以缓释肥的形式回收污泥溶解液中磷的研究

摘要

以聚合硫酸铁（PFS）为絮凝剂,单宁酸为助凝剂回收污泥溶解液中的磷。研究结果表明：在铁盐投加量为160mg/L,pH为8,单宁酸投加量为10 mg/L条件下,磷酸盐的回收率可达到97.0%。单宁酸促进了混凝沉淀物中磷的释放,表明利用该方法回收磷作为缓释肥的可行性。将沉淀物作为缓释磷肥施用于土壤中能够明显促进黑麦草的生长。%Polyferric sulfate（PFS） was selected as the coagulant,and tannic acid（TA） as the coagulant aid to develop an effective coagulation process on phosphorus recovery from dissolved sludge solution.The analytical results showed that the optimum effect was observed under the conditions of 160 mg/L coagulant,pH at 8 and 10mg/L TA,and the maximum recovery of phosphate could reach 97%.The coagulant aid tannic acid（TA） promotes phosphorus release from the coagulant precipitate,which indicates the possibility of phosphorus recovery from wastewater as a slow release fertilizer.Finally,the precipitate was added to soil to test its fertility on the growth of ryegrass.Findings of the experimental study clearly confirmed that the addition of precipitate significantly promoted the growth of ryegrass.