EAPSI:Evaluating the Performance of Energy By-Products in Cement-Based Waste Forms and Barriers Pertinent to China and the United States

世界各国在妥善管理废物方面持续存在挑战。 本研究旨在描述中国和美国相关的水泥基废物形式、废物屏障和混凝土产品中所含的各种能源副产品，以预测材料的耐久性、污染物保留和环境安全性。 这项研究将与中国上海同济大学废物管理领域的领先专家何品晶教授及其研究团队合作进行。 通过吸收不同国家的废物管理知识和经验，可以为复杂的废物形式和障碍开发更有效的实验技术和改进的材料特性。 本研究的结果将用于支持两国废物管理的改进决策工具，并促进这些材料的有益再利用，从而减少材料生产和原材料开采的二氧化碳足迹，同时确保环境安全。降解和非降解废物形式，用作辅助胶凝材料的二次材料，和混凝土含有这些二次材料将进行分析，以提高物理化学微观结构的理解，使用各种先进的显微镜技术，包括扫描电子显微镜与能量色散光谱（SEM-EDS），同步辐射的微x射线荧光和微x射线衍射，和扫描透射电子显微镜结合能量色散光谱。 具体而言，将研究SEM-EDS中光束相互作用体积的影响，以更好地了解这种类型的异质和复杂的废物形式和障碍物分析的局限性。 首先分析均匀的纯元素，然后分析更复杂的相，包括氧化物，矿物质，废物形式和障碍物，研究粒度和相组成的影响。 将开发算法，以说明材料分析中的光束相互作用体积的影响。 这些结果将用于帮助表征废物形式和屏障的复杂性，利用SEM-EDS改进材料分析，并更好地了解可能影响这些材料长期性能的碳化和氧化等降解机制。这个NSF EAPSI奖是与中国科技部合作资助的。

There are persistent challenges to properly managing waste in countries throughout the world. This study aims to characterize a wide variety of energy by-products contained in cement-based waste forms, waste barriers and concrete products pertinent to China and the United States in order to predict material durability, contaminant retention and environmental safety. This research will be conducted in collaboration with Professor Pin-Jing He, a leading expert in waste management, and his research team at Tongji University in Shanghai, China. By assimilating the knowledge of waste management from different countries and experiences, more efficient experimental techniques and improved material characterization can be developed for complex waste forms and barriers. Results from this study will be implemented to support improved decision making tools for waste management across both countries and to promote beneficial reuse of these materials which can reduce the carbon dioxide footprint for material production and the mining of raw materials while ensuring environmental safety.Degraded and non-degraded waste forms, secondary materials used as supplemental cementitious materials, and concretes containing these secondary materials will be analyzed to improve understanding of the physical-chemical microstructure using a variety of advanced microscopy techniques including scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), synchrotron radiation for micro x-ray fluorescence and micro-x-ray diffraction, and scanning transmission electron microscopy coupled with energy dispersive spectroscopy. Specifically, the impact of the beam interaction volume in SEM-EDS will be investigated to better understand the limitations of this type of analysis for heterogeneous and complex waste forms and barriers. The effect of particle size and phase composition will be investigated by first analyzing uniform pure elements and then by analyzing more complex phases including oxides, minerals, and the waste forms and barriers. Algorithms will be developed to account for the effect of the beam interaction volume on material analysis. These results will be used to help characterize the complexity of the waste forms and barriers, improve material analysis utilizing SEM-EDS, and to better understand the degradation mechanisms such as carbonation and oxidation which can impact the long-term performance of these materials. This NSF EAPSI award was funded in collaboration with the Ministry of Science and Technology of China.