Development of the biological salt removal process from artificial industrial wastewater with high TDS by Spirulina maxima microalga utilizing the response surface method

Today, the use of freshwater production methods from saltwater can be a solution for the drastic reduction of freshwater resources. This study aimed to investigate the direct usability of Spirulina maxima as a new conceptual method to remove total dissolved solids (TDS) of artificial industrial wastewater (AIW). The effects of TDS levels, pH, light intensity, and light-dark duration were examined on the microalgal growth and TDS removal, and optimal conditions were obtained with the response surface method and Box-Behnken Design (RSM-BBD). According to the obtained model, effluent TDS and pH respectively have the greatest effect in reducing TDS. The calculated values of coefficient of determination (R2), adjusted R 2, and predicted R2 were 0.9508, and 0.8636, which were close to R 2 values and confirmed the proposed statistical model. Based on this, the maximum TDS removal efficiency in this study was obtained with TDS variables (2000 mg/l), (pH 9.36), lighting intensity 4010 lux and light-dark duration of 15 hours at the rate of 76%, which shows the efficiency of this It had a method in removing artificial effluents.