Hydraulic conductivity of soil-bentonite backfill comprised of SHMP-amended Ca-bentonite to Cr(VI)-impacted groundwater

doi:10.1016/j.jconhyd.2021.103856

	Hydraulic conductivity of soil-bentonite backfill comprised of SHMP-amended Ca-bentonite to Cr(VI)-impacted groundwater
	Yang, Yuling 5; Reddy, Krishna R.4; Zhan, Hongbin 3; Fan, Ridong 2; Liu, Songyu 5; Xue, Qiang 1; Du, Yanjun 5
刊名	JOURNAL OF CONTAMINANT HYDROLOGY
	2021-10-01
卷号	242 页码:8
关键词	Bentonite Heavy metal Hydraulic conductivity Slurry trench wall Contaminated groundwater
ISSN号	0169-7722
DOI	10.1016/j.jconhyd.2021.103856
英文摘要	Hexavalent chromium (Cr(VI)) in groundwater impose serious health problems for human society. This study investigates the potential of using calcium (Ca) bentonite amended with sodium hexametaphosphate (SHMP) as a backfill constituent material in the soil-bentonite slurry trench wall to envelop the Cr(VI) impacted groundwater. The hydraulic conductivity (K) and consolidation of backfill comprising of 80 wt% sand and 20 wt% SHMP-amended Ca-bentonite were determined via flexible-wall permeameter tests and oedometer tests, respectively. Microstructure characterizations of the amended bentonites before and after contamination were also explored. The results indicated that when the permeated liquid changed from tap water to Cr(VI) solution, the tested specimens exhibited a 1.0 to 1.2-fold variation in short-term K, with all K values fall in range of 2.1 x 10(-10) to 2.5 x 10(-10) m/s. This mild variation may be attributed to terminate the tests without achieving chemical equilibrium. On the other hand, the Cr(VI) solution had insignificant effect on consolidation of the amended backfill, which is attributed to the dominated incompressible sand matrix skeleton in the backfill that withstood the consolidation pressure and shield the negative effects of the contaminated solution. The microstructure images revealed that the Cr(VI) resulted in relatively strong interlink between particles. Overall, the SHMP-amended bentonite is promising for enhancing Cr(VI) containment performance of the soil-bentonite slurry trench wall backfills.
资助项目	National Natural Science Foundation of Chian[41907248] ; National Natural Science Foundation of Chian[41877248] ; National Primary Research & Development Plan of China[2019YFC1806000] ; National Primary Research & Development Plan of China[2018YFC1803100] ; National Primary Research & Development Plan of China[2018YFC1802300]
WOS研究方向	Environmental Sciences & Ecology ; Geology ; Water Resources
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000702805800010
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/28526]
专题	中科院武汉岩土力学所
通讯作者	Yang, Yuling; Du, Yanjun
作者单位	1.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China 2.Donghua Univ, Coll Environm Sci & Engn, Shanghai 201620, Peoples R China 3.Texas A&M Univ, Dept Geol & Geophys, College Stn, TX 77843 USA 4.Univ Illinois, Dept Civil & Mat Engn, Chicago, IL 60607 USA 5.Southeast Univ, Inst Geotech Engn, Jiangsu Key Lab Urban Underground Engn & Environm, Nanjing 210096, Peoples R China
推荐引用方式 GB/T 7714	Yang, Yuling,Reddy, Krishna R.,Zhan, Hongbin,et al. Hydraulic conductivity of soil-bentonite backfill comprised of SHMP-amended Ca-bentonite to Cr(VI)-impacted groundwater[J]. JOURNAL OF CONTAMINANT HYDROLOGY,2021,242:8.
APA	Yang, Yuling.,Reddy, Krishna R..,Zhan, Hongbin.,Fan, Ridong.,Liu, Songyu.,...&Du, Yanjun.(2021).Hydraulic conductivity of soil-bentonite backfill comprised of SHMP-amended Ca-bentonite to Cr(VI)-impacted groundwater.JOURNAL OF CONTAMINANT HYDROLOGY,242,8.
MLA	Yang, Yuling,et al."Hydraulic conductivity of soil-bentonite backfill comprised of SHMP-amended Ca-bentonite to Cr(VI)-impacted groundwater".JOURNAL OF CONTAMINANT HYDROLOGY 242(2021):8.