Transcript Environmental Studies

ENERGY AND MINERALS
Lecture 9
Energy and
Minerals
Mineral
- A mineral is any naturally occurring inorganic
substance or element found in the Earth’s crust
- The word rock refers to solid mineral deposits
- An ore is rock that contains a large proportion of a
particular mineral, making it profitable for mining
or extraction.
Types of Minerals
- Metals are minerals e.g. iron, aluminium
and copper, which are malleable, lustrous
and good conductors of heat and electricity.
- Non-metallic minerals lack these
characteristics e.g. sand, stone, salt and
phosphates.
Uses of Minerals
- many can be extracted & converted into useful
materials
For example:
- aluminium is used to make cars & airplanes
- steel is an essential building material
- copper is used for electrical &
communication wiring
- sulphur is used to make plastics & refine oil
Jamaica’s Bauxite Resource
Mining
- the various processes whereby minerals are
extracted
The 2 main types of mining are:
• Sub-surface Mining
• Surface Mining
Mining
• Sub-surface Mining
- extraction of a metal ore or fuel resource
from a deep underground deposit
• Surface Mining
- removal of soil before extracting a mineral
deposit found fairly close to the earth’s surface
Mining
Overburden
- layer of soil and rock overlying mineral deposit
- removed during surface mining
Mining
Spoil
- unwanted rock and other waste material
produced when a material is removed from the
earth’s surface or subsurface.
Environmental Implications of
Bauxite Mining in Jamaica
Extraction
- Mining involves deforestation
- Noise pollution
- Dust pollution
Environmental Implications of
Bauxite Mining in Jamaica (Cont’d)
Deforestation
- Habitat
destruction
- Soil erosion
- Sedimentation of rivers
- Smothering of aquatic habitats
Processing Bauxite
This involves smelting – melting the ore at
high temperatures to help separate impurities
from the molten metal.
If air pollution control devices are not installed,
many dangerous gases are emitted during
smelting.
Environmental Implications of
Bauxite Mining in Jamaica (Cont’d)
Processing
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Processing and disposal of minerals
pollute the air, soil and water.
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Rio Cobre polluted to the point where fish
kills observed
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Air pollution implicated in roof damage,
fence damage
www.pollutionissues.com/Li-Na/Mining.html
Possible Chemical Contaminants
of Mine Wastewaters
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Cyanide
Lead
Mercury
Nickel
Nitrate
Radon
Sulphur-based compounds
Environmental Implications of
Bauxite Mining in Jamaica (Cont’d)
Solutions
-
Construct marshes or ponds downstream from
mines.
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When a mine is abandoned, the land can be
reclaimed, or restored to semi-natural conditions
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New disposal method for red mud
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Install expensive pollution control devices to
smelters
Fossil Fuel
- Product of partial or complete decomposition of
plants and animals that occur as crude oil, coal,
natural gas, or heavy oils
- Formed as a result of exposure to heat and
pressure in the earth’s crust over millions of years
- non-renewable, exhaustible resource
Nuclear Energy
- energy released when atomic nuclei undergo a
nuclear reaction, such as nuclear fission or
nuclear fusion
Alternate Energy Sources
Renewable energy sources are sources of energy that
are replenished by natural processes so that they can
be used indefinitely. They include:
 Direct Solar Energy
 Wind Energy
Hydropower
Ocean Thermal Energy
Geothermal Energy
Tidal Energy
Alternate Energy Sources
in Jamaica
Renewable energy sources account for only 9% of energy mix.
- Projected to reach 20% by 2030 (Renewable energy policy)
- 23 wind turbines of 20.7 MW capacity commissioned at
Wigton wind farm in Manchester in May 2004.
Facility upgraded to generate 38.7 MW in 2011
- New 3MW wind power facility commissioned by JPS
at Munro in St. Elizabeth in Oct 2010.
- 6.4 MW expansion of the hydro-electricity facility
at Maggotty in St Elizabeth planned to begin Sept 2011.
Energy Conservation
Energy conservation is moderating or
eliminating wasteful or unnecessary energyconsuming activities.
Energy efficiency is using technology to
accomplish a particular task with less energy.
Waste Management
Solid Waste
- Any unwanted or discarded material that is
not a liquid or a gas
- It is estimated that approximately 1 billion
tonnes of waste is generated across the island
annually.
- 70% collected
- Half is generated in the Riverton wastershed.
Types of Solid Waste
• Municipal Solid Waste
- solid materials discarded by homes and
businesses in or near urban areas
• Non-municipal Waste
- includes waste from mining, agriculture,
industry
HOW TO GET RID OF SOLID WASTE
• dump
• bury
• burn
• recycle
Open Dumps
- unsanitary
- malodorous
- methane gas released as wastes decompose
- fire pollutes air with acrid smoke
- hazardous wastes leach into groundwater
Sanitary Landfills
- wastes are spread out in thin layers, compacted
and covered daily
- lined with clay and plastic before being filled
with garbage
- open burning is discouraged
- methane gas is collected and burned to produce
steam or electricity
Sanitary Landfills cont’d
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Incineration
- kills germs
- reduces the volume of waste going into landfills
by ~ 60%
- puts toxic substances
into the atmosphere
- the amount of material to be buried is greatly
reduced but its toxicity is increased
Recycling
- collecting and reprocessing a resource so that it
can be made into new products
Composting
Compost
- a sweet-smelling, dark-brown humus that is rich
in organic matter and soil nutrients
- produced by mixing biodegradable solid waste
with soil
Recycling in the Caribbean cont’d
Advantages
Disadvantages
• Reduces the amount of
garbage going to landfills • Takes energy to recycle
materials
• Saves energy
• Reduces pollution
PROPER SOLID WASTE
MANAGEMENT
• REUSE – using a product more than once, either
for the same purpose or for an alternate purpose
e.g. refillable glass bottles.
• REDUCE – decrease in the amount of solid
material used through proper design in
manufacture and decreased actual use by
consumer
• RECYCLE – collect and reprocess many
materials found in solid waste into new products
of the same or different type.
Legislation
The National Solid Waste Management Act was
passed in 2001.
- The National Solid Waste Management Authority
was established in April 2002.
- The public cleanliness regulations were drafted
and gazetted in 2003.
Legislation
- The penalty for throwing, dropping or otherwise
depositing and leaving any litter in any public place is
$2,000
- The penalty for willfully breaking any bottle or any
glass or any article made of glass in, or, on any public
place without lawful authority is $5,000
- The penalty for employing or recruiting person(s)
who erect, display, deposit or affix anything in a
public place or on any building, wall, fence or
structure is $10,000.