Core Advantages of Ultraviolet Disinfection Technology in Sewage Treatment

Ultraviolet (UV) disinfection technology has emerged as a mainstream alternative to traditional chemical disinfection in sewage treatment, thanks to its characteristics of **no chemical residues, high sterilization efficiency and convenient operation and maintenance**. It is particularly suitable for scenarios with stringent effluent quality requirements. Its core advantages are as follows: 1.  No chemical agent dosing and no disinfection by-products    UV disinfection relies on short-wave ultraviolet rays at 253.7 nm to damage the DNA of microorganisms. **It does not require the addition of chemical disinfectants such as chlorine or chlorine dioxide throughout the process**, fundamentally avoiding the formation of chlorinated disinfection by-products (e.g., trihalomethanes, haloacetic acids) and chlorine dioxide by-products (e.g., chlorite). It does not cause secondary pollution of water bodies, and the effluent can be directly used for reclaimed water scenarios such as river replenishment and municipal miscellaneous use. 2.  Broad sterilization spectrum, high inactivation efficiency and fast speed    - It has excellent inactivation effects on common bacteria (e.g., Escherichia coli), viruses and protozoa (e.g., Cryptosporidium, Giardia) in sewage. Especially for Cryptosporidium oocysts that are resistant to chlorine disinfection, UV can achieve an inactivation rate of over 99.9% within a few seconds.    - The disinfection process is a physical reaction with rapid response and short hydraulic retention time (usually only a few seconds). The equipment occupies a small area, making it suitable for the compact space requirements of upgrading and reconstruction projects of sewage treatment plants. 3.  Controllable operation cost and simple operation and maintenance    - There is no need to store and transport hazardous chemical agents (e.g., liquid chlorine), which reduces safety risks and chemical storage costs. Daily operation and maintenance only require regular cleaning of UV sleeves (to prevent scaling from affecting light transmittance) and replacement of lamp tubes (with a service life of about 8,000–12,000 hours), featuring a simple operation process.    - The equipment has a high degree of automation and can be adjusted in real time through online UV intensity monitors to adapt to fluctuations in sewage flow and water quality. 4.  Minimal impact on the physicochemical properties of water quality    UV disinfection does not change the physicochemical indicators of sewage such as pH value, dissolved oxygen and salinity, nor does it react additionally with ammonia nitrogen and organic matter in sewage. It ensures the stability of effluent quality, making it especially suitable for reuse scenarios sensitive to water quality parameters. 5.  Environmentally friendly and high safety    There is no risk of chemical agent leakage, which will not cause harm to operators and the surrounding ecological environment. There is no residual toxicity after equipment shutdown, allowing flexible emergency treatment. Compared with chemical disinfection, it is more in line with the requirements of environmental protection policies.