ST-02: Production technology of clean biofuels from lignocellulosic biomass resources

Biofuel production technologies of BTRC are briefly described in terms of the priority projects on ethanol fermentation from woody biomass and agricultural wastes such as sugarcane and oil palm residues through non-acidic mechanochemical and/or hydrothermal pretreatments, BTL(biomass to liquids) by clean gasification, F-T (Fischer-Tropsch) synthesis followed by catalytic upgrading reactions, and the evaluation of total biomass system by simulation.

For the pretreatment technologies, the hydrothermal treatment method using hot-compressed water, the mechanochemical treatment method based on mechanical treatment such as pulverization and their combined pretreatment is optimized. We found that the on-site production method of saccharification enzymes may be most economical for the bioethanol production from lignocellulosic biomass. We have already confirmed that the milled Eucalyptus and Douglas fir treated by the culture broth containing a kind of fungus "Acremonium" are saccharified. We are now focusing on the breeding of fungus with high saccharification enzyme production capability by using the mutation methods.

BTL process consists of gasification to synthesis gas (CO/H₂), gas cleaning by tar removing, F-T synthesis from CO/H₂ and hydrocracking/isomerization of wax products to increase clean diesel fuel fraction. In gasification of woody biomass, a bench plant of fixed-bed gasifier (about 0.1 ton/day capacity) was found to be effective for BTL application in combination with gas cleaning, storage, and F-T slurry-phase catalytic reactor. For hot gas cleaning, the dry process by use of active carbon materials has been also developed.