JpGU-AGU Joint Meeting 2017

講演情報

[EE] ポスター発表

セッション記号 A (大気水圏科学) » A-GE 地質環境・土壌環境

[A-GE40] [EE] エネルギ・環境・水ネクサスと持続的発展

2017年5月22日(月) 10:45 〜 12:15 ポスター会場 (国際展示場 7ホール)

コンビーナ:張 銘(産業技術総合研究所地質調査総合センター地圏資源環境研究部門)、薛 強(中国科学院武漢岩土力学研究所)、温 志超(国立曇林科技大学)、川本 健(埼玉大学大学院理工学研究科)

[AGE40-P03] The role of transients in ionic strength in colloid remobilization in saturated porous media

*Qiulan Zhang1 (1.China University of Geosciences-Beijing)

キーワード:transients in ionic strength, colloid remobilization, saturated steady-state flow

The deposition and remobilization of soil colloids in groundwater are important with respect to the environmental fate of contaminants and the remediation of subsurface contamination. We conducted a series of column experiments to investigate the effect of solution ionic strength on colloid transport and remobilization. In the experiment, model colloids-Polystyrene latex microspheres with diameter of 1μm were employed, quartz sand packed column was used as porous medium. During the experiment, ionic strength was changed from 50mM to 10mM, 60mM to 20mM, 70mM to 30mM, then to ultrapure water, or reduced from 50mM, 60mM , 70mM to ultrapure water directly.
We found that colloid remobilization occur under the condition of transients in ionic strength. When ionic strength was 50mM, 3.88% percent of the attached colloid was remobilized after it changed to 10mM. When ionic strength was 60mM, 0.71% percent of the attached colloid was remobilized after it changed to 20mM. When ionic strength was 70mM, 0.07% percent of the attached colloid was remobilized after it changed to 30mM. When ionic strength was reduced from 60mM to 10mM, 20mM, 30mM respectively, the corresponding remobilization rate was 1.75%, 0.71%, 0.09%, the total remobilization rate was 52.12%, 50.86%, 42.73% respectively after injecting to ultrapure water.
We concluded that the amount of colloid remobilization was related to the magnitude of the change in ionic strength.