Study On The Advanced Oxidation Technology Of Strong-field Ionization Discharge

The Advanced Oxidation Technologies, which have been applied to treat hazardous pollutants since the 1980s, have currently become one of the hot subjects in the environmental protection field both at home and abroad. But the methods available could not be applied to the environmental pollution control engineering by reason of low generating concentration of hydroxyl radicle, high operation cost and rigid reaction conditions. In order to broaden the research and application realm of AOTs and put to engineering use, a new approach was investigated producing high-concentration hydroxyl solution by strong-field ionization discharge and high-efficiency gas-liquid dissolution technique based on the key NSFC Project "Studies of Method and Application of Gas Molecules Ionized with Strong Electric Field at High Pressure" (No "60031001) and the NSTF Project "Studies on Treating Invasive Spread of the Introduced Species by Gas Ionization Discharge" (No.: 60371035), and was successfully applied to treat ship's ballast water. The main achievements are as follows:1. Activating gas molecules with accelerated electrons was realized by strong-field ionization discharge at atmospheric pressure. In the discharge chamber, the reduced electric field strength was E/n>400Td, the average energy of electrons was more than 10eV, the concentration of electrons over 1015/cm3. With this means, high-concentration and great-yield hydroxyl radicle could be produced by mixed gas of H2O and O2. This technology had the advantages of without catalyst, no byproducts and wastes.2. The obtained concentration of hydroxyl solution reached 20mg/L by strong-field ionization discharge and high-efficiency dissolution method, which met the need of engineering applications for its low operation cost and power consumption.3. The results of a series of experiments indicated that hydroxyl radicle could oxidize organic compounds and kill off microorganisms rapidly under low dose and ultimately discompose them into CO2, H2O and inorganic salts, the surplus hydroxyl radicle degenerated into H2O and O2, and that no harmful residue was left after the treatment. Itwas considered a green AOT by virtue of its clean treating process. It was regarded at present as the most efficient method producing high concentration hydroxyl radicle by strong-field ionization discharge, which overcame the main obstacles limiting the industrial applications of AOTs, and took a critical step toward engineerization.