Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

A (Atmospheric and Hydrospheric Sciences) » A-GE Geological & Soil Environment

[A-GE30] Energy-Environment-Water Nexus and Sustainable Development

Mon. May 21, 2018 9:00 AM - 10:30 AM 104 (1F International Conference Hall, Makuhari Messe)

convener:Ming Zhang(Institute for Geo-Resources and Environment, Geological Survey of Japan, AIST), Ken Kawamoto(Graduate School of Science and Engineering, Saitama University), Xue Qiang(中国科学院武漢岩土力学研究所, 共同), Jet-Chau Wen(National Yunlin University), Chairperson:Zhang Ming(AIST), Saito Hirotaka(Tokyo University of Agriculture and Technology)

9:55 AM - 10:10 AM

[AGE30-04] Determining Diffusive Parameters of Contaminants out of Geo-Materials through Out-Diffusion Experiments

*Ranran Song1, Ming Zhang2, Chihiro Inoue1 (1.Graduate School of Environmental Studies, Tohoku University, 2.Geological Survey of Japan, AIST)

Keywords:mass transport, diffusion, out-diffusion experiment, contaminants, heavy metal, lead

Diffusion through and sorption onto a geo-material are prominent mechanisms associated with mass transport within it when groundwater flow is very low. Several laboratory diffusion test methods have been available and have been applied to evaluate effective coefficient and capacity factor. Conventional laboratory diffusion tests are generally laborious and time consuming and some methods need to slice test specimens. This study focuses on the process that heavy metals, such as lead (Pb), diffuse out of geo-materials. To establish an out-diffusion experiment method, a theoretical solution was derived based on the linear sorption model. Parameter studies were then performed to understand the effects of each parameter on experimental duration. To shorten the time required for a diffusion test, a relative large diameter specimen and a relative small reservoir volume should be adopted which can enlarge mass exchange areas and make concentration of a targeted element in the reservoir vary rapidly. Theoretically, the length of a specimen does not affect the time required for an experiment. Sampling with different frequency may induce experimental errors. A series of experiments were conducted to verify this out-diffusion test method and to study lead diffusion out of a sandstone.