1. Carbon Sequestration to Mitigate Climate Change
Dr. M.B. DODDAMANI
Associate Professor
Dept of Environmental Sciences
College of Agriculture
UAS, Dharwad-580 005
2. Global Concern is in the Air
From
Intergovernmental
Panel on
Climate Change
6. Result of Greenhouse Effect
Av Global Temp
No greenhouse gases -18C (0F)
With Greenhouse gases +14C (59F)
7. Global mean temperatures are rising faster with time
100 0.0740.018
50 0.1280.026
Warmest 12 years:
1998,2005,2003,2002,2004,2006,
2001,1997,1995,1999,1990,2000
Period Rate
Years /decade
8. Global warming unstoppable
Britain made uninhabitable by sever flooding
Mediterranean region abandoned
1 to 2oC INCREASE
European dying of heat stroke
Forests ravaged by fire
Stressed plants beginning to emit carbon rather than absorbing it
A third of all species face extinction
2 to 3oC INCREASE:
Carbon release from plants speeds global warming
Death of Amazon rainforest
Super hurricanes hit coastal cities
Starvation in Africa
3 to 4oC INCREASE:
9. End of life on earth with apocalyptic storms
Flash floods
Hydrogen sulphide gas and methane fireballs racing across the
globe with power of atomic bombs
Only fungi survive
4 - 5 0C INCREASE:
Methane from ocean floor accelerates global warming
Complete melting of ice from poles
Search for food may shift rapid polarization of human habitat
5 - 6oC INCREASE:
12. Why are Greenhouse Gases Important?
1. Global ecological concern for the anthropogenic
source of increasing concentration in the
atmosphere since 1750 (Intergovernmental Panel
on Climate Change, 2001):
CO2 – 31% increase
CH4 – 151% increase
N2O – 17% increase
2. Cause radioactive forcing of the atmosphere,
which could alter global temperature and
ecosystem functioning
3. Can be manipulated by human activities
13. Signs of Global Warming
• Sea level is rising
• Earth’s ice cover is shrinking
• Winter is becoming shorter by 11 day
(spring is 6 days earlier and fall is 5 days later)
• Coral is dying
• Mosquito-born diseases have reached
higher altitudes
• Extreme weather more common
14. What is CO2?
• Odorless, tasteless gas
• Absorbs IR Radiation
• Produced from the combustion of any
hydrocarbon (contains C and H) or
carbohydrate (contains C, H, and O)
15. Production of CO2
Coal: C + O2 CO2
Nat Gas: CH4 + 2O2 CO2 + 2H2O
Gasoline: C8H18 + 12.5O2 8CO2 + 9H2O
Sugar: C6H12O6 + 6O2 6CO2 + 6H2O
18. CO2 Reduction Options?
Main options:
Increasing energy efficiency of fossil fuel burning
technologies
Removing CO2 from exhaust gas streams
“Sequestration” of atmospheric CO2 into the land
and ocean
Turning to non-fossil fuel sources of energy
19. What is CO2 storage ?
CO2 storage/Carbon Sequestration is the
placement of CO2 into a depository in such a
way that it remains safely stored and not
released to the atmosphere. The viable
options are storage of CO2 into underground
geological formations, oceans, terrestrial
ecosystems and bio - sequestration.
20.
21.
22. Why is Carbon Sequestration Important?
Carbon sequestration (CS), representing one of three key approaches
to carbon management, which has received much less attention to date
Several reasons:
• CS could be a major tool for reducing carbon emissions from
fossil fuels.
