| abstract |
PROBLEM TO BE SOLVED: To provide a method and a treating agent for purifying water which can perform a stable coagulation / sedimentation treatment even during the growth of algae, and have a high turbidity effect and a reduced amount of sludge generation. SOLUTION: The method of purifying water includes adding and mixing an organic coagulant or an inorganic coagulant and an organic coagulant to raw water for water purification, and then adding and treating a polymer coagulant. The flocculant can be an anionic polymer flocculant, a nonionic polymer flocculant or a cationic polymer flocculant, and an inorganic flocculant and / or an organic flocculant is added to raw water for water purification. After mixing, a cationic polymer flocculant is added, and further, an anionic polymer flocculant or a nonionic polymer flocculant is added and treated. It is a treating agent for water purification comprising a flocculant and a polymer flocculant. |