Nutrients uptake from anaerobically digested distillery wastewater by Spirulina sp under xenon lamp illumination

Distillery wastewater is treated widely by anaerobic digestion. The anaerobically digested distillery wastewater (ADDW) still poses high concentration of pollutants which requires further treatment. In this study, the possibilities of the effect of Spirulina sp. biomass (ranging from 1 to 5 g/L) value on the treatment of ADDW was carried out under xenon lamp illumination of 10,000 +/- 200 lx with the photo period of 16:8. The reduction of chemical oxygen demand (COD) up to 15-23%, total carbon (TC) up to 18-31%, total inorganic carbon (TIC) up to 31-51% and total organic carbon (TOC) up to 1-8% were observed for the algae concentration ranging from 1 to 5 g/L over a period of 5 days. Ion chromatography analysis was carried out to analyze the concentration of inorganic compounds in the wastewater before and after the treatment. The reduction of carbonate up to 32-56%, ammonium 48-72%, phosphate 18-100%, chloride 1-8%, potassium 2-7%, magnesium 10-23% and sodium 1-9% were observed in the wastewater after treating with algal biomass ranging from 1 to 5 g/L. It was inferred from the analysis that the Spirulina sp. utilized the inorganic compounds from the wastewater as its nutrients and thus resulted in the substantial removal of pollutants from the wastewater. However, it requires further assessment for the sustainability of the algae on the wastewater. The calorific value of dry algae biomass was found as 12 MJ/kg which might be utilized for the production of biofuel.