IIT-H researchers to develop algae, bacteria based STPs

HYDERABAD: With the aim of bettering the efficiency and effectiveness of Sewage Treatment Plants (STPs), researchers from the Indian Institute of Technology-Hyderabad (IIT-H) are working towards developing an algae and bacteria-based hybrid STP. According to a media release by the IIT-H, the STP will be cost-effective and also produce biofuel as a byproduct. The system will primarily help gated communities, apartments and commercial complexes like small markets and malls that, according to Indian environmental laws, must arrange for facilities to treat sewage generated by them on a daily basis. The media release further stated that the STP will be more energy-efficient than present-day STPs. Moreover, present-day STPs generate a lot of sludge, while the algae-bacterial system will produce comparatively lesser amount of sludge. The microalgae to be used in this system survives through photosynthesis and releases oxygen, which will be used by the aerobic bacteria to break down organic waste present in the sewage. As the bacteria breaks down the organic waste, CO₂ is released, which in turn will be assimilated by the microalgae for photosynthesis. The microalgae will also consume nitrogen and phosphorus, resulting in improved quality of water released post the treatment process. 

Further, the microalgae can also be used to generate biodiesel and other value-added products, said Dr Debraj Bhattacharyya, Associate Professor, Department of Civil Engineering, IIT-H, who heads the team of researchers working on the hybrid system.