Air gasification characteristics of coir pith in a circulating fluidized bed gasifier

Abstract The gasification characteristics of coir pith are studied in a circulating fluidized bed gasifier using air as the gasifying medium. The effect of various parameters such as temperature, Equivalence Ratio (ER), and Oxygen/Carbon ratio (O/C) on gas yield, gas composition, gas heating value, carbon conversion, cold gas and overall thermal efficiency is studied. The ERs employed in the study are 0.18, 0.21, 0.24 and 0.31. It has been found that temperature has an influence on the cracking reactions, as indicated by the increased yield of hydrogen. The maximum yield of hydrogen is obtained at a temperature of 1028.6 °C, and as the Equivalence Ratio (ER) increased, hydrogen yield decreased. The gas yield also increased with increase in temperature and ER. Also it has been observed that the gas heating value increases with increase in temperature and decrease in ER. Carbon conversion is found to increase with increase in temperature and increase in ER. It is found that the increase in temperature favours both the cold gas thermal and overall thermal efficiencies. Also the cold gas and overall thermal gasification efficiencies decrease with increase in Equivalence Ratio.

[1]  Kj Krzysztof Ptasinski,et al.  A review of the primary measures for tar elimination in biomass gasification processes , 2003 .

[2]  John R. Grace,et al.  Circulating fluidized beds , 1996 .

[3]  D. Świerczyński,et al.  Steam reforming of tar from a biomass gasification process over Ni/olivine catalyst using toluene as a model compound , 2007 .

[4]  A. Ghaly,et al.  Quality of gas produced from wheat straw in a dual-distributor type fluidized bed gasifier , 1992 .

[5]  Chuang-zhi Wu,et al.  Hydrogen-rich gas production from biomass air and oxygen/steam gasification in a downdraft gasifier , 2007 .

[6]  R. Saxena,et al.  Thermo-chemical routes for hydrogen rich gas from biomass: A review , 2008 .

[7]  Jukka Leppälahti,et al.  Catalytic purification of tarry fuel gas with carbonate rocks and ferrous materials , 1992 .

[8]  J. R. Kim,et al.  Biomass gasification in a circulating fluidized bed , 2004 .

[9]  K. Kadirvelu,et al.  Removal of heavy metals from industrial wastewaters by adsorption onto activated carbon prepared from an agricultural solid waste. , 2001, Bioresource technology.

[10]  Andrew Narvaez,et al.  Biomass gasification with air in an atmospheric bubbling fluidized bed. Effect of six operational variables on the quality of the produced raw gas , 1996 .

[11]  K. Khilar,et al.  Influence of mineral matter on biomass pyrolysis characteristics , 1995 .

[12]  J. Corella,et al.  Biomass Gasification with Air in a Fluidized Bed: Effect of the In-Bed Use of Dolomite under Different Operation Conditions , 1999 .

[13]  Javier Herguido,et al.  Steam gasification of lignocellulosic residues in a fluidized bed at a small pilot scale. Effect of the type of feedstock , 1992 .

[14]  J. V. Doorn,et al.  Ten residual biomass fuels for circulating fluidized-bed gasification , 2001 .

[15]  D. Y. Goswami,et al.  An experimental study of hydrogen production by gasification of biomass in the presence of a CO2 sorbent , 2007 .

[16]  Robert C. Brown,et al.  Steam reforming of tar compounds over Ni/olivine catalysts doped with CeO2 , 2007 .

[17]  A. S. Ramadhas,et al.  Power generation using coir-pith and wood derived producer gas in diesel engines , 2006 .

[18]  M. Aznar,et al.  Biomass Gasification in Fluidized Bed at Pilot Scale with Steam−Oxygen Mixtures. Product Distribution for Very Different Operating Conditions , 1997 .

[19]  A. Demirbas,et al.  Combustion characteristics of different biomass fuels , 2004 .

[20]  Kj Krzysztof Ptasinski,et al.  Pretreated olivine as tar removal catalyst for biomass gasifiers : investigation using naphthalene as model biomass tar , 2005 .

[21]  A. Cabanillas,et al.  Gasification of leached orujillo (olive oil waste) in a pilot plant circulating fluidised bed reactor. Preliminary results , 2004 .

[22]  I. Neethi Manickam,et al.  Study of Physical Properties of Coir Pith , 2006 .

[23]  A. Bridgwater.  The technical and economic feasibility of biomass gasification for power generation , 1995 .

[24]  D. Świerczyński,et al.  Hydrogen production from biomass gasification on nickel catalysts: Tests for dry reforming of methane , 2002 .

[25]  Peter McKendry,et al.  Energy production from biomass (Part 3): Gasification technologies. , 2002, Bioresource technology.

[26]  Ronaldo M. Barreto,et al.  Assessment of a small sawdust gasification unit , 2004 .

[27]  M. Aznar,et al.  Biomass gasification in atmospheric and bubbling fluidized bed: effect of the type of gasifying agent on the product distribution , 1999 .

[28]  Jamal Chaouki,et al.  Hydrodynamics of circulating fluidized bed risers: A review , 1995 .

[29]  C. M. Kinoshita,et al.  An experimental investigation of hydrogen production from biomass gasification , 1998 .

[30]  Anthony V. Bridgwater,et al.  Research in thermochemical biomass conversion. , 1988 .