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Intake System For the approximately three quarters of a million gallons per minute of sea water taken into the plant, a forebay entrance 300 feet wide is used. Gratings across the entrance collect trash and debris. Mechanical raking facilities collect the trash where it is lifted out and dumped into a sluiceway for discharging to the outlet canal. Traveling screens then collect finer material from the water flow. Water is pumped to backwash the screens into a collection trough which discharges into the sluiceway. Chemical Treatment A system of spargers is used to inject chlorine directly into the concrete forebay at frequent intervals to prevent biological growths. It is estimated that about 750 1bs. per day of chlorine is required for one hour's dosage per day. Scale formation in the heated brine system is prevented by decomposing the carbonates with sulfuric acid. To minimize acid consumption, only the net makeup water is treated. Acid is injected into the pump discharge stream, and resulting pH is controlled so that alkalization is not required. 330 barrels of acid are used per day. The acidified stream discharges over baffles for agitation into an open basin where the major part of CO2 is released to atmosphere. The water flows by pressure differential into the deaerator. Evaporator The evaporator train will consist of 28 stages to obtain a high gain ratio of 13.4 pounds of product water per pound of steam used.Epson Perfection 4870 Photo, 400 dpi, 8 bit, 14,430,208 byte