Journal of Oil Palm Research Vol. 23 (2) August 2011, p. 1060-1068 ZULKIFLI Ab Rahman * ; MENON, N. Ravi * ; KU HALIM Ku Hamid **
The use of palm biomass for energy generation has been gaining momentum in recent times on a global level. A tar-free producer gas can be obtained in a properly designed biomass gasification process. In the current study, a tar-free palm biomass gasification system by high-temperature air is proposed. This concept was demonstrated on a pilot scale fixed bed using empty fruit bunches (EFB) under autothermic conditions. The pre-treated EFB were initially pyrolysed, and the resulting char was partially gasified in the gasification zone (oxidation zone) followed by combustion of the char residue at the reduction zone (bottom of gasifier) in an oxidation atmosphere. As the quality of the producer gas was found to be dependent on the smooth flow of the fuel and the uniformity of the pyrolysis, the difficulties encountered during the experiments are also discussed. The optimum operation of the gasifier ranged between 1.71 and 2.34 Nm3 kg-1 of air-fuel ratios at values of 28.2 and 37.0 kg hr-1 of 15% moisture feed rate, which gives a producer gas with a good heating value of about 5.18 MJ Nm-3 at a volumetric flow of 92.47-101.78 Nm3 hr-1 producer gas. It was concluded that the pre-treated empty fruit bunches are easy to gasify in a downdraft gasifier to produce good quality gas for process heating and power generation with minimum polluting by-products.KEYWORDS:
* Malaysian Palm Oil Board, P. O. Box 10620,
50720 Kuala Lumpur, Malaysia.
** Faculty of Chemical Engineering,
Universiti Teknologi MARA,
40450 Shah Alam, Selangor, Malaysia.