US3884620A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and apparatus for continuously heating fine-grained coal
Assignee: GEA Group AG
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Filing: 1973-10-10
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Granted: 1975-05-20
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Expires: 1993-10-10
Abstract
Abstract Fine-grained coal is continuously heated to a controlled, uniform end temperature by direct contact with hot gases by conveying the coal to be heated to a first elevated heat exchange cyclone and subsequently to one or more heat exchange cyclones positioned on a lower level or on successively lower levels, the temperature of the coal being raised in the cyclones. Thereafter the coal is heated to the end temperature in a fluidized bed heater and the exhaust gas from the fluidized bed heater is supplied as a hot conveying gas to the heat exchange cyclones positioned above the fluidized bed heater. Apparatus for carrying out the process of the invention includes a plurality of heat exchange cyclones for preheating the coal positioned on different levels, a fluidized bed heater positioned below the heat exchange cyclones and means to transfer exhaust gas from the fluidized bed heater to the heat exchange cyclones. A dust collector is also included for collecting fine dust from the exhaust gas leaving the upper most heat exchange cyclone.
Inventors
- 👤 Roland Rammler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:09
CPC Classifications
F; F26; F26B; F26B17/00; F26B17/10; F26B17/101; C; C10; C10B; C10B49/00; C10B49/02; C10B49/04; C10B49/08; C10B57/00; C10B57/08; C10B57/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
133 words
Process for continuously heating fine-grained coal to a controlled, uniform end temperature by direct contact with hot gases which comprises conveying the coal to be heated to elevated cyclonic zone and subsequently to one or more cyclonic heat exchange zones disposed on a lower level or on successively lower levels, the temperature of the coal being raised in said heat exchange zones, thereafter heating the coal to said end temperature in a fluidiZed-bed heating zone, the exhaust gas from the fluidized-bed heating zone being supplied to a separate cyclonic collecting zone where dust is collected from the exhaust gas, said gas being then passed as a hot conveying gas through said one or more heat exchange zones, said dust collected in the collecting zone being withdrawn or recycled to the fluidized bed zone.
Claim 2
Dependent Claim
133 words
Process for continuously heating fine-grained coal to a controlled, uniform end temperature by direct contact with hot gases which comprises conveying the coal to be heated to elevated cyclonic zone and subsequently to one or more cyclonic heat exchange zones disposed on a lower level or on successively lower levels, the temperature of the coal being raised in said heat exchange zones, thereafter heating the coal to said end temperature in a fluidiZed-bed heating zone, the exhaust gas from the fluidized-bed heating zone being supplied to a separate cyclonic collecting zone where dust is collected from the exhaust gas, said gas being then passed as a hot conveying gas through said one or more heat exchange zones, said dust collected in the collecting zone being withdrawn or recycled to the fluidized bed zone.
Claim 3
Dependent Claim
21 words
Process of claim 1 wherein a suspended-particle drying zone is used to convey the coal to the first heat exchange zone.
Claim 4
Dependent Claim
26 words
Process of claim 1 wherein the residence time of the coal in the fluidized-bed heating zone is between a few minutes and about half an hour.
Claim 5
Dependent Claim
27 words
Process of claim 1 wherein said hot conveying gas is conducted in flow paths opposite to the direction in which the coal being heated flows under gravity.
Claim 6
Dependent Claim
31 words
Process of claim 1 wherein fine dust is collected from the vapor leaving the dryer and from exhaust gas leaving the first heat exchange zone which is combined with said vapor.
Claim 7
Dependent Claim
24 words
Process of claim 1 wherein moist coal to be heated to an end temperature above 500*C. is dried in the first heat exchange zone.
Claim 8
Dependent Claim
46 words
Process of claim 1 wherein the fluidizing gas required for the fluidized-bed zone is produced in a preceding combustion zone wherein an almost stoichiometric fuel gas to air ratio is maintained and the fluidizing gas is temperature-conditioned by an addition of cooled and recycled exhaust gas.
Claim 9
Dependent Claim
22 words
Process of claim 1 wherein an internal combustion is carried out in said fluidized-bed zone to obtain an end temperature above 500*C.
Claim 10
Dependent Claim
133 words
Apparatus for heating fine-grained coal to a controlled, uniform end temperature by direct contact with hot gases which comprises means to convey coal to be heated to elevated cyclone means, a plurality of cyclonic heat exchange means for preheating the coal positioned on different levels below said elevated cyclone means, fluidized bed means as a final heating stage, means to supply said bed with fluidizing gas, means for transferring exhaust gas from the fluidized-bed means into the heat exchange means including cyclonic collecting means between the fluidized bed means and the lowermost cyclonic heat exchange means for collecting dust from said exhaust gas and withdrawing or recycling the collected dust to the fluidized bed means, and dust collecting means for collecting fine dust from the exhaust gas leaving the uppermost heat exchange means.
Claim 11
Dependent Claim
133 words
Apparatus for heating fine-grained coal to a controlled, uniform end temperature by direct contact with hot gases which comprises means to convey coal to be heated to elevated cyclone means, a plurality of cyclonic heat exchange means for preheating the coal positioned on different levels below said elevated cyclone means, fluidized bed means as a final heating stage, means to supply said bed with fluidizing gas, means for transferring exhaust gas from the fluidized-bed means into the heat exchange means including cyclonic collecting means between the fluidized bed means and the lowermost cyclonic heat exchange means for collecting dust from said exhaust gas and withdrawing or recycling the collected dust to the fluidized bed means, and dust collecting means for collecting fine dust from the exhaust gas leaving the uppermost heat exchange means.
Claim 12
Dependent Claim
16 words
Apparatus of claim 9 wherein said fluidized-bed means includes means for carrying out an internal combustion.
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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |