INSOLUBILIZING AGENT TO NONIONIC SURFACTANT

PURPOSE:To remove nonionic surfactant simply and rapidly in the pH value range of an ordinary waste water process without using any other flocculant by adding a specific vinylphenol polymer in the treatment of waste water containing nonionic surfactant. CONSTITUTION:An agent to insolubilize nonionic surfactant which contains an aqueous solution is added to waste water containing nonionic surfactant in the treatment of said waste water. The mentioned aqueous solution consists of an aqueous solution in which one or more than two types of polymer powder of a homopolymer of vinylphenol, a homopolymer of modified vinylphenol or a copolymer of vinylphenol and/or modified vinylphenol and hydrophobic vinyl monomer. As an alternative, an agent to make the surfactant insoluble containing an aqueous solution in which said one or more than two types of vinylphenol polymer are dissolved in an aqueous alkali solution, is added to the waste water for treatment. Thus it is possible to make the nonionic surfactant insoluble easily in the pH value range of an ordinary waste water process without the joint use of any other flocculant and flocculate, remove the surfactant.