Resource Recovery from Wastewater and Biodiesel Production using Microalgae

Abstract

Excessive utilization of fossil fuels to meet ever-growing population demands threatens the global environment and societal sustainability. In this perspective, microalgae have emerged as a potential alternative. One of the main objectives is to address the challenge of using fresh water to treat wastewater. The problem could be addressed by mixing it with another wastewater with high COD and low light absorption. The results demonstrate that a maximum biomass yield of 2.83±0.04 g L -1 was achieved in 75% textile wastewater diluted with 25% Juice wastewater. To further assess the feasibility of process microalgae cultivated at a pilot scale. The results show that 1.7g L-1 of algae biomass was produced. To convert microalgae/waste resources into biodiesel, a new microbubble mediated mass transfer technique was developed. The results show that higher conversion of 89.90 % in 30 min. To further increase the efficiency, a new heterogeneous catalyst ([HMIM][HSO4]/Bio-MOF) has been synthesized and integrated with microbubble technology achieving a higher conversion of 92 ±4% in 30 min. To further prove the effectiveness of this process, biodiesel production was carried out at an intermediate scale achieving a conversion of 99.45% in 60 min. This work successfully demonstrated the potential of microalgae to treat wastewater without diluting it with fresh water and convert microalgae/waste into biodiesel using microbubble-mediated mass transfer technology. The developed wastewater treatment and biodiesel production methods were successfully investigated on both lab and pilot scales.