绿色无氯混凝剂调理协同厌氧消化污泥的效果和机理研究OA

To address the challenges of dewatering synergistic anaerobic digestion sludge and the issue of chloride ion introduction into filtrate by chlorine-containing agents,a chlorine-free polysilicate aluminum ferric(PSAF)conditioner was developed.Using synergistic anaerobic digestion sludge from a wastewater reclamation plant in Beijing as the test material,the conditioning effectiveness and mechanism of PSAF were investigated.Results show that when the volumetric dosage reaches 4%or higher,PSAF demonstrates a clear performance advantage.At a 4%dosage,the strength of the conditioned sludge flocs was enhanced,the floc size increased by 69.7%compared with that treated with polyaluminum ferric(PAF),the filtrate yield rate accelerated by 5%,and the dewatered cake moisture content decreased by 9.8%.Analysis of chloride ion(Cl-)concentration in the filtrate revealed that PSAF conditioning followed by dewatering reduced Cl-levels by approximately two-thirds compared to conditioning with chlorine-containing agents,thereby substantially mitigating chloride-induced corrosion on subsequent pipelines and equipment.PSAF synthesized with an Al/Fe molar ratio of 1∶2 and an(Al+Fe)/Si molar ratio of 4∶1 exhibitd a three-dimensional amorphous block structure.It achieved superior removal of soluble extracellular polymeric substances(S-EPS)compared with PAF,primarily through enhanced adsorption and network capture,leading to better conditioning performance.A comparative analysis with conventional aluminum and iron salts indicates that it is feasible.