360 likes | 571 Views
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
E N D
ENERGYAND 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
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 soilbeforeextracting 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 andother 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 - Processing and disposal of minerals pollute the air, soil and water. - Rio Cobre polluted to the point where fish kills observed - Air pollution implicated in roof damage, fence damage www.pollutionissues.com/Li-Na/Mining.html
Possible Chemical Contaminants of Mine Wastewaters • 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. - When a mine is abandoned, the land can be reclaimed, or restored to semi-natural conditions - New disposal method for red mud - Install expensive pollution control devices to smelters
Fossil Fuel • Product of partial or completedecomposition 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 energy-consuming activities. Energy efficiency is using technology to accomplish a particular task with less energy.
Waste Management Solid Waste - Any unwanted or discardedmaterial 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 businessesin or nearurban 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
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
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.