以高纯度蓝铁矿回收剩余污泥中磷——基于酸浸-纯化-铁电絮凝三步法  

Phosphorus recovery and high purity vivianite synthesis from residual sludge-Based on acid leaching-purificationelectrocoagulation three-stage process

作　　者：刘畅 魏桃员[1] 邱傲雪 廖武斌 洪辉 邓丹妮 谢世伟[1] LIU Chang;WEI Tao-yuan;QIU Ao-xue;LIAO Wu-bin;HONG Hui;DENG Dan-ni;XIE Shi-wei(School of Urban Construction,Wuhan University of Science and Technology,Wuhan 430065,China)

机构地区：[1]武汉科技大学城市建设学院,湖北武汉430065

出　　处：《中国环境科学》2025年第1期234-242,共9页China Environmental Science

基　　金：国家自然科学基金资助项目(51808415)。

摘　　要：提出了一种从剩余污泥焚烧灰中回收磷并合成高纯度蓝铁矿的新方法,该方法包括硫酸酸浸、树脂吸附除杂和铁电絮凝结晶3个步骤.本文采用响应曲面法研究了硫酸浸提焚烧污泥灰中磷酸盐(PO_(4)^(3-))的最优条件,并使用Box-Behnken法优化了铁电絮凝工艺参数.结果表明,在液固比37.60mL/g、硫酸浓度0.125mol/L、酸浸时间90.0min的条件下,酸浸法可提取焚烧污泥灰中92.80%的磷;732阳离子交换树脂在去除Ca^(2+)、Mg^(2+)、Al^(3+)、Fe^(2+/3+)等干扰磷酸盐沉淀的金属阳离子方面表现出显著效果;在溶液初始pH值为2.00、电流2.00A、反应时间30.0min的条件下,铁电絮凝过程能够去除溶液中所有的磷,并以纯度为97.37%的蓝铁矿形式回收.综上所述,本文提出的三步法可以从剩余污泥焚烧灰中回收磷,其中61.44%的磷可以作为高纯度蓝铁矿回收,且回收成本为14.66元/kg,而利润为30.68元/kg.An innovative technique for extracting phosphorus and synthesizing high-purity vivianite from incinerated sewage sludge ash was explored in this investigation,which experienced three principal stages,including leaching with sulfuric acid,purification via resin adsorption,and crystallization through iron electrocoagulation.The optimal conditions for acid leaching of phosphate(PO_(4)^(3-))from incinerated sewage sludge ash were examined by the response surface methodology,and the optimal operational parameters for the iron electrocoagulation process were determined by the Box-Behnken Design.The results indicate that phosphorus extraction efficiency of 92.80%was achieved at a liquid-to-solid ratio of 37.60mL/g,a sulfuric acid concentration of 0.125mol/L,and an acid leaching duration of 90.0min,the metal cations interfering with phosphate precipitation,such as Ca^(2+),Mg^(2+),Al^(3+),and Fe^(2+/3+)were efficiently removed by 732cation exchange resin,all phosphorus was removed from the solution successfully during the iron electrocoagulation process at an initial solution pH value of 2.00,a current of 2.00A,and a reaction time of 30.0min,meanwhile,vivianite with a purity of 97.37%were synthesized.The outcomes show that the three-step method facilitates phosphorus recovery from incinerated sewage sludge ash.61.44%of the phosphorus was retrieved as high-purity vivianite through the three steps;the recovery process costs 14.66yuan per kilogram product of vivianite and yields a profit of 30.68yuan.

关 键 词：树脂吸附 响应曲面法 焚烧污泥灰 磷酸盐 

分 类 号：X705[环境科学与工程—环境工程]