Evaluating a novel permeable reactive bio-barrier to remediate PAH-contaminated groundwater

Abstract

Permeable reactive barriers (PRBs) are an environmentally-friendly, cost-effective insitu technology that can be used to remediate polycyclic aromatic hydrocarbons (PAHs)-contaminated groundwater. In this study, PRB of two various materials (A and B) that relied on microbes self-domestication mechanism were designed and tested. The materials A and B were the same apart from their carbon source: A was based on wheat straw and B was based on coconut shell biochar. We used laboratory batch experiments followed by long-term column tests to assess the capacity of these two materials to remediate PAHs. The results showed that both A and B removed almost 100% of the phenanthrene. More carbon was released from A (80-500 mg/L) than from B (72-195 mg/L), and slightly more oxygen was released from B (7.31-10.31 mg/L) than A (7.15-9.64 mg/L). The release of organic carbon from material B was more stable than that from material A. The bacterial communities of both columns comprised members of the Mycobacterium, Pseudomonas, and Sphingomonas genera that are known to degrade phenanthrene, and Pseudomonas and Sphingomonas were 7 times more abundant in column B than in column A. Material B is more promising for treating PAH-contaminated groundwater than material A.

Microbe–Mineral Interaction-Induced Microorganism-Augmented Permeable Reactive Barriers for Remediation of Contaminated Soil and Groundwater: A Review

“…Coconut shell biochar pellets (coconut shell biochar combined with diatomite, attapulgite, and CaO 2 ) were used to construct Bio-PRBs for the treatment of PHE-contaminated groundwater . Compared to that of wheat straw pellet Bio-PRBs (0.013 mg g –1 ), the PHE adsorption capacity (0.035 mg g –1 ) increased by 169% in coconut shell biochar Bio-PRBs . The biochar-immobilized microorganism and ZVI gel beads were developed to construct Bio-PRBs for the treatment of 2,4,6-TCP-contaminated groundwater .…”

Remediation of soil and groundwater contaminated with organic chemicals using stabilized nanoparticles: Lessons from the past two decades

“…Other than ZVI, many other materials have been tested for in situ remediation of groundwater contaminated with halogenated organics, phenolic compounds, pharmaceuticals, and nitroaromatics (Guan et al, 2015). For instance, zeolite (Vignola et al, 2011), calcite (Turner et al, 2008), pyrite (Wang et al, 2020), combined calcium peroxide and straw/biochar (Liu et al 2019) have been used or tested as PRB filling materials. In addition, biochar (Tang et al, 2013), mackinawite (FeS) (Jeong and Hayes, 2007;Duan et al, 2019b), FeS-modified ZVI (Duan et al, 2019a;Kim et al, 2011;, and MnO 2activated persulfate (Mazloomi et al, 2016) have been tested to remediate soil and groundwater contaminated with organic pollutants.…”

A novel permeable reactive biobarrier for ortho-nitrochlorobenzene pollution control in groundwater: Experimental evaluation and kinetic modelling

“…Yin et al (2012) reported that the presence of certain organic substrates improved the removal rate of p-NCB with microbes by promoting a bio-reduction process. In a previous study, our group accessed the potential of wheat straw as an additional carbon source for the remediation of groundwater contaminated with phenanthrene (Liu et al, 2019). As a continuation of that prior work, the present research examined the role of wheat straw as a carbon and energy source to promote the biological reductive dechlorination of o-NCB.…”