When standard water treatment methods reach their limits, Advanced Oxidation Process (AOP) steps in. AOP is the most powerful chemical oxidation technology available for water treatment, capable of breaking down contaminants that resist conventional methods — including pesticides, pharmaceutical residues, industrial chemicals, and endocrine disruptors.
The Science Behind AOP
AOP works by generating hydroxyl radicals (•OH), which are the strongest oxidizing agents that can be produced in water. With an oxidation potential of 2.8 volts, hydroxyl radicals are significantly more powerful than ozone (2.07V), hydrogen peroxide (1.78V), and chlorine (1.36V).
Hydroxyl radicals are generated by combining two or more oxidation methods. The most common approach in water treatment is combining UV light with ozone. When ozone-saturated water passes through a UV reactor, the UV energy breaks down ozone molecules, triggering a chain reaction that produces hydroxyl radicals. These radicals react with organic molecules in microseconds, breaking carbon bonds and fully mineralizing contaminants into simple, harmless end products: carbon dioxide and water.
What Can AOP Remove?
The power of AOP lies in its non-selectivity. While conventional methods target specific contaminant groups, hydroxyl radicals attack virtually any organic molecule they encounter. This makes AOP effective against a broad range of compounds that are difficult or impossible to remove by other means.
These include pharmaceutical and personal care products in municipal water supplies, persistent organic pollutants in industrial wastewater, taste and odor compounds from algal activity, pesticide residues in agricultural water, and chlorinated organic compounds such as trihalomethanes. In swimming pool applications, AOP eliminates chloramines — the compounds responsible for the characteristic pool smell and eye irritation.
How AOP Systems Are Configured
A typical AOP installation includes an ozone generator (fed by a PSA oxygen generator), an ozone injection and mixing system, a UV reactor, an ozone destruct unit, and an automated PLC control cabinet. The entire system operates continuously with real-time monitoring of ozone concentration, UV dose, and treatment performance.
Systems are available in a range of capacities. Standard industrial configurations handle flow rates from 12 to 110 cubic meters per hour, while purpose-built pool systems treat water volumes from 180 to 900 cubic meters.
When to Consider AOP
AOP is typically specified when other treatment methods are insufficient. If your water contains persistent organic compounds, if you need to meet very strict discharge limits, if you are treating water for reuse, or if conventional treatment is producing unacceptable byproducts, AOP should be evaluated as a solution.
While AOP systems represent a higher capital investment than basic UV or ozone alone, they deliver treatment outcomes that no other single technology can match. For applications where complete contaminant destruction is required, AOP is not just an option — it is the only option.