【摘要】 用血清瓶对城市污水处理厂活性污泥进行20天的厌氧消化反应,通过向厌氧消化系统中投加不同量的氯化铁（Fe Cl₃）,形成Fe/P=0.34∶1的空白组和Fe/P=0.67∶1、1∶1、1.5∶1、2∶1、2.5∶1的各实验组,考察不同Fe/P条件下厌氧消化系统中铁和磷酸盐的变化过程、蓝铁矿的生成情况、磷赋存形态的变化、氧化还原性和酸碱环境的变化等.结果表明:各实验组中大部分三价铁被还原,可提取亚铁浓度分别为103.72mg/L、200.50mg/L、298.43mg/L、425.28mg/L、602.37 mg/L和758.66 mg/L,相应的液相中PO^3-₄去除率分别为19.55%、45.94%、68.83%、92.52%、99.52%和99.53%,即亚铁浓度的增加与磷酸盐的去除存在一定的对应关系.通过XRD和SEM检测发现各实验组中均存在蓝铁矿,利用七级磷提取法对干污泥中磷的赋存形态进行分析,结果表明随着Fe/P的增加,不稳定结合磷从51.27%下降至10.11%,铁结合磷从10.91%增加到81.27%.通过对各实验组数据的对比分析,Fe/P=2∶1为蓝铁矿形成的最适铁磷比.同时,Fe Cl₃的投加会对系统中氧化还原环境和酸碱度产生一定的影响.此外,厌氧消化系统中氨氮（NH⁺₄）的产生量和挥发性脂肪酸（VFAs）转化率随Fe/P增加而增大.在蓝铁矿回收过程中,适宜的铁磷比能够以最小的铁投加量获得最大的磷回收率.更多还原

【Abstract】 In this study, serum bottles were used for 20 days of anaerobic digestion of activated sludge from municipal sewage treatment plants.Different amounts of ferric chloride（FeCl₃） were added to the Anaerobic digestion system to form blank groups with Fe/P=0.34∶1 and experimental groups with Fe/P=0.67∶1,1∶1,1.5∶1,2∶1 and 2.5∶1.The changes of iron and phosphate, formation of vivianite, occurrence form of phosphorus, oxidation reduction and acid-base environment changes under different Fe/P conditions were investigated.The results show that: In each experimental group, most of the ferric iron were reduced and the extractable ferrous iron concentrations were 103.72 mg/L,200.50 mg/L,298.43 mg/L,425.28 mg/L,602.37 mg/L and 758.66 mg/L,respectively.The removal rates of PO^3-₄ in the corresponding liquid phase were 19.55%,45.94%,68.83%,92.52%,99.52% and 99.53%,respectively, indicating that there was a certain correlation between the increase of ferrous concentration and the removal of phosphate.It was found by XRD and SEM that vivianite existed in all the experimental groups.The occurrence forms of phosphorus in dry sludge were analyzed by seven-stage phosphorus extraction method.The results showed that with the increase of Fe/P,the unstable bonded phosphorus decreased from 51.27% to 10.11%,and the iron-bound phosphorus increased from 10.91% to 81.27%.Through comparative analysis of the experimental data, Fe/P=2∶1 is the optimal Fe/P ratio for vivianite formation.At the same time, the addition of FeCl₃ had some impact on the redox environment and pH in the system. In addition, the production of ammonia nitrogen（NH₄⁺） and the conversion rate of volatile fatty acids（VFAs） in the anaerobic digestion system increased with the increasing of Fe/P.In the vivianite recovery process, the appropriate iron-phosphorus ratio can obtain the maximum phosphorus recovery with the minimum amount of iron injection.更多还原