| From the point of view of present treatment and disposal of sludge, disadvantages exist in both technical and financial aspects. Research and application of sludge disintegration technology plays an important role in biological treatment of sewage.In sludge disintegration technologies related to enhanced cryptic growth, ozonation has high disintegration efficiency with low energy consumption and no secondary pollution.This paper deals with theoretical and experimental research of ozonation sludge reduction. Main points of the content are analysis of influence of different operation conditions on disintegration and sludge characteristics before and after ozonation;analysis of the mechanism of sludge ozonation;establishment of ozonation reaction model;analysis of the biodegradability of ozonised sludge. The following results are achieved.Solid organics are mineralized partially and some still exist in the supernatant. The minimal effective ozone dose and the maximal disintegration efficiency exist. Protein and organic nitrogen released from solids are mostly mineralized. In the ozonation, SVI and pH decrease. The main production of ozonation is propionic acid.When the inflow gas flux is 90L/h, neutral condition favors the reaction. On this condition, hydroxyl radical reaction is the most important mechanism in ozonation which contributes to 78.7% particulate COD release rate.Ozonation reaction model is established and validated. In it ozone dose and ozone concentration are desired to be independent variables, and particulate COD release rate to be variable. Sludge ozonation disintegration efficiency is showed to have a direct ratio with ozone dose and concentration.Best ozone dose is 0.08 gO3/gSS on experiment condition. In the biodegradability analysis, autochonous substrate can be utilized as nourishment of microbial. Enhanced cryptic growth theory can be applicated in ozonation disintegration for sludge reduction, and it is showed to have favourable technical feasibility.
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