Laserfiche WebLink
<br />, <br />J <br /> <br />Th~ prngressive heating is accomplished by piping the incoming sea <br />water through the flash chambers, starting at the low temperature end. In <br />each chamber, the flashed vapor condenses as it gives up its heat to the <br />sea water. The condensed vapor is the product water of the plant. <br /> <br />r <br /> <br />We know the conversion of sea water to fresh in great quantities will <br />require the expenditure of a staggering amount of energy -- either as thermal <br />energy for distillation or mechanical energy for pumping. The energy require- <br />ments are so large, indeed, that for some areas, atomic power may provide the <br />best answer. <br /> <br />The Fluor Corporation of Whittier, California, has completed a prelimi- <br />nary design study of an optimum nuclear reactor-saline water evaporator <br />,process. The objective of this project was to make an engineering design <br />study of a multi-million gallons per day sea water conversion plant employ- <br />ing a multi-stage flash evaporator and a light water-moderated and cooled <br />nuclear steam generator. According to the Fluor study, the cost of potable <br />water produced from sea water in a fifty-million gallon per day 52 stage <br />flash evaporator, with steam supplied by a 370 thermal megawatt pressurized <br />water nuclear steam generator and calculated to be $0.37 per million BTU's <br />in the form of steam, is estimated to be $0.42 per thousand gallons ($136.00 <br />per AF). <br /> <br />'The potential of converting inland brackish water to fresh is enormous. <br />~~~~~!:~ ::~==~ ~~ ~~~~:d~~~) ~uL p~esen~iy unusaOle, 1n many or tne aria <br />areas of the Nation and the World. Generally, brackish water will contain <br />from 2,000 to 6,000 dissolved parts of salt per million parts of water. <br />Sea water contains about 35,000 dissolved parts of salt per million parts <br />of water. ' <br /> <br />Any distillation process can be used to convert brackish water to <br />fresh, but the cost of conversion is approximately the sa~e for sea water. <br />In a distillation process, in one way or another, we boil the water and <br />condense the vapor to fresh water. In other words, we take the water out <br />of the sal t. The same amount of energy is required to boil water whether <br />if be sea or brackish. <br /> <br />One group of researchers held to the theory that it would be more <br />efficient to take the salt out of the water since the salt represents only <br />3\% of raw sea water, and in most brackish water it represents less than <br />~ of 1%. <br /> <br />Seven years ago this theory was little more than a laboratory phenom- <br />enon. Today it is a commercial reality. <br /> <br />This process, known as electrodialysis, utilizes a combination of <br />electric current and thin membranes of resin or plastic to remove the'dis- <br />solved solids from the water. <br /> <br />G- 6 <br /> <br />, <br />