water treatment fungicides is to prevent the harm caused by the breeding and reproduction of microorganisms in various water systems. Its main application areas include: 1. Industrial circulating cooling water system This is the most commonly used and important area of fungicides. In cooling towers, heat exchangers and other equipment, warm, oxygen-rich and inorganic salt-containing water is a hotbed for microbial growth. Biocides are used: Control of microbial slime: Bacteria and their secretions will form a viscous biofilm (slime), which will adhere to the surface of pipes and heat exchangers, seriously affecting heat exchange efficiency and increasing energy consumption. Prevent equipment corrosion: Some bacteria, such as sulfate-reducing bacteria, their metabolites will corrode metal equipment, causing pitting and even perforation. Prevent algae breeding: in the cooling tower pool, wall and other light places easy to breed algae, plug the filter and water distributor. 2. Oil extraction and transportation Water injection in oil and gas fields: In secondary oil production, the water injected into the ground needs to be sterilized to prevent bacteria from multiplying in the formation, blocking oil and gas channels, and producing corrosive gases such as hydrogen sulfide (H₂ S). Fracturing fluid and drilling fluid: prevent the organic matter therein from spoiling and deterioration, and keep its performance stable. 3. Municipal and industrial wastewater treatment In the sewage treatment process, it is used to control the expansion of foam and filamentous bacteria in the aeration tank, secondary sedimentation tank and other links. Disinfect the treated reuse water to ensure the safety of the quality of the reuse water. 4. Paper industry Prevent microorganisms in pulp and white water systems from degrading fibers and producing putrefaction, resulting in holes or broken ends of the paper. 5. Swimming pool and landscape water body Used for disinfection, killing pathogens and algae in the water, to ensure human health and water beauty.