COMBUSTION OF OIL PALM SOLID WASTES IN FLUIDISED BED COMBUSTOR

摘要

The palm oil industry of Malaysia is the largest in the world producing about 55% of the world production. The industry has approximately 270 mills throughout the country with processing sizes ranging from 10 tonnes/hour to 120 tonnes/hour.All mills produce solid wastes, about 50% of the fresh fruit bunches in terms of weight. The solid wastes produced are in the form of empty fruit bunches, fibres and shells. These wastes have high energy value, ranging from 14 to 18 MJ./kg. The industry is currently self-sufficient in terms of energy. Fibres and shell wastes are being used as boiler fuel to raise steam for electrical power production and process steam. However, the combustion technology currently being employed is obsolete with low efficiency and polluting.A fluidised bed combustor pilot plant is designed and constructed at Combustion Research Laboratory, Universiti Kebangsaan Malaysia. The combustor is made up of 600 mm × 900 mm rectangular bed filled with sand up to 400 mm height, static. A bank of heat transfer tube is imbedded in the bed, designed to absorb 50% of heat released by the fuel in the bed. The remaining heat is transferred in tubes placed on the wall of the freeboard area.Experimental studies were carried out in the pilot plant using palm oil solid wastes. The combustion temperatures were maintained in the range 800 - 900°C. The performance of the combustor was evaluated in terms of combustion and boiler efficiencies and flue gas emissions monitored.