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Bioremediation for Sustainable Environmental Cleanup

Table 2.4. In-situ bioprecipitation case-studies.

Method

Location

Project Specifications

Method Efficacy

References

Reactive

Barrier

Curilo mine district,

Sophia

Microorganism:

SRB

Electron Donor: Leaves,

compost, zero-valent iron,

silica sand, perlite, limestone

25% SO4

2–

6% Cd

*Percentages are

higher with sorption

consideration

Pagnanelli et al. 2009

Synthetic

groundwater using

contaminated

sediment from

Belgium

Microorganism:

SRB

Electron Donor: Zero-valent

iron

47% As

Kumar et al. 2016

Nickel Rim tailings

impoundment

Microorganism:

SRB

Electron Donor: Compost,

leaf mulch, wood chips

74% SO4

2–

>85% Fe

Benner et al. 1999

Unknown

Microorganism:

SRB

Electron Donor: Composted

leaf mulch, wood chips,

sawdust, sewage sludge

98% SO4

2–

26.67-99.99% Fe

75–99.17% Zn

98.75–99.92% Ni

Waybrant et al. 2002

Wetlands

Camborne,

Cornwall

Microorganism:

SRB

Electron Donor: Sodium

acetate, propionic acid,

glycerol

3.1 and 4.0 µmol • l^–1 •

h^–1 Fe

1.31 and 2.44 µmol • l^–1

• h^–1 Zn

Webb et al. 1998

Injection

Wells

The Netherlands

Microorganism:

SRB

Electron Donor: Molasses

99.98% Zn

Janssen and

Temminghoff 2004

Laboratory tests for

Umicore sites

Microorganism:

SRB

Electron Donor: Lactate,

cheese whey, soy oil

> 99% Zn

> 99% Co

> 85% SO4

2­

Vanbroekhoven et al.

2008

Metal processing

factory in

Maasmechelen,

Belgium

Microorganism:

SRB

Electron Donor: Lactate,

glycerol, vegetable oil

96%–97% Zn

Lookman et al. 2013

metal(loid) contaminated plume, whereby the reactive barrier is designed to degrade or immobilize

the contaminant via BSR. The two primary configurations of a reactive barrier are continuous

(vertical barrier, perpendicular to the contaminant plume) and funnel-and-gate system (V-shaped

funnel directing contaminant plume through the vertical reactive gate) (Sharma and Reddy 2004).

The reactive barrier is designed for the specific site, such that reactive material (electron donor and

microorganism consortium) is selected based on the desired type of bioprecipitation. Acid Mine

Drainage (AMD) for example, which is highly acidic and heavily contaminated with sulfuric acid

(SO4

2– and H+) and other heavy metals, could use a layered mixture of silica sand, organic waste

and silica sand either in a horizontal or vertical sequence to decrease effluent AMD (Benner et al.

1999, Waybrant et al. 2002). Clogging of reactive material due to bioprecipitation may decrease the

efficacy of the barrier over time (Kiran et al. 2017).

Wetlands and engineered wetlands aim to remove metal(loid) contaminants from water with

degradation and bioprecipitation techniques. They can be in the form of aerobic wetlands, anaerobic

wetlands (Johnson and Santos 2020) or anoxic ponds (Kiran et al. 2017). There are two main

impacts to the redox potential of these designs: the hydraulic design and the mode of operation. The

hydraulic designs can use a vertical flow (aerobic) treatment, horizontal subsurface flow (anoxic)