生物沥浸污泥EPS的变化规律及对Zeta电位、污泥粒径的影响

摘要

To improve the sludge dewatering performance by thiobacillus thiooxidans,the changes of pH,total EPS content and EPS components,Zeta potential,floc size of sludge was investigated during bioleaching,and the correlation between pH,total EPS content,EPS components content and Zeta potential,floc size was analyzed.The result indicated that EPSp、EPSh sharply decreased at earlier bioleaching,then the decreasing trend became slow.The decreasion of EPSpy was slower in the process of bioleaching.pH,EPST,EPSpy,EPSp and EPSh had significant impact on Zeta potential.The relationships between EPST、EPSp、EPSh and Zeta potential were non-linear.Static neutralization of H+ and reduction of EPS charges resulted the decrease of Zeta potential.Zeta potential,EPST,EPSp,EPSh,EPSpy had significant impact on floc size.The relationships between EPST,EPSh,EPSp,EPSpy and floc size were non-linear.The increasing of floc size was caused by neutralization of H+,reducing of EPS charges and decreasing of steric hindrance between sludge flocs.%本研究以氧化硫硫杆菌生物沥浸提高污泥脱水性能为目的,考察生物沥浸过程中污泥pH值、EPS总量和组成、Zeta电位、粒径等的变化,研究pH值、EPS总量和组成变化对Zeta电位、粒径的影响.结果显示,生物沥浸初期污泥EPSp 、EPSh减少速度较快,随后减速变缓,EPSpy在整个过程中减少速度较慢;pH值、总EPS含量(EPST)、多糖含量(EPSpy)、蛋白质含量(EPSp)、腐殖质含量(EPSh)均对Zeta电位影响显著,EPST、EPSp、EPSh与Zeta电位相互关系为非线性关系,污泥Zeta电位降低是H+的静电中和作用和EPS电荷减少共同作用的结果;Zeta电位、EPST、EPShEPSp、EPSpy均对生物沥浸污泥粒径影响显著,EPST、EPSh EPSp、EPS py与污泥粒径的相互关系为非线性关系.大量H+的中和作用、EPS电荷的减少、污泥絮体间空间位阻的降低共同促进了污泥絮体颗粒的增大.