Unidad Profesional Interdisciplinaria en Biotecnologia, Instituto Politecnico, Ticoman, D.F., México.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2009 Nov;44(13):1449-56. doi: 10.1080/10934520903217716.
Wastewater produced in the contaminated soil washing was treated by means of coagulation-flocculation (CF) process. The wastewater contained petroleum hydrocarbons, a surfactant, i.e., sodium dodecyl sulfate (SDS) as well as salts, brownish organic matter and other constituents that were lixiviated from the soil during the washing process. The main goal of this work was to develop a process for treating the wastewaters generated when washing hydrocarbon-contaminated soils in such a way that it could be recycled to the washing process, and also be disposed at the end of the process properly. A second objective was to study the relationship among the coagulant and flocculant doses and the pH at which the CF process is developed, for systems where methylene blue active substances (MBAS) as well as oil and greases were present. The results for the selection of the right coagulant and flocculant type and dose, the optimum pH value for the CF process and the interactions among the three parameters are detailed along this work. The best coagulant and flocculant were FeCl(3) and Tecnifloc 998 at doses of 4,000 and 1 mg/L, correspondingly at pH of 5. These conditions gave color, turbidity, chemical oxygen demand (COD) and conductivity removals of 99.8, 99.6, 97.1 and 35%, respectively. It was concluded that it is feasible to treat the wastewaters generated in the contaminated soil washing process through CF process, and therefore, wastewaters could be recycled to the washing process or disposed to drainage.
受污染土壤清洗产生的废水采用混凝-絮凝（CF）工艺进行处理。废水中含有石油烃、表面活性剂十二烷基硫酸钠（SDS）以及盐分、褐色有机物和其他在清洗过程中从土壤中浸出的成分。这项工作的主要目标是开发一种处理方法，以回收经污染土壤清洗后产生的废水并在处理过程结束时进行适当处置。第二个目标是研究在存在亚甲蓝活性物质（MBAS）以及石油和油脂的情况下，混凝剂和絮凝剂剂量与 CF 工艺开发的 pH 值之间的关系。本工作详细介绍了选择合适的混凝剂和絮凝剂类型和剂量、CF 工艺的最佳 pH 值以及三个参数之间的相互作用的结果。最佳的混凝剂和絮凝剂分别是 FeCl(3)和 Tecnifloc 998，剂量分别为 4000 和 1mg/L，pH 值为 5。这些条件下的颜色、浊度、化学需氧量（COD）和电导率去除率分别为 99.8%、99.6%、97.1%和 35%。结论是，通过 CF 工艺处理受污染土壤清洗过程中产生的废水是可行的，因此，废水可以回收用于清洗过程或排放到污水中。
