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The Water Purification Disc "MadiDrop"


    From VOA Learning English, this is the Agriculture Report.

    Students at the University of Virginia have developed a new way of purifying water. They say it could bring improved water quality to millions of people in the developing world.  They called it MadiDrop. Field testing begins recently in South Africa. The laboratory in which the MadiDrop is made operates like a kitchen.

    Workers add ingredients and mix, weigh, press and bake. What the workers are making is a ceramic disc that contains silver.

    When the disc is dropped in water, silver ions are released to purify the water. Ions are atoms that have an electrical charge. Testing at the University of Virginia shows that the disc produces clean, safe water.

    Beeta Ehdaie is a doctoral candidate at UVA.

    "It's not just about making a really great technology that effectively removes or kills bacteria and pathogens.  It's about making a low cost, simple to use one, tailored to people in developing countries who don't have many resources."

    The students are experimenting with different sizes of MadiDrops to match them with different sized water containers.  Why the name "MadiDrop"?

    The word "madi" means water in Tshivenda, a language of Limpopo Province in South Africa. There, fifty women run a factory that makes water filters. The university started the factory last summer.

    The women mix sawdust and clay to make flower pot shaped filters that they use to purify drinking water. The water flows through the filters is which trap bacteria and solid particles. The factory sells the filters to local families. Manager Certinah Khashane says the work has changed the women's lives.

    "When they get money for those pots, they just buying school uniform for their children."

    But the MadiDrop is smaller and less expensive than the filters.  Over the next few months, students will test the MadiDrop in South Africa.

    Maggie Montgomery  is a water expert with the World Health Organization. Over Skype, she explained what field testing should show.

    "Do they find it convenient, does it have a certain taste they don't like to the water, what happens once it becomes exhausted?"

    If the testing is successful, the South African women will make and sell the MadiDrops. The goal is to expand such factories to other developing countries and improve millions of lives each year.

    Jim Smith is a UVA engineering professor. He leads the project.

    "Imagine a magic stone and you take this magic stone and you drop it in your water container.  It purifies the water and makes it safe to drink.  And then imagine that this magic stone only costs a few dollars. That's what a MadiDrop is." 

    Professor Smith says he has received calls from companies that want to make the MadiDrop.

    And that's the Agriculture Report from VOA Learning English. I'm Christopher Cruise.