Wastewater treatment operators are constantly on the lookout for ways to cut the costs, energy usage, and environmental impact associated with their operations. One of the areas in which they can do this is the disinfection stage, where wastewater that has already passed through the treatment process is further processed to remove any bacteria, viruses, fungi, and other elements that can cause health and environmental problems.
Wastewater can be disinfected using a variety of methods, some chemical, such as with chlorine, and some physical, such as irradiation with ultraviolet (UV) light. Both these approaches have their drawbacks, however. By-products from chlorine-based disinfection can be discharged with the effluent and impact ecosystems and downstream drinking water quality, while UV irradiation involves an expensive equipment setup and consumes a significant amount of energy.
Strict regulation impacts operations
“New emerging methods using strong oxidants like performic and paracetic acids are now seen as the best available technology because of their low capital investment and energy needs. When environment-friendly, chemical disinfection is a solution for the future,” says Patricia Aubeuf-Prieur, Marketing Manager at Kemira.
There are regulatory pressures to take into account too, such as the stricter requirements for bathing water quality introduced by the EU Directive 2006/7/EC, as well as the need to increase wastewater reuse because of climate change-induced water scarcity and more frequent extreme weather events.
“Bathing waters in the EU now need to meet much stricter limits in terms of bacteria levels, while climate change is causing a pressure to reuse wastewater in applications like agricultural irrigation and to be able to deal with storm-water overflows from sewage networks,” Patricia explains. “The upshot of all this is that we need to adopt new disinfection methods that are effective and energy efficient, and which do not impact our environment. One of such solutions is the Kemira KemConnect™ DEX.”
Tackling Olympic-sized challenges
KemConnect DEX is a chlorine-free disinfection system that can be used to treat all kinds of water, from raw water and industrial and municipal wastewater, to storm water overflows. The secret ingredient is performic acid, PFA for short – plus of course a healthy dose of chemistry expertise and smart technology.
“While the world’s elite athletes are busy going for gold at the Paris Olympics in 2024, KemConnect DEX could be winning awards of its own in the safe bathing water category.”
“Disinfection using chlorine or hypochlorite leads to the formation of a huge number of non-biodegradable compounds, some of which can be carcinogenic,” Patricia explains. “And while UV disinfection is effective, it’s also expensive because of the energy demands and the need to pre-treat the wastewater with sand filters prior to disinfection. KemConnect DEX has none of these drawbacks: PFA degrades very quickly and leaves behind no by-products, can be produced cost-effectively on site, and is suitable for disinfecting any kind of treated wastewater, regardless of quality,” she continues.
While the world’s elite athletes are busy going for gold at the Paris Olympics in 2024, KemConnect DEX could be winning awards of its own in the safe bathing water category. With some of the swimming events set to take place in the River Seine, the city of Paris will be legally bound to ensure that the river water meets the required standards. “KemConnect DEX is already making inroads in several European cities, including Berlin, Venice, Biarritz, and Perpignan, and we hope to be able to add Paris to that list soon,” notes Patricia.
In 2018, KemConnect DEX was evaluated at scale 1 by SIAAP, the Greater Paris Sanitation Authority, for their project of disinfecting the treated wastewater before discharging into river La Seine. The D.I.E (Direction de Innovation et de l´Environnement) of SIAAP has set a very comprehensive protocol to prove its efficiency and its zero-environmental impact with advanced analytical methods. The results are expected at the end of the first quarter and will be submitted to health and environmental authorities.
An award-winning solution
Since its launch in 2011, KemConnect DEX has picked up a number of notable awards and recognitions, including the global award in the “Innovation in water and/or wastewater management” category at the 2014 WEX Summit. “There is great demand across Europe for safe, reliable, and efficient disinfection solutions. KemConnect DEX is a great example of how we can develop solutions that work where they need to but leave no unwanted traces,” Patricia concludes.