Pretreatment of brewery effluent to cultivate Spirulina sp. for nutrients removal and biomass production

Abstract

Due to the low concentration of nitrate and high contents of organics, brewery effluent was not suitable for the cultivation of Spirulina sp. This work changed the nutrient profile of brewery effluent effectively by dilution, addition of nitrate, and anaerobic digestion. The result showed that the optimum dilution rate and NaNO3 addition for brewery effluent were 20% and 0.5 g/L, respectively. Spirulina sp. grown in pretreated brewery effluent produced 1.562 mg/L biomass and reduced concentrations of nutrients to reach the permissible dischargeable limits. In addition, Spirulina sp. grown in pretreated brewery effluent had much higher protein content and oil content. So the appropriate treatment converted brewery effluent into a nutrient balanced medium for algae cultivation and alleviated the potential environmental problems. Pretreatment procedure developed in this work is an effective way to realize the sustainable utilization of brewery effluent and produce algal biomass with valuable nutrients.