Bioremediation of Aquiculture Wastewater by Microalgae Isochrysis zhanjiangensis and Production of the Biomass Material

摘要

Aquiculture wastewater, which is rich in nitrogen and phosphorus, is a main reason for the eutrophication of the surrounding water and is always a problem for the sustainable development of aquaculture. Althoughrnany treatments have been used in the field, the expensive cost limited their wide application. Microalgea is one of the most potential biomass materials for the renewable energy. However, over expensive cost, especially the raw material cost limited its industrialization. Microalgae can utilize the N and P in the wastewater to grow, so it is feasible to remediate the wastewater by microalgae and produce the biomass energy of microalgae from the wastewater. The present paper studied the growth of Isochrysis zhanjiangensis in three aquiculture wastewaters and optimized the cultivating condition. The research showed that Isochrysis zhanjiangensis could grow in the wastewater from the culture of Cynoglossus semilaevis. Under the condition of pH7, illumination 5000 LX and original inoculation density 0.01 mg/mL, the microalgae had the best growth. Under the optimal condition, the microalgae could eliminate 78% active phosphorus, 100% ammonia nitrogen, 62.3% nitrite nitrogen and 84.7% nitrate nitrogen in the wastewater within 11 days, which suggested that it was a good method for microalgae to cultivate in aquiculture wastewater because it could not only bioremediate the wastewater but also produce the biomass material.