Coal char temperature profile estimation using optical reflectance for a commercial-scale Sasol-Lurgi FBDB gasifier
- 作者：J.R. Bunt ; J.P. Joubert ; F.B. Wa ; ers
- 关键词：Sasol-Lurgi fixed bed dry bottom gasification ; Optical reflectance ; Temperature estimation ; “ ; Turn-out” ; sampling methodology ; Reaction zones
- 刊名：Fuel
- 出版年：2008
- 期刊代码：33_00162361
- 类别：ce
- 出版时间：October 2008
- 卷：87
- 期：13-14
- 页码：2849-2855
- 文件大小：280 K
摘要
In the Sasol-Lurgi fixed-bed dry-bottom (FBDB) gasifier the temperature in the combustion zone should not exceed the melting point of the ash-forming minerals, causing them to melt/flow and agglomerate. Sintering of ash particles is considered desirable in Sasol-Lurgi FBDB gasification, since it promotes easy gas flow, whereas clinkering creates channeling and localized “hot spots”, leading to unstable gasifier operation. Due to the counter-current mode of operation, hot ash exchanges heat with the cold incoming agent (steam and oxygen), while at the same time hot raw gas exchanges heat with cold incoming coal. This results in the ash and raw gas leaving the gasifier at relatively low temperatures compared to other types of gasifiers, which improves the thermal efficiency and lowers the steam consumption.