Air gasification of palm empty fruit bunch in a fluidized bed gasifier using various bed materials Pooya Lahijani 1 , Ghasem D. Najafpour 2,* , Zainal Alimuddin Zainal 1 , Maedeh Mohammadi 2 1 School of Mechanical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia 2 Faculty of Chemical Engineering, Noushirvani University of technology, 47147 Babol, Iran ٭ Corresponding author: Fax: +98 111 321 0975, E-mail address: Najafpour@nit.ac.ir Abstract: Use of lignocellulosic biomass as an alternative, renewable and sustainable source of energy has fulfilled part of the growing demand for energy in developed countries. Amongst various technologies applied to convert biomass wastes to biofuel and bioenergy, biomass gasification has attracted considerable attention. In this work, gasification of palm empty fruit bunch as a potential lignocellulosic waste was investigated in a pilot scale air-blown fluidized bed. Silica sand and dolomite were used as bed material. The bed temperature was varied in the range of 650 to 1050 o C. The quality of the producer gas (H 2 , CO, CO 2 and CH 4 ) and gasification performance was assessed in terms of heating value, carbon conversion efficiency, dry gas yield and cold gas efficiency. It was concluded that high temperatures improved the quality of producer gas; maximum heating value of 5.3 and 5.5 MJ/Nm 3 were achieved using silica sand and dolomite. Maximum dry gas yield of 1.84 and 1.79 (Nm 3 gas/kg biomass), carbon conversion of 91 a nd 85% and cold gas efficiency of 69 a nd 65%were obtained for silica sand and dolomite, respectively. Although the quality of the produced gas was considerably improved at high temperatures, however formation of the bed agglomerates was the major concern at temperatures above 800 and 850 o C for silica sand and sawdust. Keywords: Biomass gasification, Fluidized bed, Gas producer, Palm empty fruit bunch 1. Introduction In recent years, rapid development of modern industry has greatly increased the demand for energy. Today, fossil fuels are the most common energy sources in the world. Most countries which use such conventional fuels are facing major air pollution problems as it has been estimated that the world’s oil reserves will get depleted by 2050 [1]. Besides, significant amount of pollutants including CO 2 , NO x and SO x are emitted from fossil fuels into the atmosphere. Meanwhile, the cost of fossil fuel is globally increasing [1, 2]. Considering theses issues, boosts the importance of finding and exploring alternative, renewable and sustainable energy resources. Lignocellulosic biomass is one of the potential renewable energy resources which is receiving great worldwide attentions. Malaysia as the largest producer of palm oil generates a large amount of lignocellulosic residues including palm empty fruit bunch (EFB), palm shell and mesocarp [3]. These lignocellulosic biomass feedstocks can be efficiently utilized in various thermo-chemical conversion processes to yield energy and fuels. Among various biomass conversion technologies, special attention has been paid to biomass gasification due to its high conversion efficiency [4-6]. 3269