Fluidised Bed Combustion: A Novel Technology for the Combustion of Low Grade Fuels

Abstract

Large quantities of wastes are produced in Kenya from industrial and agricultural activities, which could be used as source of energy. Currently only a small percentage of these wastes are utilised for energy purposes. This is attributed to the physical and chemical properties of the wastes, which make their firing in conventional furnaces difficult. A firing technology, which is increasingly becoming popular for the combustion of fuels with difficult combustion properties, is fluidised bed combustion (FBC). In the current paper, the special features of FBC have been reviewed and their advantages as compared to conventional firing systems highlighted. This has been achieved using the experiences from large-scale FBC systems as well as experimental results a semi-pilot scale fluidised bed test facility, 100 mm diameter and 9 m high. It is shown that fluidised bed furnaces have the ability to burn low quality fuels and wastes, in addition to low maintenance cost. FBC also exhibits high heat transfer coefficient. The combustion of low quality fuels can take place at high combustion efficiency and it is possible to reduce the emissions of NO_x, N₂O, CO and SO₂ to acceptable levels using standard emission reduction techniques.


Journal of Agriculture, Science and Technology Vol. 2 (1) 1999: 5670