混凝前处理对猪场沼液MAP回收时抗生素残留的影响

养猪废水磷酸铵镁（MgNH₄PO₄·6H₂O，MAP）回收时会有大量抗生素转移至回收MAP固体中，采用混凝前处理去除沼液中抗生素减少后续回收MAP中抗生素残留.首先对比聚合硫酸铁（PFS）、壳聚糖（CTS）、阳离子型聚丙烯酰胺（CPAM）和非离子型聚丙烯酰胺（PAM）四种典型无机和有机混凝剂对抗生素去除效果.实验结果显示CPAM去除抗生素效果最好，四环素类抗生素（TCs）去除率为22.8%-44.8%，喹诺酮类抗生素（FQs）去除率为32.2%~70.3%，回收MAP固体中抗生素含量为TCs 8.6mg/kg~19.6mg/kg，FQs 0.8~12.33mg/kg.在此基础上，考察了pH值和CPAM投加量对CPAM去除抗生素的影响.当pH7.5-8.0、CPAM投加量为17.5mg/L时，TCs去除42.5%~50.6%，FQs去除率42.9%~66.3%；与没有混凝处理的沼液MAP回收相比，产物中TCs含量下降43.2%~54.1%，FQs含量下降50.1%~69.5%.

Influence of coagulation pretreatment on the residue of veterinary antibiotics in the process of struvite recovery from swine wastewater

Recently, significant antibiotic residue is detected in the recovery of magnesium ammonium phosphate (MgNH₄PO₄·6H₂O, MAP) from the digested livestock wastewater. In case MAP is adopted as fertilizer for the agriculcural use,the antibiotics will be transferred from soil to the plant, consequently do harm to human. In order to reduce antibiotic residues in the final products, coagulation was employed as the pretreatment method before MAP recovery from wastewater. Four coagulants, including PFS (polyferric sulfate), CTS (chitosan), CPAM (cationic polyacrylamides) and PAM(polyacrylamides) were employed to investigate their performance on antibiotic removal. Results revealed that PFS possessed the most effective performance by removing 22.8%~44.8% TCs and 32.2%~70.3% FQs from the wastewater, thereby reduced the antibiotic contents in the recovered solids to TCs 8.6mg/kg~19.6mg/kg, FQs 0.88~12.33mg/kg, respectively. Further experiments concerned the influences of pH and coagulant dosage showed that pH 7.5~8.0 and 17.5mg/L coagulant dosage were the optimal conditions for antibiotic removal, which significantly reduced 43.2%~54.1% TCs and 50.1%~69.5% FQs in the recovered products.