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ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES

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ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES The extraction, processing, and use of mineral resources has a large environmental impact. Figure 15-9 – PowerPoint PPT presentation

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Title: ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES


1
ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES
  • The extraction, processing, and use of mineral
    resources has a large environmental impact.

Figure 15-9
2

Natural Capital Degradation
Extracting, Processing, and Using Nonrenewable
Mineral and Energy Resources
Steps
Environmental effects
Mining
Disturbed land mining accidents health hazards,
mine waste dumping, oil spills and blowouts
noise ugliness heat
Exploration, extraction
Processing
Solid wastes radioactive material air, water,
and soil pollution noise safety and health
hazards ugliness heat
Transportation, purification, manufacturing
Use
Noise ugliness thermal water pollution
pollution of air, water, and soil solid and
radioactive wastes safety and health hazards
heat
Transportation or transmission to individual
user, eventual use, and discarding
Fig. 15-10, p. 344
3
Costs
Harvesting Nonrenewable Resources
  • Ownership costs equipment, labor, safety
    (insurance), environmental costs (reclamation,
    pollution control, air monitors, water treatment,
    etc.), taxes
  • External costs processing the resource,
    transporting the resource
  • Marginal costs research finding new sources
    of the resource and new ways to harvest it

4
Benefits
  • Direct money received for resources provides
    many jobs
  • Indirect land can be reclaimed (brought back to
    original condition) and sold for profit.

5
ENVIRONMENTAL EFFECTS OF USING MINERAL RESOURCES
  • Minerals are removed through a variety of methods
    that vary widely in their costs, safety factors,
    and levels of environmental harm.
  • A variety of methods are used based on mineral
    depth.
  • Surface mining shallow deposits are removed.
  • Subsurface mining deep deposits are removed.

6
Methods
  • Surface Mining
  • Description if resource is lt200 ft. from the
    surface, the topsoil is removed (and saved),
    explosives are used to break up the rocks and to
    remove the resource, reclamation follows
  • Benefits cheap, easy, efficient
  • Costs tears up the land (temporarily),
    byproducts produce an acid that can accumulate in
    rivers and lakes

7
Methods (Continued)
  • Underground Mining
  • Description digging a shaft down to the
    resource, using machinery (and people) to tear
    off and remove the resource
  • Benefits can get to resources far underground
  • Costs more expensive, more time-consuming, more
    dangerous

8
Methods (Continued)
  • Reclamation
  • Description returning the rock layer
    (overburden) and the topsoil to a surface mine,
    fertilizing and planting it
  • Benefits restores land to good condition
  • Costs expensive, time-consuming

9
Specific Resources Their Uses
Specific Nonrenewable Resources
  • Coal formed from ancient peat bogs (swamps)
    that were under pressure as they were covered.
  • Used for electricity, heat, steel, exports, and
    industry, may contribute to the Greenhouse
    Effect
  • Four types of coal exist lignite (soft, used
    for electricity), bituminous and subbituminous
    (harder, also used for electricity) and
    anthracite (hardest, used for heating)
  • 50 of all the coal is in the United States, the
    former Soviet Union and China

10
Open-pit Mining
  • Machines dig holes and remove ores, sand, gravel,
    and stone.
  • Toxic groundwater can accumulate at the bottom.

Figure 15-11
11
Area Strip Mining
  • Earth movers strips away overburden, and giant
    shovels removes mineral deposit.
  • Often leaves highly erodible hills of rubble
    called spoil banks.

Figure 15-12
12
Contour Strip Mining
  • Used on hilly or mountainous terrain.
  • Unless the land is restored, a wall of dirt is
    left in front of a highly erodible bank called a
    highwall.

Figure 15-13
13
Mountaintop Removal
  • Machinery removes the tops of mountains to expose
    coal.
  • The resulting waste rock and dirt are dumped into
    the streams and valleys below.

Figure 15-14
14
(No Transcript)
15

Solutions
Sustainable Use of Nonrenewable Minerals
Do not waste mineral resources.
Recycle and reuse 6080 of mineral resources.
Include the harmful environmental costs of
mining and processing minerals in the prices of
items (full-cost pricing).
Reduce subsidies for mining mineral resources.
Increase subsidies for recycling, reuse, and
finding less environmentally harmful substitutes.
Redesign manufacturing processes to use less
mineral resources and to produce less pollution
and waste.
Have the mineral-based wastes of one
manufacturing process become the raw materials
for other processes.
Sell services instead of things.
Slow population growth.
Fig. 15-18, p. 351
16
Specific Resources Their Uses
  • Limestone abundant locally, formed from layers
    of seashells and organisms under pressure as they
    were covered used in sidewalks, fertilizers,
    plastics, carpets, and more
  • Lead used in batteries and cars
  • Clay used to make books, magazines, bricks, and
    linoleum
  • Gold besides being used as money and for
    jewelry, gold is used in medicine (lasers,
    cauterizing agents) and in electronics (circuits
    in computers, etc.)

