Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Technology, Agricultural Engineering, Biotechnology & Applied Microbiology, Energy & Fuels, Agriculture, Biogas, Cocoa waste, Bio-energy, Methane, Agricultural residues, BIOGAS PRODUCTION, RICE STRAW, FOOD WASTE, METHANE, DRY, BATCH, MODE, WET, Anaerobiosis, Biofuels, Biological Oxygen Demand Analysis, Biomass, Bioreactors, Renewable Energy, Biotechnology, 3001 Agricultural biotechnology, 3106 Industrial biotechnology, 3107 Microbiology

Abstract:

The aim of this work was to evaluate the bioenergy potential of cocoa residue via anaerobic digestion. Batch and fed-batch lab-scale reactors were operated under low and high solids conditions. In the batch tests, 59 ± 4% of Chemical Oxygen Demand (COD) was recovered as methane. This corresponded with an average methane yield of 174 (wet) and 193 (dry) L kg-1 volatile solids fed, whereas a series of fed-batch reactors produced 70 ± 24 (wet) and 107 ± 39 (dry) L CH4 kg-1 volatile solids fed during stable conditions. A case study was developed for canton Balao (Ecuador) based on our experimental data, operational estimates and available cocoa waste in the area. Annually, 8341 MWh could be produced, meeting 88% of the current electricity demand in Balao. This case study proves the potential for cocoa waste as a source of renewable energy in rural areas.