Influence of the Use of Co-Substrates on the Anaerobic CoDigestion of Municipal Solid Waste, Cocoa Industry Waste and Bottled Beverage Industry Waste

Abstract

Colombia generates large quantities of organic waste that are not used or deposited in the correct way, therefore this project seeks to optimize the organic load of these residues using anaerobic co-digestion which is a biological process that allows the recovery and the biochemical potential of methane (BPM) from waste; thus, generating adequate treatment for the control of environmental pollution. In this project, three residues were evaluated: Municipal solid waste (MSW), cocoa industry waste (CIW) and bottled beverage industry waste (BBIW). To these residues, a physical-chemical characterization was realized prior the BMP test, which was determined: values of solid volatile, total solids, organic matter and nitrogen Kjeldahl. With the characterization obtained the mixtures were prepared in which the carbon nitrogen (C/N) ratio was varied in three levels: 25, 35 and 45, the number of grams of volatile solids (gVs) was also varied in three levels: 0.5, 1.25 and 2. Likewise, the co-substrate was varied in two: sewage sludge and pig manure. Where it was found that mixtures having a C/N of 35, grams of volatile solids of 0.5 and using as co-substrate the pig manure, generate a greater production of methane. The anaerobic co-digestion technique allows the efficient development of the process due to the synergistic behavior of the co-substrates used, which compensate for the shortcomings that each presents when performing the process separately. It is also important to mention that the mixtures that have cocoa industry waste and bottled beverage industry waste increase the biochemical potential of methane.