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I ~ o , experimental work has proved that salt does have an affinity for salt., Instead of clinging to the inner ,surfaces of the boiling tubes, scale forming constituents build up on the salt crystals we have added to the sea water. As they build up, they are simply screened out of the flow path. In our LTV pilot plant we have successfully eliminated the formation of scale on the distillation equipment at much higher temperatures than heretofore possible. What does this mean in terms of dollars and cents? This process has been selected for the first demonstration plant which will be located at Freeport, Texas. We are now advertising for construction bids for this plant which has been designed to produce 1 million gallons of fresh water per day. Our engineering estimates indicate that this plant will produce fresh water from the sea for about $1 per thousand gallons. eiliile this represents a substantial reduction in conversion costs, our extrapolations indicate this process will not reach its n,aximum of economic efficiency until it reaches an operating capacity of 15-20 million gallons per day. In plants of that size we expect this process to convert sea water to fresh for less than 60 cents per thousand gallons. , This estimate is based on our standardized procedure for estimating saline water conversion costs. It includes all costs at today's prices -- ~aI1Q, CaplCa! Lnvestment, 1nterest, operat1ng costs, malncenance, taxes, insurance, and a rather severe lO-year amortization schedule. In computing conversion costs by this procedure, capital investment represents about half of the cost of the product water. Secretary Seaton selected a process known as multi-stage flash dis- tillation for the second demonstration plant. This plant will be designed to convert sea water to fresh at the rate of 1 million gallons per day. It will be located in Southern California. The Atomic Energy Commission has agreed to provide a 40,000 thermal kilowatt experimental 10l<-tempature process heat reactor as the heat source for this plant. In flash distillation, sea water is progressively heated and then introduced into a large chamber where a pressure just below the boiling point of the hot brine is maintained. \'ilien the brine enteres this chamber the reduced pressure causes part Df the liquid to immediately boil __ or flash -- into steam. The remaining brine"is passed through a series,of similar chambers (multi-stages) at progressively lower temperatures. The San Diego plant is being designed with 42 stages. In a flash plant boiling is accomplished at relatively low temperatures snd the boiling occurs on the surface of the water rather than on a metal surface thus avoiding scale. G-5 .'