Progress 10/01/13 to 09/30/18
Outputs
Target Audience:Scientists and colleagues; environmental consultants. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Provided training to graduate students. How have the results been disseminated to communities of interest?Through published journal articles and presentations at scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
We have generated data sets that have allowed us to determine the impact of soil properties and fluid distribution on the magnitude of fluid-fluid interfacial area. We have also delineated the effectiveness and representativeness of the measurement methods. This information can improve conceptual and mathematical models for characterizing transport and fate of contaminants in the subsurface. This, in turn, will enhance the accuracy of risk assessments and selection of remedial methods for site cleanup. The results have been published in peer-reviewed journal articles.
Publications
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Progress 10/01/15 to 09/30/16
Outputs
Target Audience:1. Students 2. Peers Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Training for students and post-docs How have the results been disseminated to communities of interest?journal article What do you plan to do during the next reporting period to accomplish the goals?continue experiments.
Impacts
What was accomplished under these goals?
Two different methods are currently used for measuring interfacial areas between immiscible fluids within 3-D porous media, high-resolution microtomographic imaging and interfacial partitioning tracer tests (IPTT). Both methods were used in this study to measure nonwetting/wetting interfacial areas for a natural sand. The microtomographic imaging was conducted on the same packed columns that were used for the IPTTs. This is in contrast to prior studies comparing the two methods, for which in all cases different samples were used for the two methods. In addition, the columns were imaged before and after the IPTTs to evaluate the potential impacts of the tracer solution on fluid configuration and attendant interfacial area. The interfacial areas measured using IPTT are 5 times larger than the microtomographic-measured values, which is consistent with previous work. Analysis of the image data revealed no significant impact of the tracer solution on NAPL configuration or interfacial area. Other potential sources of error were evaluated, and all were demonstrated to be insignificant. The disparity in measured interfacial areas between the two methods is attributed to the limitation of the microtomography method to characterize interfacial area associated with microscopic surface roughness due to resolution constraints.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
McDonald, K., K. C. Carroll, and M. L. Brusseau (2016), Comparison of fluid-fluid interfacial areas measured with X-ray microtomography and interfacial partitioning tracer tests for the same samples, Water Resour. Res., 52, 53935399.
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Progress 10/01/14 to 09/30/15
Outputs
Target Audience:Academia Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project provided training opportunities for two graduate students. How have the results been disseminated to communities of interest?Via publication in a journal article. What do you plan to do during the next reporting period to accomplish the goals?Conduct additional experiments to continue progression of the project.
Impacts
What was accomplished under these goals?
Interfacial partitioning tracer tests (IPTT) are used to measure air-water interfacial area for unsaturated porous media. The standard IPTT method involves conducting tests wherein an aqueous surfactant solution is introduced into a packed column under unsaturated flow conditions. Surfactant-induced drainage has been observed to occur for this method in some cases, which can complicate data analysis and impart uncertainty to the measured values. Two novel alternative approaches for conducting IPTTs are presented herein that are designed in part to prevent surfactant-induced drainage. The two methods are termed the dual-surfactant IPTT (IPTT-DS) and the residual-air IPTT (IPTT-RA). The two methods were used to measure air-water interfacial areas for two natural porous media. System monitoring during the tests revealed no measurable surfactant-induced drainage. The measured interfacial areas compared well to those obtained with the standard IPTT method conducted in such a manner that surfactant-induced drainage was prevented.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Brusseau, M.L., El Ouni, A., Araujo, J.B., Zhong, H. Novel Methods for Measuring Air-Water Interfacial Area in Unsaturated Porous Media. Chemosphere, 127, 208-213, 2015.
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Progress 10/01/13 to 09/30/14
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Two graduates students and one Post-Doc (not funded by this project) conducted experiments addressing the project goals. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals? Continue experiments and publication of manuscripts.
Impacts
What was accomplished under these goals?
Several sets of experiments addressing the goals have been conducted. Four manuscripts are in production, one is in review, and one is in press.
Publications
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