Development and modeling of sediment volume reduction based on ion exchange reaction

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04620
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22040:Hydroengineering-related
• Research Institution: Hiroshima University
• Principal Investigator: Nakashita Shinya 広島大学, 先進理工系科学研究科(工), 助教 (90613034)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 堆積泥 / 保水性 / イオン交換 / 陽イオン交換容量 / 有機物含有量 / 示差熱分析

Outline of Final Research Achievements

We established a method to exchange to adsorbed cation on the sediment to monovalent cations, which have lower water retention properties. To investigate the amount of cation adsorption sites in sedimentary mud, we combined a method using a 0.1 mol/L barium chloride solution, which is used in the field of geotechnical engineering, with a 1 mol/L ammonium acetate solution, which is used in the fields of agricultural engineering and soil science. As a result, it was found that the amount of adsorption sites of functional groups of organic matters and the amount of adsorption sites on the surface and between layers of clay minerals can be estimated. It was also suggested that it may be possible to estimate the substances contained in sediment by changing the measurement conditions of differential thermogravimetric analysis.

Free Research Field

海岸工学

Academic Significance and Societal Importance of the Research Achievements

これまで粘土鉱物に対して吸着イオンを交換した場合の凝集性の変化について検討した研究例は存在したが，粘土鉱物に有機物が付着した複雑な特性を持つ堆積泥を対象として電気化学的な効果を検討した研究は無かった．本研究では，堆積泥に吸着するイオンの種類や量を変化させることで泥の減容化が可能であることを明らかにした．また，吸着陽イオン量を決定する大きな要因である堆積泥に含まれる有機物の種類や量を示差熱重量分析を用いて検討する手法を提案した．