A technique for determining devolatilization rates of large coal particles in a fluidized bed combustor

✍ Scribed by Tabarik F. Salam; Xian Ling Shen; Bernard M. Gibbs

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 663 KB
• Volume: 67
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(88)90327-4

✦ Synopsis

A non-interference technique has been developed for measuring devolatilization rates of large coal particles in a cylindrical fluidized bed at 850°C by on-line analysis of oxygen and carbon dioxide concentrations in the flue gas. The experiments were conducted over a range of inlet oxygen concentrations (3-10 ~01%). Oxygen concentrations were analysed by a xirconia probe, and carbon dioxide concentrations were analysed by an on-line infrared gas analyser. Associated problems and suitability of the measuring technique are discussed. A bituminous coal (d= 9-16.3mm) was used and devolatilization periods > 130s were observed. The devolatilization times showed a dependence on the inlet oxygen concentration, particularly at the lower (3 ~01%) inlet oxygen concentration.

A simple calculation to demonstrate the need for considering devolatilization rates. 'coal' disnersion coetlicients. excess air levels and combustor geometry in FBC I modelling is also given.