Design, Heat Transfer Modeling and Analysis Of Environmentally Benign Charcoal Kiln

Charcoal making practices are empirical in nature with built-in traditional wisdom inherited from one’s ancestors. A clear scientific study of the whole process with the interventions for controlling the influencing parameters is lacking. For long-term production of charcoal, using woody biomass seems to be ideal due to the possibility of producing them in wastelands and in a short time-frame. Moreover, the traditional method takes more time to produce a very small amount and low quality of charcoal. In this, we describe a practical method for manufacturing high quality charcoal from biomass that yields nearly 35-40% with a reduced reaction time than the traditional method of charcoal production. In this eco-friendly concept, we have designed a kiln and CFD analysis which will recirculate the carbon monoxide (CO) emitted due to drying of woody biomass (350-400^oC) and further the same will be fired from an external source and it provides heat to the kiln without the help of anymore external firing. So the amount of wood burnt is reduced so that the efficiency of the kiln is increased (35-40%). Also, the time required for the process is reduced as 34 hr due to firing from four sides which leads minimum amount of unburnt inside the kiln. The temperature profiles at 450-600^oC inside the kiln help us to understand the process of pyrolysis reactions to obtain charcoal in final form.