17
Texas
  • Central limestone, tin, clay, lead, garnets,
    freshwater pearls, amethysts, calcium carbonate
  • West talc, mercury, silver, petroleum, sulfur
  • East lignite coal, petroleum
  • South lignite coal, petroleum, uranium,
    limestone
  • North helium, uranium, petroleum, bituminous
    coal

18
United States
  • Central diamonds (Arkansas), bituminous coal
  • West bituminous and subbituminous coal, gold,
    silver, copper
  • East anthracite coal, bituminous coal
  • South some gold (SC), bituminous coal
  • North bituminous coal, some gold (SD, WI)

19
Primary Sources
Energy Resources
  • Definition the original sources that are used
    to make electricity or heat

20
Secondary Sources
  • Definition the heat and electricity that we use
    for energy

21
Cogeneration
  • Production of two useful forms of energy, such as
    high-temperature heat or steam and electricity,
    from the same fuel source.
  • Ex. An industry using natural gas for
    manufacturing and using the waste heat to produce
    electricity.

22
Fossil Fuels
Examples of Primary Sources
  • Energy conversion chemical to electrical, heat
    or mechanical
  • Only about 30 efficient
  • Benefits easy to use, currently abundant
  • Costs a nonrenewable resource, produces
    pollutants that contribute to acid rain and the
    greenhouse effect
  • Oil- Supplies the most commercial energy in the
    world today. People in the U.S. use 23 barrels
    of petroleum per person or 6 billion barrels
    total each year!!!

23
Core Case Study How Long Will the Oil Party
Last?
  • Saudi Arabia could supply the world with oil for
    about 10 years.
  • The Alaskas North Slope could meet the world oil
    demand for 6 months (U.S. 3 years).
  • Alaskas Arctic National Wildlife Refuge would
    meet the world demand for 1-5 months (U.S. 7-25
    months).

24
OIL
  • Crude oil (petroleum) is a thick liquid
    containing hydrocarbons that we extract from
    underground deposits and separate into products
    such as gasoline, heating oil and asphalt.
  • Only 35-50 can be economically recovered from a
    deposit.
  • As prices rise, about 10-25 more can be
    recovered from expensive secondary extraction
    techniques.
  • This lowers the net energy yield.

25
OIL
  • Refining crude oil
  • Based on boiling points, components are removed
    at various layers in a giant distillation column.
  • The most volatile components with the lowest
    boiling points are removed at the top.

Figure 16-5
26

Gases
Gasoline
Aviation fuel
Heating oil
Diesel oil
Naptha
Heated crude oil
Grease and wax
Furnace
Asphalt
Fig. 16-5, p. 359
27
OIL
  • Eleven OPEC (Organization of Petroleum Exporting
    Countries) have 78 of the worlds proven oil
    reserves and most of the worlds unproven
    reserves.
  • After global production peaks and begins a slow
    decline, oil prices will rise and could threaten
    the economies of countries that have not shifted
    to new energy alternatives.

28
Case Study U.S. Oil Supplies
  • The U.S. the worlds largest oil user has
    only 2.9 of the worlds proven oil reserves.
  • U.S oil production peaked in 1974 (halfway
    production point).
  • About 60 of U.S oil imports goes through
    refineries in hurricane-prone regions of the Gulf
    Coast.

29
Heavy Oils from Oil Sand and Oil Shale Will
Sticky Black Gold Save Us?
  • Heavy and tarlike oils from oil sand and oil
    shale could supplement conventional oil, but
    there are environmental problems.
  • High sulfur content.
  • Extracting and processing produces
  • Toxic sludge
  • Uses and contaminates larges volumes of water
  • Requires large inputs of natural gas which
    reduces net energy yield.

30
Oil Shales
  • Oil shales contain a solid combustible mixture of
    hydrocarbons called kerogen.

Figure 16-9
31
Core Case Study How Long Will the Oil Party
Last?
  • We have three options
  • Look for more oil.
  • Use or waste less oil.
  • Use something else.
  • Estimated that oil will last another 42-93 years

Figure 16-1
32
NATURAL GAS
  • Natural gas, consisting mostly of methane, is
    often found above reservoirs of crude oil.
  • When a natural gas-field is tapped, gasses are
    liquefied and removed as liquefied petroleum gas
    (LPG).
  • Coal beds and bubbles of methane trapped in ice
    crystals deep under the arctic permafrost and
    beneath deep-ocean sediments are unconventional
    sources of natural gas.

33
NATURAL GAS
  • Russia and Iran have almost half of the worlds
    reserves of conventional gas, and global reserves
    should last 62-125 years.
  • Natural gas is versatile and clean-burning fuel,
    but it releases the greenhouse gases carbon
    dioxide (when burned) and methane (from leaks)
    into the troposphere.

34
COAL
  • Coal is a solid fossil fuel that is formed in
    several stages as the buried remains of land
    plants that lived 300-400 million years ago.

