Besides disinfection and taste and odor control, chlorine is used for which of the following?

Besides disinfection and taste and odor control, chlorine is used for which of the following?

• A. oxidation of iron and manganese
• B. oxidation of hydrogen sulfide
• C. disinfection of repairs
• D. all listed

Answer: (D)

Chlorine acts as a versatile oxidizing agent and sanitizer in water treatment. Besides its roles in disinfection and controlling taste and odor, it oxidizes certain dissolved contaminants that cause color, staining, or odor issues, and it helps protect the system after maintenance. First, it oxidizes iron and manganese. In water, iron and manganese can be reduced to their soluble forms (Fe2+ and Mn2+). When chlorine is present, it oxidizes these metals to Fe3+ and Mn4+ compounds, which form insoluble precipitates that can be removed by filtration or settle out, reducing staining and turbidity. Second, it oxidizes hydrogen sulfide, the compound responsible for a rotten-egg smell. Oxidizing H2S converts it to sulfur or sulfate, eliminating the odor and improving water quality. Third, after repairs or maintenance in the distribution system, chlorine helps disinfect the newly exposed sections to prevent microbial growth, ensuring the repaired areas remain safe as the system continues to operate. Because chlorine can perform all of these functions, the option that includes all of them is the best choice.

Chlorine acts as a versatile oxidizing agent and sanitizer in water treatment. Besides its roles in disinfection and controlling taste and odor, it oxidizes certain dissolved contaminants that cause color, staining, or odor issues, and it helps protect the system after maintenance.

First, it oxidizes iron and manganese. In water, iron and manganese can be reduced to their soluble forms (Fe2+ and Mn2+). When chlorine is present, it oxidizes these metals to Fe3+ and Mn4+ compounds, which form insoluble precipitates that can be removed by filtration or settle out, reducing staining and turbidity.

Second, it oxidizes hydrogen sulfide, the compound responsible for a rotten-egg smell. Oxidizing H2S converts it to sulfur or sulfate, eliminating the odor and improving water quality.

Third, after repairs or maintenance in the distribution system, chlorine helps disinfect the newly exposed sections to prevent microbial growth, ensuring the repaired areas remain safe as the system continues to operate.

Because chlorine can perform all of these functions, the option that includes all of them is the best choice.