摘要
以河湖底泥沉降性能及重金属Cr^(6+)的去除为研究对象,对Ca(OH)_2和AlCl_3进行复配,合成改性钙铝絮凝剂,在单因素实验基础上,采用Box-Behnken中心组合实验和响应面分析对主要影响因素加以优化,得到了二次响应曲面模型以及优化的水平值。结果表明,对于底泥沉降性能和底泥重金属Cr^(6+)去除的最佳条件n(Al 3+)/n(Ca2+)依次为:6.04、6.08,絮凝剂投加量为2.96g/50g底泥、3.55g/50g底泥,pH值为3.03、4.81,最高沉降比为78.09%,Cr^(6+)最高去除率为33.41%。ESEM分析表明,固化/稳定化的机理主要是钙铝絮凝剂经过絮凝、吸附、水化等作用,将底泥中细小颗粒积聚,利于底泥脱水及有害废物微粒包裹,形成稳定的絮凝体。
With sludge settling property and the removal rate of Cr^(6+) as the measurable indicator,polymeric Ca(OH)2 and AlCl 3 flocculant was prepared.Based on one-factor experiments,through Box Behnken experiment design and response surface analysis(RSA),optimization grouping of these 3 main influencing factors was realized;aquadratic response surface model and optimum level values were obtained.The results showed that the settling ratio was 78.09%,the removal rate of Cr^(6+)33.41% under the optimum dosage of the ratio of n(Al 3+)/n(Ca 2+)6.04,6.08;the coagulant dosage of flocculant 2.96 g/50 g sediment,3.55 g/50 g sediment;pH 3.03,4.81,respectively.ESEM analysis revealed that a stable flocculating body would be formed in the flocculation,adsorption and hydration reaction beneficial to sediment dehydration and wrapped up heavy metals after the tiny particles in the sediment larger and polymerization.
出处
《湖北工业大学学报》
2017年第5期45-48,共4页
Journal of Hubei University of Technology
基金
湖北工业大学博士启动基金(BSQD13011)
湖北省大学生创新创业训练计划(201310500016)
关键词
底泥
絮凝剂
沉降比
重金属
Sludge
flocculant
settling property
heavy metal
