Evaluation of barrier materials for removing pollutants from groundwater rich in natural organic matter

Abstract

Permeable barriers are used for passive remediation of groundwater and can be constructed from a range of materials. The optimal material depends on the types of contaminants and physico-chemical parameters present at the site, as well as the hydraulic conductivity, environmental safety, availability, cost and long-term stability of the material itself. The aim of the presented study was to test a number of materials for their ability to remove heavy metals and organic pollutants from groundwater with a high (140 mg L(-1)) content of natural organic matter (NOM). The following materials were included in the study: sand, peat, fly ash, iron powder, lignin and combinations thereof. Polluted water was fed into glass columns loaded with each sorbent and the contaminant removal efficiency of the material was evaluated through chemical analysis of the percolate. Materials based on fly ash and zero-valent iron were found to be the most effective for heavy metal removal, while fly ash and peat were the most effective for removing aliphatic compounds. Filtration through lignin and peat led to leaching of NOM. Although the leaching decreased over time, it remained high throughout the experiments. The results indicate that remediation of contaminated land at disused industrial sites is a complex task that often requires the use of mixed materials or a minimum of two sequential barriers.

A Bibliometric Description of Lignin Applicability for the Removal of Chemical Pollutants in Effluents

“…Several other studies describe the use of lignin as a precursor material in the manufacture of nanoparticles (Li et al 2018b), lignin films (Duan et al 2018), spheres (Kwak et al 2016), microspheres (Li et al 2016), mesoporous material (Tang et al 2016), resins (Li et al 2015b) and permeable barriers (Kozyatnyk et al 2014) for the treatment of effluents containing toxic chemical agents.…”

Buffering Copper Tailings Acid Mine Drainage: Modeling and Testing at Fushë Arrëz Flotation Plant, Albania

“…When pyrite is exposed to water and oxygen, it transforms into dissolved iron, sulfate and hydrogen, increasing the acidity of the water [1][2][3]. The acid drainage from mines depends on the acid-producing (sulfide) and buffering (mainly from natural such as carbonates to constructed such as permeable barriers of various materials [4,5]) minerals exposed to the atmosphere.…”

Guidelines for Preliminary Design of Funnel-and-Gate Reactive Barriers

“…However, the design of such PRBs relies on three technical aspects: (a) the reactive media must be appropriate to the pollutants, (b) the filters' size must be large enough to ensure a sufficient residence time [9][10][11], and (c) the reactive material must have a sufficient hydraulic conductivity to prevent any bypass of the system. The first aspect is a key issue in the design of PRBs and a particular attention has to be dedicated to the selection of the reactive or sorbent material when installing any PRB system [12]. The present paper will consider that the reactive media is selected adequately and the compatibility with the contaminant is not an issue.…”