Process Elements
Feed Tank: The treated effluent from the effluent treatment plant is collected in a feed tank before being fed to the downstream recycle plant.
Ultrafiltration: Feed water from the feed tank shall be filtered for removal of suspended matter to < 3.0 SDI. This is also used to reduce organics and COD. Ultrafiltration membranes were supplied by QUA.
UF Backwash Recovery: The backwash waste produced in the UF system is treated in an inline lamella system in order to maximize recovery of the system by avoiding any waste disposal from the UF system. Clear water from the lamella is taken back to the feed tank for further recovery.
RO Block: The above water is then preconditioned and passed through cartridge filters, which act as a safeguard against media breakthrough from the preceding units, followed by the reverse osmosis equipment using RO membranes supplied by Dow. This system operates at very high efficiency in terms of recovery – i.e., about 80 - 85%. It removes the dissolved impurities from the stream and produces a permeate stream of lower TDS and a reject stream of higher TDS.
Permeate is taken to the second pass RO for improvement in quality in terms of desired organics level and conductivity requirements. This permeate is used for the main process requirement.