Coal Mines

1
Coal Mines The Effects They Produce

• Tyler Morin Holly Schwichtenburg

2
What is Coal Anyways?

• A combustible and sedimentary organic rock
• Main components are carbon, hydrogen oxygen
  also contain varying amounts of sulfur and
  nitrogen
• Formed from vegetation that has been consolidated
  between layers of rock and has been subjected to
  changes in pressure and heat over time
• Higher carbon content means higher amount of
  energy

3
Iron Pyrite (FeS2)

• A common material in coal mines
• Mine tailings a source of metal and nonmetal
  contamination in coal
• From mine tailings
• contributes iron and sulfur to water pollution
• contributes production of sulfur oxides in flue
  gases when coal is burned which leads to acid
  rain

4
Water Pollution

• Contributes to water production when sulfide is
  oxidized to sulfate and the Fe(II) is oxidized to
  Fe(III)
• 4FeS2 15O2 6H2O? 4Fe(OH)2 HSO4-
• The result is a dilute solution of sulfuric acid
  containing Fe(II), Fe(III), and other heavy metal
  ions

5
Effects of Water Pollution

• In areas with old mines such acidic solutions are
  common in streams and rivers
• pH values as low as 2-3.5 have been measured
• This effectively kills most plant and animal life
  in the water

6
Effects of Burning Coal

• When coal containing sulfur compounds are burned
  it results in sulfur dioxide and sulfur trioxide
  which contaminate the atmosphere
• Sulfur oxides are readily dissolved in water
  droplets in the atmosphere and return to the
  earth as acid rain
• Acid rain has damaged forests, lakes, building
  materials, and artistic works globally

7
Smelting

• Process of purifying metals by roasting the ore
  in air to convert it into the oxide
• MS 3/2 O2 ? MO SO2 (M Cu, Ni)
• Smelting is not a major source of sulfur oxides
  but it does show the dramatic effects of
  pollution
• For example sites studied in Canada show
  vegetation damage and evidence of acidified lakes
  up to 40 miles away from the plant

8
Control of SO2 Emissions

• EPA is controlling agency
• Clean Air Act
• No more than 8.90 million tons of sulfur dioxides
  per year total
• Penalties vary by amount in excess
• Regulate by issuing permits to individual plants
  that state the total amount they are allowed to
  produce based on size of plant
• Continuous Emissions Monitoring System
• Scrubbers on Smokestacks

9
Ultimate Fate of Emissions

• Acid Rain is main effect of sulfur dioxides
• Ecosystems (i.e. aquatic life, soils and
  rainforests) will be ruined
• Buildings and other landmarks will become ruined

10
References

• Advanced Inorganic Text
• www.epa.gov