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NUCLEAR DESALINATION
The United Nations estimates that the number of people without access to safe drinking water is 1.1 billion, or nearly one in six persons worldwide. One solution is to draw water from the ocean and remove its salt. In 1963 ORNL's Philip Hammond promoted the idea that fresh water can be obtained cheaply by desalting seawater using excess heat from large nuclear power plants. ORNL Director Alvin Weinberg—then a member of President Kennedy's Science Advisory Committee—described this method of providing energy and making the "desert bloom" to Atomic Energy Commission and Interior Department officials and obtained project funding for ORNL. Hammond's concept was featured at a 1964 United Nations Conference on Peaceful Uses of Atomic Energy in Geneva, was supported by President Johnson's 1965 "Water for Peace" program, and is endorsed by the International Atomic Energy Agency. ORNL researchers contributed to desalination technology in two ways. Hammond's team improved distillation technology, to separate salt from seawater more efficiently using heat from nuclear plants. The group developed enhanced heat-transfer surfaces and processes for multi-stage flash distillation and designed aluminum vertical tube evaporators that were four times more efficient than contemporary models. Kurt Kraus's team increased the efficiency of reverse osmosis (RO) and adapted it to desalination. In RO, pure water is produced by forcing salt-bearing water through a semi-permeable membrane that prevents salt passage. RO is used in almost half of today's desalination plants. The heat source for desalination is oil or gas, except for a new plant in Kalpakkam, India, which is coupled to a pair of existing reactors. At least three other nations are developing desalination reactors, suggesting that nuclear desalination may become a major fresh water source. |
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Web site provided by Oak Ridge National Laboratory's Communications and External Relations |
