Which method of disinfection uses mercury arc lamps?

The correct response is linked to the use of ultraviolet (UV) radiation as a disinfection method in wastewater treatment. UV radiation is effective for disinfection because it directly inactivates microorganisms by damaging their DNA or RNA, preventing them from replicating and causing infection.

Mercury arc lamps, a specific type of UV light source, are utilized because they emit ultraviolet light at wavelengths that are particularly effective for sterilizing water. The effectiveness of this method lies in its ability to reduce pathogens without introducing chemicals into the water, making it an attractive option for treatment processes.

Unlike chlorination and ozonation, which involve the addition of chemicals to disinfect water, or biological treatment methods that rely on microorganisms to break down waste, UV radiation focuses on utilizing light to achieve disinfection efficiently and effectively. This characteristic underscores the distinct nature of UV disinfection in the context of wastewater treatment.