粉煤灰制备聚硅酸铁铝的结构特征与混凝机理  

Structural Characteristics and Coagulation Mechanisms of PSFA Prepared by Fly Ash

作　　者：唐海 冯玲 颜酉斌 刘桂中[2] 

机构地区：[1]安徽程大学生物与化学工程学院,安徽芜湖241000 [2]北京市环境保护科学研究院,北京100083

出　　处：《高校化学工程学报》2013年第6期1045-1050,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：安徽省教育厅自然科学重点项目(KJ2012A038,KJ2013A047);煤炭资源与安全开采国家重点实验室开放基金重点项目(08040102002)

摘　　要：以粉煤灰为原料制备聚硅酸铁铝（PSFA）混凝剂，在单因素试验的基础上采用响应面法对关键工艺参数进行了优化，用Box-Behnken建立并分析了二次多项式数学模型的有效性及各因素与浊度去除率（PNR）的交互作用。结果表明：3个因素对PNR的影响大小为粉煤灰／Na2CO3（w／w）〉pH〉熟化时间，最佳工艺参数为：粉煤灰／Na2C03（w／w）=1．51，pH=3．13以及熟化时间=25，79h，该条件F模型预测值PNR=94．46％，实际PNR为95．67％，该回归模型具有较好的预测性能，可用于指导生产实践。优化条件下，溶出液中A1、Fe平均浓度分别为4725mg·L-1和4236mg·L-1，相应的平均溶出率为32．8％、54．3％。由FT-IR推断PSFA是由多种金属元素构成单核或多核羟基配合物形成的无机高分子聚合物，由ξ-电位及激光衍射粒度分析表明PSFA具有很强中和胶体电荷以及吸附架桥能力。PSFA处理焦化废水相比聚合硫酸铁有更宽的pH适用范围（6～10）及更高的COD去除率。The coagulant ofPoly-Silicon-Ferric-Aluminum （PSFA） was prepared by using fly ash as the main raw material. Based on the single factor experiments, the key process parameters were optimized by the response surface methodology （RSM）. Using Box-Behnken method, the second order quadratic method was established, and the applicability of the model and the interaction between the model factors and the Percent NTU Removal （PNR） were analyzed. The results indicate that the effect order of the three factors on PNR is as follows： weight ratio of fly ash to Na2CO3〉pH〉aging time. The optimal technical parameters for achieving the highest PNR were obtained as following： weight ratio of fly ash to Na2CO3 is 1.51, pH value is 3.13 and the aging time is 25.79 h. Under above optimal conditions, the PNR reaches 94.46%, the average concentrations of A1 and Fe in the stripping liquid are 4725 and 4236 mg·L-1, and the corresponding average dissolution ratios are 32.8% and 54.3%, respectively. By the deduction of FT-IR, the PSFA is a type of inorganic high polymers and a combination of single/poly-nuclear hydroxyls complexes constructed by two or more metal elements. PSFA has strong capabilities of colloid charge neutralization and ＂bridge＂ adsorption, and when treating coking wastewater, compared with traditional PFS, the PSFA has a higher COD removal efficiency and a wider applicable pH range （6-10）.

关 键 词：粉煤灰 聚硅酸铁铝ζ-电位 红外光谱 激光粒度衍射 

分 类 号：Q813.11[生物学—生物工程]