EP0007697A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Burner system for gaseous and/or liquid fuels with a minimum production of NOx
Assignee: Zinklahoma Inc
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Filing: 1979-06-15
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Granted: —
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Expires: 1999-06-15
Abstract
Abstract A low NOx burner (10) for a furnace operating under natural draught in which primary and secondary combustion air (60, 62) are provided to a first burning zone (16,18) in which either or both liquid and gaseous fuel can be used. Less than stoichiometric air is supplied in the primary burning zone (16, 18 and tertiary combustion air (50) is supplied in a second cor bustion zone (28) downstream from the first combustion zon (16, 18). The total air supply is over the stoichiometric requirement. Air control means (38,40,42 and 44) is provided so that a fixed ratio of primary-secondary air/tertiary air is provided for all burning and fuel rate conditions, so as to maintain the less than stoichiometric air supply to the first combustion zone. In addition, water atomization (68, 70, 88 and 89) is provided upstream of the first burning zone (16,18) to provide a burning chemistry which factors the reduction of NOx in the first burning zone.
Inventors
- 👤 Robert D. Reed
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 13:47
CPC Classifications
F; F23; F23L; F23L7/00; F23L7/002; F23C; F23C6/00; F23C6/04; F23C6/045; F23C6/047; F23D; F23D17/00; F23D17/002; F23C2201/00; F23C2201/20; F23C2201/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
148 words
1 . A fluid fuel burner system for minimum production of NOx under varying rates of fuel firing comprising a fuel burner system and means for supplying primary and secondary combustion air thereto, characterized in that means are provided to ignite the fuel from the fuel burner system (10) to provide a flame in a primary combustion space (16, 18) for which the primary (60) and secondary (62) combustion air is a selected fraction FT of the total combustion air flow rate T, means for supplying tertiary combustion air (50) in a ratio (1-F)T of the total combustion air flow rate T, delivered to a secondary combustion space (28) downstream of the first combustion space (16, 18) and means to control the total combustion air flow rate T over a selected range, while maintaining the primary plus secondary and tertiary combustion air flow rates FT and (1-F)T, respectively.
Claim 2
Dependent Claim
148 words
1 . A fluid fuel burner system for minimum production of NOx under varying rates of fuel firing comprising a fuel burner system and means for supplying primary and secondary combustion air thereto, characterized in that means are provided to ignite the fuel from the fuel burner system (10) to provide a flame in a primary combustion space (16, 18) for which the primary (60) and secondary (62) combustion air is a selected fraction FT of the total combustion air flow rate T, means for supplying tertiary combustion air (50) in a ratio (1-F)T of the total combustion air flow rate T, delivered to a secondary combustion space (28) downstream of the first combustion space (16, 18) and means to control the total combustion air flow rate T over a selected range, while maintaining the primary plus secondary and tertiary combustion air flow rates FT and (1-F)T, respectively.
Claim 3
Dependent Claim
20 words
A burner system according to claim 1, characterized in that the fuel burner system is a liquid fuel system (12).
Claim 4
Dependent Claim
21 words
A burner system according to claim 1, characterized in that the fuel burner system is a gaseous fuel burner system (14).
Claim 5
Dependent Claim
26 words
A burner system according to claim 1, characterized in that the fuel burner system is a combination gaseous and liquid fuel burner system (12 and 14).
Claim 6
Dependent Claim
23 words
A burner system according to claim 1, characterized in that the fraction F is in the range of 60 to 75% of T,
Claim 7
Dependent Claim
18 words
A burner system according to claim 1, characterized in that the fraction F is approximately 70% of T.
Claim 8
Dependent Claim
89 words
A burner system according to claim 1, characterized in that the means for simultaneously controlling the primary plus secondary and tertiary combustion air flow rates in the ratio F/(1-F), comprise a first air control means (38, 40 and 42) for controlling primary plus secondary air (60 and 62), a second air control means (38, 40 and 44) for controlling tertiary air (50), control of primary plus secondary and tertiary air being in a fixed ratio (F/(l-F) and means being provided to control the first and second control means simultaneously.
Claim 9
Dependent Claim
131 words
A burner system according to claim 1, characterized in that the means for simultaneously controlling the primary plus secondary and tertiary combustion air flow rates in the ratio F/(l-F) comprises a wind box (36) having a fixed inner-cylindrical wall (40) and a rotatable contiguous outer cylindrical wall (38), a first plurality of symmetrically spaced circumferential openings (42) for the passage of primary plus secondary'air each of the openings being of selected angular width W (39) and length P (37), the openings being identical in both walls, a second plurality of symmetrically spaced circumferential openings (44) for the passage of tertiary air, each of the openings being of selected angular width W (39) and length S (35), the openings being identical in both walls and wherein the ratio of P/S - F/(l-F).
Claim 10
Dependent Claim
32 words
A burner system according to claim 1, characterized in that water atomization means (68, 70, 88 and 89) are arranged , in the vicinity of the fuel burner (64) and upstream thereof.
Claim 11
Dependent Claim
69 words
A burner system according to claim 1, characterized in that the primary combustion space (l6, 18) is within a first inner cylindrical tile wall (20), and a second outer tile wall (24) downstream of the first tile wall (20), the tertiary combustion air (50) passing outside of the second tile wall (24) to the secondary combustion space (28) downstream of the end of the second tile wall (24). -
Claim 12
Dependent Claim
45 words
A burner system according to claim 10, characterized in that the liquid fuel is fired axially inside of the inner tile wall (20) and the gaseous fuel is fired inside of an annular space (22) between the first (20) and the second (24) tile walls.
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