Kinetic Study and Optimum Control of the Ozone/UV Process Measuring Hydrogen Peroxide Formed In-situ

Abstract

This study was conducted to develop a kinetic model of the ozone/UV process by monitoring the trend of in-situ hydrogen peroxide formation. A specifically devised setup, which could continuously measure the concentration of hydrogen peroxide as low as 10 μg/L, was used. The kinetic equations, comprised of several intrinsic constants with semi-empirical parameters (k_chain and k_R3) were developed to predict the time varied residual ozone and hydrogen peroxide formed in situ along with the hydroxyl radical concentration at steady state,[OH°]_ss, in the ozone/UV process. The optimum ozone dose was also investigated at a fixed UV dose using the removal rate of UV absorbance at 254 nm (A₂₅₄) in raw drinking water. The result showed that the continuous monitoring of hydrogen peroxide formed in situ in an ozone/UV process could be used as an important tool to optimize the operation of the process.

Keywords:

• Ozone
• Ozone/UV Process
• Photolysis
• Hydrogen Peroxide
• Hydroxyl Radical

ACKNOWLEDGMENT

This subject was supported by Ministry of Environment as “The Eco-technopia 21 project”.

Notes

*Referenced by Hoigné, Staehelin, and Bader mechanism and Gordon, Tomiyasu, and Fukutomi mechanism in the Book of Ozone in Water treatment (Langlais et al., 1991).