Torrefaction of Ontario Biomass for Energy Applications

Abstract

Abstract. In order to achieve energy sustainability, processed biomass can be a primary source of fuels for electrical or thermal power plants. Torrefaction is a mild form of pyrolysis at temperature ranging from 200a´¼C to 300a´¼C in minimum oxygen environment for a reasonable residence time, which improves the fuel characteristics of biomass. These improvements include hydrophobicity, low moisture contents, grindability, more stable against chemical oxidation and microbial degradation, as well as increase carbon content and heating value. This study compares the fuel characteristics of raw and torrefied biomass feedstocks from Ontario. Torrefaction occurred in a locally designed and fabricated tubular continuous reactor with an inert environment by supplying Nitrogen gas throughout the experiment. Herbaceous/agricultural biomass undergoes a more rapid mass loss compared to woody biomass during torrefaction. Carbon contents increase from 10-20% with an increase in torrefaction temperature, whereas the oxygen decreases by 10-20% with an increase in temperature. Heating value of the torrefied biomass was 10-35% higher than the raw biomass. It was observed that all torrefied products displayed hydrophobic characteristics and remained unaffected from the biodegradation when immersed in water after torrefaction. The characteristics of torrefied biomass show great potential for the sustainable energy applications.