Compiled by Isabel “Izzy” Medeiros and James P. Malley, Jr., Ph.D., University of New Hampshire
Owners and operators of UV technology are an important stakeholder group; these professionals have limited time and often prefer to remain anonymous when providing feedback. For this quarter, Operator’s Corner did not receive feedback in the Transportation sector and so has substituted a market summary. Feedback in the Water Reuse sector is reported based on 16 responses. (Market surveys suggest there are between 150 and 200 UV-based AOPs in use globally for water reuse purposes).
Transportation
The overall GUV market is driven by increasing public health concerns, a growing awareness of waterborne and airborne diseases (spurred by the COVID-19 pandemic) and a demand for chemical-free and environmentally friendly disinfection methods. Stringent government regulations on water and growing calls for them in air quality also play a significant role.
However, after 2024, the interest and applications of GUV in transportation systems, specifically the use of GUV as part of routine maintenance practices when buses, airplanes and trains (including subway cars) are not in service, have dropped to minimal levels, with less than 1% of new purchases being noted by leading manufacturers. There has been an interesting increase in products and applications that employ GUV in conveyance systems that transport produce and other products or packages.
Water Reuse
It is useful to define this market sector for the purposes of systems and operators reached out to in this column and to avoid confusion since water reuse can be defined in many different ways. This column focuses on systems that receive wastewater from municipal, domestic and industrial sources and then use advanced treatment techniques prior to providing and, in some cases, selling reclaimed water for diverse secondary purposes. These purposes include agriculture, industrial cooling processes and non-drinking urban uses, such as irrigation and prevention of saltwater intrusion.
Driven by escalating water scarcity and climate change, the market is forecast to grow at a compound annual growth rate (CAGR) averaging 9% to 12%, reaching between $45 and $55 billion by 2034. For this column, more conventional wastewater and drinking water treatment systems and their operators are excluded from the survey. In all cases, applications of UV technology in water reuse systems focus on advanced oxidation processes that generate radical oxidants for the purpose of removing organic micropollutants, such as NDMA, 1,4-dioxane and others. Quite naturally, these technologies also are being studied at the research and pilot-testing levels to determine effectiveness for the removal of PFAS compounds, microplastics (in micron and nanometer sizes) and other “forever chemicals.”
How is UV technology used in your water reuse facility?
All respondents indicated that they were applying UV and hydrogen peroxide systems to achieve advanced treatment. Ten respondents indicated that their system achieved additional virus-removal credits and served as a barrier for NDMA and 1,4-dioxane. Five facilities specifically noted that their systems were based on 95% removal of 1,4 dioxane. Three facilities stated that the primary goal of their UV hydrogen peroxide system was to eliminate low levels of pesticides to meet stringent national standards.
Has your facility evaluated UV technology to meet emerging PFAS standards?
All respondents indicated that PFAS is a growing concern for their water reuse facilities. Ten facilities indicated that they now routinely analyze for the PFAS compounds and precursors, and they meet standards and proposed guidance on unregulated compounds with their current MF/RO treatment technology. Two facilities indicated that they use granular activated carbon (GAC) as the final treatment step and plan to use that process to meet PFAS rules. One facility indicated that it will rely on PFAS source control regulations and, if needed, the water treatment facilities that take its reuse water will be upgraded to include GAC and/or ion exchange (IX).
Share the pros and cons of the UV technology in use at your facility.
Eleven facilities indicated that the process meets regulations and has required minimal increases in operation and maintenance compared to their other treatment processes. Four facilities stated the process was attractive because it was compact and did not produce sludges.
All facilities indicated that the operation and maintenance costs for the hydrogen peroxide parts of the system have been their biggest headaches. Nine facilities indicated that they continue to find ways to reduce the power costs of the process since they have been more significant than first planned for in the selection and design stages. Two facilities indicated that early problems with electronic ballasts, as well as lamp failures for the first two years of operation, have significantly improved. Three facilities indicated that they have increased maintenance efforts due to seasonal lamp fouling, resulting in frequent attention being needed for the wiper systems.
Share other observations or questions.
Four facilities observed that there were plans to implement new water reuse facilities in their part of the world, and these newer facilities were leaning towards GAC and IX processes driven by PFAS worries, while UV systems were used for virus inactivation credit.
Six facilities sought current thinking from our experts on whether UV LED lamps for advanced oxidation systems would be available in the next five to 10 years, and whether they would be an easy “change out.” Two facilities asked for more articles or information about how their current UV hydrogen peroxide systems would perform if microplastics or PFAS compounds did come into the UV units.