Collection of waste water in feed collection tank followed by clarification, dual media filtration and fine tuning in basket strainers before entering to the next phase of the treatment. In the clarifier, BOD/COD/SILICA/SUSPENDED SOLIDS are partially removed. The remaining suspended solids are removed in dual media (Sand and Anthracite) pressurized filters. Any escaped fine particles are entrapped in basket strainers which acts as a safety mechanism in case the bottom distribution system fails.
Ultrafiltration is a membrane process in which a porous membrane is used to separate or reject colloidal and particulate matter. Similar to other membrane process, Ultrafiltration is a pressure driven process. High permeability of ultrafiltration membrane and negligible osmotic effects allow the ultrafiltration process to operate at relatively low pressures. In UF, the remaining BOD/COD/SILICA/ SS/ OIL/GREASE are removed and the permeate is fed to Reverse osmosis system.
REVERSE OSMOSIS SYSTEM
The permeate from UF is fed into the system through 5 micron cartridge filters. Before entering RO skids chemical like anti scalant /HCl/ SMBS is dozed in order to conditioning any scaling, pH control and oxidizing elements present in the the UF permeate water The treated RO permeate goes to Degasser towers where the carbonic acid present in the water splits in to CO2 gas and Water. CO2 gas escapes from the top of the degasser tower and the water is collected in the Degassed Water storage Tank.
MIXED BED EXCHANGER
MB unit has both Strong Acid Cation Resin and Strong Base Anion resin mixed in a single vessel. The regeneration of these resins is carried out in simultaneous regeneration, i.e. cation by Hydrochloric Acid in countercurrent and anion by caustic in co-current. The MB bed exchanger functions as multiple cycles of cation and anion exchanges and thus polishes the water to best extent possible. This unit ensures consistent quality of DM water with a pH 7 ± 0.2.
SLUDGE HANDLING AND DISPOSAL SYSTEM.
The clarifier sludge is removed from the bottom of clarifier into the sludge sump. This sludge has around 6% consistency and is further pumped into the sludge centrifuge with the help of pumps. The dewatering polyelectrolyte is added into the sludge for enhancing the performance of centrifuge. Two centrifuges are provided for the purpose ( one working and one standby ). The centrifuges are located on first floor of chemical house. The sludge produced is dumped on ground floor directly in the trolley ( provided by others). This trolley is taken away for disposal of sludge. The centrifuge is designed for sixteen hours operation as lot of time is required for removal and setting of fresh trolleys
Two numbers solution feed V-notch vacuum eductor type chlorinators are provided for chlorination of clarified water. The operating chlorinator shall withdraw chlorine gas from dedicated working chlorine tonne container with the help of vaccum regulator mounted on tonner. Also one standby chlorine container shall be provided. The clarified water is chlorinated with the help of these tonner mounted chlorine tonner. Two ( one working and one standby ) chlorinators are provided for the purpose.
Dolomite Lime Dosing system
The lime dosing system is complete with automatic dolomite lime handling and feed system, dosing tanks, etc.Two tanks with 4 hrs retention time are provided for the same. Two dosing pumps provided are of centrifugal type and flow meter is provided for quantity measurement. The flow is controlled with the help of VFD provided for these pumps
Other Dosing Systems
All the dosing tanks are provided with level switches for low level trip i.e. pump safety. The pumps are provided with common external pressure relief valves . The chemical preparation is manual i.e. addition of chemicals is done manually. The required amount of chemicals are added to achieved required concentration.