power plants supply 50 percent of the nation’s electricity, but these plants
also produce air pollution. Coal plants emit approximately 87 percent of
nitrogen oxide (NOx) pollution, 94 percent of sulfur dioxide (SO2) and 98
percent of mercury pollution. Compared with others, coal plants are the largest
source of sulfur dioxide, mercury and air toxic emissions and second largest
source of nitrogen oxide pollution. These pollutants emitted from coal plants
are combined to form secondary pollutants such as ozone and particulate matter
that are dangerous to public health.
Sulfur Dioxide (SO2)
In United State, coal plants are the
largest source of SO2 pollution, which is dangerous to public health. It forms
small acidic particulates by combining with air that is dangerous to human
lungs and also absorbed by bloodstream. An uncontrolled coal plants emit 14,100
tons of SO2 per year and an controlled coal plants emits 3,300 tons of NOx per
Nitrogen Oxides (NOx)
pollution causes ozone, or smog, which causes eye, nose, throat and chronic
respiratory diseases. An uncontrolled coal plant emits 10,300 tons of NOx per
year while a controlled coal plant emits 3,300 tons of NOx per year.
Particulate matter (also referred as
soot or fly ash) causes eye, bronchitis, lungs, heart and chronic respiratory
diseases, premature death. An uncontrolled coal plant emits 500 tons of small
airborne particles each year. Baghouse (installed inside coal plant) can
capture 99 percent of the particulates. Coal plants are responsible for nearly
24,000 deaths each year.
In U.S. coal plants cause more than half
emission of mercury. It causes brain damage, heart problems, learning
disabilities and attention deficit disorders in childhood. An uncontrolled coal
plant emits approximately 170 pounds of mercury each year. Activated carbon
technology can minimize mercury emission up to 90 percent when combined with
baghouses, Just 1/70th of mercury deposited on 25-acre make the fish
unsafe to eat.
Coal contains low level of uranium,
thorium and other naturally occurring radioactive isotopes that leads to
radioactive contamination of environment. These can cause human diseases and
can effect to plants and crops. Emitted radiation by coal-derived fly ash
delivers 100 times more to the environment than normal productive nuclear
plant. The 1000-MWe coal-fired power plant emits nuclear radiation dose of 490
person-rem/year, compared to 136 person-rem/year for other nuclear power plant
including uranium mining, reactor operation and waste disposal.
River Water Pollution
Coal power plant produces ash containing
calcium oxide (CaO). CaO dissolves in water forming slaked lime Ca(OH)2 and
carried by acid rain to rivers. It removes temporary hardness of water but
increases sodium ions (by converting sodium bicarbonates into sodium
carbonates) that converts the fertile land into alkaline soil.
pollution (known as smog) is formed when NOx reacts with volatile organic
compounds (VOCs) in the presence of sunlight. In U.S. one third populations
living in unhealthful ozone levels areas. Smog can cause health problems like;
respiratory diseases, coughing, wheezing, chest pain and premature death.
Coal-fired power plants are significant
source of carbon dioxide emissions, producing approximately 40 percent of total
U.S. carbon dioxide pollution. Carbon dioxide has no direct effect on human
health but it can harm global warming that can cause different diseases in
human. World Health Organization estimates that approximately 150,000 deaths occurred
due to climate change.