• CS is compatible with the continued large-scale use of fossil fuels,
as well as greatly reduced emissions of CO2 to the atmosphere
• CS could offer other benefits such as:
-improve agricultural practices that could reduce soil erosion
-increase the sustainability of food production, conserve water, and biodiversity
-the development of exportable technologies to help the economy
23. Quantifying the Potential Carbon Sequestration
Assuming that CS systems has three objectives:
-increase the carbon in above-ground biomass
-increase the amount of carbon in below-ground systems (soil and sediment)
-manage land area with an emphasis toward carbon sequestration
The potential carbon sequestration (PCS) is estimated as:
PCS = [(ai AGCi + bi BGCi) ci LAi]
Where
ai = potential increase in above-ground carbon in the ith ecosystem
bi = potential increase in below-ground carbon in the ith ecosystem
ci = potential change in land area due to management for carbon
sequestration in the ith ecosystem
AGCi and BGCi are above-ground carbon and below-ground carbon
(root biomass + soil carbon) in the ith ecosystem
LA = land area of each ecosystem in the index year
24. Potential Carbon Sequestration Analysis
Four ways to increase above-ground carbon sequestration system:
• Increase the rate of accumulation of above-ground biomass (Pg C /yr)
• Increase the density of total biomass per area and or /density of carbon
in the above-ground biomass (Pg C /area)
• Increase beneficial use of biomass carbon in long-lived products
Four ways to increase below-ground carbon sequestration system:
• Increase the depth of soil carbon
• Increase the density of carbon (organic and inorganic) in the soil
• Increase the mass and /or depth of roots
• Decrease the decomposition rate of soil carbon
PCS depends on ecosystem and management!
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30. There are two ways to capture the CO2.
Post combustion capture
The first method is to capture CO2 after the combustion or post
combustion capture by
1. absorption by using liquid or solid chemicals.
2. adsorption by physical or chemical methods.
3. filtering using membrane filters.
31. Capturing CO2 by Chemical Absorption
The flue gas from a coal fired power plant contains about 12% CO2 with the rest being
N2 and Oxygen.
A 1000 MW Coal fired unit produces around 2500 tons of gas per hour, which requires
the separation of almost 300 tons per hour of CO2. The task is enormous.
How to cost effectively separate the CO2?
The simple method is to pass the gas through a chemical solvent that selectively
absorbs only the CO2 and keeps it in a weak chemical bond.
The O2 and N2 then release to the atmosphere.
The CO2 releases from the chemical solvent during regeneration by heat addition that
breaks the bond of the CO2. The almost pure CO2 is collected, compressed and sent to
storage. The retrieved solvent goes for re-use.
The most common chemical solvents used are amines. Amine capture is a proven
system in the natural gas cleaning process.
The scale of operations is much larger for the removal of CO2 from power plants. Even
though many pilot plants are in service, a commercially viable operation on a large scale
is yet to take place.
32. Separation with sorbents/solvents
Solvents
Amine scrubbing technology was established over 60 years ago in
the oil and chemical industries, for removal of hydrogen sulphide
and CO2 from gas streams Commercially, it is the most well
established of the techniques available for CO2 capture although
practical experience is mainly in gas streams which are chemically
reducing, the opposite of the oxidising environment of a flue gas
stream.
There are several facilities in which amines are used to capture
CO2 from flue gas streams today, one example being the Warrior
Run coal fired power station in the USA where 150 t/d of CO2 is
captured.
33. CO2 SEQUESTARTION; OTHER PROBABILITIES:
1. Agriculture
2. Enhanced Coalbed Methane Recovery (ECBM)
3. CO2Sequestration in Methane Hydrates
4. Ocean Sequestration
5. Terrestrial Sequestration
6. Bio-sequestration
7. Geological sequestration
34. Agriculture
• A large proportion of the mitigation potential of agriculture
(excluding bioenergy) arises from soil C sequestration,
which has strong synergies with sustainable agriculture and
generally reduces vulnerability to climate change.
• Agricultural practices collectively can make a significant
contribution at low cost
– By increasing soil carbon sinks,
– By reducing GHG emissions,
– By contributing biomass feedstocks for energy use
IPCC Fourth Assessment Report, Working Group III, 2007
35. No-Tillage Cropping Systems
Conservation Agriculture
•Restores soil carbon
•Conserves moisture
•Saves fuel
•Saves labor
•Lowers machinery costs
•Reduces erosion
•Improved soil fertility
•Controls weed
•Planting on the best date
•Improves wildlife habitat
36. Enhanced Coalbed Methane Recovery (ECBM)
Coal beds typically contain large amounts of methane rich gas that is
adsorbed onto the surface of the coal. The injected CO2 efficiently
displaces methane as it has greater affinity to the coal than methane.
CO2 enhanced
coal bed
methane
production
37. Ocean Sequestration
CO2 is soluble in ocean water, and oceans absorb and
emit huge amounts of CO2 into the atmosphere through
natural processes. Ocean Sequestration has huge potential
as a carbon storage sink.
