Researchers at the Environmental Technology Division of the CSIR-National Institute for Interdisciplinary Science and Technology (NIIST) here have developed a bio-eco engineering system for treating greywater.
NIIST is opening a model treatment unit on its campus for treating and recycling greywater from the staff quarters on June 5, in connection with the Environment Day celebrations.
The NIIST system consisted of a modular anaerobic treatment unit (microbial process) integrated into a planted filter bed (Phytoremediation unit) for treating different types of greywater, NIIST said in a statement. The anaerobic treatment unit was a patented design from NIIST. Nearly 50% of the contaminants in the greywater would be removed in the anaerobic treatment system.
Jyotiranjan S. Ray, Director, National Centre for Earth Science Studies (NCESS), will inaugurate the model treatment unit at NIIST. NIIST director C. Anandharamakrishnan will be present.
Household wastewater except for the toilet flush-out (black water) constitutes greywater. The daily release of greywater from a normal five-member family will be around 500 litres.
Unlike existing decentralised treatment systems, the NIIST technology could handle high-strength greywater also, the statement said. Depending on the reuse application of treated water and space availability, the anaerobically treated water could be either passed through the planted filter bed or through a compact aerobic microbial process unit for producing reuse quality water.
Integrating the anaerobic process unit would reduce nearly 30-40% of space requirement compared to conventional phytoremediation (planted gravel bed) systems, NIIST said. NIIST also plans to replicate this treatment system in residential areas and commercial spaces for treating greywater in a sustainable way and ensuring better sanitation conditions.
