8th graders make devices that turn seawater into fresh water

Two students in Thua Thien-Hue developed a device to extract seawater into fresh water.

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The project has won the third prize in the contest of creative science and technology for youth, youth and children of the province. They are Nguyen Hoang Phi Long (grade 8/1) and Ho Van Anh Kim (grade 9/1) Dien Hoa Secondary School, Phong Hoa commune, H.Phong Dien, Thua Thien-Hue.

Born in a coastal village, the source of fresh water is very scarce, both witnessed the difficulties of the villagers who had to go to buy each carton of freshwater in the drought season. When he was young, Long had to help his mother ride a kilometer to buy fresh water to use.

Through newspapers, radios, Long saw soldiers on sea police ships and fishermen have to save each drop of fresh water to use for long business trips, she was even more determined to create filter equipment. sea ​​water into fresh water.

Once on the way to school, Phi Long shared his ideas with Anh Kim. Listening to the story, Mr. Kim said: 'For a long time, he also had this thought but could not do it. Or the two of us will work together. '

Nguyen Hoang Phi Long is introducing seawater filtration equipment into his fresh water - (Photo: BNL)

After school, the two students found the materials, went online to consult, study the principles and methods of splitting seawater into fresh water. After finding a way to filter seawater into suitable fresh water, the two students had to draw the design. The brief design was taken by two children to Mr. Nguyen Van Tam's house (their physical teacher at Dien Hoa Secondary School) for advice and suggestions. Seeing that their ideas are highly feasible, they have practical meaning, so Mr. Tam enthusiastically supported them to help them complete their creative ideas.

Three teachers and students went to the city to buy materials, make use of household items, and begin to make seawater filtration equipment into fresh water. After many corrections, finally the seawater filter device into fresh water is also completed. The three teachers took each other to the sea, put the machine in the sun and poured sea water into it. After about an hour of waiting, the first freshwater droplets were successfully filtered. Three teachers and students were happy, embracing each other happily.

Equipment for filtering seawater into Long and Kim's fresh water operated by solar energy, including components: A concave spherical mirror to focus sunlight, racks, piping systems and water tanks Sea, impurities and final filter are fresh water containers after filtering. The principle of operation of the device is that when the sea water is put into a container, sunlight will shine directly onto the concave spherical surface and the reflector converges to create the heat that makes the sea water in the flask warm up and evaporate. . The volume of condensate on the inclined surface will accumulate and be collected to the pipeline leading to the freshwater reservoir. Accordingly, if you put 1m ³ of seawater into a container of 1.2 m ² in size, after 8 hours of operation, it will get over 0.95 m ³ of fresh water.

According to Mr. Tam, this model is not new but has a very high applicability. Fresh water can be provided to functional forces at sea, fishermen during long-term fishing trips or households living on islands and coastal areas lacking drinking water.

Long and Kim's solar water filtration device for fresh water has been selected to take the national exam in Hanoi.