Soh Yeow Chong, Roddick Felicity, van Leeuwen John
School of Civil, Environmental and Chemical Engineering, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia.
Water Sci Technol. 2008;58(6):1173-9. doi: 10.2166/wst.2008.475.
Natural Organic Matter (NOM) from Myponga Reservoir, South Australia, was separated into four organic fractions based on their hydrophobic and hydrophilic properties using a sequence of non-ionic and ionic resins. NOM fractions were isolated for the purpose of determining the impact of alum coagulation on removal of these fractions in conventional water treatment, and their potential as precursors in the formation of disinfection by-products (DBP) and in supporting microbial growth. The NOM comprised VHA (very hydrophobic acids), SHA (slightly hydrophobic acids), CHA (charged hydrophilics) and NEU (neutral hydrophilics) fractions. These fractions were then jar tested with alum using low (50 mg/L), operational (100 mg/L) and very high (200 mg/L) doses to assess the removal capacities for these fractions in a conventional treatment plant. High-performance size exclusion chromatography-UV-DOC (HPSEC-UV-DOC) revealed that alum removed more of the hydrophobic and higher molecular weight components of NOM, but less of the NEU fraction and lower molecular weight components of NOM. Determination of biodegradable dissolved organic carbon (BDOC) indicated that the NEU fraction had the highest biodegradability, followed by the CHA, SHA and VHA fractions. The VHA fraction had the highest total-trihalomethane formation potential (t-THMFP), followed by NEU, SHA and CHA. The NOM not removed by alum coagulation had the potential to support microbial growth (NEU fraction), and disinfection by-product (DBP) formation (VHA and NEU fractions). To obtain treated water with lower overall residual NOM, other treatment methods would need to be applied in addition to alum coagulation in order to reduce the concentration of the neutral fraction.
利用一系列非离子和离子树脂，根据其疏水和亲水特性，将来自南澳大利亚米蓬加水库的天然有机物（NOM）分离为四个有机组分。分离NOM组分的目的是确定在常规水处理中明矾混凝对这些组分去除的影响，以及它们作为消毒副产物（DBP）形成前体和支持微生物生长的潜力。NOM包括VHA（极疏水酸）、SHA（微疏水酸）、CHA（带电荷亲水物）和NEU（中性亲水物）组分。然后使用低剂量（50 mg/L）、操作剂量（100 mg/L）和高剂量（200 mg/L）的明矾对这些组分进行烧杯试验，以评估常规处理厂中这些组分的去除能力。高效尺寸排阻色谱-紫外-溶解性有机碳（HPSEC-UV-DOC）显示，明矾去除了更多的NOM疏水和高分子量组分，但去除的NOM的NEU组分和低分子量组分较少。可生物降解溶解性有机碳（BDOC）的测定表明，NEU组分的生物降解性最高，其次是CHA、SHA和VHA组分。VHA组分的总三卤甲烷生成潜力（t-THMFP）最高，其次是NEU、SHA和CHA。未通过明矾混凝去除的NOM有支持微生物生长（NEU组分）和形成消毒副产物（DBP）（VHA和NEU组分）的潜力。为了获得总体残留NOM较低的处理水，除了明矾混凝外，还需要应用其他处理方法以降低中性组分的浓度。
