Village school students 'closed rainwater treatment system'

From the fact that many rural areas still use rainwater for living, two 11th grade students of An Lac Thon High School (Ke Sach, Soc Trang) have researched and created "Water treatment system." closed rain " is rated as satisfactory.

The two authors are Nguyen Ngoc Thao Quynh and Le Vo Hoang Yen. Quynh said: "Currently, many places people store and use rainwater to eat and drink daily. Because of their habits and lack of knowledge about clean water, they use rainwater to eat and drink directly, not processed ".

Moreover, people in rural areas still face difficulties, sources of hygienic drinking water have very high prices. From that fact, the group built a closed rainwater treatment system with steps: Handling the odor and color of rainwater through gravel and activated carbon; Osmosis, reverse filtration and microbial treatment with ozone, or SODIS method using energy to treat microorganisms.

To get clean rainwater, they use 2 filtration systems. Rainwater is pre-filtered with cloth to remove large dust, impurities (envelopes, leaves, etc.) from rainwater collection systems (roofs, gutters, etc.). It is then contained in a filter tank containing activated carbon. Rainwater from the reservoir through the activated carbon system will eliminate odor and color. Water from the reservoir into the first filter system has the desired control valve.

Thao Quynh (right) and Hoang Yen next to the model "Closed rainwater treatment system".(Photo: Xuan Luong).

In the first filtration system, rainwater from the reservoir will pass through the gravel system and activated carbon into the first filter tank by gravity. Because in this tank contains Resin cation particles that absorb the anions (negative ions) in rainwater and then pass through the second filter according to osmosis and gravity rules.

Rainwater after passing through the first filter is absorbed by the anions into the second filter, which is filtered back through Resin anion particles and cations (positive ions) in the rainwater are absorbed again. Then continue through the tube system into the microorganism treatment system.

Rainwater after deodorizing, color in the storage system, through the first and second filters, will go into the microbial treatment system containing ozone machine. In areas where there is no electricity, use SODIS measures to kill microorganisms.

The test results of the Center for Quality Measurement Standards - Department of Science and Technology of Can Tho city showed that the samples of rainwater after passing through the filtration system all meet the drinking water standards of the Ministry of Health.

Mr. Nguyen Ngoc Hai, the instructor, commented: "The topic of closed rainwater treatment system implemented by the pupils is very simple, easy to do, friendly with the environment, less expensive (only about 1.6 million VND if buying an ozone machine), highly effective, can be applied to remote, mountainous, or coastal areas. " Mr. Phan Van Hung, the local people commented: "I drank the rain water filtered through your filter system, the water is very clear and the sweetness is very pleasant".