中文摘要：

通过n（Ca）／n（Fe）为0．03～0．20的钙基聚合硫酸铁（Calcium—based Polyferric Sulfate，CaPFS）对武汉某河道富磷底泥（含磷540mg／kg、含水率97％）进行混凝浓缩脱水，并对固持磷于沉泥之中的过程展开研究。结果表明：对钙铁摩尔比为0．05的CaPFS，其投加量以铁计为c（Fe）=2．87μg／g时，经混凝沉降静置后其上清液含磷为0．05±0．003mg／L、沉泥抽滤液含磷为0．41±0．02mg／L、沉泥滤饼含磷为1610mg／kg，底泥中95．64％±1．94％的磷被固持于沉泥之中；而经同样投加量的市售聚合硫酸铁处理后，上清液含磷为0．25±0．02mg／L、沉泥抽滤液含磷为0．66±0．02mg／L、底泥仅87．54％±2．14％的磷被固持于沉泥之中。加入钙后的聚合硫酸铁CaPFS能有效地将底泥中的磷在混凝浓缩脱水时固持于沉泥之中，降低脱出水的含磷量，对有效防止河道底泥生态疏浚余水外排导致水体富营养化具有十分重要的作用。

英文摘要：

The phosphate rich dredging from one river in Wuhan was dewatered and phos - immobilized into the sediment in the process of coagulation by calcium - based polyferric sulfate （CaPFS） with Ca/Fe mole ratio from 0.03 to 0.20 and this dredging was 540 mg/kg phosphate, with 97 % moisture content. It showed that the phosphate content of the supernatant for dredging decreased to 0.05 ± 0.003 mg/L after coagulation by CaPFS with Ca/Fe mole ration of 0 .05 at the dosage of 2.87 μg/g. The P concentration of sediment and the filtrate of the sediment was t 610 mg/kg and 0.41 ± 0.02 mg/L. 95.64% ± 1.94 % of phosphate in the original dredging was transferred into the sediment by this coagulation process with CaPFS. These results were also compared with those treated by normal polyferric sulfate with the same dosage （The superuatant for dredging decreased to 0.25 ± 0.02 mg/L, sludge filtration liquid containing phosphorus was only 87.54% ±2.14% and 0.66 ±0.02 mg/L of phosphate was fixed in the mud sediment）. It was also shown that this modified CaPFS had good performance for phosphate transfer from dredging to the sediment by coagulation and the decreased P concentration of the supernatant was significant to prevent the eutrophication in the process of ecological dredging for city river channel.