Waste water treatment and Energy Generation using Bacteria

1. BIOTECHNOLOGY
FOR
WASTE MANAGEMENT
--- ARUNKUMAR S. YADAV

2. What is Biotechnology ?
‘Biotechnology is the application of science and technology to living organisms, as well as
parts, products and models thereof, to alter living or non-living materials for the production
of knowledge, goods and services.’
Biotechnology has various application fields ranging from waste treatment to medical
treatment of cancer. A cleaner environment, advanced methods of diagnosis and medical
treatment, better products and alternative energy resources can be considered among the
benefit of biotechnology.

3. Importance of Biotechnology in
Waste Management
Environmental pollution is today, one of the most important problems in all world
countries.Biotechnology offers many treatment methods to overcome this pollution problem.
Biotechnology finds application fields in the treatment of wastewaters by biological methods
and disposal of solid wastes by composting technique in waste management. Biological methods are
also applied to treatment of air emissions. The methods based on biotechnology in wastewater
treatment are activated sludge,trickling filters, oxidation ponds, biofilters and anaerobic treatment.
Furthermore, solid waste composting techniques, biotrickling filters and biosorption are the
examples of biotechnology applications in waste management.
In all these methods, it is essential to find suitable microorganisms that will degrade organic
substances and to complete the treatment process in favorable conditions.

4. Biotechnology for Waste Management
using Microbial Fuel Cell
We know how Biotechnology has various applications in
Waste Management and it is widely used everywhere in the world.
One such application of Biotechnology is in Microbial Fuel
Cell which not only helps in waste water management but also
produces energy simultaneously. The energy generated in form of
electricity can be utilised somewhere in operations of Effluent
treatment Plant .

5. What is Microbial Fuel Cell?
 A microbial fuel cell (MFC) is a bioreactor, that converts chemical energy in the chemical bonds
in organic compounds to electrical energy through catalytic reactions of microorganisms under
anaerobic conditions.
 First demonstration of current and voltage generation via microorganisms was shown by a
botany Prof. Michael Cresse Potter, in 1911.
 Dependency on energy derived from fossil fuels and environmental concerns led researches on
MFC accelerate for the last two decades.

6. Components of Microbial Fuel Cell
(two chamber MFC type)
•Anode chamber
•Cathode chamber
•Electrodes
1. For Anode Materials used are:
(carbon felt, graphite felt etc.)
2. For Cathode Materials used are:
( activated carbon , graphite etc.)
•Ion exchange membrane or
salt bridge

7.  Microbes oxidise organic matter in anode chamber due to
which electrons and protons are released.
 Electrons flow to the cathode through external circuit
producing electric current.
 Protons flow through the membrane to the cathode.
 O2 or any other electron acceptor reacts with electrons and
protons forming water.
 Anode chamber is in anaerobic condition while cathode
chamber is in aerobic condition with oxygen or an elecctron
acceptor.
Reactions:(for acetate as a substrate)
Anode: CH3 COO-- + 2H2O 2CO2 + 7H+ + 8e—
Cathode: O2 + 4e-- + 4H 2H2O
Overall Mechanism of Microbial Fuel Cell

8. My apparatus

9. Our Experimented Readings for Effluent water
from LUPIN LTD.
0
20
40
60
80
100
120
DAY 1 DAY 2 DAY 3 DAY 4 DAY 5
VOLTAGE GENERATION (mV)
mV

10. Operating Conditions for my setup
1. Room Temperature
2. Microbes already present in Effluent water
3. Carbon Electrodes
4. Salt Bridge with KCl electrolyte instead of Proton Exchange Membrane.
5. pH 6-8
6. Oxygen used as electron acceptor
7. Later used Curd in Anode compartment containing lactobacillus plantarum
bacteria.

11. Conclusion
Microbial fuel cell is a good step towards waste management and renewable source
of energy useful to meet some demands of energy in future. Though it has some
limitations it will be improved in forthcoming years and by use of MFC’s alongwith
other Renewable sources like Solar, Tidal, Hydro etc. we can make our energy
sources cleaner and greener and treat waste water at low cost.

12. THANK YOU