ABSTRACT

This study was carried out to investigate the microorganisms associated with the co-digestion of cassava peel, pig dung and cow rumen fluid for the production of biogas. These wastes were collected between July and August 2018 while the experimental studies were carried out between September and October 2018. The animal wastes were used as collected without further treatment. The blending ratio was 1:1:1(10kg of each) and was initially mixed with water in the ratio of 1:2 (10kg of waste 20kg of water) and fed into a 15 liters laboratory scale anaerobic digester using improved rubber water dispensers (35cm diameter, 55cm high). The anaerobic digestion process was batch operated for 30 days under room temperature conditions. In order to achieve homogeneity of the slurry and discourage scum formation in the system, daily stirring was carried out using the inbuilt manual stirring mechanism in the digester. The physicochemical and microbial parameters of the slurry samples analyzed using prescribed equipment's and standard methods. Daily biogas production was monitored and volume of gas measured using downward displacement method. The maximum biogas production was 1.90 Ltd 1for total anaerobic count of3.61 x 106 cfu/mL and mean fungal count of 2.1 1 x 106 cfulmL observed at the 16th day of bio digestion. The results indicate the incidence of Clostridium sp; Streptococcus sp, Lactobacillus sp; Bacillus sp, Micrococcus sp, Pseudomonas sp, Enterobacter sp, Fusarium sp, Aspergillus sp and Mucor sp were isolated and identified in slurry of the digestion of a cassava peel, pig dung and cow rumen fluid.