Additional Questions & Answers from the Webinar:
Q:Does the company use the units on the side of swimming pools to disinfectpool's water? If not, why? We actually do, this is part of the products manufacturedby Aquafine, a Trojan Technologies company. Please see www.aquafineuv.com . The units are capableof disinfecting organisms found in swimming pool water, and also removechloramines formed by the combination of pool chlorine and organic compounds.
Q:Have you considered using photocatalytic processes to supplement the injectionof H2O2? For example, UV radition indocent on TiO2 will produce H2O2. Yes, the challenge isfinding a material that would promote chemical reactions at a fast enough rateto use in a commercial product. This is a topic of ongoing research in manylabs.
Q:what was the placement of the lamps in reactor B? How far apart are theyspaced? Thediagram was shown as a general illustration, no distance scale is provided. Ingeneral, the spacing will be determined by the lamp UV output and transmittanceof water for UV light – the higher the lamp output and more transparent thewater to UV is, then the wider the spacing can be. Optimum placement isdetermined by fluid dynamics simulations.
Q:Wayne what is the point of diminished return when it comes to the number of UVlights per unit volume? In cross-section in a working channel, it would be thenumber of lamps per unit area. The optimum amount would depend on the range ofwater flow rates and water transparencies experienced at a site, as well as thepower of the individual lamps. Typically, a product will have a set value totreat water for a specified range of conditions to meet customer’s needs. For typical secondary WW disinfection in the markettoday, UV systems utilizing amalgam lamps use anywhere from 4 to 12 UV lampsper MGD (million gallons treated).
Q:Is there any disavantage of this technology? For UV disinfection, some organisms are more resistantthan others so more UV dose is required. Fortunately in drinking watertreatment, the most UV resistant viruses are easily treated by lowconcentrations of chlorine so a multi-barrier disinfection approach combinesthe advantages of UV and chlorine. For wastewater treatment, the elimination ofchlorine is desirable to eliminate harmful chemical byproducts from forming. One disadvantage to UV would be the lack of a residual(which is not the case for chlorination). Depending on regulations, a chlorineresidual is typically required in drinking water whereas it is not inwastewater. Since UV does not provide a residual, a reliable, accurate andtraceable UV sensor used to indicate/measure lamp output is an important partof the UV system.
Q:What happens to remnant of destroyed microorganism ? Organisms treated by UV are actually notkilled but are unable to reproduce, so they cannot multiply and infect a host.These organisms die naturally.
Q:How do you keep the optical surface interfacing with water clean for a longtime? Thesurfaces of the quartz sleeves used to protect the lamps are periodicallycleaned by wiping mechanisms (one illustrated for the Trojan UV3000+ module inthe presentation). Trojan Technologies uses a chemical-mechanical cleaningprocess.