Density of Briquettes Produced from Bambara Groundnut Shells and It’s Binary and Tertiary Combinations with Rice Husk and Peanut Shells

Abstract

The density of briquettes produced from bambara groundnut shells and its binary and tertiary combinations with rice husk and peanut shells was investigated for its potentials in domestic cooking. The bambara groundnut shells, rice husk and peanut shells were collected from various locations in Benue State Nigeria, where the agro products are produced in large quantities. The briquetting process and assessment of compressed and relaxed densities were conducted in the Department of Forestry laboratory of the University of Agriculture Makurdi Nigeria. The experimental design was 4 x 2 x 3 factorial in Completely Randomized Design (CRD) with 4 replicates.  There were 4 briquette types, 2 briquette shapes and 3 percentage starch binder levels. Bambara shells and its binary and tertiary combinations with Rice husk and Peanut shells were collected, dried, ground, sieved to uniform fraction of 1.17mm and used to produce donut and puck shaped briquettes at 15%, 25% and 35% of starch binder. The briquette combinations were Bambara (100:0), Bambara + Rice (50:50), Bambara + Peanut (50:50) and Bambara + Rice + Peanut (33:33:33). The results were analysed using ANOVA and LSD at p<0.05 and descriptive statistics. The compressed densities of bambara briquettes and its binary and tertiary combination with rice husk and peanut shells were significant. Bambara briquettes recorded the highest compressed density of 1.0g/cm3, while the relaxed densities of the briquettes were not significant. Bambara briquettes produced the lowest relaxed density of 0.55 g/cm³ while bambara + rice briquettes had the highest relaxed density of 0.87 g/cm³.The effect of percentage starch binder was significant on compressed density of bambara briquettes and its combinations but the relaxed density was not significant. The effect of briquette shape was significant on compressed and relaxed densities of the briquettes. Puck shaped bambara briquettes and its combinations recorded higher compressed and relaxed densities than donut shaped briquettes. Bambara briquettes showed favourable physical and combustion properties that are suitable for utilization as alternative fuel energy. Bambara shells and its binary and tertiary combinations with rice husk and peanut shells are therefore, recommended for production of briquettes as alternative fuel for domestic cooking due to the high energy composition of the briquette.

Keywords: Compressed density, Relaxed Density, Briquette type, Percentage binder, Briquette shape.