Disinfectant application

Seek alternatives to chlorine for water treatment and disinfecting applications. For example, sodium hypochlorite has been used both in industrial and municipal water treatment applications (Somerville, 1990). Other alternatives include calcium hypochlorite, ozone, ultraviolet radiation and heat treatment (Negron, 1994 Mizerek, 1996). 

The electrochemical generator is designed for both small (0.136-4.5 kg C102/day) and larger scale (0.5-27 kg/h range and more) chlorine dioxide production rates. The chlorine dioxide solution from this system is suitable for sanitizing and disinfection applications as well as waste water treatment. 

This technology is currently commercially available from the MIOX Corporation, an affiliate of Los Alamos Technical Associates, Inc. While the MIOX system for disinfection applications is fully commercialized, applications for environmental remediation and Resource Conservation and Recovery Act (RCRA) waste treatment are still in the early stages of development. 

The photoelectrochemical production of chlorine at nanocrystalline titanium dioxide thin film electrodes exposed to U V light has been reported [96]. In this process, the energy from photons substantially reduces the overpotential required for the chlorine evolution process and therefore less harsh conditions are required. Metal doping of the Ti02 photoelectrocatalyst was explored but found to be not beneficial for this process. In future, this kind of process could be of practical value, in particular, for water treatment and disinfection applications requiring low levels of chlorine. 

Apart from sodium hypochlorite and sodium bromide solutions, almost all other liquid biocides (or biocide intermediates) are nonoxidizer types. Most nonoxidizers are manufactured by specialist chemical companies, who sell these branded products for scores of different sanitizing or disinfection applications, of which cooling water system treatment is only one. These chemicals may be merely renamed (according to subregistration permits) or they may be blended with other biocides or inhibitors to form new and different products with accordingly modified properties. Some biocides may only be available from the primary manufacturer, often as extremely concentrated and hazardous materials. These chemicals will then usually require some form of dilution, stabilization, and quality verification before being incorporated into a service company s product line. 

The first considered disinfection application of BDD/Si electrodes and dedicated cells such as DiaCell was the treatment of swimming pool water. After the first evaluation, this new technology also proved to be of great interest in numerous other water disinfection applications with the advantage of offering a... 

For a suitable use in disinfection applications, these diamond electrodes have to be integrated in robust-dedicated modules. The compact, modular, and easy to use DiaCell concept (several configurations represented in Fig. 6.5) has been developed and is produced specifically for BDD/Si electrodes. Such concept has proven to be very efficient either in the industry or for private use and up to now hundreds of these systems have already been provided and installed on the market worldwide. 

Examples of Disinfection Applications Dedicated Systems and Field/Evaluation Results... 

Antiviral activity was established for bicyclo[n.l.O]alkylamines (691) Bifunctional ammonium salts of type 692 were claimed to be useful as disinfectants application of the bicyclo[n.l.O]alkyl ammonium group as counterion in penicillin salts has been tested, e.g. Ref. 341. A iV-cyclopropyl moiety is also part of the antibacterial agent ciprofloxacin (BAY 09867) (693) . 693 shows strong antibacterial activity especially against Enterobacteriaceae it was considerably more active than other agents tested . 

Calcium hypochlorite is a white solid that can be purchased in granular, powdered, or tablet form. The chemical is good for small water treatment plant disinfection applications. For disinfection of swimming pool water, the solid calcium hypochlorite is also frequently used. ... 

Crosslinked chloromethylated PS beads were reacted with hydantoin and imidazolidinone derivatives to produce functionalised beads which could be rendered biocidal by reaction with free chlorine or bromine. The biocidal efficacies of the N-chlorinated and, in one case, the N-brominated polymeric beads against Staphylococcus aureus or Escherichia coli 0157 H7 in aqueous suspension were determined. The N-halogenated polymeric beads were effective in aqueous disinfection application, requiring short contact times for inactivation of the two bacteria. The functionalised polymers could be tailored to the application, depending on whether rapid biocidal activity or long-term stability to loss of oxidative halogen was desired. 11 refs. (Pt.III, ibid, p.363-7)... 

The essential characteristics that an ideal antimicrobial polymer should have include 1) simply and economically synthesised, 2) stable in long-term applications and storage at the temperature of its anticipated application, 3) not soluble in water for water disinfectant applications, 4) does not decompose to release toxic products, 5) should not be toxic or harmful to people who handle it, 6) can be regenerated upon loss of activity and 7) biocidal against a broad spectrum of pathogenic microorganisms after brief contact periods. 

Although MIMS has attracted much attention because of the aforementioned advantages over traditional analytical techniques for both disinfectants and DBFs [8], its use has so far been restricted to the cognoscenti of the research field. In this chapter, we present the protocols for implementing MIMS with the intention of expanding its access to a greater community of interested users. We focus our discussion on MIMS instruments using capillary membrane introduction probes [9], which have been the choice for water disinfection applications. More comprehensive reviews of MIMS development and applications are available in the literature [1,10]. 

Chloramine, like chlorine, is an oxidizing biocide used for disinfection. Three species collectively make up chloramines, also known as combined chlorine monochloramine, NH Cl dichloramine, NHCl and nitrogen trichloride (trichloramine), NCI3. Of these, monochloramine has the highest standard reduction potential furthermore, it is less prone to impart chlorinous taste and odor to water like other forms of chloramine. As a result, monochloramine is preferred for disinfection applications. 

The use of detergents in parenteral therapy is restricted by their toxicity. However, many disinfectant applications have been found which will not be recounted here. 

Concerning disinfection applications, Legionella inactivation, in particular, is possible with tap water without additives or with water containing at least bicarbonates, wbicb is mostly tbe case. These types of solutions provide tbe advantage of low concentrations of chloride and thus chlorine. This provides fairly easy operation and low environmental impact for water disinfection. 

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