Keywords: fluidisation, fluidised bed combustion, rice husk, rice straw, fluidised bed reactors, combustors, gasification, power generation, waste disposal, GHG reduction, greenhouse gases, combustion efficiency, carbon conversion efficiency, cold gas efficiency, combustion intensity
Fluidised bed combustion and gasification of rice husk and rice straw – a state of art review
Rice is cultivated in all the main regions of world. The worldwide annual rice production is 666 million tons for the year 2008. The combustion and gasification of rice husk/rice straw in fluidised bed reactors seems to be an attractive possibility of future for power generation, the solution of waste disposal problems and the reduction of greenhouse gases. In this paper, overview of fluidised bed reactors based on rice husk/rice straw and some data collected/measured from rice husk-rice straw power plant is presented. Combustion efficiency from 60% to 98%, combustion at bed temperature from to 600°C-850°C, carbon conversion efficiency up to 98% and cold gas efficiency up to 67% is reported. Gas heating value up to 6.6 MJ/m³ and 5.5 MJ/kg is reported. Combustion intensity up to 530 kg/h/m² is reported. Sox and NOx emitted from fluidised bed combustors based on rice husk and rice straw are generally very less under normal operating conditions.