Bioremediation uses microorganisms to break down hazardous substances into less toxic forms. There are two main techniques: in-situ treats contaminated soil and groundwater in place without excavation, while ex-situ excavates soil prior to treatment using methods like biopiles, bioreactors, land farming, and windrows that optimize conditions for microorganisms. The document discusses various enhanced bioremediation methods for both in-situ and ex-situ treatment.

1. Techniques for Bioremediation
DEPARTMENT OF BIOINFORMATICS AND
BIOTECHNOLOGY
GC UNIVERSITY FAISALABAD
HASNAT KHAN 16618

2. Bioremediation
Bioremediation is a treatment process that uses naturally occurring microorganisms (yeast, fungi,
or bacteria) to break down, or degrade, hazardous substances into less toxic or nontoxic
substances.
How does it work?
Bioremediation technologies assist microorganisms' growth and increase microbial populations
by creating optimum environmental conditions for them to detoxify the maximum amount of
contaminants. The specific bioremediation technology used is determined by several factors, for
instance, the type of microorganisms present, the site conditions, and the quantity and toxicity of
contaminant chemicals.

3. Bioremediation Techniques
In-situ
Soil and associated
ground water is
treated in place
without excavation
Ex-situ
Excavate prior to
treatment

4. In-situ Ex-situ
oOnly Ex-situ
process allow an
efficient
optimization of
incubation
parameters
(biostimulation)
Natural
Attenuation
Enhanced Biopile Windrow Bioreactor
Bioslurping
Bioventing
Biosparging Phytorediation
Land
Farming

5. In-situ
In situ remediation is
performed directly on the site
without excavating soil
contaminants or disturbance to
the soil structure.

6. Natural
Attenuation
Natural attenuation refers to
processes that naturally
transform contaminants to less
harmful forms or immobilize
contaminants so that they are
less of a threat to the
environment.
1. Volatilization
2. Incorporation as biomass
3. Degradation
4. Stabilization

7. Enhanced
Biosparging
Biosparging involve the injection of air under pressure
below the water table to increase groundwater oxygen
concentrations and enhance the rate of biological
degradation of contaminants by naturally occurring
bacteria.

8. Enhanced
Bioventing
Bioventing is a process of stimulating the natural in situ biodegradation of contaminants in soil
by providing air or oxygen to existing soil microorganisms.

9. Enhanced
Bioslurping
Bioslurping is the adaptation and application of
vacuum-enhanced dewatering technologies to
remediate hydrocarbon-contaminated
sites. Bioslurping utilizes elements of both,
bioventing and free product recovery, to address
two separate contaminant media.

10. Enhanced
Phytoremediation
Phytoremediation is a bioremediation process
that uses various types of plants to remove,
transfer, stabilize, and/or destroy contaminants in
the soil and groundwater.
Types of Phytoremediation
1. Rhizosphere biodegradation
2. Phyto-stabilization
3. Phyto-accumulation
4. Phyto-degradation

11. Ex-situ
Ex-situ bioremediation is a
biological process in which
excavated soil is placed in a
lined above-ground treatment
area and aerated following
processing to enhance the
degradation of organic
contaminants by the indigenous
microbial population.

12. Ex-situ
Land Farming
Land farming is a bioremediation treatment
process that is performed in the upper soil zone
or in biotreatment cells. Contaminated soils,
sediments, or sludges are incorporated into the
soil surface and periodically turned over or tilled
to aerate the mixture.
1. HDPE liner
2. Sump pump to collect leachate
3. Layer of pea gravel
4. Layer of polluted soil to be treated
5. Chopped alfalfa hay to retain moisture
6. Wheels on sprinkler piping system
7. Piping frame, aluminium or PVC pipes with frequent holes, sufficient to allow water, nutrients
and bacteria to treat the land farm plot
8. Flexible leachate collection hose.
9. Bypass valve that allows leachate to be circulated directly to water distribution tank, when
bioreactor is full or completing a bacterial growth cycle
10. Recirculation hose
11. Alken-Murray Bio activator 2000, bioreactor unit
12. Fresh water supply hoses
13. Pumps for fresh water
14. Treated water hose
15. Water distribution tank
16. Pump for distribution tank

13. Ex-situ
Biopile
Bio piling is a full-scale
technology in which excavated
soils are piled and typically
constructed in a treatment area that
consists of a leachate collection
and aeration system. It is
commonly applied to reduce
concentrations of petroleum
components in soils through
utilising the process of
biodegradation.

14. Ex-situ
Bioreactor
The term "bioreactor" in the context of soil and
water bioremediation refers to any vessel or
container where biological degradation of
contaminants is isolated and controlled.

15. Ex-situ
Windrow
One of ex situ bioremediation techniques,
windrows rely on periodic turning of piled
polluted soil to enhance bioremediation by
increasing degradation activities of
indigenous and/or transient hydrocarbon
clastic bacteria present in polluted soil.
Windrow treatment when compared to
biopile treatment, showed higher rate of
hydrocarbon removal; however, the higher
efficiency of the windrow towards
hydrocarbon removal was as a result of the
soil type, which was reported to be more
friable.