[A-GE31] 地質媒体における物質移動，物質循環と環境評価

[AGE31-P10] 気泡数密度およびイオン強度が飽和多孔質内のナノバブル挙動に与える影響

江尻 哲英¹、*濱本 昌一郎¹、ダン トゥエット¹、二瓶 直登¹、西村 拓¹ (1.東京大学大学院農学生命科学研究科)

キーワード：ナノバブル、輸送、多孔質体、イオン強度、気泡数密度

An understanding of nano-scale bubble (NB) transport in porous media is important for potential application of NBs in soil/groundwater remediation. It is expected that the physical properties and solution chemistry of NB water highly influences the surface characteristics of NBs and porous media and the interaction between them, thus affecting the transport characteristics of NB. In this study, one-dimensional column transport experiments using glass beads were conducted, where air-NBs water were injected to the column. The turbidity, pH, EC, DO, and bubble size distribution in the effluent were measured. Effects of bubble concentration and ionic strength on the NBs transport were investigated based on the column experiments. The results showed that relative turbidities (measured turbidity in the effluents / turbidity in the applied NBs water) during the NBs water injection were lower for NBs water at lower bubble concentration. In addition, with increasing ionic strength in NBs water, lower relative turbidities in the effluents were observed, suggesting reduced repulsive force between NBs and glass beads surface. For NBs water at the same ionic strength, NBs water containing Na⁺ showed higher NBs mobility as compared to one containing Ca²⁺. Thus, ion species also influenced NBs transport characteristics.