Development of a new technology--rich/lean combustion of pulverized coal
- Zhejiang Univ., Hangzhou (China); and others
In this paper, a new technology named rich/ lean coal combustion is introduced. The technology is used for the low load flame stabilization of pulverized coal without support oil and the prevention of furnace wall stagging. A specially designed two phase flow test facility was set up in Zhejiang University to develop a technology of air--coal mixture separation. The cross section of test pipe is 250 x 250mm. The maximal air flow in the tester can reach 6000 m{sup 3}/h and particles flux is up to 3-4 t/h. The pulverized coal in primary air is separated and two streams of air- coal- rich pulverized coal stream and lean pulverized coal stream are formed. Rich pulverized coal stream is guided to the high temperature area facing the flame. This 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 rich/lean combustion also lows NOx emission. The test results of new developed equipment shows that the ratio of the concentration of rich pulverized coal side to concentration of lean side is 7-12:1. Namely, if average CA is equal to 0.6, then C/A in rich side reaches about 1.1 and C/A in lean side is about o.1. The pressure drop of the separate equipment is about 3000-4000Pa. The retrofit of several utility boilers have been made. These include 200MW, 125MW, 100MW, and 50MW utility boilers and the coal types used include brown coal, bituminous coal and anthracite coal. The industrial tests showed that this technology is successful to meet the above three goals. The lowest boiler load of about 40-50% to keep coal flame steady has been obtained without supporting oil. The flow pattern in furnace is good and no slagging is formed on the wall of the retrofitted boilers. The combustion efficiency of the boiler to burn bituminous coal is unproved apparently after the retrofit of the boilers.
- Research Organization:
- Coal and Slurry Technology Association, Washington, DC (United States); USDOE Pittsburgh Energy Technology Center (PETC), PA (United States)
- OSTI ID:
- 171590
- Report Number(s):
- CONF-950313-; ON: TI96120222; TRN: 95:007972-0020
- Resource Relation:
- Conference: 20. international technical conference on coal utilization and fuels systems, Clearwater, FL (United States), 20-23 Mar 1995; Other Information: PBD: 1995; Related Information: Is Part Of Coal utilization and fuel systems: Proceedings; PB: 780 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Application of RBC burners in 220 t/h boilers in Xinhua Power Plant
Application of controllable pulverized-coal rich/lean combustion technology at the Hebi Wanhe Power Generation Co. Ltd.