This study investigates the scale inhibition performance of a commercial polyacrylic acid-based (PAA) antiscalant used for drinking water production and its molecular weight fractions (≤ 500 Da, ≥ 500 Da). The investigated antiscalant is used to prevent sulfate and carbonate scaling in treatment of drinking water sources by reverse osmosis or nanofiltration (RO/NF). Based on two complementary tests involving determination of induction time in a batch test and rate of flux decline in a lab-scale RO/NF plant, concordant results were obtained, proving that the overall performance of commercial PAA was controlled almost entirely by the higher molecular weight fraction. The low molecular weight fraction, which is potentially more permeable through the NF/RO membrane, showed poor inhibition against both sulfate and carbonate scalants. Furthermore, measurements on the assimilable organic carbon (AOC) by flow cytometry reveals that the low molecular weight PAA fraction has low biological stability, as its potential transport into the permeate of a NF270 nanofiltration membrane was inferred by elevated AOC values in the NF-permeate. These results are crucial information for water utilities, plant engineering, regulatory bodies and public authorities with respect to the possible operation of RO/NF especially in drinking water production.

本研究调查了用于饮用水生产的商用聚丙烯酸 (PAA) 阻垢剂的阻垢性能及其分子量分数（≤ 500 Da，≥ 500 Da）。所研究的阻垢剂用于通过反渗透或纳滤（RO/NF）处理饮用水源时防止硫酸盐和碳酸盐结垢。基于两项补充测试，包括确定批量测试中的诱导时间和实验室规模 RO/NF 设备中的通量下降率，获得了一致的结果，证明商业 PAA 的整体性能几乎完全由较高分子量的聚合物控制。重量分数。低分子量部分可能更容易通过 NF/RO 膜，但对硫酸盐和碳酸盐垢的抑制效果较差。此外，通过流式细胞术对可同化有机碳 (AOC) 的测量表明，低分子量 PAA 组分具有较低的生物稳定性，因为通过 NF 渗透物中升高的 AOC 值推断其可能转运到 NF270 纳滤膜的渗透物中。 。这些结果对于水务公司、工厂工程、监管机构和公共机构来说是关于反渗透/纳滤可能运行的重要信息，特别是在饮用水生产方面。