基于鸟粪石沉淀法高效回收磷石膏渗滤液中的磷  

Efficient recovery of phosphorus from phosphogypsum leachatebased on struvite precipitation

作　　者：马竟峰 吴翔 方号源 梅可 江珊 朱书景 MA Jingfeng;WU Xiang;FANG Haoyuan;MEI Ke;JIANG Shan;ZHU Shujing(College of Resources and Environment,Hubei University,Wuhan 430062,China)

机构地区：[1]湖北大学资源环境学院,湖北武汉430062

出　　处：《能源环境保护》2024年第5期175-184,共10页Energy Environmental Protection

基　　金：区域开发与环境响应湖北省重点实验室开放基金(2023(C)002);湖北省自然科学基金面上资助项目(2023AFB641)。

摘　　要：磷石膏渗滤液是磷石膏堆存时产生的液体,具有磷含量高、pH低、腐蚀性强和重金属含量高等特点。如果这些渗滤液随时间推移渗入地下,将严重污染地下水和地表水,对周边流域环境以及人体健康造成严重影响。利用鸟粪石沉淀法从磷石膏及其渗滤液中回收磷源,制备有价材料渗滤液基-鸟粪石结晶(PSL-S)。其核心在于通过转换渗滤液中磷的原矿相,提高有价组元回收率,实现工业固废替代纯试剂制备鸟粪石,解决了纯试剂制备鸟粪石价格高昂、磷石膏渗滤液中有价组元大量浪费的问题。设置Mg/P摩尔比、N/P摩尔比和pH 3个变量,选取渗滤液中磷回收率和PSL-S的鸟粪石纯度2个指标,通过单因素影响探究实验与优化正交试验,结合物相分析,得出了制备渗滤液基-鸟粪石结晶(PSL-S)的最优路径。当N/P摩尔比为5∶1,Mg/P摩尔比为1.6∶1,pH为9.5时,制备效果最佳,此时PO_(4)^(3-)回收率为87.73%、PSL-S的鸟粪石纯度为78.24%。PSL-S的成功制备,实现了磷石膏渗滤液高效资源化利用,显著降低了鸟粪石的生产成本,为磷化工废物的资源化利用提供了参考。Phosphogypsum leachate is a liquid produced during phosphogypsum stacking.It has the characteristics of high phosphorus content,low pH,high corrosivity,and high concentrations of heavy metals.If it seeps into the ground over time,it will seriously pollute the groundwater and surface water and pose a significant threat to the surrounding basin environment and human health.In this study,a struvite precipitation method was proposed to recover phosphorus sources from phosphogypsum and its leachate to prepare valuable percolate-based struvite crystal(PSL-S).The core idea is to improve the recovery rate of valuable components by converting the raw mineral phase of phosphorus in the leachate,which enables the production of struvite using industrial solid waste instead of pure reagents,thereby solving two issues:the high price of struvite prepared by pure reagents and the substantial waste of valuable components in phosphogypsum leachate.The study involved three variables:Mg/P molar ratio,N/P molar ratio,and pH.Two indicators,namely,the phosphorus recovery rate in leachate and the purity of struvite from PSL-S,were selected.Through a combination of single-factor influence experiments and optimization orthogonal experiments,combined with phase analysis,the optimal conditions for the preparation of PSL-S were obtained,specifically,when the N/P molar ratio was 5∶1,the Mg/P molar ratio was 1.6∶1,and the pH value was 9.5,with a phosphate recovery rate of 87.73%and a PSL-S preparation purity of 78.24%.The successful preparation of PSL-S enables the efficient resource utilization of phosphogypsum leachate,greatly reduces the production cost of struvite,and provides technical support for the resource utilization of phosphorus chemical waste.

关 键 词：鸟粪石沉淀法 磷石膏渗滤液 鸟粪石 优化正交实验 固废资源化 

分 类 号：X705[环境科学与工程—环境工程]