Abstract
Large scale utilization of microalgae to produce biodiesel will boost large amounts of fertilizer and water consumption in upstream stage and needs excessive energy in the downstream process. To overcome these issues, the integrated energy plantation has been introduced as a suitable cultivation system, including the possibility to utilize its effluent. As a free and rich nutrient source for microalgae growth, POME was carefully evaluated in order to find out more energy return in upstream stage. In the downstream stage model, a wet lipid process pathway was chosen as the current best available method. Consequently, reducing energy consumption for the biodiesel production cycle was achieved and the energy profit ratio reached up to 2.6. Energy demand was lessened by a combination of outputs from one system, and served as inputs to another, from the integration of POME treatment, biomass power plant, biogas production, microalgae cultivation, and co-products utilization. Therefore, the energy and material balances could significantly outperform those from the single system.