2. BIOREMEDIATION
Bioremediation is
“the use of microorganisms to destroy or immobilize waste
materials”
OR
“the use of microorganisms metabolism to remove pollutants
from environment”
3. BIOREMEDIATION MECHANISM
Microorganisms destroy organic contaminants using the chemicals for their own growth
and reproduction
Organic chemicals provide:
Carbon-source of cell building material
Electrons-source of energy
Microorganisms include:
Bacteria (aerobic and anaerobic)
Fungi
Actinomycetes (filamentous bacteria))
8. Treatment process done in upper soil layer or bio treatment cells
The simplest of on site treatment
Nutrients are added to increase biodegradation by mixing soil by ploughing
Contaminants are removed in 4-6 months
Ex situ process conducted in bioreactors where contaminated soil or sluge is slurried
with water in mixing tanks
Sometimes contaminated soil are spread over a large area for treatment
This technique is used to treat
Oily sludge area
Petroleum refinery waste-includes pseudomonas ,various corynebacteria, mycobacteria, and
some yeasts
Pesticide contaminated soil
1. LAND FARMING
10. A process for treating contaminated soil using microbes in heat
generating process to degrade contaminants at accelerated rate
Composting material such as straw, bark and wood chips is mixed with
the contaminated soil and piled into heaps
Process work in the same way as normal system which rise the
temperature to 60 ◦C and above to cause microbial activity
Higher temperature encourage the growth of thermophilic bacteria
Increased costs of this type of system restrict it to highly contaminated
materials
2. COMPOSTING
12. Effective, low cost and environmental friendly technique
Soil clean up of heavy metals and organic compounds
Pollutants are absorbed in roots, thus plants removed could be
disposed or burned
Transgenic plants with exogenous metallothionein ( a metal
binding protein) used to remove metals
Sunflower plants were used to remove cesium and satrontium
from ponds of nuclear power plant
3. PHYTOREMEDIATION
14. The process by which metals are dissolved from ore bearing rocks using
microorganisms
Good method to extract metal from ore by means of microbes
Different metals are extracted such as
Gold
Silver
Copper
Zinc
Cobalt
Arsenic
Nickle
Antimony
Uranium
4. BIOLEACHING
17. The addition of archaea or bacterial cultures required to speed up the rate of
degradation of a contaminant
The introduction of more naturally occurring or GEMs (genetically engineered
microbes) cultures to enhance the contaminant degradation
If the indigenous variety do not have the metabolic capability to perform the
remediation process then exogenous varieties are introduced
Bacteria, fungi, protozoans, rotifers and nematodes are used
Technique used for
Municipal waste water treatment,
Activated sludge bioreactor
5. BIOAUGMENTATION
19. The method in which bacteria are motivated to start the process of bioremediation
The experts release nutrients and other important substances in the soil where there
is need or removing the contaminants
The nutrients may be phosphorus, nitrogen, oxygen, or carbon (e.g. in the form of
molasses)
These substances are gas or liquid in form to enhance the growth of microbes in that
area
As a result, microbes remove the contaminants quickly and efficiently
Biostimulation is usually associated with remediation of hydrocarbon or high
production volume chemical spills
6. BIOSTIMULATION