离子交换法选择性回收污泥厌氧消化液中的磷

为探讨高效选择性回收污泥厌氧消化液中磷的离子交换方法,采用静态实验和动态实验研究了4种阴离子交换树脂（D213、D202、D301和DSQ）的磷回收性能,筛选了适合富磷污泥厌氧消化液选择性磷回收的高交换容量树脂。实验结果表明,D213、D202、D301和DSQ 4种树脂对正磷浓度为70 mg/L的厌氧消化液进行动态处理时,其最大穿透体积分别为3、7、17和90 BV;DSQ树脂磷交换容量远高于其他3种树脂,达到6 860 mg P/L湿树脂,是目前报道的高磷交换容量树脂的3~4倍;DSQ树脂能有效地抵抗厌氧消化液中有机质和硫酸根等阴离子的干扰;用NaOH溶液再生DSQ树脂并回收磷,磷洗脱率超过96%,洗脱液是高浓度含磷液,可作为磷矿石的优质替代品。研究表明,DSQ树脂是一种高效选择性分离磷的树脂,适用于污泥厌氧消化液的磷回收。

Selective phosphorus recovery from anaerobic digestion supernatant of sewage sludge by ion exchange

In order to explore the ion exchange method for high-performance selective phosphorus recovery from anaerobic digestion supernatant of sewage sludge,both static and dynamic experiments were used to investigate phosphorus recovery performances of four kinds of anion exchange resins（D213,D202,D301 and DSQ）,and the high-capacity ion exchange resin was filtered suitable for phosphorus recovery from phosphorus-rich anaerobic digestion supernatant of sewage sludge.The experimental results showed that the maximum penetrating volumes were 3 BV,7 BV,17 BV and 90 BV,respectively for four resins： D213,D202,D301 and DSQ when the dynamic treatment of anaerobic digestion supernatant was carried out with 70 mg / L of the influent PO3 4-P concentration.The phosphorus exchange capacity of resin DSQ,which could attain 6 860 mg P / L wet resin,was far higher than that of the other three resins,and was three to four times that of resins with high phosphorus exchange capacities reported at present.The resin DSQ could effectively withstand interference of the organic matter and sulphate and other anions in the anaerobic digestion supernatant.The washing rate was over 96% when NaOH solution was adopted to regenerate the resin DSQ,and the washed liquor contained high-strength phosphorus which could be utilized as the fine substitute of phosphoric ore.This research indicated that resin DSQ was one kind of resin with high performances of selective phosphorus separation,which could be applied in the phosphorus recovery from anaerobic digestion supernatant of sewage sludge.