Gasification of pine and oak trees with a dolomite in a fluidized bed reactor

Renewable woody biomass is promising for the production of fuel and chemicals by pyrolysis and gasification. Especially, current thermal processing techniques tend to generate products with a large slate of compounds such as gaseous products, bio-oil and bio-char. In Korea, pine trees and oak trees occupy over 50% in forest. To understand decomposition characteristics, thermogravimetirc analysis of pinus rigida and oriental oak were investigated using TGA. These samples were gasified in a fluidized bed reactor, and the effects of reaction temperature, residence time, and catalyst species on gas yields and selectivities were investigated over a temperature range of 800 to 900â,. With increasing the gasification temperature from 800 to 900âf, the gas yield of pinus rigida maintained 75.15∼78.41%, whereas the gas yield of oriental oak decreased from 71.05 to 58.15%. The gaseous products consisted of mostly CO, CO ₂, H ₂ and a small fraction of C ₁-C ₄ hydrocarbons. The effect of catalyst species on the product yields was studied after gasification at 860 â,f of pinus rigida and oriental oak, respectively. It is interesting to notice that using dolomite catalysts showed different behavior on product yields of pinus rigida and oriental oak samples: lower gas yield in pinus rigida and higher gas yield in oriental oak. When pinus rigida was gasified over dolomite, Co/dolomite and Ni/dolomite catalysts at 860â,f, the H ₂/CO ratios were 1.34, 1.53, and 1.57, respectively, and those values for oak tree sample were 1.02, 0.84, and 0.88, respectively.