Experimental investigation on non-oxidative biomass torrefaction system

Abstract

ABSTRACT Torrefaction is a promising process for the management of crop residue, biomass upgrading for subsequent application in bioenergy-based processes such as pyrolysis, briquetting, gasification, etc. The present study deals with the development of a non-oxidative torrefaction system for the production of torrefied biomass. The reactor chamber was heated using industrial burner, and its thermal performance was assessed at three different temperatures as 204, 230, and 258 °C using groundnut shell as a precursor, and the residence time the feedstock processed using heat was limited up to 10 min. The mass and energy yield of torrefied material were found to be highest at moderate temperatures 204 and 230 °C, respectively. The highest torrefied biomass conversion efficiency was recorded about 72% at 204 °C temperature. The input energy required to produce a kg of torrefied material was recorded in the range of 0.15–0.21 MJ/kg, however, net energy gain available in a kg of torrefied biomass was found in between 17.15 and 22.53 MJ/kg, respectively. The benefit–cost ratio and payback period of developed system were calculated to be about 1.23 and 6 months, respectively. The internal rate of return was estimated at around 160%.