Storage of CO2 in deep oceans has
been suggested as a means of
reducing inputs of greenhouse
gases to the atmosphere.
38. Terrestrial Sequestration
Terrestrial carbon sequestration is defined as either the net removal
of CO2 from the atmosphere or the prevention of CO2 net emissions from
the terrestrial ecosystems into the atmosphere. The following ecosystems
offer significant opportunity for carbon sequestration:
• Forest lands
• Agricultural lands
• Biomass croplands
• Deserts and degraded lands
• Wetlands and peat lands
39. Terrestrial Carbon Sequestration
1. Increasing the net fixation of atmospheric CO2 by
terrestrial vegetation with emphasis on enhancing
physiology and rate of photosynthesis of vascular
plants
2. Retaining carbon in plant materials and
enhancing the transformation of carbon to soil
organic matter
3. Reducing the emission of CO2 from soils caused
by heterotrophic oxidation of soil organic carbon
4. Increasing the capacity of deserts and degraded
lands to sequester carbon
40. Terrestrial Carbon Sequestration
Atmospheric
CO2
Plant
respiration
Animal
respiration
Soil respiration
Photosynthesis
Soil
organisms
Soil
organic
matter
Dissolved
CO
in water
2
Leachate
Atmospheric
N2
Mineralization
Denitrification
Biological
N fixation
Carbonate
minerals
Fossil fuels
CO2
N
N O
N
2
2
O
NH
volatilization
3
NH
fixation
4
Plant
uptake
Fertilizer
Carbon
Input
Carbon
Output
Soil
Carbon
Sequestration
42. • In India, the Oil &
Natural Gas Corp.
(ONGC) has proposed
CO2-EOR for
Ankleshwar Oil Field in
Western India.
•The CO2 is planned to
be injected @
600,000m3/d and is
sourced from ONGC gas
processing complex at
Hazira.
•The experimental and
modeling studies have
indicated an incremental
oil recovery of ~ 4 %
over the project life of 35
years besides the
potential to sequester 5
to 10 million tons of CO2
CO2 Injector
CO2 Pipeline from
Hazira Plant
First row of oil Producer.
To be closed after reaching
GOR of 500 v/v
Second row of oil Producer. To
be continued on production till
GOR reaches 500 v/v
CO2 moves through
formation mobilizing
residual oil by
swelling, vaporization
and reduction in
residual oil saturation
Ankleshwar Sands S3+4 : 69.33 MMt
Waterflood Recovery : 54%
Envisaged Tertiary Recovery : 5-7%
After, Suresh Kumar, Abstract, IWCCS-07
43. Conclusions
- CO2 storage R&D is still in early stage in India and developing cost
effective technologies for CCS are the major challenges to the
scientist and researchers.
-The environmental risks involved in the storage of CO2 particularly
in geological formations and oceans have to be evaluated in detail
by monitoring and modeling in terms of long term stability.
- Funding mechanisms to support R&D projects for CCS have to be
evaluated. 0.5% cess on power generation in the line of oil cess
may be good enough to sustain the same. The cess can be
operated by Energy Security Development Board, under the aegis
of Ministry of Power.
‘If every country was to spend just 2-3% of their GDP,
the impact of possible global climate change could be
mitigated’
- R.K.Pachauri, Economic Times Corp. Excellence Award
for 2006-07, New Delhi (29th Oct., 2007)
44. • It is one amongst the largest
ongoing projects for CCS in the
world.
• The Encana Cooperation has been
injecting 5,000 tonnes of CO2 per
day into in the Weyburn oil field for
the dual purpose of enhancing oil
recovery and the CO2 storage while
increasing the field’s production by
an additional 10,000 barrels per day.
• About 30 million tones of CO2 will
be injected and permanently stored
over the life of project producing
at least 130 million barrels of
incremental recovered oil.
Weyburn–Midale CO2 Monitoring and Storage Project, Canada
Injection of CO2 in the Oil Producing
Formations of the Weyburn Field
After, EERC, North Dakota.
45. Summary and Conclusions
Greenhouse gas concentrations in the atmosphere
are increasing and the threat of global change
requires our attention
A diversity of agricultural management practices
can be employed to sequester more carbon in
plants and soil
Syntheses of available data are needed
Gaps in our knowledge need to be researched
Strategies to sequester soil carbon will also likely
restore degraded land and avoid further
degradation
