US4776289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for burning pulverized solid fuel
Assignee: DISEL & COMBUSTION TECHNOLOGIES LLC
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Filing: 1987-06-18
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Granted: 1988-10-11
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Expires: 2007-06-18
Abstract
Abstract A process and apparatus are described with which pulverized coal can be burned with an essentially non-turbulent flame in which the residence time of individual cool particles within the burner flame is generally increased. Pulverized cool is supplied through a plurality of annularly-distributed conduits. A supply of secondary air is passed around the conduits in a manner so as to produce an axial or low turbulent flow of air from the burner with a relatively small amount of the combustion air being swirled to produce a vortex suitable to anchor the burner flame. The pulverized solid fuel is injected to enter both the vortex and flame regions so as to expose a large portion of fuel particles to a low turbulent diffusion flame in which oxygen reaches burning particles primarily by way of a diffusion process.
Inventors
- 👤 Jeremy Peter-Hoblyn
- 👤 Normand A. Brais
- 👤 Francois X. Grimard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:25
CPC Classifications
F; F23; F23D; F23D1/00; F23D1/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
145 words
A process for burning pulverized solid fuel in the flame of a burner comprising the simultaneous steps of: supplying combustion air to the discharge end of the burner so as to produce a vortex that is sufficient to stabilize the burner flame in a region in front of the burner; delivering a pulverized solid fuel, formed of particles, to a discharge end of the burner through a plurality of separate conduits that are distributed around the combustion air vortex; passing combustion air around the solid fuel delivering conduits to establish an axial gas flow from the burner along the flame region; and discharging the pulverized solid fuel from the conduits in a direction as will inject the particles into the axial flow part of the flame region as well as into the vortex to establish a pulverized solid-fuelfed elongated flame with enhanced particle residence time.
Claim 2
Dependent Claim
145 words
A process for burning pulverized solid fuel in the flame of a burner comprising the simultaneous steps of: supplying combustion air to the discharge end of the burner so as to produce a vortex that is sufficient to stabilize the burner flame in a region in front of the burner; delivering a pulverized solid fuel, formed of particles, to a discharge end of the burner through a plurality of separate conduits that are distributed around the combustion air vortex; passing combustion air around the solid fuel delivering conduits to establish an axial gas flow from the burner along the flame region; and discharging the pulverized solid fuel from the conduits in a direction as will inject the particles into the axial flow part of the flame region as well as into the vortex to establish a pulverized solid-fuelfed elongated flame with enhanced particle residence time.
Claim 3
Dependent Claim
48 words
The burning process as claimed in claim 1 wherein the vortex producing step further comprises: directing an amount of combustion air through a vortex generator where the amount is generally less than about twenty-five percent (25%) of the total amount of combustion air delivered to the flame region.
Claim 4
Dependent Claim
40 words
The burning process as claimed in claim 2 wherein the step of discharging the pulverized solid fuel includes: deflecting solid fuel delivered through the conduits toward the flame region in a solid angle that includes the vortex of the flame.
Claim 5
Dependent Claim
40 words
The burning process as claimed in claim 3 and further including reducing the amount of combustion air and pulverized solid fuel in a range that extends to about one-fifth of full load operation while preserving the integrity of the flame.
Claim 6
Dependent Claim
60 words
The burning process as claimed in claim 1 wherein the solid fuel is delivered through the conduits with a carrier of primary air and where the amount of primary air through the conduits is generally in the range from about ten percent (10%) to about twenty-five percent (25%) of the total amount of combustion air delivered to the flame region.
Claim 7
Dependent Claim
98 words
In a burner for the burning of pulverized solid fuel in an axial flow burner wherein a plurality of fuel conduits are arranged around a vortex generating section and are located inside a combustion air chamber from which air is projected to produce an axial flow in a flame region that is anchored to a stable location by a vortex produced by the vortex generating section, the improvement comprising: means for removably-mounting the fuel conduits inside the burner, said fuel conduits terminating at open discharge ends having deflecting walls oriented to discharge pulverized solid fuel at the vortex.
Claim 8
Dependent Claim
98 words
In a burner for the burning of pulverized solid fuel in an axial flow burner wherein a plurality of fuel conduits are arranged around a vortex generating section and are located inside a combustion air chamber from which air is projected to produce an axial flow in a flame region that is anchored to a stable location by a vortex produced by the vortex generating section, the improvement comprising: means for removably-mounting the fuel conduits inside the burner, said fuel conduits terminating at open discharge ends having deflecting walls oriented to discharge pulverized solid fuel at the vortex.
Claim 9
Dependent Claim
20 words
The improved pulverized solid fuel burner as claimed in claim 6 wherein the solid fuel conduits have removable end sections.
Claim 10
Dependent Claim
22 words
The improved pulverized solid fuel burner as claimed in claim 6 wherein the solid fuel conduits end sections have unobstructed discharge openings.
Claim 11
Dependent Claim
18 words
The improved pulverized solid fuel burner as claimed in claim 8 wherein the solid fuel conduits are tubular.
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) | 1991-10-11 | 1992-04-11 | 1992-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-11 | 1996-04-11 | 1996-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-11 | 2000-04-11 | 2000-10-11 | $7700.00 | Window Closed / Lapsed |