Evaluation of Some Combustion Characteristics of Biochar produced from Coconut Husks, Corn Cobs and Palm Kernel Shells

In developing countries such as Togo, biomass and fuel wood are essentially utilized by households for cooking, mainly in rural and peri-urban area, whereas charcoal and sometimes butane gas are used in urban area. The present study aims to investigate the energy potential of some biomasses, produced in Togo, as coconut husks, corn cobs and palm kernel shells in order to reduce charcoal utilization by making them as competitive as charcoal. To achieve this aim, raw biomass samples were carbonized and some of the obtained biochar combustion characteristics such as lower calorific value, energy per unit volume associated to bulk density, ash content and ash mineral content were explored. The results showed that palm kernel shells biochar has the highest lower calorific value (25095 kj/kg), followed by corn cobs biochar (24760 kj/kg) when, with 16560 kj/kg, coconuts husks biochar has the lowest lower calorific value. On another note, with the highest bulk density of 0.670 g/cm3 palm kernel shells biochar has the highest energy per unit volume (16813.65 j/cm3), whereas with the lowest bulk density of 0.148 g/cm3, corn cobs biochar had the lowest energy per unit volume. The ash content shows that coconut husks had the highest ash content (15.2 %), followed by corn cobs biochar (10.4 %) and finally palm kernel shells biochar (6.8 %). Among the three biochars, only palm kernel shells biochar ash does not contain chloride and sulfur. In view of these results, palm kernel shells biochar seems to be the best candidate as alternative fuel in replacement of charcoal.