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As China's economic and social development of urbanization, sludge production is also growing. Sludge contains large amounts of harmful substances and are not stable organic matter, if handled or disposed of improperly, will form a hazardous environment. Currently are generally taken for sludge dewatering direct disposal method, but high moisture content of dewatered sludge, bulky, high disposal costs. Thus, cost-effective disposal of sludge to reduce sludge production without affecting the performance of the sludge and effluent standards, have been highlighted as the current sewage treatment plant must be addressed. In this study, analysis and comparison of the advantages and disadvantages of different methods of sludge reduction, based on the proposed ultrasonic coupling ClO 2 lysed sludge reduction technology ideas, carry out small-scale and pilot studies . Results are as follows: The pilot scale to 2.4 m 3 / d of SBR system, its energy density residual sludge loud ultrasonic treatment, effects of different solid content, sound energy density and action time sludge cell disruption effects. The results show that the energy density 0.5 3 .0 W / mL, the solid content of 1.0% 1 .5% of the excess sludge by ultrasonic action, the supernatant SCOD was linearly increased with duration of action; sound energy density at 1.0 3 .0 W / mL, the solid content of 0.25% 0 .5% of the excess sludge The role of ultrasound, the supernatant SCOD was gentle with the role of time slowly increased. Loud ultrasonic energy density is more suitable for higher solid content of the sludge cell disruption; At this point, the supernatant SCOD increase and decrease MLSS and NH 4 -N , TN and TP increases were positively correlated with the sound energy density. The role of ultrasound 6min, the sludge morphology has been destroyed. Compared two groups of SBR system, in which a discharge of sludge SBR 2/3 of the energy density 1W/mL using ultrasonic treatment after 6min back to the reactor to study the effect of sludge reduction system and its impact on the effect of sewage treatment systems . The results showed that, SS, COD, TN and NH 4 -N removal efficiency did not change significantly, only slightly higher than the control effluent TP concentrations reactor effluent quality system still to maintain compliance. Sludge net loss of about 2.9kg, a decrease of about 45%, sludge reduction effect is remarkable. Through single factor experiment investigated ClO 2 chemical lysis. The results show that ClO 2 action about 1h, the sludge microorganisms in the intracellular portion of material extracted into the aqueous phase, resulting supernatant SCOD, NH 4 -N, TN and TP is increased. ClO 2 optimal dosage of 6mg / g dry sludge, suitable reaction time was 40 min, the optimum temperature at 35 ℃. Three factors and three levels orthogonal experiment results show that the ultrasonic coupling ClO 2 of excess sludge cell disruption factors influencing the efficiency order: ultrasonic time gt; sound energy density gt; ClO 2 dosage, optimum treatment conditions: ultrasonic sound energy density 1w/mL, the role of time 6min, ClO 2 dosage of 6mg / g dry mud.
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