Open Pit Mining
Kennecott Copper Mine in Bingham Canyon, Utah is the largest mine in the world. It is an Open Pit Mine which uses explosives and machines to create holes and extract ore.
Chain buckets and drag lines scrape underwater mineral deposits.
Area Strip Mining
Flat terrain mining where earth is removed in strips or layers to extract ore. Leaves spoil banks behind filled with overburden. This is common with coal.
Contour Strip Mining
Used for hilly, mountainous terrain, this type of mining cuts a series of terraces along the contours (areas of equal elevation) of the land. A wall of dirt is left in front of a highly erodible bank of soil and rock called a Highwall.
Mountain Top Removal
- Removes top of mountain to expose seams of coal underneath
- Common in West Virginia
- Causes considerable environmental damage
- In 2002, Gov't allowed debris from tops to be dumped into streams/valleys below
Nonrenewable energy sources
Nonrenewable sources of energy are solids, liquids, or gases that are extracted from the Earth and have high chemical potential energy that can be used to generate electricity or fuel transportation. All Fossil Fuels emit Greenhouse Gases, are limited in supply, and pollute air and water. The following charts show the amounts and types of energy consumed by the U.S.
The Dirtiest Fossil Fuel: COAL
The following are maps that show the U.S. Consumption of coal followed by maps of Particulate and Sulfur Dioxide emissions. The East Coast of the U.S. has the worst air pollution in North America.
Source: ore in the Earth’s crust-mostly carbon with trace sulfur and radioactive materials
Use: electricity and heat
Coal is burned to heat water and steam turns turbines which generate electricity or the heat is used directly as a cooking source.
Benefits: Coal is abundant and cheap to mine and process. It has a high heat content and an efficiency of around 30%
Drawbacks: Coal is dirty to burn with Sulfur Dioxide, Carbon Dioxide, Nitrogen Oxides, particulates, mercury, and radioactive isotopes emitted.
Technology to Clean Coal
Coal Washing: settle impurities before burning by rinsing with water
Wet Scrubbers: spray flue gas with limestone solution—forms gypsum (drywall) and is the best method for reducing Sulfur Dioxide emissions by turning it into Sulfuric Acid which can be stored.
Low Nox Burners: restricts oxygen so it can’t react with nitrogen
Electrostatic Precipitators: charge particulate matter with electric field and are the most efficient way to collect all but the fine and ultrafine particulates.
Petroleum/Oil: Liquid Gold
Source: Formed from decomposition of organic matter; located deep in crust-under lakes & oceans
Primary extraction is through drilling/pumping.
Use: Produces petrochemicals for organic chemicals, pesticides, plastics, synthetic fibers, paint, and gasoline.
Production: Crude oil is refined for use through boiling it in a distillation column.
Tar Sands in Alberta Canada
Tar Sand is a mixture of Bitumen, clay, sand, and water that can be refined to make a crude oil.
The extraction of Tar Sand requires the use of large quantities of water.
This oil has a low energy yield and a high cost and is carried to the U.S. through the Keystone Pipeline. The oil must be heated from 130 to 160 degrees F in order to be moved and the pipeline has the worst spill rate of oil on record.
Is a type of sedimentary rock that contains Kerogen, which can be turned into Bitumen when heated and refined in the petroleum generation process.
Oil shale is significantly more abundant than conventional oil, but it is very low grade oil and not worth the investment at this time.
Natural Gas: The Cleanest Dirty Fuel
Methane is the primary natural gas collected through the Hydraulic Fracturing (Fracking) process.
Risks associated with Fracking include:
Stress of surface water and ground water supplies from the withdrawal of large volumes of water,
Contamination of underground sources of drinking water and surface waters,
Adverse impacts from discharges into surface waters or from disposal into underground injection wells,
Air Pollution resulting from the release of volatile organic compounds, hazardous air pollutants, and greenhouse gases.
Benefits of Natural Gas:
High Energy Yield
Less Air Pollution
High Efficiency of around 30% (similar to coal)
The Shearon Harris Nuclear Power Plant in Holly Springs, NC is pictured here.
Nuclear Reactors in the U.S. use nuclear fission to create energy, which is the splitting of large atoms through the collision of neutrons. The fissionable fraction of the fuel in a nuclear reactor is Uranium 235.
Control rods are used to absorb these neutrons when power generation is not needed. The control rods are lifted in order to allow fission to occur. The heat generated creates steam which turns the turbine to create electricity. Water is the most common moderator used to contain the radiation from the reactions.
The only emission that results from nuclear generation is Water Vapor.
The primary drawback to nuclear power is the storage of the spent fuel rods when they are no longer in use.