Disinfection advantages

Residual action to avoid nonregular or jagged disinfections (advantage compared to not persistent effect of UV disinfection systems)... 

In the other market areas, lead naphthenates are used on a limited basis in extreme pressure additives for lubricating oils and greases. Sodium and potassium naphthenates are used in emulsiftable oils, where they have the advantage over fatty acid soaps of having improved disinfectant properties. Catalyst uses include cobalt naphthenate as a cross-linking catalyst in adhesives (52) and manganese naphthenate as an oxidation catalyst (35). Metal naphthenates are also being used in the hydroconversion of heavy petroleum fractions (53,54) and bitumens (55). 

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. 

The uses for chlorine dioxide take advantage of the high oxidising power and broad-spectrum disinfection capabiUty. 

Chlorine dioxide yields of 95% or greater have been demonstrated. The use of chlorine as an oxidant has distinct advantages because it is usually present in municipal water treatment plants for water disinfection. 

Whereas these preparations do not possess the high bacteriostatic activity of quaternary ammonium germicides, they have the alternate advantage of being rapidly functional in acid solution. In comparative experiments of several different disinfectants, the acid—anionic killed bacteria at lower concentration than five other disinfectants. Only sodium hypochlorite and an iodine product were effective at higher dilution than the acid—anionic. By the AO AC use dilution test, the acid—anionic killed Pseudomonas aeruginosa at 225 ppm. Salmonella choleraesuis at 175 ppm, and Staphylococcus aureus at 325 ppm (172). 

Membrane processes also offer other advantages over conventional treatments. They reduce the number of unit processes in treatment systems for clarification and disinfection and increase the potential for process automation and plant compactness. Designers also thought membrane plants could be much smaller than conventional plants of the same capacity and, given their modular configuration, could be easily expanded. Additionally, these plants would produce less sludge than conventional plants because they wouldn t use such chemicals as coagulants or polymers. 

Unrestricted use of reclaimed wastewater for drinking water, however, requires careful examination. While practically a complete barrier to viruses, bacteria, and other toxic entities that must be kept out of a potable supply, RO membranes could pose serious problems should any defect develop in their separation mechanism. Given the purity and clarity of RO-treated wastewaters, however, it might be advantageous to use RO and then subject the product to well-established disinfection procedures. 

The use of UV light has been selected as disinfection agent in this case study. The advantages of this technique have been explained previously [27], Total inactivation of the E. coll present in the WWTP effluent was achieved, as can be seen in Table 4 and pressure drop in the water line was increased in 0.1 bar. 

The clinical relevance of biocide resistance of antibiotic-resistant staphylococci is, however, unclear. It has been claimed that the resistance of these organisms to cationic-type biocides confers a selective advantage, i.e. survival, when such disinfectants are employed clinically. However, the in-use concentrations are several times higher than those to which the organisms are resistant. 

The basis of ultrafiltration is that a liquor is passed through a membrane many times until the required concentration of the permeate is attained. Fouling of the membrane can be a problem and regular cleaning and disinfection of the membrane is recommended. Ultrafiltration of poly(vinyl alcohol) and starch sizes offers economic advantages over... 

Table 20.2 Alternative disinfection methods with their advantages and disadvantages...

Physical disinfection of drinking water is mainly carried out through photodegradation by ultraviolet radiation (UV). Because many pharmaceuticals have chromophores that absorb UV wavelength, UV irradiation can lead to some transformation. Comparing to chemical oxidation, such as chlorination, UV disinfection has an advantage of minimizing the formation of DBPs [73]. However, at a... 

Iodine has had limited application for disinfection of swimming pools [7] and small public water supplies [8]. One application in a reverse osmosis system has also been reported by Turby and Watkins [9]. Advantages of iodine are greater stability than chlorine, lower residual requirement, and diminished chemical reactivity toward dissolved organic compounds. 

The theoretical basis of light-induced antimicrobial treatment is described, followed by examples of its application for the cleaning and disinfection of surfaces. All available information supports the idea that PDT could offer a very efficient and cost-effective way to combat microbial contamination of foods. The advantages and pit-falls of the technique are discussed. Directions of future research needed for bringing the technology to commercial reality are identified. 

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