Reduction of Nitrogen and Phosphorus Content in Piggery Water with Algal Culture

Animal waste causes environmental problems like eutrophication of ground and water. The objective of this study was to fix the total nitrogen (TN) and total phosphorus (TP) in swine waste into biomass by investigating the performance of sole and mixed algae species culture with fast growth algae Scenedesmus obliquus and wild algae Chlorella sp. Wastewater concentrations varied from 25 to 100% and initial pH varied from 6 to 9 were conducted. The results indicated that the initial wastewater concentration and pH are crucial to biomass growth and the removing rate of TN and TP. It was found out that the maximum biomass growth rate of 73 mg/l/d was achieved with mixed species culture in 75% piggery wastewater (with TN and TP of 54 and 12 mg/l) with pH 7, meanwhile, the removing rate of TN and TP reached 87.3% and 64.3% with 10 days culture, respectively.