AWWA ACE92118

An advanced oxidation process using ultrasound and ozone (sonozone) concomitantly was investigated in terms of its efficiency in oxidizing natural organic matter (NOM). The primary oxidizing species was assumed to be hydroxyl radicals. Thermal combustion of ozone in the cavitation bubble and its surroundings was proposed as the mechanism of OH generation. Using purified fulvic acid solutions, removal of up to 20% of the organic carbon was achieved when ozone and ultrasound were employed simultaneously. Over a similar time period, only 30% of the organic carbon was removed by ozone alone. The organic carbon removed by the sonozone process was shown from mass balances to be completely mineralized. As with other advanced oxidation processes, the efficiency of the sonozone process was inhibited by radical scavengers such as HCO- 3 and Cl-. A raw alkaline water sample was also submitted to sonozone treatment and no organic carbon was removed. After removing the alkalinity from the raw water sample, however, 90% of the TOC was removed by applying ozone and ultrasound.