Phytorid technology is a cost-effective water-purification system developed by the National Environmental Engineering Research Institute.
Under this, to remove the solid matter from the waste water it is treated under sedimentation process and then flows in a serpentine motion into a sub-surface chamber.
Many barriers are created in this room by means of plants, gravel and stones. In this stage the organic matter is removed. After this, the water is passed through an activated carbon filter to purify it.
Recently Tirupati Municipal Corporation has set up the country's largest plant based on this technology.