Patent US3620514A successfully refreshed from Google Patents.
US3620514A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel-air fired furnace with supplemental oxygen-fuel burner
Assignee: Airco Inc
•
Filing: 1969-10-08
•
Granted: 1971-11-16
•
Expires: 1989-10-08
Abstract
Abstract A furnace for melting a load of metal scrap containing pig iron, etc., having at one end two laterally spaced main coal-air burners for directing flames to the load, the projected axes of the respective burners converging and intersecting approximately at the midportion of the furnace near the load level, and a supplemental oxygen-fuel burner of heat generating capacity materially less than the combined capacities of the main coal-air burners, located between and beneath the main burners for directing an oxygen-fuel flame approximately at the point of intersection of the coal-air flames.
Inventors
- 👤 Lewis J Geiger Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:37
CPC Classifications
F; F27; F27B; F27B3/00; F27B3/10; F27B3/20
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
148 words
In a fuel-air fired furnace having at least two main fuel-air burners in a furnace wall for projecting heating flames therefrom to a furnace load, the process for accelerating transfer of heat from the flames to the load over an extended area thereof which comprises: a. directing the projected main fuel-air flames from at least two of said fuel-air burners for convergence along the longitudinal midportion of the furnace in heat transfer relation to the load surface, b. projecting in the same general direction a supplemental hightemperature oxygen-fuel flame at a velocity higher than that of the main flames into the convergence of the said main flames for producing progressive flame interaction and materially increased heat transfer between the main flames and the furnace load, c. and proportioning the heat-generating capacity of the oxygenfuel flame to a minor fraction of the total capacity of the main fuel-air flames.
Claim 2
Dependent Claim
148 words
In a fuel-air fired furnace having at least two main fuel-air burners in a furnace wall for projecting heating flames therefrom to a furnace load, the process for accelerating transfer of heat from the flames to the load over an extended area thereof which comprises: a. directing the projected main fuel-air flames from at least two of said fuel-air burners for convergence along the longitudinal midportion of the furnace in heat transfer relation to the load surface, b. projecting in the same general direction a supplemental hightemperature oxygen-fuel flame at a velocity higher than that of the main flames into the convergence of the said main flames for producing progressive flame interaction and materially increased heat transfer between the main flames and the furnace load, c. and proportioning the heat-generating capacity of the oxygenfuel flame to a minor fraction of the total capacity of the main fuel-air flames.
Claim 3
Dependent Claim
37 words
The method as specified in claim 1 wherein the supplemental oxygen-fuel flame is projected as a stiff jet at about sound velocity for interacting contact with the lower velocity main fuel-air flames along an expanding fuel-oxidizing region.
Claim 4
Dependent Claim
31 words
The method as specified in claim 2 wherein the supplemental flame is angularly directed from beneath the main flames into making gradually increasing contact therewith for establishing the expanding fuel-oxidizing region.
Claim 5
Dependent Claim
33 words
The method as specified in claim 1 wherein the main and supplemental flames are initially directed along respective projected axes that lie in two planes intersecting along the midportion of the load surface.
Claim 6
Dependent Claim
32 words
The method as specified in claim 4 wherein the supplemental flame is directed along an axis making with the load surface an acute angle smaller than those made by the main axes.
Claim 7
Dependent Claim
56 words
The method as specified in claim 1 wherein the fuel air flames are projected over a part of the load surface and the high-velocity oxygen-fuel flame is projected between the fuel-air flames and load surface whereby the fuel-air flames are inducted into an expanding high-temperature region of flame interaction for achieving high rate of fuel oxidation.
Claim 8
Dependent Claim
47 words
The method as specified in claim 6 wherein the expanding region of flame interaction is formed directly above an extended area of the load surface for causing impingement thereon of the resulting high temperature, high-velocity combustion product gasses with high rate of heat transfer to the load.
