Virginia Polytechnic and State University, Civil and Environmental Engineering, 418 Durham Hall, Blacksburg, Virginia 24061, United States.
Retired, Cincinnati, Ohio 45230, United States.
Environ Sci Technol. 2024 Mar 26;58(12):5606-5615. doi: 10.1021/acs.est.4c00583. Epub 2024 Mar 12.
Gaps in the United States Environmental Protection Agency (US EPA) Lead and Copper Rule (LCR) leave some consumers and their pets vulnerable to high cuprosolvency in drinking water. This study seeks to help proactive utilities who wish to mitigate cuprosolvency problems through the addition of orthophosphate corrosion inhibitors. The minimum doses of orthophosphate necessary to achieve acceptable cuprosolvency in relatively new copper pipe were estimated as a function of alkalinity via linear regressions for the 90th, 95th, and 100th percentile copper tube segments ( > 0.98, = 4). Orthophosphate was very effective at reducing cuprosolvency in the short term but, in some cases, resulted in higher long-term copper concentrations than the corresponding condition without orthophosphate. Alternatives to predicting "long-term" results for copper tubes using simpler bench tests starting with fresh Cu(OH) solids showed promise but would require further vetting to overcome limitations such as maintaining water chemistry and orthophosphate residuals and to ensure comparability to results using copper tube.
美国环保署（US EPA）的铅和铜法规（LCR）存在一些漏洞，使一些消费者及其宠物容易受到饮用水中高铜溶剂的影响。本研究旨在帮助那些希望通过添加正磷酸盐腐蚀抑制剂来减轻铜溶剂问题的积极主动的公用事业公司。通过对 90%、95%和 100%的铜管段（>0.98，=4）进行线性回归，估算了在相对较新的铜管中实现可接受的铜溶剂所需的正磷酸盐最小剂量，这是基于碱度的函数。正磷酸盐在短期内非常有效地降低了铜溶剂的溶解度，但在某些情况下，长期铜浓度比没有正磷酸盐的相应条件下更高。使用从新鲜 Cu(OH) 固体开始的更简单的台式测试来预测铜管的“长期”结果的替代方法显示出了希望，但需要进一步审查，以克服维持水化学和正磷酸盐残留以及确保与使用铜管的结果可比性等限制。
