UV Treatment: Driving Global Momentum for Sustainable Wastewater Reuse

By Giuseppe Faretra, Regional Sales Manager for West and Central Europe, Nuvonic

Governments worldwide are striving to find effective solutions to address the planet’s environmental challenges. One area that’s coming into sharp focus is the treatment and reuse of municipal wastewater.

Wastewater treatment facilities play a vital role in maintaining public health by removing harmful contaminants from wastewater before being released into the environment. These contaminants may include pathogens like bacteria, viruses and parasites, which can cause a wide range of diseases, from cholera to hepatitis to typhoid. Treatment facilities rely on various disinfection and filtration methods to remove these pathogens and ensure that the treated water they release is safe for use in non-potable applications, such as irrigation and toilet flushing.

Chlorination has long been the go-to method for wastewater treatment. Still, concerns about its hazardous byproducts and the danger those byproducts pose to surrounding areas and human health have prompted many governments and municipalities to explore alternative disinfection methods.

Ultraviolet (UV) treatment has emerged as a popular and effective solution among those alternatives. The UV disinfection equipment market 1 is projected to grow from $5 billion in 2022 to $9.1 billion by 2027, with water and wastewater disinfection applications driving a majority of that growth.

UV wastewater treatment involves exposing wastewater to UV light and has numerous environmental advantages over chlorination. Primary among them is the ability of UV to eliminate a wide range of harmful contaminants from water without the need for adding chemicals. UV light damages the genetic material of microorganisms and renders them unable to reproduce – all without chemicals.

Governments can bolster their environmental stewardship by adopting chemical-free UV treatment for wastewater. With UV treatment, harmful chemicals are kept out of the ecosystem, and the strain on freshwater resources also is alleviated. That’s because treated wastewater can be used in lieu of fresh water for applications like irrigation, industrial processes and groundwater replenishment.

Implementing UV treatment systems also can help reduce the discharge of untreated or poorly treated wastewater into natural water bodies, like rivers and lakes. This safeguards the water quality of those bodies and protects the ecological balance of these sensitive ecosystems.

UV Treatment Shines Bright

The science around UV treatment has expanded significantly over the past two decades, dispelling previous misconceptions about its effectiveness. For example, it once was believed that UV was relatively ineffective against Cryptosporidium, a genus of protozoans that cause gastrointestinal illness. But recent improvements in UV technology have made it highly effective in inactivating Cryptosporidium 2, even more so than chlorine.

Moreover, UV treatment effectively removes emerging contaminants from wastewater, such as the residue from pharmaceuticals and personal care products. These substances, often not effectively removed by conventional treatment processes, can harm aquatic ecosystems and human health. UV treatment offers an additional layer of protection by breaking down and deactivating these harmful compounds.

UV treatment offers other key benefits. Because it is a relatively compact and modular technology, it easily can be integrated into existing wastewater treatment plants without requiring major infrastructure modifications. This makes it a cost-effective solution when compared to implementing entirely new treatment processes.

Additionally, UV treatment is rapid, allowing for quick and continuous operation. The disinfection occurs almost instantaneously, as soon as the wastewater is exposed to UV light. This enables efficient treatment even during peak-demand periods and ensures a reliable and consistent supply of treated wastewater for reuse.

From the wastewater facility operator’s point of view, replacing chemicals with UV treatment also can help to prevent accidents, mitigate risks and protect workers. For instance, UV treatment eliminates the need for storing and handling dangerous and highly flammable chemicals, thereby eliminating potential hazards such as the risk of fire.

UV Treatment in Action

UV wastewater treatment has played a crucial role in enabling countries and municipalities to achieve their sustainability goals. Singapore’s NEWater initiative (www.pub.gov.sg/watersupply/fournationaltaps/newater) is a prime example, producing high-grade reclaimed water through a combination of techniques. UV treatment plays a key role in ensuring that Singapore’s water is safe and free from harmful pathogens, contributing to the country’s water sustainability and reducing its reliance on imported water sources.

Another example is the Orange County Water District’s Groundwater Replenishment System (GWRS) [www.ocwd.com/gwrs/]. The system takes highly treated wastewater that previously would have been discharged into the Pacific Ocean and purifies it using a three-step treatment process consisting of microfiltration, reverse osmosis and UV light. GWRS has reduced the reliance on imported water and provides a sustainable and drought-resilient water supply for Orange County.

Embracing UV treatment as part of water reuse strategies is a game changer for governments and municipalities worldwide. By harnessing the power of UV technology, wastewater treatment facilities can play a pivotal role in building a more sustainable and water-wise future for communities around the world.

  1. UV Disinfection Equipment Market, Market and Markets, https://www.marketsandmarkets.com/Market-Reports/uv-disinfection-market-217291665.html
  2. Efficiency of chlorine and UV in the inactivation of Cryptosporidium and Giardia in wastewater, Published online 2019 May 13, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6513095/