Disinfectants, solid

Armeen 2-10 1-Decanamine, N-decyl- Didecylamine EINECS 214-312-1 Radiamine 6310. Industrial surfactant and intermediate for wide range of chemicals used as fabric softeners, household products and disinfectants. Solid mp = 42-45°. Akzo Chemie Fina Chemicals. 

Most surface waters contain varying amounts of suspended solids, including silt, clay, bacteria, and vimses and it is necessary to remove these before to distribution to the domestic or industrial consumer. Suspended soHds not only affect the acceptabiUty of the water but also interfere with disinfection. The principal treatment processes are sedimentation (qv) and filtration (qv). Sedimentation alone is rarely adequate for the clarification of turbid waters and is of htde or no value for the removal of such very fine particles as clay, bacteria, etc. Table 1 shows the effect of particle size on the sedimentation rate of a soHd having a specific gravity of 2.65 in water at 20°C. 

Sanitizers. Spa and hot-tub sanitation is dominated by chlorine- and bromine-based disinfectants. Public spas and tubs usually employ automatic feeders, eg, CI2 gas feeders, to maintain a disinfectant residual. Private or residential spas and tubs can use automatic chemical feeding or generating devices, or they can be sanitized manually with granular or liquid products. The most widely used products for private spa and tub sanitation are sodium dichloroisocyanurate and bromochlorodimethylhydantoin. Granular products are normally added before and after use, whereas solids, eg, stick-bromine, are placed in skimmers or feeders. Bromine generating systems can also be used and are based on oxidation of bromide ions (added to the water as sodium bromide) by peroxymonosulfate, chloroisocyanurates, hypochlorites, or ozone to generate the disinfectant HOBr. 

A useful property of liquids is their ability to dissolve gases, other liquids and solids. The solutions produced may be end-products, e.g. carbonated drinks, paints, disinfectants or the process itself may serve a useful function, e.g. pickling of metals, removal of pollutant gas from air by absorption (Chapter 17), leaching of a constituent from bulk solid. Clearly a solution s properties can differ significantly from the individual constituents. Solvents are covalent compounds in which molecules are much closer together than in a gas and the intermolecular forces are therefore relatively strong. When the molecules of a covalent solute are physically and chemically similar to those of a liquid solvent the intermolecular forces of each are the same and the solute and solvent will usually mix readily with each other. The quantity of solute in solvent is often expressed as a concentration, e.g. in grams/litre. 

Miscellaneous Proprietary mixtures, e.g. cleaning, disinfecting, bleaching, degreasing solids or solutions. ... 

Ohservahle Characteristics - Physical State (as shipped) Solid Color. Colorless to gray Odor Strong disinfectant. 

Some limitations are associated with UV radiation for disinfection. These include (1) The process performance is highly dependent on the efficacy of upstream devices that remove suspended solids (2) Another key factor is that the UV lamps must be kept clean in order to maintain their peak radiation output (3) A further drawback is associated with the fact that a thin layer of water (< 0.5 cm) must pass within 5 cm of the lamps. 

We only briefly mentioned alkaline stabilization, but in reality this is a variation of sludge pasteurization. The basic process uses elevated pH and temperature to produce a stabilized, disinfected product. The two alkaline stabilization systems most common in the U.S. are a lime pasteurization system and a cement kiln dust pasteurization system. The lime pasteurization product has a wet-cake consistency, while the kiln dust pasteurization has a moist solid like consistency. Both products can be transported to agricultural areas for ultimate use. Literature studies show that the kiln dust product can capture a marketable value of 6.60/Mg ( 6.00/ton) to offset hauling costs, while the lime product does not appear to be able to capture financial credits for product revenues at this point in time. The reasons for this are not entirely clear. 

