| abstract |
An object of the present invention is to provide a method for killing microorganisms in an aqueous system in which reducing substances such as sulfite ions and thiosulfate ions are present. A water system containing a reducing substance, particularly a water system in a reducing atmosphere containing 5 to 200 mg / L of sulfite ion and / or thiosulfate ion in terms of sulfite ion, is treated with phosphoric acid and 1-hydroxyl. In the presence of a phosphorus compound such as ethylidene-1,1-diphosphonic acid, the compound is selected from the group consisting of an organic halogen compound, an organic nitrogen sulfur compound, a compound generating chlorous acid or bromite in water, and salts thereof. Add at least one of the microbicides. [Selection diagram] None |