Enhancement of methane production and wastewater treatment from algae

Abstract

In this study, the synergy between wastewater treatment and anaerobic co-digestion (AC) was evaluated. To fulfill this objective, urban wastewater and pig effluents were treated by means of microalgae and macroalgae sampled from Limay River, Neuquén-Argentina. Comparison between macroalgae, aquatic and terrestrial plants as best co-substrate in AC process was performed using BiochemicalMethane Potential (BMP)method. To understand their contributions to methane production, Biological Nutrient Removal Model N°2 (BNRM2) was used to represent dynamic data of BMP assays. Results indicate high performance of organic matter removal by algae (63.8 ± 0.5%COD) with high biomass production. BMP assays showed macroalgae as the high methane potential cosubstrate (157.2 ± 66.1 ml CH4/g VS). BNRM2 implementation showed good fit of dynamic data and reveals that the more methane produced, the higher the hydrolysis rate. In conclusion, algae could be used as a link point between wastewater depuration and anaerobic co-digestion processes.