超声-酸化对活性污泥脱水性能的影响

Effect of Acidification and Ultrasound on Performance of Activated Sludge Dewatering

剩余污泥是废水生物处理中不可避免的副产物,污泥成分复杂、含水率高,其处理处置已成为污水处理厂的主要挑战之一。本试验以CST、含水率、泥饼固/水含量为指标,探究了酸化和超声的整合(A/US)工艺对污泥脱水性能的影响。研究表明,超声有利于促进EPS溶出,且酸性环境会导致污泥中EPS功能基团质子化,促进酸化水解,并有利于超声作用后的污泥再絮凝从而提高污泥过滤性能。

Activated sludge is the inevitable solid waste pollution during biological wastewater treatment.Addressing the environmental concern of excess sludge is a key challenge in municipal wastewater treatment pl,ants (MWTP).For sludge dewatering,the effects of process parameters on the A/US system sludge dewaterability represented by moisture content and CST were investigated.And to reveal the synergism of A/US system,a suite of analysis was implemented :the three-dimensional excitation emission matrix (3-DEEM)spectra of extracellular polymeric substances (EPS)such as proteins and polysaecharides,Zeta potential and particle size of sludge floes.The result revealed that US effects disrupted floe cells and accelerated the decomposition of EPS,releasing bound water into the bulk phase.In addition to enhancing hydrolysis of EPS,the acidic pH environment caused the protonation of functional groups on EPS,facilitating the refloceulation of US decomposed sludge for improved filterability.