATURE FROM THE PRE-HEAT TEMPERATURE TO A CHARRING TEMPERATURE, SIMULTANEOUSLY FEEDING STEAM UPWARDLY THROUGH THE BED AS THE LATTER PASSES OVER THIRD AIRBOX ZONE MEANS SO AS TO REDUCE THE BED TEMPERATURE, AND
Claim 5
Dependent Claim
24 words
The method recited in claim 1, wherein the bed temperature, in passing over the second airbox zone means, is raised to about 1580* F.
Claim 6
Dependent Claim
47 words
The method recited in claim 2, including the step of feeding steam upwardly through the bed while the latter passes over at least part of the second airbox zone means so as to reduce the amount of combustion produced in the bed by the air fed therethrough.
Claim 7
Dependent Claim
22 words
The method recited in claim 3, wherein the bed is quenched to about 780* while passing over the third airbox zone means.
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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |