Swimming pool disinfectant

D. Nelson, Swimming Pool Disinfection with Chlorinated-s-tria nerione Products, Special Report 6862, Monsanto Co., St. Louis, Mo., revised May 1975. 

A 5—6% sodium hypochlorite solution is sold for household purposes, of which the largest use is in laundry. Solutions of 10—15% NaOCl are sold for swimming pool disinfection, institutional laundries, and industrial purposes. Solutions of various strengths are used in household and industrial and institutional (I I) cleaners, disinfectants, and mildewcides. A small amount is used in textile mills. Sodium hypochlorite is also made on site with 30—40 g/L available chlorine for pulp bleaching, but its use is decreasing in order to reduce chloroform emissions (see Chlorine oxygen acids and salts). 

Lithium hypochlorite is used in I I laundry detergents and I I dry laundry bleaches. Like sodium hypochlorite, it does not precipitate soaps and other anionic detergents. However, lithium hypochlorite is an expensive source of available chlorine and not much is used for bleaching. Its principal use is as a shocking agent for swimming pool disinfection. 

In swimming pools disinfected by bromine, bromamide and bromimide can form. These compounds have about half the disinfecting power of HOBr giving bromine an advantage compared to chlorine. Chloramide and cblorimide have 80 to 100 times less disinfecting power than HOCl. Bromides. 

Stable A/-chloro compounds are formed by reaction of hypochlorous acid and appropriate N—H compounds. For example, HOCl, formed in situ via chlorine hydrolysis, converts di- or trisodium cyanurates to dichloro- and trichloroiso-cyanuric acids, respectively (114). Chloroisocyanurates can also be prepared from isocyanuric acid or monosodium cyanurate and preformed HOCl (115—117). Hydrolysis of chloroisocyanurates provide HOCl for use in swimming pool disinfection and in bleaching appHcations. 

Several of these compounds and their derivatives are commercially and industrially important. Urea has already been mentioned on p. 311. Again, world production of chloroisocyanurates, (C1NC=0)3, in 1987 was ca. 80000 tonnes (50000 tonnes in USA alone, of which 75% went for swimming pool disinfection and most of the rest for scouring powders, household bleaches and dishwashing powder formulations). 

Oxidizing bleaches kill microbes by reacting with cell membranes and cell proteins. The most widely used is sodium hypochlorite for household and hospital uses, and calcium hypochlorite for drinking water and swimming pool disinfecting. 

DiHalo sticks Great Lakes swimming pool disinfectant... 

Canelli E. Chemical, bacteriological and toxicological properties of cyanuric acid and chlorinated isocyanurates as applied to swimming pool disinfection. Am J Public Health 1974 62 155-162. 

This encompasses all herbicides, insecticides and fungicides. Dairy cleansers for on-farm use, crop markers, insect repellents for use on humans, swimming pool disinfectants and... 

UV can also be used in water reclamation and reuse. An example is the reclamation of swimming pool water. Usually, the swimming pool water reuse process includes coagulation, filtration, clarifier, disinfection, and pH adjustment. The conventional swimming pool disinfection chemical is chlorine however, high concentrations of residual chlorine can be harmful to human health. The UV technology can be placed between the filters and chlorine disinfection unit as a pre-disinfection unit and remove pathogens. Hence, much less amount of chlorine (compared with the process without UV unit) is needed for residue disinfectant level. 

Use Active ingredient in dry bleaches, dishwashing compounds, scouring powders, detergent-sanitizers, swimming pool disinfectants, water and sewage treatment, replacement for calcium hypochlorite. 

These products have a great advantage of being transportable in concentrated, solid form, instead of in solution as is the case with liquid chlorine bleaches. They are used in household bleach formulations, as swimming pool disinfectants, commercial bleaches and scouring compounds, and in dishwashing preparations. 

Products and Uses A commonly used bleach, disinfectant, and drain cleaner. Also used for swimming pool disinfectant, laundry bleaches, water purification, and germicide. 

Precaution Oxidizer corrosive material may ignite organic materials Hazardous Decomp. Prods. Heated to decomp., emits very toxic fumes of Li20 and Cr Uses Laundry bleach swimming pool disinfection and chlorination water treatment hard surf, cleaners as sanitizing solution for food contact... 

Ag" at 10-100 ppb (ng/mL) disinfects swimming pools. One way to maintain an appropriate concentration of Ag" is to add a slightly soluble silver salt to the pool. Calculate the ppb of Ag in saturated solutions of AgCl, AgBr, and Agl. Which would be best for swimming pool disinfection ... 

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