US4367065A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for firing coal in pyro-processes using direct heat recuperation from a cross flow heat exchanger
Assignee: Allis Chalmers Corp
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Filing: 1981-02-23
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Granted: 1983-01-04
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Expires: 2001-02-23
Abstract
Abstract Coal is placed upon hot mineral solids being cooled by an upward flow of ambient air; the coal is dried, ignited and completely combusted under process conditions associated with cooling after firing. The hot off-gas from cooling is returned directly to the firing section or other sections of the process as heat.
Inventors
- 👤 Robert F. Cnare
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:12
CPC Classifications
F; F27; F27B; F27B7/00; F27B7/20; F27B7/2016; F27B7/38; F27B7/383
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
218 words
A method of treating material in a pyro-process system in which the material is processed through at least a final heat treatment zone and a cooling treatment zone in which the material received from the final heat treatment zone is formed into a relatively level bed and cooled by an updraft of air passing through the bed, comprising the steps of: A. supplying said material to said cooling zone at a temperature which will ignite coal; B. adding a quantity of coal particles on top of the material bed in the cooling zone, with at least a major portion of the particles being of a minimum size large enough to remain on the bed with the updraft of air passing through the bed; C. adjusting the velocity of the updraft air through the bed to maintain the velocity of off-gases emerging upwardly from the bed below the velocity required to entrain in said off-gases more than a minor portion of ash formed by combustion of the coal on the bed; D. maintaining the coal on the material bed in the cooling zone for a period of time sufficient to burn the coal and heat the off-gases; and E. returning the heated off-gases from the combusted coal and said material to the final heat treating zone as system heat.
Claim 2
Independent Claim
218 words
A method of treating material in a pyro-process system in which the material is processed through at least a final heat treatment zone and a cooling treatment zone in which the material received from the final heat treatment zone is formed into a relatively level bed and cooled by an updraft of air passing through the bed, comprising the steps of: A. supplying said material to said cooling zone at a temperature which will ignite coal; B. adding a quantity of coal particles on top of the material bed in the cooling zone, with at least a major portion of the particles being of a minimum size large enough to remain on the bed with the updraft of air passing through the bed; C. adjusting the velocity of the updraft air through the bed to maintain the velocity of off-gases emerging upwardly from the bed below the velocity required to entrain in said off-gases more than a minor portion of ash formed by combustion of the coal on the bed; D. maintaining the coal on the material bed in the cooling zone for a period of time sufficient to burn the coal and heat the off-gases; and E. returning the heated off-gases from the combusted coal and said material to the final heat treating zone as system heat.
Claim 3
Dependent Claim
37 words
A method according to claim 1 in which step B includes adding the coal onto the material bed across the entire width of the moving material bed transverse to the direction of movement of the material bed.
Claim 4
Dependent Claim
40 words
A method according to claim 1 in which the coal added to the material bed in the cooling zone according to step B is deposited adjacent the area wherein the material from the heat treatment zone enters the cooling zone.
Claim 5
Dependent Claim
38 words
A method according to claim 1 in which the off-gas from the combusted coal in the cooling zone is withdrawn from the cooling zone at a position adjacent to where the coal off-gas is at its highest temperature.
Claim 6
Dependent Claim
24 words
A method according to claim 1 in which the coal that is added onto the material bed in the cooling zone is crushed coal.
Claim 7
Dependent Claim
35 words
A method according to claim 1 in which the quantity of coal added to the material bed in the cooling zone will supply approximately 25 to 40 percent of a pyro-process system total fuel requirement.
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) | 1986-01-03 | 1986-07-05 | 1987-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-03 | 1990-07-05 | 1991-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-03 | 1994-07-05 | 1995-01-04 | $7700.00 | Window Closed / Lapsed |