(533c) Effect of Operating Parameters on the Fast Pyrolysis of Pakistani Maize Stalk in Bubbling Fluidized Bed Reactor

Fast pyrolysis is one of the prospective techniques employed to get energy and valuable chemicals from biomass. The yield and composition of pyrolysis products depend on the characteristics of feedstock and process operating parameters. A lab scale pyrolysis system consists of bubbling fluidized bed reactor (capacity 2kg/hr) is being designed. Effect of particle size and operating temperature on the fast pyrolysis of Pakistani maize stalk has been investigated. Experimentation was done with the temperature range of 400-600°C and particle size of 0.5-3 mm (SMD). Both parameters are found to have significant effect on the yield and characteristics of bio oil produced under the bubbling fluidized bed conditions. Bio oil yield increased with the increase of temperature followed by a decreasing trend. Maximum yield (42 %) of bio oil was obtained at 500°C with particle size of 0.5-1mm. High temperatures resulted in high ratios of char and gas. Bio oil is being characterized for various properties such as water content, pH, calorific value, acid no., density and viscosity along with Gas Chromatography/Mass Spectroscopy (GC-MS) analysis. GC-MS analysis of bio oil identified the large number of compounds including butanal, 2,3-Butanedione, Benzene, 1-Butanol, Acetic Acid, 3-Pentanone, Acetol, Toluene, 2-Butenal, 2-methyl-methyl pyruvate, Propanoic acid, Ethylbenzene, p-Xylene, Cyclopentanone, 2-methyl- o-xylene, 2-Butanone, 4-hydroxy-Furfural, 2-Furanmethanol, Benzene, 1,2,3-trimethyl-1-Heptanol, Benzaldehyde, 4-methyl-phenol, guaiacol, o-cresol, Naphthalene, Phenol, 2-methoxy-4-methyl-phenol, 2,4-dimethyl-phenol, 4-ethyl-naphthalene, 2-methyl-2-Furancarboxaldehyde, 5-(hydroxymethyl)-syringol, Vanillin, Ethanone,1-(4-hydroxy-3-methoxyphenyl), 3',5'-Dimethoxyacetophenone, 2-Propanone, 1-(4-hydroxy-3-methoxyphenyl), 4-Hydroxy-2-methylacetophenone, 4-Hydroxy-3-methylacetophenone, Levoglucosan, syringaldehyde, Ethanone, 1-(4-hydroxy-3,5-dimethoxyphenyl).  Gas Chromatography analysis of non-condensable gases produced from the fast pyrolysis process is also being done and discussed.