検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年

圧縮成型ベントナイトの透水係数に及ぼすNaNO$$_{3}$$濃度の影響

Effect of the concentration of NaNO$$_{3}$$ solution on hydraulic conductivity of compacted bentonite

三原 守弘; 小林 一三*

Mihara, Morihiro; Kobayashi, Ichizo*

本研究では、圧縮成型ベントナイトの乾燥密度を1.8Mg/m$$^{3}$$として通液の硝酸ナトリウムの濃度を変化させて測定し、硝酸ナトリウム濃度が透水係数に及ぼす影響について実験的に調査を行った。通液の硝酸ナトリウムの濃度が高くなるに伴い圧縮成型ベントナイトの透水係数が大きくなった。透水係数の増加は、硝酸ナトリウム濃度が0$$sim$$2mol/Lまでは著しいが、2mol/Lを超えてもほとんど変化しなかった。高塩濃度においても、処分施設内の地下水の移動を抑制するための透水係数の性能目標値10$$^{-11}$$m/sを下回った。乾燥密度を大きくすると、透水係数の絶対値が小さくなるとともに、通液の塩濃度の影響を受けにくくなる。硝酸ナトリウム水溶液の濃度がベントナイトの透水係数に及ぼす影響のうち、硝酸ナトリウム水溶液の粘性の影響は小さいことが確認された。

In this study, the dependencies of hydraulic conductivity of the compacted bentonite of which a dry density was 1.8 Mg/m$$^{3}$$ on sodium nitrate concentration were investigated experimentally. The enhancement of hydraulic conductivity was observed using sodium nitrate solution of high concentration. The enhancement of 0$$sim$$2mol/L of the nitrate concentration was significant high. In the solution of $$>$$ 2mol/L nitrate, the hydraulic conductivities were hardly changed. The hydraulic conductivities using the sodium nitrate solution of high concentration, $$>$$ 2mol/L, were less than 10$$^{-11}$$m/s which was required value in the repository to restrict the ground water flow. It was more difficult that nitrate concentration of solution affects hydraulic conductivity of the highly compacted bentonite comparing with the lower compacted density bentonite. It was found that the effects of the viscosities of nitrate solution were small.

Access

:

- Accesses

InCites™

:

Altmetrics

:

[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.