PURIFICATION OF CIRCULATING WATER

摘要

PROBLEM TO BE SOLVED: To control the propagation of bacteria in circulating water over a long period by adding an antibacterial inorganic oxide colloidal solution in which inorganic oxide colloidal particles containing an antibacterial metal component are dispersed into circulating water or stored water. SOLUTION: An antibacterial inorganic oxide colloidal solution in which inorganic oxide colloidal particles containing an antibacterial metal component are dispersed is added into circulating water or stored water. In the antibacterial inorganic oxide colloidal solution, the average particle size of the inorganic oxide colloidal particles is preferably 3-500 nm. In the particle size distribution of the inorganic oxide colloidal particles, the percentage of a fraction whose particle size is the average particle size±30% is preferably >=50%. By the addition of the colloidal solution, the propagation of bacteria in circulating water can be controlled over a long period.