Systems using chlorine gas also have the disadvantage of producing toxic disinfection by-products. This presentation is a state-of-the-art review of chlorine dioxide (ClO2) used for high-rate disinfection of combined sewer overflow (CSO). Chlorine dioxide Chlorine dioxide is a more powerful oxidizing agent than chlorine, the disinfectant action of which is less pH-dependent than chlorine. * Chlorine is commercially available * Chlorine is very economical Disadvantages * Chlorine does not exterminate all bacteria. Chlorine gas; disadvantages: Chlorine is an extremely volatile and hazardous chemical and requires specific precautions for it to be shipped, stored, and used safely. It leaves a long-lasting residual. The following table shows these advantages and disadvantages. Contrary to chlorine, chloramines do not perish when the water lies still for a few days. switch to the use of chlorine with ammonia or the use of chlorine dioxide or ozone as the disinfectant. Chlorine was the original disinfectant used in US municipalities, with Jersey City being the first city to implement a chlorine-based system in 1908. Compare Effectiveness: Beachhead ClO₂ vs. Chlorine Bleach and the Rest. Highly effective disinfectant. We have already seen the dangers of uncontrolled use of chlorine (in bleach), but in a controlled environment, chlorination is highly cost effective and relatively safe. Hypochlorites are less pure than chlorine gas and are less dangerous. Ozone and chlorine dioxide present definite advantages and disadvantages over chlorination. However, chlorine dioxide is an inefficient disinfectant for viral agents and therefore its use is limited. Chlorine dioxide is a very effective bacterial disinfectant and it is even more effective than chlorine for the disinfection of water that contains viruses. Since the beginning of the twentieth century, when it was first used at a spa in Ostend, Belgium, chlorine dioxide has been known as a powerful disinfectant of water. Chlorine dioxide is often used as a biocide to disinfect water, hard surfaces and in some instances indoor air volumes using specialist fogging techniques. It is formed by mixing chlorine with ammonia. The review includes bench-, pilot-, and fullscale studies on the use of ClO2 as a disinfecting agent for a variety of wastewaters. Chlorine dioxide is used as a bleach at pulp mills, which make paper and paper products, and in public water-treatment facilities, to make water safe for drinking. Chlorine dioxide (ClO2) Ozone (O3) Ultraviolet Radiation (UV) What are some of their advantages and disadvantages? Chlorine dioxide has regained attention because it is effectively deactivates the chlorine-resistant pathogens Giardia and Cryptosporidium. Chlorine dioxide can be produced by mixing solutions, such as a solution of chlorine with a solution of sodium chlorite 329 . Because it is a hazardous gas, chlorine dioxide is always made at the location where it is used. Chlorine dioxide is a broad oxidant and sanitizing agent; it functions by disrupting cell membranes and protein synthesis. Each one of these disinfection technologies has its own unique advantages and disadvantages. Chlorine dioxide is a yellow to reddish-yellow gas that can decompose rapidly in air. Chlorine Chlorine (bleach) has the longest track record as a water disinfectant and remains the most widely used compound today. Chlorine dioxide is used for taste and odor control as well as disinfection. Because it is a hazardous gas, chlorine dioxide is always made at the location where it is used. At set time points, 4, 40, or 120 mL (as three 40 mL aliquots) samples were taken. A gaseous chlorine dioxide system for sterilization of healthcare products was developed in the late 1980s 853, 952, 953. It can be used as a gas or in an aqueous form. For comparison, chlorine is also shown. Disadvantages of chlorine: formation of halogenated by-products, possibility of unpleasant taste and odour, pH-dependent effectiveness, over time degradation of hypochlorite solutions.