Claim 9
Dependent Claim
55 words
The method as specified in claim 7 wherein the fuel in the main fuel-air flame is powdered coal, the fuel in the supplemental oxygen flame is natural gas, and the partially burned components and coal particles of the main flames are progressively drawn downwardly by inductive action into the expanding fuel-oxidizing region for complete combustion.
Claim 10
Dependent Claim
92 words
A fuel-air fired furnace for the direct transfer of flame heat to the furnace load comprising: a. a pair of main fuel-air burners at one end of the furnace for projecting respective heating flames tending to converge and coalesce in heat transfer relation to the load surface, b. and a supplemental oxygen-fuel burner symmetrically mounted with respect to the main burners for projecting a comparatively stiff oxygen-fuel flame generally along and into the convergence of the main flames for progressively increasing contact therewith along an extended longitudinal section of the load surface.
Claim 11
Dependent Claim
92 words
A fuel-air fired furnace for the direct transfer of flame heat to the furnace load comprising: a. a pair of main fuel-air burners at one end of the furnace for projecting respective heating flames tending to converge and coalesce in heat transfer relation to the load surface, b. and a supplemental oxygen-fuel burner symmetrically mounted with respect to the main burners for projecting a comparatively stiff oxygen-fuel flame generally along and into the convergence of the main flames for progressively increasing contact therewith along an extended longitudinal section of the load surface.
Claim 12
Dependent Claim
35 words
A fuel-air fired furnace as specified in claim 9 wherein the main burners are horizontally spaced at a common level and the supplemental burner is in an intermediate position with respect to the main burners.
Claim 13
Dependent Claim
36 words
A fuel-air fired furnace as specified in claim 10 wherein the supplemental burner is offset below the horizontal level of the main burners for projecting the oxygen-fuel flame into the underside of the coalesced main flames.
Claim 14
Dependent Claim
71 words
A fuel-air fired furnace as specified in claim 9 wherein the fuel is powdered coal and the respective burners are angularly positioned for initially causing the coal-air flames partially to cover and surround the high-velocity supplemental flame, and for producing in the general region of convergence a region of extensive interacting contact between the supplemental and main flames within which high-temperature oxidation of coal particles from the main flames is completed.
Claim 15
Dependent Claim
39 words
A fuel-air fired furnace as specified in claim 12 wherein the stiff supplemental flame progressively draws coal and unburned carbon particles into an expanding generally conical high-temperature region of complete combustion spanning an extensive midportion of the load surface.
Claim 16
Dependent Claim
56 words
A fuel-air fired furnace as specified in claim 13 wherein the flame temperature in the region of initial interacting flame contact is approximately 5,000* F., and the temperature in the diverging part of the conical region is approximately 2,600* F., for establishing high rate of heat transfer to the load surface over an extended area thereof.
Claim 17
Dependent Claim
105 words
A furnace for melting a metal charge comprising a refractory-lined enclosure adapted to contain said charge and the resulting molten metal bath, a pair of air-fuel burners mounted in the wall portion of said enclosure, means mounting said air-fuel burners to direct converging and coalescing air-fuel flames into said enclosure to reduce the metal charge, a supplemental oxyfuel burner mounted in the wall portion of said enclosure, means mounting said oxyfuel burner to direct a high-temperature, high-velocity oxyfuel flame into the lower portions of the coalescing air-fuel flames, to thereby create an aspirating effect which tends to draw the air-fuel flames into the oxyfuel flame.
Claim 18
Dependent Claim
105 words
A furnace for melting a metal charge comprising a refractory-lined enclosure adapted to contain said charge and the resulting molten metal bath, a pair of air-fuel burners mounted in the wall portion of said enclosure, means mounting said air-fuel burners to direct converging and coalescing air-fuel flames into said enclosure to reduce the metal charge, a supplemental oxyfuel burner mounted in the wall portion of said enclosure, means mounting said oxyfuel burner to direct a high-temperature, high-velocity oxyfuel flame into the lower portions of the coalescing air-fuel flames, to thereby create an aspirating effect which tends to draw the air-fuel flames into the oxyfuel flame.
References Cited (Backward Citations)
US1513828A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |