Proximate and Ultimate Analyses of Biocoal Briquettes of Nigerian’s Ogboyaga and Okaba Sub-bituminous Coal

Abstract

Proximate and Ultimate analyses of biocoal briquettes were undertaken with the aim of presenting the analytical results and ascertaining the optimum biomass composition for use as composite domestic fuel. Coal samples from 2 coal mines of Ogboyaga and Okaba in Kogi state of Nigeria were collected. The samples were pulverized and blended with sawdust at various mixing proportions of 0:100, 10:90, 20:80, 30:70, 40:60, 50:50 and 100:0 sawdust: Coal. Cassava starch was used as binding agent while calcium hydroxide was used as a desulphurizer for the briquettes. Briquettes of various blends were produced. Proximate and ultimate analyses were carried out to ascertain the elemental composition of the raw materials and the biocoal briquettes. Experimental tests, which involved the determination of calorific value was also determined. This study revealed that biocoal briquettes from Okaba and Ogboyaga coal mines are suitable for the production of environmentally solid fuel that can be used for domestic heat applications. It showed further that all the 50/50% biocoal briquettes of the two coal samples are good as fuel. All the 50/50% biocoal briquettes compositions have better characteristics than other blends while Ogboyaga, OG90/10 biocoal briquette exhibits the best quality with the highest calorific value of 29.55 MJ/kg.