EAGER: Deterioration of Stormwater Filter Media by Deicing Salts: X-ray Micro Computed Tomography (µCT)

1548901 Kakuturu本项目提出了一种创新的X射线微型计算机断层扫描技术，以研究除冰盐对雨水滤料的影响。雨水过滤器在防止洪水和保护环境方面至关重要，因为它允许雨水渗入地面并将污染物困住。先前的研究已经提出了对除冰盐在雨水过滤介质恶化和环境污染中的作用的担忧。该项目概述了一项利用氯化钠作为除冰盐进行流动试验的计划，并利用X射线微计算机层析成像技术对雨水滤料加盐前后的孔结构进行评价。这些数据将使用计算机模拟进行分析，以加深对恶化的理解，这是一项关键的研究需要。有两个假设需要检验：(1)“流量”和“有效孔隙度与总孔隙度”之间存在统计相关性。(2)在氯化钠总量相似的情况下，雨水滤料降解的差异(“有效孔隙度”与“总孔隙度”的比率)在三种不同的氯化钠浓度下不会有显著差异。这项研究的结果将解决两个科学问题：(1)施加氯化钠会如何改变SFM的孔结构？(2)“有效孔隙度与总孔隙度的比率”与入渗率之间是否存在关系？该项目的目标是探索和测试这一截然不同的研究方法，以满足科学了解雨水滤料劣化的迫切需要。PI建议通过使用最先进的X射线微计算机层析成像以及离散元素和格子Boltzmann方法的组合模拟来实现这一目标。这种方法在其他研究领域也取得了成功，如医学、生物学、农业、地质学、工业等。该研究所成功地进行了一项利用X射线微计算机层析成像技术可视化SFMS孔结构的初步研究。同样的样本将在加盐前后进行扫描。三维图像数据将用于构建雨水滤料的三维孔隙结构。三维孔隙空间将用于形态分析和模型模拟。结果(孔隙度、梯度等的分布)这将有助于我们理解SFM恶化的机制。该项目将使X射线微计算机层析成像成为研究多孔介质的一种合适方法，并将改变人们对不同多孔介质的科学认识。

1548901KakuturuThis project proposes to explore an innovative use of x-ray micro computed tomography to investigate the effect of deicing salt on stormwater filter media. Stormwater filters are critical in preventing floods and protecting the environment by allowing stormwater to infiltrate to ground and entrapping the pollutants. Prior studies have raised concerns about the deicing salts' role in deterioration of stormwater filter media and environmental contamination. This project outlines a plan to conduct flow tests, using NaCl as a deicing salt, and to evaluate the pre- and post-salt-application pore structures' in stormwater filter media using x-ray micro computed tomography.This project will explore x-ray micro computed tomography to examine stormwater filter media pore structure. The data will be analyzed using computer simulations for developing an understanding of deterioration, a critical research need. Two hypotheses are to be tested: (1) There is a statistical correlation between "flow rate" and "ratio of active porosity to total porosity." (2) Given that the total amount of NaCl is similar, differences in stormwater filter media degradation (the ratio of "active porosity" to "total porosity") will not be significantly different at three different NaCl concentrations. The results of this research will address two scientific questions: (1) How does the pore structure of a SFM change due to application of NaCl? (2) Is there a relationship between the "ratio of active porosity to total porosity" and infiltration rate? This project's goal is to explore and test this radically different research approach for addressing the critical need to scientifically understand the deterioration of stormwater filter media. The PI proposes to achieve this goal by using state-of-the-art of x-ray micro computed tomography, and a combination of discrete element and lattice Boltzmann methods simulations. This approach has demonstrated success in other research fields, for example, medicine, biology, agriculture, geology, industrial, etc. The PI has successfully conducted a pilot study using x-ray micro computed tomography for visualization of SFMs' pore structure. The same samples will be scanned before and after salt application. The three dimensional image data will be used for constructing three dimensional pore structures of stormwater filter media. The three dimensional pore spaces will be used in morphological analysis and model simulations. Results (distribution of porosity, gradients, etc.) will help us in understanding the mechanism of SFM deterioration. This project will establish x-ray micro computed tomography as a suitable method for studying porous media, and will transform the scientific understanding of different porous media.