oa Performance evaluation of algae (Chlorella vulgaris) for the treatment of textile waste water and biofuel extraction for energy conservation

In the past few decades, rapid industrialization has greatly contributed to the increase in environmental pollution and the decline in several energy resources. Greenhouse gas accumulation, emissions of particulate matter into the atmosphere and the release of untreated wastewater from different industries are serious threats to a sustainable environment. In particular, the wastewater from the textile industry is highly toxic and unable to be reused for industrial processes and irrigation. This toxic water ultimately makes its way to rivers and oceans and adversely affects the aquatic life. This paper focuses on the treatment of industrial wastewater obtained immediately after the dying process by algae growth, which leads to a significant decline in COD (chemical oxygen demand), total nitrogen/carbon, alkalinity and turbidity levels. Samples of wastewater from the textile industry were subjected to the treatment with fresh water algae (Chlorella vulgaris) and algal stains were found in heterotrophic mode. After about six days, algae were properly cultured on textile wastewater. It was found that 54% nitrogen, 24–28% alkalinity and 78–82% of COD were removed, allowing the treated wastewater to be used for other industrial processes. The cultured algae were further harvested (using centrifugation) for the extraction of biofuel that could be used as an alternative energy source for different industrial processes. This method of treating textile wastewater is not only cost-effective but also yields far better results for reducing water toxicity and providing an alternative fuel source.