Reduction and Heavy Metals Removal of Excess Sludge by Radio Frequency Discharge Plasma

Excess sludge is an unavoidable by-product in wastewater treatment. The conventional methods(landfill, incineration etc.) may cause secondary pollution. In this study, both reduction and heavy metals removal of excess sludge by radio frequency discharge plasma(RFDP) were investigated. The experimental results showed that RFDP was an effective removal method on total chemical oxygen demand (TCOD) and mixed liquid suspended solids(MLSS). Discharge process could also damage the cell structure of sludge, so that organic matter and heavy metals within the cell structure could enter the liquid phase. At the same time, combined with spectral diagnosis, the radical reactions was discussed. (paper)