Tamil Nadu’s Geobiotechnology laboratory at the National College (Autonomous) has developed a technology that uses microbes and earthworms in sludge processing and management in collaboration with with the Perundurai Common Effluent Treatment Plant (PCEPT).

The newly developed process technique offers safe waste management and sustainable agriculture by changing industrial pollutants into nutritive biofertilizer or plant probiotics.
The technology includes two stages. In first phase, textile mill sludge is exposed to microbial pre-composting using novel dye decolorizing bacteria for 30 days.
The second phase includes vermistabilisation, where the pre-composed sludge is assorted with cow dung in a 1:1 ratio to enhance the suitability of the sludge as a growth medium for earthworm action and kept for aaround 60 days.
In this stage, earthworm Eudrilus eugeniae is used. This united process brings the advantages of both microbial and earthworm-mediated composting and minimizes the adverse impact of waste on environment by converting it into plant probiotics in a short time.
Field trials are going on in the Perundurai CETP site with a series of compositions of chemical sludge and cow dung.