Desorption and Co-Dissolution of Uranium-Bearing Solids During Alkalinity-Enhanced Flushing of Contaminated Sediments

IF 1.8 4区 环境科学与生态学 Q3 WATER RESOURCES
Martin Dangelmayr, Cullen Meurer, Aaron Tigar, Raymond H. Johnson, Charles Paradis
{"title":"Desorption and Co-Dissolution of Uranium-Bearing Solids During Alkalinity-Enhanced Flushing of Contaminated Sediments","authors":"Martin Dangelmayr,&nbsp;Cullen Meurer,&nbsp;Aaron Tigar,&nbsp;Raymond H. Johnson,&nbsp;Charles Paradis","doi":"10.1111/gwmr.12573","DOIUrl":null,"url":null,"abstract":"<p>Elevated uranium concentrations in groundwater remain a persistent challenge at contaminated sites. Several sites rely on natural flushing of uranium as a remediation strategy. Uncertainties in conceptual models can cause remediation strategies to underestimate timeframes required to reach remediation goals. In this study, laboratory experiments were conducted to investigate uranium flushing of sediments from a site with persistent groundwater contamination. Six columns were used to simulate alkalinity-enhanced flushing of uranium from sediments, by switching influent alkalinity after ~12 pore volumes. About 20% to 31% of sediment uranium was consistently flushed from the sediments. <i>K</i><sub>d</sub> values varied greatly (5.3 to 117 L/kg) but were consistently lower (20% to 50%) during influents with elevated alkalinity. The mass of uranium recovered from the columns also was consistently higher (5% to 80%) during alkalinity-enhanced flushing periods. However, column experiments with sequentially increasing alkalinity showed diminishing returns in uranium elution at higher carbonate concentrations. The loss of flushing efficiency is attributed to significant calcite precipitation at higher alkalinities. The results show that alkalinity-enhanced flushing of uranium could be employed as a viable remediation scheme if calcite precipitation could be minimized in a field application.</p>","PeriodicalId":55081,"journal":{"name":"Ground Water Monitoring and Remediation","volume":"43 2","pages":"61-76"},"PeriodicalIF":1.8000,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ground Water Monitoring and Remediation","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/gwmr.12573","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"WATER RESOURCES","Score":null,"Total":0}
引用次数: 0

Abstract

Elevated uranium concentrations in groundwater remain a persistent challenge at contaminated sites. Several sites rely on natural flushing of uranium as a remediation strategy. Uncertainties in conceptual models can cause remediation strategies to underestimate timeframes required to reach remediation goals. In this study, laboratory experiments were conducted to investigate uranium flushing of sediments from a site with persistent groundwater contamination. Six columns were used to simulate alkalinity-enhanced flushing of uranium from sediments, by switching influent alkalinity after ~12 pore volumes. About 20% to 31% of sediment uranium was consistently flushed from the sediments. Kd values varied greatly (5.3 to 117 L/kg) but were consistently lower (20% to 50%) during influents with elevated alkalinity. The mass of uranium recovered from the columns also was consistently higher (5% to 80%) during alkalinity-enhanced flushing periods. However, column experiments with sequentially increasing alkalinity showed diminishing returns in uranium elution at higher carbonate concentrations. The loss of flushing efficiency is attributed to significant calcite precipitation at higher alkalinities. The results show that alkalinity-enhanced flushing of uranium could be employed as a viable remediation scheme if calcite precipitation could be minimized in a field application.

碱性强化冲洗污染沉积物过程中含铀固体的解吸和共溶
在受污染地区,地下水中铀浓度的升高仍然是一个持续的挑战。一些地点依靠自然冲洗铀作为补救策略。概念模型中的不确定性可能导致补救策略低估达到补救目标所需的时间框架。在这项研究中,进行了实验室实验,以调查地下水持续污染场地沉积物的铀冲洗。通过在~12个孔隙体积后切换进水碱度,使用六个柱模拟沉积物中铀的碱度增强冲洗。大约20%至31%的沉积物铀一直从沉积物中被冲走。Kd值变化很大(5.3至117 L/kg),但在碱度升高的影响期间始终较低(20%-50%)。在碱度增强的冲洗期间,从柱中回收的铀的质量也一直较高(5%-80%)。然而,碱度顺序增加的柱实验表明,在较高的碳酸盐浓度下,铀洗脱的回报率递减。冲洗效率的损失归因于较高碱度下的大量方解石沉淀。结果表明,如果在现场应用中能够最大限度地减少方解石沉淀,那么碱度增强的铀冲洗可以作为一种可行的修复方案。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
CiteScore
3.30
自引率
10.50%
发文量
60
审稿时长
>36 weeks
期刊介绍: Since its inception in 1981, Groundwater Monitoring & Remediation® has been a resource for researchers and practitioners in the field. It is a quarterly journal that offers the best in application oriented, peer-reviewed papers together with insightful articles from the practitioner''s perspective. Each issue features papers containing cutting-edge information on treatment technology, columns by industry experts, news briefs, and equipment news. GWMR plays a unique role in advancing the practice of the groundwater monitoring and remediation field by providing forward-thinking research with practical solutions.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信