Study of the impacts of supplements on the specific methane production during anaerobic digestion of the West African Gamba and Guinea Grass

Abstract

Nutrient supplementation could improve the biomethane production of different biomass feedstocks during anaerobic digestion. In this study, the impact of nutrient supplementation on the anaerobic digestion of the West African Gamba and Guinea Grass for biomethane production is presented. This was undertaken in 6 separate continuous stirred tank reactors for a hydraulic residence time of 25 days under supplementation regime with trace elements (TE), cocoa pod (CP) ash-extract, and commercial cellulase from Aspergillus niger (CCA) or Trichoderma reesei ATCC 26921 (CCT). The results showed that TE inhibits the specific methane production (SMP) with about 5% lower SMP than the control. In contrast, the other supplements namely CP, CP + CCA, CCA, and CCT + TE showed about 13, 28, 18, and 12% higher SMP than the control respectively. This study is the first demonstration of the impacts of different supplements on SMP during the anaerobic digestion of the West African Gamba and Guinea grass.