Pretreatment of Olive Pruning Debris by Torrefaction for Bioethanol Production

Scientists from the University of Florence and ENEA (Laboratory of Technology and Equipment for Bioenergy) (Italy) investigated the use of torrefaction as a pretreatment method of olive pruning debris (lignocellulosic biomass) for bioethanol production. Torrefaction is a process of heating the biomass in an oxygen-free environment between 200^oC and 300^oC. It is sometimes called, "mild pyrolysis", "wood cooking" or "roasting".

The experiments showed that torrefaction can yield materials "which can be enzymatically hydrolyzed and fermented into ethanol with yields comparable to raw biomass."  Within the range of experimental conditions studied, the best conditions were identified at 220°C, with treatment time of 60 min. However further studies are recommended.

Treatment conditions need to be determined in order to minimize loss of pentose sugars and minimize formation of products which inhibit ethanol production, The full results are published in the journal, Biomass Conversion and Refinery (URL above).

Related information on torrefaction: http://newenergyandfuel.com/http:/newenergyandfuel/com/2008/11/19/torrefaction-%E2%80%93-a-new-process-in-biomass-and-biofuels/ http://news.mongabay.com/bioenergy/2008/07/torrefaction-gives-biomass-20-energy.html