Abstract

This study focuses on the production of biogas from slaughter house waste to generate optimal methane yield which has high calorific value under optimum temperature, pH and substrate proportion (blood, manure and undigested food material). In this study, two different kinds of experiment were done. The first experiment was carried out to determine the pH, total solid, volatile solid and ash content of each type of waste fermented independently at optimal temperature (35°C) and pH 7.  The second experiment was done by mixing three types of wastes based on crossed D-optimal design expert software, a well-accepted statistical technique used to design and optimize the experimental process. It involves choosing the optimal experimental design and estimating the effect of the several variables which have 42 runs at different proportions of the substrates. After the experiment, the following parameters: methane content and volume of biogas, pH, temperature, total solid, volatile solids, and ash content of each type of waste were determined. From individual type of 0.351 sample waste (blood, manure and undigested content), maximum biogas production and methane composition obtained were 01, 71, 41 and 0%, 66% and 54%, respectively. From the 42 runs experimental result, the best optimal methane composition and biogas produced were 79.26% and 0.381 l/g, respectively. Optimal conditions included 20% blood, 20% manure, and 60% undigested content substrate at pH 7.88 and t 32.49°C temperature.

Key words: Digester, biogas, methane, anaerobic digestion, abattoirs.