Communicate why you would choose CL2, NaHOCL, UV for disinfection, and which applications (drinking water Vs. wastewater.

Enteric bacteria, hepatitis, and protozoan cysts are the pathogens of most concern in residential wastewater. Disinfection represents one of the most widely used methods for killing off potentially harmful microorganisms. Proper treatment of wastewater is crucial for efficient disinfection. Due to its ability to oxidize cellular debris, chlorine is popular disinfection for municipal wastewater. Different chlorine compounds, including chlorine gas, hypochlorite solutions, and various solids and liquids, can all be used as sources of chlorine. Oxidation and ultraviolet (UV) disinfection are two alternatives to traditional disinfectants [1]. Chlorine is classified as a halogen in the periodic table. Chlorine can produce relatively stable compounds, such as cooking salt (NaCl). Hydrogen chloride is just one of chlorine's many highly reactive by-products (HCl) [2]. In North America, chlorination is the norm for purifying drinkable water. Chlorine can be found in the forms of chlorine gas, sodium hypochlorite, and calcium hypochlorite[3]. Chlorine's many applications extend from industrial disinfection to household bleach. Germs like bacteria and viruses can be eliminated by chlorination due to the chemical bonds, and chlorine breaks in their molecules. Chlorination provides the most widely used and economical form of water disinfection since it kills disease-causing germs and removes them from the water supply. Liquidized chlorine gas, sodium hypochlorite solution (NaHOCL) or calcium hypochlorite pellets, and on-site chlorine plants can all be used to disinfect an environment. To ensure that the water purification parameters, such as chlorine dose and contact periods, are optimized, a continuous monitoring system will be implemented [4]. Inactivation, or killing, of dangerous bacteria, is the fundamental measure for preventing waterborne illnesses by disinfection. To maximize the effectiveness of disinfection, it is necessary to first treat wastewater with a variety of different techniques. The improved and gradual growth of technology that concurrently limits health hazards in response to a lack of access to adequate drinking water will contribute to overall socioeconomic development by minimizing the gap between rural and urban populations' ability to get clean water [5]. A wide variety of pathogens may be killed by standard UV disinfection dosages, which are also used to disinfect water for drinking (mostly bacteria and viruses)[5]. Disinfection by-products (DBPs) are formed because chlorine is not only a disinfectant but also an oxidant, helping to get remove or chemically convert some other substances. DBPs were shown to have detrimental impacts on human health, according to reports. There must be regular testing of chlorine concentrations in public water supplies. The typical allowable levels are 0.5 mg/L for whole chlorine as well as 0.1 mg/L for free chlorine. High concentrations of total dissolved solids and total suspended solids in water make chlorine disinfection impractical. Particulates in the water will bind to genetic disorder organisms, protecting them from chlorine's disinfecting effects. In addition, they may continue to flourish in water for extended periods and spread illness to humans [4]. Research has shown that decreasing carbamazepine levels by direct UV photolysis is ineffective. The term "photolysis" describes the process through which UV radiation is used to break down the chemical bonds of contaminants. While direct UV photolysis can sometimes be beneficial, it is seldom the circumstance. The use of ultraviolet (UV) light to sterilize drinking water is rapidly gaining in popularity. After bioremediation and a sand filter, UV disinfection is used in the wastewater industry for the direct reuse of recovered water. In recent years, ultraviolet (UV) treatments have been utilized to eliminate PPCPs [6]. UV treatment is becoming more widely used as a ballast water filtration system because of its low environmental impact, low operating costs, and lack of side effects. The mechanism of action is the production of photochemical interactions between biological macromolecules like nucleic acids and proteins [7]. It also has the potential to remove smells from industrial wastewater as well as to bleach fabrics. It can also be used to keep cooling towers free of algae. The hypochlorite solution is made on-site, which is a major benefit of the method. Producing hypochlorite locally results in a solution that is safe to work with and has lower operating costs than buying liquefied chlorine. The bleaching chemical sodium hypochlorite is most often used as a disinfectant. hypochlorite is Effective against a wide range of microorganisms, including viruses, bacteria, fungi, and mycobacterium, this disinfectant has a wide spectrum of activity. However, bacterial spores and prions are resistant to sodium hypochlorite and cannot be effectively disinfected with it [8]. References [1] C. Prasse, D. Stalter, U. Schulte-Oehlmann, J. Oehlmann, and T. A. Ternes, “Spoilt for choice: A critical review on the chemical and biological assessment of current wastewater treatment technologies,” Water Res, vol. 87, pp. 237–270, Dec. 2015, DOI: 10.1016/j.watres.2015.09.023. [2] “chlorine as disinfectant for water.” https://www.lenntech.com/processes/disinfection/chemical/disinfectants-chlorine.htm (accessed Oct. 11, 2022). [3] “Understanding Sodium Hypochlorite | Treatment Plant Operator.” https://www.tpomag.com/editorial/2013/12/understanding_sodium_hypochlorite_wso (accessed Oct. 11, 2022). [4] S. Hariganesh, S. Vadivel, D. Maruthamani, and S. Rangabhashiyam, “Disinfection by-products in drinking water: detection and treatment methods,” Disinfection By-products in Drinking Water, pp. 279–304, 2020, DOI: 10.1016/B978-0-08-102977-0.00013-5. [5] S. Rajkhowa, “Heat, solar pasteurization, and ultraviolet radiation treatment for removal of waterborne pathogens,” Waterborne Pathogens, pp. 169–187, 2020, DOI: 10.1016/B978-0-12-818783-8.00009-8. [6] J. Wang and S. Wang, “Removal of pharmaceuticals and personal care products (PPCPs) from wastewater: A review,” J Environ Manage, vol. 182, pp. 620–640, Nov. 2016, DOI: 10.1016/j.jenvman.2016.07.049. [7] E. Lakshmi, M. Priya, and V. S. Achari, “An overview on the treatment of ballast water in ships,” Ocean Coast Manag, vol. 199, Jan. 2021, DOI: 10.1016/j.ocecoaman.2020.105296. [8] M. J. Brandt, K. M. Johnson, A. J. Elphinston, and D. D. Ratnayaka, “Disinfection of Water,” Twort’s Water Supply, pp. 475–511, 2017, DOI: 10.1016/B978-0-08-100025-0.00011-9.