Study on insolubilization treatment by neutralization of acid sediment containing natural arsenic

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K06566
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: Kyushu Sangyo University
• Principal Investigator: HAYASHI Yasuhiro 九州産業大学, 建築都市工学部, 教授 (50274692)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 酸性土 / 中性化処理 / 有効利用 / pH / 酸性化可能性試験 / 乾湿繰返し養生

Outline of Final Research Achievements

The neutralization treatment for the effective use of acidified soil as a geomaterial was studied. The following results were obtained. In case of calcium carbonate is added for neutralization, there are advantages such as low risk of becoming highly alkaline due to excessive addition and little change over the long term, but there is a concern that the amount added will increase. In case of magnesium oxide was added, neutralization could be achieved in the short term with a small amount, but there was a concern that the pH would become too high. In order to evaluate long-term pH in a short period, it is desirable to measure the pH by acidification test, using a sample that has been subjected to repeated dry and wet curing.

Free Research Field

地盤工学

Academic Significance and Societal Importance of the Research Achievements

首都圏の建設工事は工事規模が大きいうえ，大深度地盤の掘削によって，酸化し酸性化する土砂が大量に発生する。この土砂を利用可能な状態に改良し，発生現場に近い場所で有効に活用することで，天然土砂の採掘を抑制するとともに，残土の処分が提言されるため処分場容量の保全が可能であるうえ，土砂運搬に伴う環境負荷の低減に貢献することができる。