ABSTRACT
Anaerobic digestion (AD) is one form of the naturally occurring processes of decomposition and decay, by which organic matter is broken down to its simpler chemical constituents. Methanogenic bacteria, together with extreme halophilic and thermoacidophilic bacteria, make up a group of micro-organisms which forms the distinct biological kingdom Archaebacteria. To produce the required thermodynamic conditions within the digester favourable to the conversion of higher volatile fatty acids and alcohols to acetate, a low hydrogen partial pressure must be maintained. The biowaste needs to be allowed to remain in the digester until the required level of treatment has been achieved. The actual biowaste loading in the digester is of considerable importance to both that systems efficiency in its own terms, as well as to the effectiveness of AD as a means of material stabilisation. The inherent variability of the organic fraction of Search Results municipal solid waste (MSW) makes toxicity prediction a much less simple issue.
