COLD PHASE STUDIES OF BIOMASS AND SAND IN A ROTATING CONE REACTOR

Abstract

Renewable biomass is now being considered as an important energy resource all over the world. Biomass is used to meet a variety of energy needs, including generating electricity, fueling vehicles and providing process heat for industrial facilities. Among all the renewable sources of energy biomass is unique as it effectively store solar energy. It is the only renewable source of carbon that can be converted into convenient solid, liquid, and gaseous fuels through different conversion processes. The thermo-chemical process includes. combustion, gasification and pyrolysis. Among these, pyrolysis is an important thermo chemical process. The pyrolysis of biomass is a thermal treatment which results in the production of char, liquid and gaseous products. Amongst the different processes which have been proposed for the energetic utilization of biomass, pyrolysis remains one of the most promising. The term `pyrolysis' is defined as the thermal treatment of biomass, in the absence of oxygen. The experimental study has been carried out to investigate the flow and mixing characteristics of biomass with solid carrier (Sand) in a Rotating Cone Reactor (RCR). The effects of operating conditions (speed of the rotating cone and particle size) on the mixing characteristics and flow behavior of biomass are discussed for a given initial amounts of particles in the RCR. The results show that the ratio of biomass and sand for correct mixing in to the reactor increased with increasing the rotational speed of the cone and speed of the cone less than 150 rpm would cause poor mixing performance. The rotating cone with high speed is helpful to increase the granular fluidity and mixing rate. The experimental set up mainly consists of a glass cone with OD 245 mm, and height of cone was 205 mm. For collecting the material from the rotating cone a stationary cone (OD of 500mm) is fixed around the glass cone. So under the centrifugal action, some particles pass the upper edge of upper rotating cone and entered the lower rotating cone at this time the mixing takes place in between biomass and sand. To collect small quantity of out coming sand and biomass mixture a hole is made (of bowl size) in the stationary cone. The bowl can be inserted and removed easily in between of experiment run. So the complete mixing condition is observed when sand and biomass ratio in reactor and out reactor is equal. The proximate and elemental analyses of biomass were determined. The biomass should be from I to 9.88% for the good mixing of biomass and sand in RCR. The mixing of biomass and sand also depends upon the rotational speed of the cone and size of the feed material.