Development of an Effective Microbial Consortium for Greywater Treatment

Abstract

Greywater consists of used water from showers, baths, wash basins, washing machines and kitchen sinks and excludes black water (urine and sewage flush water). About 60-70% of the total domestic wastewater generated comprises greywater. In modern times with an exploding population and limited water resources, effective water management is a challenge for civic authorities and greywater recycling can substitute drinking water usage for purposes like toilet flush, gardening etc. Microorganisms have the potential to degrade organic and inorganic pollutants and are used for such purposes in STP’s and CETP’s globally. The present study deals with the development of a microbial consortium capable of treating kitchen sink greywater collected from institutional canteen with the objective of development of a novel and economic system for its treatment. For this purpose 13 isolates were tested for their potential of treating such water and 6 isolates were developed into a consortium referred to as Bacterial Seed (BS). The treatment process consisted of 50 mg/L BS and 1% KMnO4 with aeration. These levels were subsequently brought down to 5mg/L BS and 0.01% KMnO4. Treated water was tested for BOD and total suspended solids (TSS) reduction at ……. days and achieved 92.5% and 75% reduction in these values which met the national and international guidelines for reuse. Further bacteria were characterized and 16S rRNA sequencing for one isolate was done. The developed consortium can be implemented for large scale greywater treatment with the huge potentia for non-potable reuse within communities.