TY - JOUR
T1 - Sustainable stabilization/solidification of arsenic-containing soil by blast slag and cement blends
AU - Li, Jiang shan
AU - Chen, Liang
AU - Zhan, Baojian
AU - Wang, Lei
AU - Poon, Chi Sun
AU - Tsang, Daniel C.W.
N1 - Funding Information:
The authors appreciate the financial support from the Hong Kong Research Grants Council ( PolyU 15223517 ) and National Natural Science Foundation of China /Hong Kong Research Grants Council Joint Research Scheme ( N_PolyU511/18 , 51861165104 ) for this study.
Publisher Copyright:
© 2021 Elsevier Ltd
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/5
Y1 - 2021/5
N2 - Arsenic (As) is a naturally occurring trace element that may pose a threat to human health and the ecosystem, while effective remediation and sustainable reuse of As-containing soil is a challenge. This study investigated the geoenvironmental characteristics of a geogenic As-rich soil, and green binders (ground granulated blast slag (GGBS) and cement blends) were employed for the stabilization/solidification (S/S) of the soil under field-relevant conditions. Results indicate that the use of 10% binder could effectively immobilize As and chemical stabilization/physical encapsulation jointly determined the leaching characteristics of the S/S soils. The geogenic As could be effectively immobilized at the pH range of 5.5–6.5. The increasing use of GGBS enhanced the strength of the 28-d cured S/S soils because of long-term pozzolanic reaction, but also slightly improved the As leachability. Besides, the moisture content of the contaminated soils should be suitably adjusted to allow for desirable compaction of S/S soils, which resulted in high compressive strength and low of As leachability. Results show that soil moisture content of 20% was the most appropriate, which resulted in the highest strength and relatively lower As leaching. In summary, this study presents a sustainable S/S binder for recycling As-contaminated soil by using a combination of cement and GGBS.
AB - Arsenic (As) is a naturally occurring trace element that may pose a threat to human health and the ecosystem, while effective remediation and sustainable reuse of As-containing soil is a challenge. This study investigated the geoenvironmental characteristics of a geogenic As-rich soil, and green binders (ground granulated blast slag (GGBS) and cement blends) were employed for the stabilization/solidification (S/S) of the soil under field-relevant conditions. Results indicate that the use of 10% binder could effectively immobilize As and chemical stabilization/physical encapsulation jointly determined the leaching characteristics of the S/S soils. The geogenic As could be effectively immobilized at the pH range of 5.5–6.5. The increasing use of GGBS enhanced the strength of the 28-d cured S/S soils because of long-term pozzolanic reaction, but also slightly improved the As leachability. Besides, the moisture content of the contaminated soils should be suitably adjusted to allow for desirable compaction of S/S soils, which resulted in high compressive strength and low of As leachability. Results show that soil moisture content of 20% was the most appropriate, which resulted in the highest strength and relatively lower As leaching. In summary, this study presents a sustainable S/S binder for recycling As-contaminated soil by using a combination of cement and GGBS.
KW - Arsenic immobilization
KW - Green and sustainable remediation
KW - Low-carbon binders
KW - Soil remediation and recycling
KW - Stabilization/solidification
UR - http://www.scopus.com/inward/record.url?scp=85100617801&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2021.129868
DO - 10.1016/j.chemosphere.2021.129868
M3 - Journal article
AN - SCOPUS:85100617801
SN - 0045-6535
VL - 271
JO - Chemosphere
JF - Chemosphere
M1 - 129868
ER -