Fossil Power Plant
http://www.eoearth.org/article/Fossil_fuel_power_plant
Fossil fuel power plant[pic]
KohlekraftwerkScholven, a fossil fuel power plant in Germany.
(By Sebastian Schlüter - Basan1980, via Wikimedia Commons)
[pic]
A coal-fired power plant. Photo: DOE
A fossil fuel power plant is a system of devices for the conversion of fossil fuel energy to mechanical work or electric energy. The main systems are the steam cycle and the gas turbine cycle. The steam cycle relies on the Rankine cycle in which high pressure and high temperature steam raised in a boiler is expanded through a steam turbine that drives an electric generator. The steam gives up its heat of condensation in a condenser to a heat sink such as water from a river or a lake, and the condensate can then be pumped back into the boiler to repeat the cycle. The heat taken up by the cooling water in the condenser is dissipated mostly through cooling towers into the atmosphere.
The gas turbine cycle relies on the Brayton cycle in which air compressed to high pressure, and heated to high temperature by the combustion of natural gas or light fuel oil, is the working fluid that expands in the turbine to provide the torque for driving both a compressor and the electric generator. The gas turbine demands clean fuels such as natural gas or light fuel oil. Combustion is the prevailing fuel utilization technology in both the above cycles. Coal is the preferred fuel for the steam cycle because of its low cost and broad and secure availability worldwide.
Combustion-generated pollutants, such as oxides of nitrogen (NO,x), of sulfur (SOx), and particulates, if uncontrolled and emitted into the atmosphere represent environmental and health hazards, such as acid rain. Environmental regulations supported by intensive research and developments have reduced pollutant emissions significantly. Improvements in efficiency and emissions come by increasing steam pressure and temperature in the steam cycle, and by increased
Fossil fuel power plant[pic]
KohlekraftwerkScholven, a fossil fuel power plant in Germany.
(By Sebastian Schlüter - Basan1980, via Wikimedia Commons)
[pic]
A coal-fired power plant. Photo: DOE
A fossil fuel power plant is a system of devices for the conversion of fossil fuel energy to mechanical work or electric energy. The main systems are the steam cycle and the gas turbine cycle. The steam cycle relies on the Rankine cycle in which high pressure and high temperature steam raised in a boiler is expanded through a steam turbine that drives an electric generator. The steam gives up its heat of condensation in a condenser to a heat sink such as water from a river or a lake, and the condensate can then be pumped back into the boiler to repeat the cycle. The heat taken up by the cooling water in the condenser is dissipated mostly through cooling towers into the atmosphere.
The gas turbine cycle relies on the Brayton cycle in which air compressed to high pressure, and heated to high temperature by the combustion of natural gas or light fuel oil, is the working fluid that expands in the turbine to provide the torque for driving both a compressor and the electric generator. The gas turbine demands clean fuels such as natural gas or light fuel oil. Combustion is the prevailing fuel utilization technology in both the above cycles. Coal is the preferred fuel for the steam cycle because of its low cost and broad and secure availability worldwide.
Combustion-generated pollutants, such as oxides of nitrogen (NO,x), of sulfur (SOx), and particulates, if uncontrolled and emitted into the atmosphere represent environmental and health hazards, such as acid rain. Environmental regulations supported by intensive research and developments have reduced pollutant emissions significantly. Improvements in efficiency and emissions come by increasing steam pressure and temperature in the steam cycle, and by increased