Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
J Environ Sci (China). 2010;22(1):15-22. doi: 10.1016/s1001-0742(09)60069-3.
Low-cost, easy-maintenance and high-efficiency decentralized wastewater treatment technologies are urgently needed in rural areas of China. Processes with high potential for phosphorus removal are of great interest. However, commonly used treatment methods often do not meet the strict criteria for removing phosphorus from rural wastewater. In order to search an economic and simple technology for phosphorus removal from the common bio-technologies effluent, seven soil types collected from different rural areas in China were investigated for their ability to remove phosphorus. X-ray diffraction (XRD) was used to analyse the mineral structure, and inductively coupled plasma optical emission spectrometer (ICP-OES) was used to analyse the geochemical composition of the soil samples. Three primary minerals--quartz, albite and montmorillonite - were clearly detected. The samples were divided into two soil types, acidic soils and alkaline soils, based on their pH values. The geochemical composition study indicated that a higher percentage of Ca and Mg occurred in alkaline soils (pH > 8) than in acidic soils (pH < 6.5). Adsorption isotherms from batch experiments fitted the Langmuir and Freundlich models well, the maximum P adsorption capacities ranged from 0.256 to 1.598 mg P/g, indicating a high phosphorus removal potential for all of these soils. The P fractions extracted revealed that the sum of NaOH-extracted inorganic P (NaOH-Pi) was the major P component in the acidic soils, and CaCO3-bound phosphorus (Ca-P) in the alkaline soils. Dynamic adsorption simulation showed that these soils have the ability to remove phosphorus from wastewater.
低成本、易维护且高效的分散式污水处理技术在中国农村地区亟待开发。具有高除磷潜力的工艺受到广泛关注。然而，常用的处理方法往往不能满足农村污水除磷的严格标准。为了从常见的生物技术废水中寻找一种经济且简单的除磷技术，研究了从中国不同农村地区采集的 7 种土壤类型去除磷的能力。采用 X 射线衍射（XRD）分析矿物结构，电感耦合等离子体发射光谱仪（ICP-OES）分析土壤样品的地球化学组成。明显检测到三种主要矿物——石英、钠长石和蒙脱石。根据 pH 值将样品分为酸性土壤和碱性土壤两种类型。地球化学组成研究表明，碱性土壤（pH>8）中 Ca 和 Mg 的百分比高于酸性土壤（pH<6.5）。批量实验的吸附等温线很好地符合 Langmuir 和 Freundlich 模型，最大 P 吸附容量范围为 0.256 至 1.598mg P/g，表明所有这些土壤都具有很高的除磷潜力。提取的 P 组分表明，NaOH 提取的无机磷（NaOH-Pi）是酸性土壤中的主要 P 成分，而碱性土壤中的 CaCO3 结合磷（Ca-P）。动态吸附模拟表明，这些土壤具有从废水中去除磷的能力。
