Frequently Asked Questions

“Isn’t medium pressure UV and Hydrogen Peroxide really the best AOP process?”

The combination of medium pressure UV and Hydrogen Peroxide is a well known AOP process, but it is not the only one. Combinations of low pressure UV, Hydrogen Peroxide and/or Ozone in many cases offer advantages in terms of operating costs, power consumption, removal efficiency or footprint. ITT is able to offer both core technologies – UV and Ozone.

“Can Bromate be formed in the use of ozone AOP applications?“

Generally, the formation of Bromate is only possible if relevant quantities of Bromide are present in the water. If Bromide is present, the innovative combination of Ozone with Hydrogen Peroxide allows a significant reduction of the direct reaction of Ozone with Bromide, often resulting in minimal Bromate formation.

“How can a combination of O₃, H₂O₂ and UV be less expensive than UV / H₂O₂?”

Different water contaminants should be treated with the most appropriate technology, tailored for the specific contaminant removal. The MiPROTM eco3 plus solution allows each single step to be optimally designed, resulting in lower total treatment cost.

“Why does low pressure UV irradiation work especially well with AOP?”

In many cases, photosensitive substances like NDMA or Amidotrizoic Acid are directly degraded very efficiently with UV light (254 nm). By photolysis, the UV light breaks down the chemical compounds and, thus, the degradation of the pollutants. In addition, the activation of Hydrogen Peroxide leads to effective oxidation of micropollutants.

WEDECO MiPRO™

An Advanced Oxidation Process (AOP) triggers the formation of OH radicals in the treated water. This process eliminates a wide variety of toxic compounds and dangerous micropollutants. ITT's Advanced Oxidation Processes - the MiPRO™ solutions - are based on three key components: Ozone, Hydrogen Peroxide, and UV light. By combining these technologies, the best solution for specific contaminants can be provided.

Our philosophy is to design each WEDECO MiPRO™ solution as the perfect complement to the existing process. The overall goal: ensured removal performance with the highest efficiency possible. The choice of the treatment technologies always depends on the target contaminant, considering on-site conditions such as footprint, flow rate and energy costs. ITT will supply the WEDECO MiPRO™ concept in three configurations:

	MiPRO™ eco₃	MiPRO™ photo	MiPRO™ eco₃ plus
Components	WEDECO Ozone system H₂O₂ dosing unit Injection / reaction unit Residual Ozone Destruction system	WEDECO UV system H₂O₂ dosing unit	WEDECO Ozone system H₂O₂ dosing unit Injection / reaction unit Residual ozone destruction system WEDECO UV system
Application	Most appropriate when pollutants are degraded effectively by the radical reaction path	Reduction of photosensitive substances e.g. NDMA	Various types of organic / inorganic micropollutants and other persistent substances
Advantages	Low operating costs Effective for a wide range of substances	Additional disinfection of the water by UV light	Besides micropollutants, photosensitive substances can also be reduced effectively Additional disinfection by UV light

This diagram compares the costs (per 1,000 gal of water treated) of various AOP scenarios based on power consumption, ozone dose, and H2O2 dose. The treatment goal of this case is the reduction of pesticides and pharmaceuticals at a water flow of 12 MGD. The costs include capital costs, footprint, oxygen, energy, H2O2 and maintenance.

Click on picture to enlarge.

Your solution: the Best Available Technology

Ideally, contaminated water should always be treated using the most efficient of the various processes. That's why the implementation of an Advanced Oxidation Process in a water or wastewater facility should always begin with the correct treatment process selection.

Application	Contaminants	O₃	UV	O₃+ H₂O₂	UV + H₂O₂	O₃+ H₂O₂ + UV
++ = Removal of 81 - 100% + = Removal of 51 - 80% 0 = Removal less than 50%
Industrial Chemicals	1,4-Dioxane	0	0	++	+	++
	MTBE	0	0	++	0	++
	NDMA	0	+	+	++	++
Pesticides	Atrazine	+	0	++	+	++
Pesticides	Bromacil	++	0	++	++	++
Pharmaceuticals	Diclofenac	++	+	++	++	++
	Carbamazepine	++	0	++	+	++
	Ibuprofen	+	0	++	+	++
	Amidotrizoic Acid	+	+	+	++	++
	Iohexol	+	+	++	++	++
	Hormones	++	0	++	+	++
Taste & Odor	Geosmin	++	0	++	+	++
Taste & Odor	MIB	++	0	++	+	++
Decolorization		++	0	++	0	++
TOC Removal		0	0	+	0	+
Disinfection		+	++	+	++	++