Calculated values showed that energy needs of the digester
would only be covered when considering the co-digestion process
at an HRT of 15 d with the best scenario possible, the one with the
lowest temperature difference and using the total energy contained
in the biogas to produce heat in a boiler. These results highlighted
the relevance of the OLR applied to digestion systems for
attaining self-sufficient energy processes. On the other hand, following
the same tendency of semi-continuous experiments, calculated
biogas and energy productions would be markedly higher for
co-digestion reactor (R2) regardless of HRT, while energy needs of
the digester would be the same for both reactors