Design, construction and test of a moving bed carbonizer for agricultural residue utilization

Abstract

Biochar is a carbon- rich organic material that can be used as solid biofuel as well as soil improvement agent. Developing a carbonization reactor suitable for community use will be important. This work focuses on the design, construction, and test of a moving bed biochar reactor with corn cobs as a sample of agricultural residues. The carbonization reactor design was based on preliminary experimental data on biochar production yield, pyrolysis temperature, and energy conversion efficiency. Corn cobs used were about 5- 8 cm in length and with a moisture content of less than 20% . The moving bed reactor had a total volume of 280 L and a maximum capacity of about 30 kg for corn cobs per batch. From the preliminary testing, the highest temperature of the carbonization process was in a range of 500- 600°C with the burning of cooking gas as a heat source. The corn cobs biochar produced was obtained within the residence time of about 2 h. It had good quality and was suitable for community use.