低强度超声波对低温下污水生物处理的强化效果及工艺设计

为了研究低温条件下超声波对污水生物处理的强化效果,采用强度0.3 W·cm-2的超声波对好氧活性污泥进行10 min的辐射处理,然后在4℃条件下进行模拟SBR(sequencing batch reactor)反应.以耗氧呼吸速率(oxygen uptake rate,OUR)、脱氢酶活性(dehydrogenase activity,DHA)和COD为指标,研究了低温条件下超声波对污泥生物活性以及有机物去除效果的改善.结果表明,低温条件下,经超声波处理后污泥活性可提高30%,COD的去除率也可保持常温水平.通过比较可以看出,低温条件下超声波的强化效果较常温条件下更为明显.本研究还以典型的城市二级处理污水处理厂和采用SBR工艺的污水处理厂为例,对低强度超声波在污水处理工艺中的设计和操作进行了说明.

Enhancement Effect of Low Intensity Ultrasound on Biological Wastewater Treatment System in Low Temperature and Design of Application on Biological Wastewater Treatment

This work aims to study the enhancement effects of low intensity ultrasound on biological wastewater treatment in low temperature. The activated sludge was irradiated by ultrasound with intensity of 0.3 W cm(-2) for 10 minutes, and then simulated SBR process in 4 degrees C. Oxygen uptake rate (OUR), dehydrogenase activity (DHA) and COD were determined to indicate the changes of sludge activity and the removal rate of organic matter after the ultrasonic irradiation in low temperature. Results showed that after ultrasonic enhancement, the sludge activity could be increased by 30%, and COD removal rate could keep the usual level as in the room temperature. Furthermore, the enhancement effect of ultrasonic irradiation was more significant in the low temperature than that in the room temperature. This paper also took the typical municipal wastewater secondary treatment technology and SBR technology as examples to illustrate the design and operation of the enhancement of biological wastewater treatment using low intensity ultrasound.