Biodiesel production potential of wastewater treatment high rate algal pond biomass.

This study investigates the year-round production potential and quality of biodiesel from wastewater treatment high rate algal pond (WWT HRAP) biomass and how it is affected by CO 2 addition to the culture. The mean monthly pond biomass and lipid productivities varied between 2.0 ± 0.3 and 11.1 ± 2.5 g VSS/m 2 /d, and between 0.5 ± 0.1 and 2.6 ± 1.1 g/m 2 /d, respectively. The biomass fatty acid methyl esters were highly complex which led to produce low-quality biodiesel so that it cannot be used directly as a transportation fuel. Overall, 0.9 ± 0.1 g/m 2 /d (3.2 ± 0.5 ton/ha/year) low-quality biodiesel could be produced from WWT HRAP biomass which could be further increased to 1.1 ± 0.1 g/m 2 /d (4.0 ton/ha/year) by lowering culture pH to 6–7 during warm summer months. CO 2 addition, had little effect on both the biomass lipid content and profile and consequently did not change the quality of biodiesel. [ABSTRACT FROM AUTHOR]