ASABE Technical Library - Abstract

Abstract. The demand of environmental protection has made purifying various effluents by microalgae cultivation become an effective and socio-economical method which is by means of CO₂ absorption and consolidation and N/P removal. This study examined the biomass accumulation of using different reactor shape factors and different gas-liquid ratios (4:1, 3:2, 2:3, 1:4) in each reactor to cultivate Desmodesmus sp. (EJ 8-10). Optimal cultivation conditions for biomass accumulation and N/P removal from the digested piggery farm effluents were determined periodically. The results indicated that all the maximum numbers of biomass yield of each group were observed on the 14th day except using the largest reactors which the best date showed up on the 8th day. The maximum dry cell weight was 1.424 g/L cultivated in the smallest reactor with 4:1 gas-liquid ratio. The removal efficiency of NH₄⁺-N got the best effect 98.73% under 2:3 gas-liquid ratio and the 4:1 gas-liquid ratio was also a good choice in every set. The PO₄^3--P removal rate showed similar trend as the nitrogen removal.