Author(s): Amir Asyraf; Hiroaki Terasaki; Kenji Furuichi; Shunya Kato; Tomohiro Umemura; Teruyuki Fukuhara; Mika Hasegawa; Yukinori Kusaka
Linked Author(s):
Keywords: Water-related disasters; Triangular solar still; Distillation; Distilled water; Water quality
Abstract: Water-related disasters can pollute existing clean water supplies with unwanted substances, which result in water scarcity. Even though there are technologies that can provide water-relief during disaster periods, these solutions can be expensive, require electricity, or may be unable to treat seawater (salt water). Hence, we have developed a Triangular Solar Still (TrSS) to produce distilled water. To ensure that the resulting distilled water was potable, we measured seawater ion content, iron content, nitrate content, total organic carbon, odor, and total and fecal coliforms, which are important parameters during disaster periods. In the experiment using seawater, seawater was distilled, and the output water had a mineral composition of 0.001 mg/L Cl-, 1.3 mg/L Na+, 0.1 mg/L Mg2+, 0.4 mg/L SO4 2-, 1.4 mg/L Ca2+, and 0.7 mg/L K+, which is similar to the ion concentrations found in distilled water. After distillation, iron was not detectable, while nitrate was reduced to 3.7 mg/L. The variables measured in the distilled water produced from seawater and water high in iron and nitrate were lower than water quality guidelines determined by the WHO or the Japan Ministry of Health, Labour and Welfare. Water needed to be distilled at least three times to reduce the total organic carbon level below the Japanese guideline of 3.0 mg/L for drinking water and to eliminate the vinyl odor from the cover film. In addition, the TrSS sterilized total and fecal coliforms with solar ultraviolet radiation. The results show that a TrSS can produce potable, distilled water during water-related disasters.
Year: 2020