超声及络合剂对剩余污泥中磷释放的影响

Effects of Ultrasound and Complexing Agents on Phosphorus Release from Excess Sludge

考察了超声时间、功率、络合剂种类及含量对污水厂剩余污泥磷释放的影响。结果表明,一定范围内提高超声功率、增加超声时间可促进污泥磷释放;4种络合剂中乙二胺四乙酸二钠(EDTA)对磷释放的促进效果最好。正交实验发现,影响超声、络合剂联合处理剩余污泥中PO^3-4-P释放因素由大到小依次为络合剂浓度,超声功率和超声时间,TP释放影响因素由大到小依次为络合剂含量、超声时间,超声功率,其优化条件为超声功率80W,超声时间90min,EDTA浓度15 mmol/L。此时污泥中PO^3-4-P、TP释放率分别为44.5%、50.1%,上清液中PO^3-4-P、TP的质量浓度分别为295.3 mg/L.335.3 mg/L,比对照组分别提高了2.13倍和2.08倍。

The effcts of ultrasonic time,power,complexing agent type and content on phosphorus release from excess sludge in sewap plant were invesigaed.The reuts showed that phosphorus release from sludge could be promoted by increasing ultrasound power and time in a certain range.Among the four complexing agents,cthylene diamine tetracetic acid(EDTA)had the best promoting effect on phosphorus releasc.Orthogonal testshowed that the infuencing factors on PO^3-4-P release from excess sludge were as follows,concentration of complexing agent,ulrasonic time andulrasonic power.Under the optimal conditions of ulrasonic power of 80 W,ulrasonic time of 90 min and EDTA concentration of 15 mmol/L,therelease rates of PO^3-4-P and TP in sludge were 44.5%and 50.1%,and the mass concentrations of PO^3-4-P and TP in supemnatant were 295.3 mg L and 335.3 mg/L,which were 2.13 times and 2.08 times higher than those in control group.