Paradis Charles J, Dixon Emma R, Lui Lauren M, Arkin Adam P, Parker Jack C, Istok Jonathan D, Perfect Edmund, McKay Larry D, Hazen Terry C
Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN.
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN.
Ground Water. 2019 Mar;57(2):292-302. doi: 10.1111/gwat.12770. Epub 2018 Apr 30.
The breakthrough curve obtained from a single-well push-pull test can be adjusted to account for dilution of the injection fluid in the aquifer fluid. The dilution-adjusted breakthrough curve can be analyzed to estimate the reaction rate of a solute. The conventional dilution-adjusted method assumes that the ratios of the concentrations of the nonreactive and reactive solutes in the injection fluid vs. the aquifer fluid are equal. If this assumption is invalid, the conventional method will generate inaccurate breakthrough curves and may lead to erroneous conclusions regarding the reactivity of a solute. In this study, a new method that generates a dilution-adjusted breakthrough curve was theoretically developed to account for any possible combination of nonreactive and reactive solute concentrations in the injection and aquifer fluids. The newly developed method was applied to a field-based data set and was shown to generate more accurate dilution-adjusted breakthrough curves. The improved dilution-adjusted method presented here is simple, makes no assumptions regarding the concentrations of the nonreactive and reactive solutes in the injection and aquifer fluids, and easily allows for estimating reaction rates during push-pull tests.
从单井推挽试验获得的突破曲线可以进行调整，以考虑注入流体在含水层流体中的稀释情况。经稀释调整后的突破曲线可用于分析，以估算溶质的反应速率。传统的稀释调整方法假定注入流体与含水层流体中非反应性溶质和反应性溶质的浓度比相等。如果该假设不成立，传统方法将生成不准确的突破曲线，并可能导致关于溶质反应性的错误结论。在本研究中，从理论上开发了一种生成经稀释调整的突破曲线的新方法，以考虑注入流体和含水层流体中非反应性溶质和反应性溶质的任何可能组合。新开发的方法应用于基于现场的数据集，并被证明能生成更准确的经稀释调整的突破曲线。本文提出的改进后的稀释调整方法简单，无需对注入流体和含水层流体中非反应性溶质和反应性溶质的浓度做任何假设，并且能够轻松地在推挽试验期间估算反应速率。
