The application study of rich/lean stability combustion technology of pulverized coal

Conference · Tue Jul 01 04:00:00 EDT 1997

OSTI ID:490287

Zhou, Junhu; Yao, Qiang; Cao, Xinyu ^[1]

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1. Zhejiang Univ., Hangzhou (China)

Owing to the increase of difference between peak load and valley load of electrical network, many boiler must often operate at low load. Many power plants require that boiler can operate steadily at low load without support oil to improve the economy and the safety of power plant. To meet these requirements a stability combustion technology named rich/lean combustion of pulverized coal is developed by ITPE of Zhejiang University. The pulverized coal in primary air is separated into two streams of air-coal flow, one is the rich pulverized coal stream and other is the lean pulverized coal stream. The rich pulverized coal stream is guided to the high temperature area facing the name which contributes to ignition and flame stability of pulverized coal. The lean pulverized coal stream is guided to low temperature area located behind the flame and forms a air film near furnace wall that benefits to reduce the slagging on the wall. The combustion technology is used for the low load flame stabilization of pulverized coal without support oil and prevention of furnace wall stagging and low NO{sub x} emission. In this paper, a large gas-solid phase flow test facility was built to test separate efficiency of a specially designed guiding-separate equipment. The study has been done on retrofitting the tangentially coal-fired boiler, which total steam capacity is 65 t/h and the coal type used is bituminous coal, in No. 4 Power Plant of Qiqihar Paper Mill by using the stability combustion technology. The industrial test shows that the lowest load without support oil is about 45%, the pulverized coal in the furnace combusts steady. No stagging was found on the wall of the boiler retrofitted. The boiler efficiency of the boiler to burn bituminous coal is improved apparently after the retrofit, which boiler efficiency increases from 82% to 88%. It can save about 500 ton/year support oil.

• OSTI ID: 490287
• Report Number(s): CONF-970310--
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
AIR FLOW
AIR POLLUTION
BITUMINOUS COAL
COMBUSTION
FOSSIL-FUEL POWER PLANTS
PULVERIZED FUELS
RETROFITTING