Abstract:
The
paper presents how to generate power from coal. In this paper we will discuss
about coal, composition of coal, types or ranks of coal, coal to power
generation technique, pollutants from coal fired power plant, emission control
of coal fired power plant, advantages and disadvantages of coal fired power plant.
Coal:
Coal is a flammable black hard rock used as a solid fossil
fuel. It is mainly made up of 65-95% carbon and also contains hydrogen,
sulphur, oxygen and nitrogen. It is a sedimentary rock formed from peat, by the
pressure of rocks laid down later on top.
Composition of Coal:
The composition of
coal has been given below-
Figure: Composition of Coal
Types or Ranks of Coal:
The ranks of coal (from most to
least carbon content) are mainly as follows: anthracite, bituminous coal,
subbituminous coal, and lignite. The coal with the highest carbon content is
the best and cleanest type of coal to use.
Figure: Types or Ranks of Coal
Coal to Power Generation
Technique:
Power is generated from coal by the following steps-
Figure: Coal to Power Generation Technique
1. Heat is
created:
Before
the coal is burned, it is pulverized to the fineness of talcum powder. It is
then mixed with hot air and blown into the firebox of the boiler. Burning in
suspension, the coal/air mixture provides the most complete combustion and
maximum possible heat.
2. Water turns to steam:
Highly
purified water, pumped through pipes inside the boiler, is turned into steam by
the heat. The steam reaches temperatures of up to 1,000 oF and
pressures up to 3,500 psi, and is piped to the turbine.
3. Steam turns the turbine:
The
enormous pressure of the steam pushing against a series of giant blades turns
the turbine shaft. The turbine shaft is connected to the shaft of the
generator, where magnets spin within wire coils to produce electricity.
4. Steam turns back into water:
After
doing its work in the turbine, the steam is drawn into a large chamber in the basement
of the power plant. In this important step, millions of gallons of cool water
from a nearby source (such as a river or lake) are pumped through a network of
tubes running through the condenser. The cool water in the tubes converts the
steam back into water that can be used over and over again in the plant. The cooling water is returned to its source without
any contamination, and the steam water is returned to the boiler to repeat the
cycle.
Pollutants from Coal Fired Power
Plant:
Pollutants found from coal combustion and their effects have been tabulated below-
Pollutants found from coal combustion and their effects have been tabulated below-
Pollutants
|
Effects
|
Carbon
Dioxide
|
Greenhouse
Gas
|
Carbon
Monoxide
|
Toxic
|
Sulphur
Oxides
|
Acid
Rain
|
Nitrogen
Oxides
|
Ozone
Depletion & Smog
|
Hydrocarbons
|
Toxic
& Greenhouse Gas
|
Smoke
|
Visible
Pollution
|
Emission Control of Coal Fired
Power Plant:
The
following technologies can be used for the emission control of coal fired power
plant-
1. Pre-Combustion
CO2 Capture
2. During
Combustion CO2 Capture or Oxy-Fuel-Combustion Technology
3. Post-Combustion
CO2 Capture
4. Absorption
Technology
5. Membrane
Technology
6. PSA
(Pressure Swing Adsorption) Technology
7. Mineral
Carbonation Technology
Advantages of Coal Fired Power
Plant:
1. Reliability
2. Affordability
3. Abundance of coal
4. Known technologies
5. Safety
Disadvantages of Coal Fired Power
Plant:
1. Greenhouse gas emissions
2. Mining destruction
3. Generation of millions of tons of waste
4. Emission of harmful substances
5. Non renewable energy
Conclusion:
Coal to power generation technique was discussed in this article. This
article will help us to generate more power from coal by controlling the
emission of coal fired power plant.
References:
