The MBR technology is a relatively recent development in the field of biological treatment, using a membrane based process to produce clear treated wastewater with low turbidity, suitable for RO feed. Membranes are placed in the aeration tank to separate treated effluent from mixed liquor. Membranes being an absolute physical barrier ensure removal of suspended and colloidal impurities. MBR applications include retrofits of existing systems as well as installation of new systems, for both meeting the most stringent discharge norms and also for reuse. The MBR process operates at higher MLSS concentration with higher sludge retention time thus producing a low quantum of biological sludge and therefore reducing the sludge dewatering cost. In the MBR process, the liquid solids separation takes place using membranes. The product is a clear, low- turbidity effluent and no secondary clarifier is required in this process.