A novel performance study of kiln using long stick wood pyrolytic conversion for charcoal production

In India, a considerable quantity of charcoal is used in urban areas for applications ranging from industrial processing to domestic cooking. In this article we describe a practical method for manufacturing high-quality charcoal from biomass that realizes yields of 48-83 % on energy basis with a reaction time of about 5 hr, depending on the moisture content of the feed. An experimental study of the conversion by pyrolysis of long-stick wood to charcoal in a partial combustion kiln was conducted to understand and upgrade the process. The present study investigates the process of partial combustion in charcoal kilns. With this concept, a 250kg capacity metal kiln was designed and constructed. For the test period of 5 hours, 250 kg of long stick wood was converted into 100 kg of charcoal. The average conversion ratio of 4:1 means that 4 kg of air-dried fuel wood is burnt to produce 1 kg of charcoal. The temperature profiles of 456-600o C inside the kiln help to understand the process of pyrolysis reactions to obtain charcoal in final form. The efficiency is more than double that of the traditional kiln process, thereby reducing emissions. In addition all gases are generated during the carbonization process with escape in to the atmosphere with the traditional production process are reused into the kiln, resulting in very low overall emissions.