Why Advanced Oxidation Process?
Water utilities are reporting a rising trend worldwide as far as problematic micropollutions in water resources are concerned. Traces of organic / inorganic pollutants like NDMA, MTBE, 1.4 Dioxan, and EDC are often found in ground and surface water.
Industrialization, intensive agriculture, as well as medical provisions for humans, all have contributed to the increase of contaminations. Once these micropollutants enter the human food chain via drinking water there is a long term risk to health, as well as human or animal genetic material. Traditional treatment methods are no longer sufficient to guarantee complete removal of these contaminants.
Increased pollutants in drinking water can also be attributed to climate and demographic changes as well. As a consequence, there is a higher risk of water scarcity and thus there will be an increasing demand for direct or indirect reuse of wastewater for drinking water purposes.
The Advanced Oxidation Process (AOP) is the ideal approach for removing these new types of water contaminations. AOP is the combination of two or more processes to generate hydroxyl radicals (OH radicals) or to increase the number of them. The OH radicals contribute to the oxidation of undesirable substances. Compared to other oxidants, the OH radical has a considerably higher oxidation potential.
Once hydroxyl radicals have formed in water, they immediately react to virtually all existing oxidizable substances. The high degradation performance and the quick reaction kinetics of this process are the formula for success when it comes to eliminating numerous persistent contaminants.
The Promix solution
Promix is an intelligent ozone introduction and reaction system enabling ozone treatment in an elegant, slender design, suitable for source water containing high levels of bromide.
Some water utilities have to deal with high levels of bromide in their water sources. The ozone oxidation (e.g. AOP treatment) of affected drinking water sources with ozone can lead to Bromate formation in the product water. Bromate in drinking water is undesirable as it’s a suspected human carcinogen. In fact, bromate in drinking water is regulated by the World Health Organization (less than 10 μg/l).
The Promix system uses ozone in a novel way to keep Bromate formation under control while simultaneously treating unwanted contaminants. In drinking water treatment, ozone oxidation is typically one of the most popular alternatives to chlorination as it does not produce THMs or other chlorinated by-products.
AOP solutions can also be simply implemented in retro fit situations by upgrading existing ozone systems. There is no need for altering civil structures or existing treatment chains.
Xylem provides Promix packaged treatment systems minimizing the overall footprint of the full oxidation solution. This AOP design can make large contacting systems obsolete and is the perfect choice for small and mid-sized waterworks.
Promix systems are available in various standardized treatment skids for flows from 30 to 420 m³/h. Larger flows utilize combinations of Promix skids or engineered-to-order solutions.
