Water purification chemicals for emergency application

• Main Author: Chua, Wei Kian.
• Other Authors: Tay Joo Hwa
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Environmental engineering::Water treatment
• Online Access: http://hdl.handle.net/10356/44928
• Institution: Nanyang Technological University

After an occurrence of devastating natural disaster, accessibility to the disaster site becomes difficult due to the destruction of pathway, road and bridge. And clean water supply is usually not available within the first few days of the incident. Therefore, a fast, simple and effective method is required to treat water on site for the resident. The approach of this project is to use commonly available chemical for coagulation and disinfection treatment. Powder form of the chemical is preferred as it is more convenient to transport via air, land and road. The advantage of this approach is that it weighs much lighter to deliver powder chemical than bottled drinking water. Through this approach, a higher quantity of clean drinking water will be available. Through many round of literature review and experiment, aluminium sulphate is identify as the most suitable coagulant to treat high soil concentration lake water while poly aluminium chloride is the most effective coagulant to treat high algae concentration water (which will be discuss in another report). The optimum dosage of aluminium sulphate as Al2(SO4)3 is found out to be 160mg/L for low turbidity (100NTU), 130mg/L for medium turbidity (500NTU) and 100mg/L for high turbidity (1000NTU). For disinfection, the recommended dosage of calcium hypochlorite as chlorine is 7mg/L for not contaminated water and 17.5mg/L for water contaminated by wastewater (0.5%).