Clean Coal technology Renewable and nonrenewable energy

1. Clean Coal Technologies

2. Environmental Problems Due to
Coal Utilization
 Most of the coal found in the country is of poor
Most of the coal found in the country is of poor
quality, high sulphur, ash and moisture content,
quality, high sulphur, ash and moisture content,
which makes its use unsuitable for domestic,
which makes its use unsuitable for domestic,
power and most of the industrial applications.
power and most of the industrial applications.
 The conventional combustion of coal results in
The conventional combustion of coal results in
the byproducts of sulfur dioxide (SO
the byproducts of sulfur dioxide (SO2
2), nitrogen
), nitrogen
oxides (NOx), Carbon Dioxide (CO
oxides (NOx), Carbon Dioxide (CO2
2), particulates
), particulates
etc, which if not controlled contribute to the
etc, which if not controlled contribute to the
production of acid rain, greenhouse effect and
production of acid rain, greenhouse effect and
many other environmental problems.
many other environmental problems.

3. Coal Utilization with Clean
Coal Technologies
 CCTs are addressing these environmental problems so
CCTs are addressing these environmental problems so
that the world's enormous resources of coal can be
that the world's enormous resources of coal can be
utilized for future generations without contributing to
utilized for future generations without contributing to
acid rain, global warming and other environmental
acid rain, global warming and other environmental
problems.
problems.
 CCTs allow coal to be burned more efficiently, with
CCTs allow coal to be burned more efficiently, with
reduced emissions of sulfur and nitrogen oxides, while
reduced emissions of sulfur and nitrogen oxides, while
providing distinct advantages over conventional coal
providing distinct advantages over conventional coal
utilization systems.
utilization systems.
 CCTs can be grouped in four categories:
CCTs can be grouped in four categories:
(1)
(1) Precombustion
Precombustion (2)
(2) Advanced Combustion
Advanced Combustion
(3)
(3) Postcombustion
Postcombustion (4)
(4) Conversion Technologies
Conversion Technologies

4. Pre-Combustion
 Often referred to as coal cleaning or "washing",
Often referred to as coal cleaning or "washing",
these technologies (physical, chemical, and
these technologies (physical, chemical, and
biological cleaning) both improve the general
biological cleaning) both improve the general
coal quality and remove sulfur, ash and other
coal quality and remove sulfur, ash and other
contaminants from the feed coal.
contaminants from the feed coal.
 Precombustion technologies have a significant
Precombustion technologies have a significant
potential for lowering the costs of SO
potential for lowering the costs of SO2
2 emission
emission
reduction when used with other, lower cost
reduction when used with other, lower cost
advanced combustion or postcombustion
advanced combustion or postcombustion
technologies.
technologies.

5. Advanced Combustion
 These technologies can be used to upgrade existing
These technologies can be used to upgrade existing
power plants through retrofitting and repowering, or in
power plants through retrofitting and repowering, or in
greenfield applications for complete replacement.
greenfield applications for complete replacement.
 Advanced combustion processes are the most efficient
Advanced combustion processes are the most efficient
coal technologies available for new power plant
coal technologies available for new power plant
construction.
construction.
 Atmospheric and pressurized fluidized bed combustion
Atmospheric and pressurized fluidized bed combustion
(AFBC and PFBC) systems can reduce more than 95%
(AFBC and PFBC) systems can reduce more than 95%
of the SO
of the SO2
2 released during coal burning.
released during coal burning.
 NOx reductions are also achieved through combustion
NOx reductions are also achieved through combustion
temperatures lower than in conventional boilers.
temperatures lower than in conventional boilers.
 Their higher efficiencies reduce CO
Their higher efficiencies reduce CO2
2 emissions.
emissions.

6. Coal Washing
Grinding coal into pieces and passing it through
Grinding coal into pieces and passing it through
gravity filtration
gravity filtration
One technique: Putting coal into a barrel with a
One technique: Putting coal into a barrel with a
liquid with a specific density where the coal floats
liquid with a specific density where the coal floats
and the impurities sink
and the impurities sink

7. Post-Combustion
 Because today's "scrubbers" (flue gas desulphurization
Because today's "scrubbers" (flue gas desulphurization
systems) are incapable of removing NOx,
systems) are incapable of removing NOx,
postcombustion technologies are being developed for
postcombustion technologies are being developed for
retrofit applications.
retrofit applications.
 Designed to remove SO
Designed to remove SO2
2 and NOx after the coal has been
and NOx after the coal has been
burned, they are typically installed on the stacks of
burned, they are typically installed on the stacks of
power plants.
power plants.
 Unlike combustion technologies, postcombustion
Unlike combustion technologies, postcombustion
technologies target existing power plants exceeding
technologies target existing power plants exceeding
emissions restrictions.
emissions restrictions.
 In most cases, these retrofit systems offer short-term,
In most cases, these retrofit systems offer short-term,
cost effective, remedies for severe environmental
cost effective, remedies for severe environmental
problems.
problems.