Figure 16-12
35

Increasing heat and carbon content
Increasing moisture content
Peat (not a coal)
Lignite (brown coal)
Bituminous (soft coal)
Anthracite (hard coal)
Heat
Heat
Heat
Pressure
Pressure
Pressure
Partially decayed plant matter in swamps and
bogs low heat content
Low heat content low sulfur content limited
supplies in most areas
Extensively used as a fuel because of its high
heat content and large supplies normally has a
high sulfur content
Highly desirable fuel because of its high heat
content and low sulfur content supplies are
limited in most areas
Fig. 16-12, p. 368
36

Waste heat
Cooling tower transfers waste heat to atmosphere
Coal bunker
Turbine
Generator
Cooling loop
Stack
Pulverizing mill
Condenser
Filter
Boiler
Toxic ash disposal
Fig. 16-13, p. 369
37
COAL
  • Coal reserves in the United States, Russia, and
    China could last hundreds to over a thousand
    years.
  • The U.S. has 27 of the worlds proven coal
    reserves, followed by Russia (17), and China
    (13).
  • In 2005, China and the U.S. accounted for 53 of
    the global coal consumption.

38
TYPES OF ENERGY RESOURCES
  • About 99 of the energy we use for heat comes
    from the sun and the other 1 comes mostly from
    burning fossil fuels.
  • Solar energy indirectly supports wind power,
    hydropower, and biomass.
  • About 76 of the commercial energy we use comes
    from nonrenewable fossil fuels (oil, natural gas,
    and coal) with the remainder coming from
    renewable sources.

39
TYPES OF ENERGY RESOURCES
  • Nonrenewable energy resources and geothermal
    energy in the earths crust.

Figure 16-2
40

Oil and natural gas
Floating oil drilling platform
Coal
Oil storage
Geothermal energy
Contour strip mining
Oil drilling platform on legs
Hot water storage
Oil well
Geothermal power plant
Gas well
Pipeline
Mined coal
Valves
Area strip mining
Pipeline
Pump
Drilling tower
Underground coal mine
Impervious rock
Natural gas
Oil
Water
Water is heated and brought up as dry steam or
wet steam
Water
Water penetrates down through the rock
Coal seam
Hot rock
Magma
Fig. 16-2, p. 357
41
TYPES OF ENERGY RESOURCES
  • Commercial energy use by source for the world
    (left) and the U.S. (right).

Figure 16-3
42
REDUCING ENERGY WASTE AND IMPROVING ENERGY
EFFICIENCY
  • Four widely used devices waste large amounts of
    energy
  • Incandescent light bulb 95 is lost as heat.
  • Internal combustion engine 94 of the energy in
    its fuel is wasted.
  • Nuclear power plant 92 of energy is wasted
    through nuclear fuel and energy needed for waste
    management.
  • Coal-burning power plant 66 of the energy
    released by burning coal is lost.

43
USING RENEWABLE SOLAR ENERGY TO PROVIDE HEAT AND
ELECTRICITY
  • A variety of renewable-energy resources are
    available but their use has been hindered by a
    lack of government support compared to
    nonrenewable fossil fuels and nuclear power.
  • Direct solar
  • Moving water
  • Wind
  • Geothermal

44
USING RENEWABLE SOLAR ENERGY TO PROVIDE HEAT AND
ELECTRICITY
  • The European Union aims to get 22 of its
    electricity from renewable energy by 2010.
  • Costa Rica gets 92 of its energy from renewable
    resources.
  • China aims to get 10 of its total energy from
    renewable resources by 2020.
  • In 2004, California got about 12 of its
    electricity from wind and plans to increase this
    to 50 by 2030.

45
USING RENEWABLE SOLAR ENERGY TO PROVIDE HEAT AND
ELECTRICITY
  • Denmark now gets 20 of its electricity from wind
    and plans to increase this to 50 by 2030.
  • Brazil gets 20 of its gasoline from sugarcane
    residue.
  • In 2004, the worlds renewable-energy industries
    provided 1.7 million jobs.

46
Solar
  • Types photovoltaic cells (convert sunlight
    directly to electricity with a 10 efficiency)
    and solar thermal systems (suns heat is used to
    heat bodies of water enough to produce steam that
    can be used to make electricity)
  • Energy conversion radiant/heat to electrical,
    heat or mechanical
  • Benefits pollution-free, unlimited source
  • Costs not useful in cloudy areas or at night,
    we do not have the technology needed to use very
    efficiently

47
Producing Electricity with Solar Cells
  • Photovoltaic (PV) cells can provide electricity
    for a house of building using solar-cell roof
    shingles.

Figure 17-17
48

Single solar cell
Solar-cell roof


Boron enriched silicon
Roof options
Junction
Phosphorus enriched silicon
Panels of solar cells
Solar shingles
Fig. 17-17, p. 398
49
Producing Electricity with Solar Cells
  • Solar cells can be used in rural villages with
    ample sunlight who are not connected to an
    electrical grid.

Figure 17-18
50
Core Case Study The Coming Energy-Efficiency and
Renewable-Energy Revolution
  • It is possible to get electricity from solar
    cells that convert sunlight into electricity.
  • Can be attached like shingles on a roof.
  • Can be applied to window glass as a coating.
  • Can be mounted on racks almost anywhere.
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