Low impact leaching agents as remediation media for organotin and metal contaminated sediments

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:282

Article

Noren, Anna¹  Fedje, Karin Karlfeldt^1,2  Stromvall, Ann-Margret¹  Rauch, Sebastien¹  Andersson-Skold, Yvonne^3,4 

[1] Chalmers Univ Technol, Dept Architecture & Civil Engn, Water Environm Technol, SE-41296 Gothenburg, Sweden

[2] Renova AB, Recycling & Waste Management, Box 156, SE-40122 Gothenburg, Sweden

[3] Swedish Natl Rd & Transport Res Inst VTI, Box 8072, SE-40278 Gothenburg, Sweden

[4] Chalmers Univ Technol, Dept Architecture & Civil Engn, Geol & Geotech, SE-41296 Gothenburg, Sweden

关键词: Tributyltin removal;    Metal extraction;    Sediment treatment;    Low environmental impact;    Contaminated sediment;    Sediment washing;   

DOI  :  10.1016/j.jenvman.2020.111906

来源: Elsevier

【 摘 要 】

All over the world, elevated levels of metals and the toxic compound tributyltin (TBT) and its degradation products are found in sediments, especially close to areas associated with shipping and anthropogenic activities. Ports require regular removal of sediments. As a result, large volumes of often contaminated sediments must be managed. The aim of this study was to investigate enhanced leaching as a treatment method for organotin (TBT) and metal (Cu and Zn) contaminated marine sediments. Thus, enabling the possibility to reuse these cleaner masses e. g. in construction. In addition to using acid and alkaline leaching agents that extract the OTs and metals but reduce the management options post treatment, innovative alternatives such as EDDS, hydroxypropyl cellulose, humic acid, iron colloids, ultra-pure Milli-Q water, saponified tall oil (soap), and NaCl were tested. Organotin removal ranged from 36 to 75%, where the most efficient leaching agent was Milli-Q water, which was also the leaching agent achieving the highest removal rate for TBT (46%), followed by soap (34%). The TBT reduction accomplished by Milli-Q water and soap leaching enabled a change in Swedish sediment classification from the highest class to the second highest class. The highest reduction of Zn was in HPC leached samples (39% removal) and Cu in EDDS leached samples (33% removal). Although high metal and OT leaching were achieved, none of the investigated leaching agents are sufficiently effective for the removal of both metals and OTs. The results of this study indicate that leaching with ultra-clean water, such as Milli-Q water, may be sufficient to treat TBT contaminated sediments and potentially allow mass reuse.

【 授权许可】

Free