Culture of Scenedesmus sp. LX1 in the modified effluent of a wastewater treatment plant of an electric factory by photo-membrane bioreactor

To investigate the coupled technology for advanced wastewater treatment and microalgal biomass production, a photo-membrane bioreactor was constructed. The microalga Scenedesmus sp. LX1 was cultured in the bioreactor using liquor prepared from the effluent of an electronic device factory. The algal cell growth, nitrate nitrogen removal, orthophosphate phosphorus removal were investigated. When cultured with batch operation, the average specific growth rate was about 0.09 d⁻¹, and low nitrogen (N), phosphorus (P) concentrations in the liquor were achieved. However, under continuous operation with an inflow of 60 L h⁻¹, the average specific growth rate was only 0.02 d⁻¹, and removal rates of 100% for orthophosphate P and 46% for nitrate N were achieved. With the inflow of 120 L h⁻¹, the accumulated metal ions in the bioreactor adversely affected the algal cells. The algal cells were much easier to settle, and the removal efficiency for N and P decreased.