SIMULTANEOUS PRODUCTION OF ETHANOL AND KRAFT PULP FROM PINE (PINUS-RADIATA) USING STEAM EXPLOSION

Radiata pine chips (Pinus radiata) were pretreated by steam explosion, for the simultaneous production of ethanol and pulp. Ethanol was prod uced fr om the depolymerized hemicellulose fraction recovered after th e explosion, while kraft pulp was produced from the steam-exploded chi ps. The conditions that best balanced sugar recovery and fibre quality were the use of steam alone, at 220 degrees C and short reaction time s (e.g. <2 min). After treatment with acid, to depolymerize short-chai n oligosaccharides, the hemicellulose hydrolyzate was fermentable to e thanol by yeasts with sugar consumption above 80%. The use of steam ex plosion reduced the consumption of pulping chemicals. However fibre da mage, although minimized significantly at lower reaction times, yielde d pulps with lower physical properties than those obtained in conventi onal kraft pulping.