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remediation is aerobic and is most effective in cleaning larger areas. Microbes
acts as catalysts and minimize toxicity to humans by reducing the levels of toxic
contaminants in the soil.
6.1.2 Remediation Ex Situ
The soil excavated or pumped from the site is treated to remove contaminants by ex
situ bioremediation. Because this technique removes the soil before treatment,
faster decontamination of soils and the ability to treat a wide range of toxins in soils
with easier manageability are its main advantages.
6.1.3 Slurry-Phase Technique
As the name implies, a slurry is prepared by using a bioreactor to mix the contaminated soil with water and various reagents. Harmful substances present in the soil
will contact the microorganisms by homogenization. Thereafter, oxygen and supplements are introduced to the slurry, blended to create an ideal environment for the
microorganisms to break down the contaminants. The soil is tested when separation
of water is complete, and thereafter supplanted in that location with naturally existing microflora. A faster rate of bioremediation is its advantage.
6.1.4 Solid-Phase Technique
Bioremediation by the solid-phase process treats a contaminated soil by digestion in
aboveground reactors. Anaerobic conditions inside the reactor, which acts as a fermenter, are maintained for a considerable period of time to ensure that optimum treatment
of soil and water can occur. Anaerobic microbes thus grow and degrade the waste.
Diatomaceous earth and granulated charcoal are mixed with the slurry to increase
microbial growth. As soon as degradation is complete, the slurry is transferred to another
large concrete tank and treated with fresh microbial inocula. Now, aerobic conditions
are well maintained so soil wastes can be mineralized completely by the activity of these
aerobic microbes. The decontaminated or treated soil is then returned to the original
field from which it was excavated. Maintenance is much easier in this type of soil treatment of soil, but its requirements for larger space and longer time for decontamination
are disadvantages when compared to the slurry- phase bioremediation method.
6 Interventions to Ameliorate Heavy Metal Contaminated Soils Employing Fungal…
remediation is aerobic and is most effective in cleaning larger areas. Microbes
acts as catalysts and minimize toxicity to humans by reducing the levels of toxic
contaminants in the soil.
6.1.2 Remediation Ex Situ
The soil excavated or pumped from the site is treated to remove contaminants by ex
situ bioremediation. Because this technique removes the soil before treatment,
faster decontamination of soils and the ability to treat a wide range of toxins in soils
with easier manageability are its main advantages.
6.1.3 Slurry-Phase Technique
As the name implies, a slurry is prepared by using a bioreactor to mix the contaminated soil with water and various reagents. Harmful substances present in the soil
will contact the microorganisms by homogenization. Thereafter, oxygen and supplements are introduced to the slurry, blended to create an ideal environment for the
microorganisms to break down the contaminants. The soil is tested when separation
of water is complete, and thereafter supplanted in that location with naturally existing microflora. A faster rate of bioremediation is its advantage.
6.1.4 Solid-Phase Technique
Bioremediation by the solid-phase process treats a contaminated soil by digestion in
aboveground reactors. Anaerobic conditions inside the reactor, which acts as a fermenter, are maintained for a considerable period of time to ensure that optimum treatment
of soil and water can occur. Anaerobic microbes thus grow and degrade the waste.
Diatomaceous earth and granulated charcoal are mixed with the slurry to increase
microbial growth. As soon as degradation is complete, the slurry is transferred to another
large concrete tank and treated with fresh microbial inocula. Now, aerobic conditions
are well maintained so soil wastes can be mineralized completely by the activity of these
aerobic microbes. The decontaminated or treated soil is then returned to the original
field from which it was excavated. Maintenance is much easier in this type of soil treatment of soil, but its requirements for larger space and longer time for decontamination
are disadvantages when compared to the slurry- phase bioremediation method.
6 Interventions to Ameliorate Heavy Metal Contaminated Soils Employing Fungal…