Burner and boiler equipped with burner

Patent metadata

Field	Value
Publication number	US-2016178196-A1
Application number	US-201414910142-A
Country	US
Kind code	A1
Filing date	Jul 3, 2014
Priority date	Aug 5, 2013
Publication date	Jun 23, 2016
Grant date	—

Abstract

A burner ( 10 ) includes a main combustion unit ( 20 ) configured to combust preliminary mixture gas obtained by mixing fuel gas and air at a first air ratio, and a plurality of flame stabilizing units ( 30 ) located to interpose the main combustion unit ( 20 ) and configured to combust preliminary mixture gas of a second air ratio that is lower than the first air ratio and achieves stable formation of flame.

First claim

1 . A burner comprising:
a main combustion unit configured to combust preliminary mixture gas obtained by mixing fuel gas and air at a first air ratio; and a plurality of flame stabilizing units located to interpose the main combustion unit and configured to combust preliminary mixture gas of a second air ratio that is lower than the first air ratio and achieves stable formation of flame.

2 - 5 . (canceled)

6 . The burner according to claim 1 , further comprising:
a first supply line configured to supply the flame stabilizing units and the main combustion unit with the preliminary mixture gas of the second air ratio; and a second supply line configured to supply the main combustion unit with air, wherein the main combustion unit and the flame stabilizing units are provided as areas where the preliminary mixture gas is combusted, and are disposed on a downstream side of the first supply line and the second supply line.

7 . The burner according to claim 6 , wherein:
the first air ratio is from 7% to 11% when converted to a concentration of exhaust gas O 2 , and the second air ratio is from 6% to 10% when converted to the concentration of exhaust gas O 2 .

8 . The burner according to claim 7 , wherein:
the main combustion unit includes a plurality of divisional main combustion units, and the flame stabilizing units are located to interpose each of the divisional main combustion units.

9 . The burner according to claim 6 , wherein:
fuel gas supplied to the main combustion unit is from 50% to 95% in volume of fuel gas supplied to the burner, and fuel gas supplied to the flame stabilizing units is from 5% to 50% in volume of the fuel gas supplied to the burner.

10 . The burner according to claim 8 , wherein
fuel gas supplied to the main combustion unit is from 50% to 95% in volume of fuel gas supplied to the burner, and fuel gas supplied to the flame stabilizing units is from 5% to 50% in volume of the fuel gas supplied to the burner.

11 . A boiler comprising:
a boiler body; a plurality of water pipes disposed in the boiler body and extending vertically; a lower header disposed below the plurality of water pipes; an upper header disposed above the plurality of water pipes; and a burner having a main combustion unit configured to combust preliminary mixture gas obtained by mixing fuel gas and air at a first air ratio that is from 7% to 11% when converted to a concentration of exhaust gas O 2 , and a plurality of flame stabilizing units configured to combust preliminary mixture gas of a second air ratio that is from 6% to 10% when converted to the concentration of exhaust gas O 2 and achieves stable formation of flame.

12 . The boiler according to claim 11 , comprising:
a first supply line configured to supply the flame stabilizing units and the main combustion unit with the preliminary mixture gas; and a second supply line configured to supply the main combustion unit with air.

13 . The boiler according to claim 12 , wherein
fuel gas supplied to the main combustion unit is from 50% to 95% in volume of fuel gas supplied to the burner, and fuel gas supplied to the flame stabilizing units is from 5% to 50% in volume of the fuel gas supplied to the burner.

Assignees

• Miura Kogyo Kk

Inventors

• Okabe Akiyoshi

Classifications

• F22B21/04

  involving a single upper drum and a single lower drum, e.g. the drums being arranged transversely · CPC title

• F23D23/00 Primary

  Assemblies of two or more burners (gas burners with provision for a retention flame F23D14/26) · CPC title

• F22B31/00

  Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements or dispositions of combustion apparatus · CPC title

• F23D14/02

  Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone · CPC title

• F23C2203/10

  using heat exchanger · CPC title