In contrast, composting processes utilize a mixture of solids and yard waste under controlled environmental conditions to produce a disinfected, humus-like product. Three common composting systems are a horizontal agitated reactor, a horizontal nonagitated reactor, and an aerated static pile system (nonproprietary). Compost can be marketed as a soil conditioner in competition with such products as peat, soil, and mulch. Although a large potential market exists, significant effort is required to penetrate this market. Yard waste revenue of 6.50/m (S5/yd ) and product revenue of 2.00/m ( 1.50/yd ) appear to be reasonable market values based on various studies reported on the Web. 

Of the four halogens, iodine is the weakest oxidizing agent. Tincture of iodine, a 10% solution of I2 in alcohol, is sometimes used as an antiseptic. Hospitals most often use a product called povidone-iodine, a quite powerful iodine-containing antiseptic and disinfectant, which can be diluted with water to the desired strength. These applications of molecular iodine should not delude you into thinking that the solid is harmless. On the contrary, if I2(s) is allowed to remain in contact with your skin, it can cause painful bums that are slow to heal. 

Sodium hypochlorite is one of the best disinfectants known, capable of killing bacteria, yeasts, fungus, spores, and even viruses. Because it is an excellent disinfectant as well as a bleaching agent, it is used in many household cleaners. Sodium hypochlorite is also used to disinfect water supplies and swimming pools (although calcium hypochlorite in powder or pellet form is often used as a substitute, due to the convenience of its solid form). 

The effluent obtained after solids removal and microbiological disinfection could be reused as cooling water, cleaning water or industrial process water in many industrial uses. A final polishing step may be necessary if higher quality requirements are needed in some specific industrial uses, e.g., cooling and boiler feed-water. Membrane processes such as NF or RO eliminate inorganic ions and reduce parameters like conductivity, alkalinity or salinity, etc. 

Tests should also be done in the presenee of organic matter (e.g. albumin) and in hard water. It is important to remember when performing viable counts that care must be taken to ensure that, at the moment of sampling, the disinfection process is immediately arrested by the use of a suitable neutralizer or ensuring inactivation by dilution (Table 11.4). Membrane filtration is an alternative procedure, the principle of whieh is that treated cells are retained on the filter whilst the disinfectant forms the filtrate. After washing in situ, the membrane is transferred to the surface of a solid (agar) reeoveiy medium and the eolonies that develop on the membrane are counted. 

It is possible to also test semi-solid antibacterial preparations on the skin itself, as described for liquid disinfectants (section 3.5.1). A portion of the skin— the backs of the fingers between the joints is a useful spot— is treated with the test organism, the preparation is then applied and after a suitable interval the area is swabbed and the swab incubated in a suitable medium. Alternatively, the method employing pig skin, described in section 3.5.1, may well be adapted to the problem of testing semi-solid skin disinfectants. 

Solid disinfectants (disinfectant powders) usually consist of a disinfectant substance diluted by an inert powder. For example phenolic substances adsorbed onto kieselguhr form the basis of many disinfectant powders, while another widely used powder of respectable antiquity is hypochlorite powder. Disinfectant or antiseptic powders for use in medicine include substances such as acrifiavine, or antifungal compounds such as zinc undecenoate or salicylic acid mixed with talc. 

Solid disinfectants may be evaluated in vitro by applying them to suitable test organisms growing on solid medium. Discs may be cut from the agar and subcultured, observing the usual precautions. 

Heretofore the milieu on or in whieh the disinfectant has been required to act has been either solid or liquid now antibacterial aetion in the gas or vapour phase or in the form of aerosol (colloidal) interaction must be considered, and this presents the problem of determining the viable airborne population. 

When the water is too alkaline, swimmers experience similar physical discomfort—burning eyes and nose and itchy, dry skin. The effect on the pool, however, is different. When water is alkaline, calcium dissolved in the pool water can precipitate (fall) out of solution. A precipitate is a solid that forms from a solution due to a chemical reaction. This solid creates unsightly scales on the sides of the pool. Like water that is too acidic, alkaline water also affects the efficiency of the chlorine. More chlorine needs to be added to alkaline water to effectively disinfect the pool. Over time, a swimming pool that is not kept at a neutral pH can become very expensive to maintain. 

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