Modification of waste water treatment using geotextiles

Removal of suspended solids (SS) is one of the unit operation involved in the treatment of wastewater. Sedimentation process is widely used for the removal of SS from wastewater. But this method also has some disadvantages such as sludge handling and low removal efficiencies. In this investigation, nonwoven geotextiles with varying hydraulic and mechanical properties were used to treat municipal wastewater. Also, the performances of different geotextiles in treating wastewater with varying influent SS concentrations, were evaluated. Geotextile retains SS on its upstream face as wastewater is passed through it. Once the geotextile is clogged, it was backwashed with tap water for reuse. Our investigations revealed that the geotextiles were able to achieve very high removal efficiencies in the range of 70-90%, irrespective of the influent SS concentrations. But with a higher range of influent SS concentration (>200mg/L). the geotextiles exhibited very short clogging time, around 5 to 10 min., which required backwashing geotextiles every 10 min. This technique may prove to be suitable for treating low strength and low flow wastewaters having SS concentrations in the range of 100to200mg/L.