8. Conversion Technologies
 These techniques convert coal into clean gas or
These techniques convert coal into clean gas or
liquid fuel prior to combustion in order to bypass
liquid fuel prior to combustion in order to bypass
or eliminate direct coal combustion altogether.
or eliminate direct coal combustion altogether.
 Integrated Gasification Combined Cycle (IGCC) is
Integrated Gasification Combined Cycle (IGCC) is
the best known of these systems. IGCC plant is a
the best known of these systems. IGCC plant is a
means of using coal and steam to produce hydrogen
means of using coal and steam to produce hydrogen
(H
(H2
2) and carbon monoxide (CO) which are then
) and carbon monoxide (CO) which are then
burned in a gas turbine with secondary steam
burned in a gas turbine with secondary steam
turbine (i.e. combined cycle) to produce electricity.
turbine (i.e. combined cycle) to produce electricity.
 If the gasifier is fed with oxygen rather than air, the
If the gasifier is fed with oxygen rather than air, the
flue gas contains highly-concentrated CO
flue gas contains highly-concentrated CO2
2 which
which
can readily be captured - at about half the cost of
can readily be captured - at about half the cost of
capture from conventional plants.
capture from conventional plants.

10. Gasification
Gasification is seen as part of zero-emission system
Gasification is seen as part of zero-emission system
Improved SO2 and NOx emissions (already low)
Improved SO2 and NOx emissions (already low)
Unproven on widespread scale
Unproven on widespread scale
Up to 45% efficient
Up to 45% efficient
Currently only demonstration units exist on a trial
Currently only demonstration units exist on a trial
basis
basis
Right now syngas being cleaned at low temperatures.
Right now syngas being cleaned at low temperatures.
In the future will be cleaned at higher temperatures,
In the future will be cleaned at higher temperatures,
increasing efficiency
increasing efficiency
Costly, but current coal power plants can be modified
Costly, but current coal power plants can be modified

13. Integrated Gasification Combined Cycle

14. Conversion Technologies
 Development of this oxygen-fed IGCC process will add a
Development of this oxygen-fed IGCC process will add a
shift reactor to oxidize the CO with water so that the gas
shift reactor to oxidize the CO with water so that the gas
stream is basically just H
stream is basically just H2
2 and CO
and CO2
2.
.
 These are separated before combustion and the H
These are separated before combustion and the H2
2 alone
alone
becomes the fuel for electricity generation (or other uses)
becomes the fuel for electricity generation (or other uses)
while the concentrated pressurized CO
while the concentrated pressurized CO2
2 is readily disposed
is readily disposed
of.
of.
 Sulfur is converted almost entirely to hydrogen sulfide
Sulfur is converted almost entirely to hydrogen sulfide
during gasification process, which is then recovered.
during gasification process, which is then recovered.
 Resulting generating efficiencies are increased by 40% to
Resulting generating efficiencies are increased by 40% to
45% and SO
45% and SO2
2 and NOx reductions are reduced by over
and NOx reductions are reduced by over
95%.
95%.

15. Conversion Technologies
 The CCT field is moving very rapidly in the direction of
coal gasification which offers one of the most versatile
and cleanest ways to convert the energy content of coal
into electricity, hydrogen, and other energy forms.
 Many experts predict that coal gasification will be at the
heart of the future generations of clean coal technology
plants for several decades into the future.
 Among various clean coal technologies, gasification also
appears to be a very attractive technology for utilization
of Pakistani coals.
 Indigenous coal could be developed and utilized with
CCTs for meeting the fast growing commercial energy
demand and increasing the economic independence in
the country.

16. Carbon Capture and Storage
(CCS)
Capturing CO2 and storing it underground
Capturing CO2 and storing it underground
(geosequestration)
(geosequestration)

17. There are many problems with CSS
There are many problems with CSS
CO2 is hard to capture
CO2 is hard to capture
Once captured it needs to liquified which takes
Once captured it needs to liquified which takes
20% of the energy yielded from the coal
20% of the energy yielded from the coal
Where the CO2 is stored needs to be monitored
Where the CO2 is stored needs to be monitored
There are only so many places that are good for
There are only so many places that are good for
mass storage
mass storage
Transportation could be costly
Transportation could be costly
Carbon Capture and Storage (CCS)

18. Indigenous Coal Utilization
Options
Indigenous coal can be utilized in power
Indigenous coal can be utilized in power
generation, processing industry (including
generation, processing industry (including
cement, sugar and fertilizers), domestic
cement, sugar and fertilizers), domestic
sector as smokeless briquettes, production
sector as smokeless briquettes, production
of town gas as an alternative to liquefied
of town gas as an alternative to liquefied
petroleum gas (LPG), gasifying the coal in-
petroleum gas (LPG), gasifying the coal in-
situ to supplement natural gas resources,
situ to supplement natural gas resources,
extracting and using coal bed methane and
extracting and using coal bed methane and
producing substitute natural gas on the
producing substitute natural gas on the
surface.
surface.

19. Benefits of Indigenous Coal Utilization
 Indigenous coal utilization would have multidimensional
Indigenous coal utilization would have multidimensional
effect on the economy interalia including the reduction
effect on the economy interalia including the reduction
in oil import bills, creation of employment opportunities
in oil import bills, creation of employment opportunities
and socio-economic uplift of the area, where these mines
and socio-economic uplift of the area, where these mines
are situated.
are situated.
 Further the development of coal resources for power
Further the development of coal resources for power
generation would have supplemental effect on Hydel
generation would have supplemental effect on Hydel
Power Generation, which has the seasonal variation in
Power Generation, which has the seasonal variation in
the available capacity.
the available capacity.
 The use of indigenous coal as an energy input in the
The use of indigenous coal as an energy input in the
industry will not only make our products price-
industry will not only make our products price-
competitive but also promises enormous savings to the
competitive but also promises enormous savings to the
industry as well as the national exchequer on account of
industry as well as the national exchequer on account of
abandoning import of furnace oil and coal.
abandoning import of furnace oil and coal.

20. Thank You
Thank You