Evaluation of Co-torrefaction Performance of Coffee Bean Ground and Risk Husk Mixture for Bio-Solid Production

Abstract

Co-torrefaction is a thermal process is used to torrefied blending biomass at 200-300˚C in an inert atmosphere to enhance its fuel properties such as increasing of heating value and carbon content and decreasing the volatile matter or oxygen content. Co-torrefaction of several biomass may be a viable solution since it not only produces biofuels but also addresses waste treatment concerns blending two or more bio waste streams independently at variable blending ratios enhances the quality of the biofuel and alleviates waste management concerns. When biomass waste is blended with other waste materials to create a better-quality solid fuel product, a synergistic effect on mass and energy yields, as well as product qualities, was seen. Co-torrefied biomass as an elemental composition equivalent to that of anthracite and bituminous coal. Different reactor types, such as fixed bed, fluidized bed, and conventional bed reactors, are used for co-torrefaction, in which different biomass blends with optimized blend ratios are combined and the torrefaction process occurs to not only increase the biochar yield and heating value, but also the capacity to adsorb carbon dioxide. Because of this, the procedure must be a viable, green, and sustainable one that does not generate any pollution. This study discusses the impact of temperature on torrefaction of rice husk (RH), coffee bean ground, and their different blending ratios. The blending ratio used in this experiment is CBG: RH (50:50) RH: CBG (75:25), RH: CBG (25:75) ratios in % , RH100%, and CBG 100%. The array of experiments for co-torrefaction is performed using a lab scale tube furnace. The fiber structure is ruptured by varying the torrefaction temperature from (200,225,250,275 and 300°C). The increase of temperature resulted in the decreases of mass yield, energy yield, and oxygen to carbon atomic ratio. In addition, the torrefaction index on a yield basis (weight loss, severity index, and torrefaction index) is enhanced at elevated temperature. The high carbon content and better fuel properties were found for CBG 100% and blending ratio of (CBG: RH (75:25)) rice husk and coffee bean ground at 300°C for 60min. The resulted data of this investigation indicate that torrefaction is an effective pretreatment process to improving rice husk and coffee bean ground fuel properties.