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New Nano Desalinization Method

lbmouse writes "The Technology Review is reporting that researchers at the Lawrence Livermore National Laboratory have announced a way to use carbon nano-tube technology to reduce the cost of desalination of ocean water by 75 percent over current methods of reverse osmosis. From the article: 'The technology could potentially provide a solution to water shortages both in the United States, where populations are expected to soar in areas with few freshwater sources, and worldwide, where a lack of clean water is a major cause of disease.' The technology may also lead to new ways of eliminating carbon dioxide emitted from power plants."

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  1. Where does the lawn water go? by Latent+Heat · · Score: 4, Insightful
    I think the argument the lawn-waterers are making is that if they pump water out of the ground and sprinkle that water back on the lawn, most of that water will percolate back through the soil back into the ground water. Whether that argument holds up or not depends on such factors as the rate of transpiration and evaporation off the grass, whether the runoff water percolates back into the ground water reservoir or runs off somewhere else. That paper mill may be sucking the water out of the ground and then discharging it in polluted form in a stream, thus depleting the water table.

    I am hard pressed that anyone living where there is normal rainfall for growing grass (i.e. Georgia) and has a water table high enough to tap with a private well isn't simply recycling the water by pumping it from below and discharging it on the surface. In fact, ground-source heat pumps are the next big thing in saving energy resources -- some of the systems are closed loop with a coil to pipe in the ground, other systems are open loop, lifting water from a well and discharging it on the surface. The various state DNR's that issue permits for such open loop systems want you to discharge on the surface -- they certainly don't want you pumping water that you have handled directly back into the aquifer without being filtered through the ground.

    I agree that lawn watering is a serious use of resources in the desert Southwest U.S. You can be Fremen in your view of lawns on Arrakis, but to argue the same point on Caladan is stretching matters a bit far.