Overview of Ex Situ Decontamination Techniques for Soil Cleanup

Abstract

The paper is a short review on the soil decontamination applying ex-situ techniques. Some sources and pathways of soil contamination are discussed. It was revealed that available techniques for soil decontamination can be divided in two parts, depending on where the action have place: in-situ or ex-situ. Also, depending on the nature of the process, these techniques can be biological, physical-chemical and thermal. In order to decontaminate soils properly, the primary contaminants (hydrocarbons such as petroleum residues, solvents, pesticides, herbicides, wood preservatives, heavy metals, munitions, which result from different industries and agricultural activities) have to be detected and analyzed. The main features of ex-situ soil decontamination are reviewed and also status of each technology, advantages, disadvantages, limitations, and contaminants treated, are included.

Ex-Situ Remediation Technologies for Environmental Pollutants: A Critical Perspective

“…Commercial incinerators are generally designed as closed burning rotary kilns that are equipped with an air pollution control system, a quench unit and an afterburner (Pavel and Gavrilescu 2008 ). Such incinerators are used to remediate soils that are contaminated with dioxins, PCBs, chlorinated hydrocarbons and explosives.…”

Examination of Three Different Organic Waste Biochars as Soil Amendment for Metal-Contaminated Agricultural Soils

“…immobilize heavy metals from soil (Mulligan et al 2001;Pavel and Gavrilescu 2008). Chemical immobilization methods that use soil amendments to reduce metal mobility and/or phytoavailability are one of the widely adapted technologies in remediation methods (Park et al 2011b).…”

Dual Soil Decontamination Procedures

“…However, such procedures may be valuable in diminishing or even completely eliminate a particular pollutant, but in the probable case of multiple contaminations it would mean a multiple treatment of the polluted soil. Moreover, most of these treatment methods are still on the laboratory or on the ex situ scale [11]. This renders most of the laboratory-scale treatment inapplicable because of ultimately high costs: the same soil should be treated in various ways, according to each particular pollutant present [12,13].…”

“…There are various ways to consider the most appropriate way to treat a contaminated soil [11]. These are the following: (1) doing nothing (if the environmental assessment indicates that humans and the environment are not at risk, then no remediation activity is required, e.g., in the case of small-scale spills on sites where human and animal exposure is not likely), (2) introducing institutional controls to contain the contaminants in the infected area (a legal or institutional mechanism that limits the use or the access to the contaminated area, e.g., the Chernobyl or Fukushima areas) or (3) the removal of soil and/or destruction of contaminants (in some cases, the best option may be to physically remove the contaminated soil and move it to a special treatment, storage and disposal facility in other cases, it is possible to remove the contaminant from the soil using technologies such as surfactant washing, soil washing or thermal desorption).…”