Optimizing photoperiods for enhanced microalgae-based phycoremediation of food wastewater in Malaysia

Abstract

Food processing wastewater poses significant environmental challenges due to high pollutant levels, necessitating effective treatment methods. While Chlorella vulgaris has shown promise in wastewater treatment, the optimal light/dark photoperiod regimes for maximizing biomass growth, nutrient removal efficiency, and COD reduction remain underexplored. This study evaluates the effects of 12H:12H light/dark and 24H light photoperiods on the performance of C.vulgaris in treating food processing wastewater. The 12H:12H photoperiod achieved 73% COD removal with a biomass yield of 0.44 g/L, while the 24H light achieved 75% COD removal with a biomass yield of 1.02 g/L. Both photoperiods fully removed ammonia by day 12. Although the 24H light period increased biomass production, it is energy-intensive, whereas the 12H:12H photoperiod is more energy-efficient but requires further evaluation. These findings highlight the importance of optimizing photoperiod regimes to enhance the efficacy of microalgae-based wastewater treatment. This research supports sustainable wastewater management in the food industry and aims to meet regulatory standards through tailored photoperiod strategies.