Bio4gas : evaluation and analysis of wastewater treatment facilities in the scope of biogas production maximization and energy production optimization

摘要

The present work presents some of the results of five reports developed in the scope of optimization feasibility studies carried out at 6 small- and medium-sized wastewater treatment plants (WWTP) in Portugal. These 6 WWTP are operated by five companies that belong to the Águas de Portugal holding. The objective of the studies was twofold: toassess to which extent the production of biogas could be increased by means ofoperational modifications and/or by the implementation of co-digestion regimes; and alsoto simulate different scenarios for feed-in tariff of electricity taking in account energyprices calculated based upon the DL n.º 225/2007 of 11th May. In this way, several codigestionscenarios were defined based upon standard available organic residues. Theresults obtained showed that the implementation of co-digestion regimes represent asignificative potential to increase the production of biogas, in some cases, over 600%.Even though, it was concluded that in some cases the costs of introducing new regimesof energy management were not supported by the increase of energy production, so ascale factor is associated to the revenues. This study contributed to the establishment ofspecific needs in terms of information management (digester operation, energyproduction/consumption, strategy for optimisation).