US4499945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silane-propane ignitor/burner
Assignee: United States, DOE THE, Secretary of
•
Filing: 1983-05-26
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Granted: 1985-02-19
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Expires: 2003-05-26
Abstract
Abstract A silane propane burner for an underground coal gasification process which is used to ignite the coal and to controllably retract the injection point by cutting the injection pipe. A narrow tube with a burner tip is positioned in the injection pipe through which an oxidant (oxygen or air) is flowed. A charge of silane followed by a supply of fuel, such as propane, is flowed through the tube. The silane spontaneously ignites on contact with oxygen and burns the propane fuel.
Inventors
- 👤 Richard W. Hill
- 👤 Dewey F. Skinner
- 👤 Charles B. Thorsness
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:50
CPC Classifications
E; E21; E21B; E21B36/00; E21B36/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
130 words
Apparatus for producing a controlled burn in an injection pipe in a horizontal borehole in an underground coal gasification process, comprising: a small diameter retractable tube which is insertable into the borehole; a burner tip on the tube which is positioned at the point where the controlled burn is desired to ignite coal or cut the pipe; and gas supply means operatively connected to the tube including a first gas supply means to provide a charge of pyrophoric gas through the tube to the burner tip to contact oxygen containing combustion supporting gas in the pipe and thereby ignite, and a second gas supply means to provide a flow of combustible fuel gas through the tube following the charge of pyrophoric gas to be ignited by the burning pyrophoric gas.
Claim 2
Dependent Claim
130 words
Apparatus for producing a controlled burn in an injection pipe in a horizontal borehole in an underground coal gasification process, comprising: a small diameter retractable tube which is insertable into the borehole; a burner tip on the tube which is positioned at the point where the controlled burn is desired to ignite coal or cut the pipe; and gas supply means operatively connected to the tube including a first gas supply means to provide a charge of pyrophoric gas through the tube to the burner tip to contact oxygen containing combustion supporting gas in the pipe and thereby ignite, and a second gas supply means to provide a flow of combustible fuel gas through the tube following the charge of pyrophoric gas to be ignited by the burning pyrophoric gas.
Claim 3
Dependent Claim
26 words
The apparatus of claim 1 wherein the gas supply means further includes a third gas supply means to flow an inert purging gas through the tube.
Claim 4
Dependent Claim
20 words
The apparatus of claim 2 wherein the gas supply means is a supply of gas selected from nitrogen and argon.
Claim 5
Dependent Claim
16 words
The apparatus of claim 1 wherein the first gas supply means is a supply of silane.
Claim 6
Dependent Claim
28 words
The apparatus of claim 4 wherein the silane supply is a supply of silane gas mixture with a silane concentration between the lower flamability limit and detonation limit.
Claim 7
Dependent Claim
21 words
The apparatus of claim 1 wherein the second gas supply means is a supply of gas selected from propane and methane.
Claim 8
Dependent Claim
34 words
The apparatus of claim 1 further including gas flow regulation means operatively connected to the second gas supply means to delay and regulate the flow of fuel gas after the charge of pyrophoric gas.
Claim 9
Dependent Claim
13 words
The apparatus of claim 7 wherein the regulator means is a needle valve.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |