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Energy and Resources

Chapters 23, 19, 20, 21. Energy and Resources. Minerals and Mining. Chapter 23 . Rocks provide the minerals we use Rocks are a solid aggregation of minerals Minerals are naturally occurring solid chemical elements or compounds Mining is used to obtain minerals Fossil fuels, groundwater??

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Energy and Resources

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  1. Chapters 23, 19, 20, 21 Energy and Resources

  2. Minerals and Mining Chapter 23

  3. Rocks provide the minerals we use • Rocks are a solid aggregation of minerals • Minerals are naturally occurring solid chemical elements or compounds • Mining is used to obtain minerals • Fossil fuels, groundwater?? • Most minerals are in low concentrations, so scientists attempt to find concentrated sources of minerals before mining begins • Metals can be extracted within ore • Metals are elements that are typically lustrous, opaque, malleable conductors • Most metals are not found in a pure state, but are found within an ore (a grouping of minerals) • Common economically valuable metals: copper, iron, gold, aluminum • Metals need to be processed to separate them from the ore and make them ready for use • Chemical or physical removal • Smelting • Harmful byproducts? • Tailings Mineral Resources

  4. We also mine/use many non-minerals • Construction Materials: Sand, gravel, • Fertilizers: phosphates, • Other economic value: limestone, salt, potash, diamonds • Fuels: Uranium, • Fuels that are not technically minerals: coal, petroleum, natural gas, oil sands, oil shale, methane • Conflict over mining products • “blood diamonds” Mineral Resources

  5. Mining makes a huge contribution to the economy • $57 B in raw materials (2009) • $454 B in processed materials (2009) • 1.2 million jobs • Mining exerts a huge impact on the environment! • Strip mining • Subsurface mining • Open Pit mining • Placer mining • Mountaintop mining • Solution mining • Ocean mining Mining Methods https://www.youtube.com/watch?v=ioqauAoZwVY

  6. Types of mining (Descriptions and impacts)

  7. Types of mining (Descriptions and impacts)

  8. Types of mining (Descriptions and impacts)

  9. Types of mining (Descriptions and impacts)

  10. Types of mining (Descriptions and impacts)

  11. Types of mining (Descriptions and impacts)

  12. Mining companies are required to restore sites when finished (in the United States) • Reclamation • Removal of buildings and structures • Soils: biotic potential? • Waters: drainage and reclamation • Policies • General Mining Act of 1872 • Hardrock Mining and Reclamation Act of 2009 • Mineral Leasing Act of 1920 Can mining impacts be regulated or reversed?

  13. Non-renewable resource in limited supply • Economically recoverable mining • Technically recoverable mining • How long will deposits last? • Discovery of new reserves • New extraction technologies • Changing pressures from society, technology, and consumers • Recycling • Gold versus Platinum • E-waste Sustainable Mineral Use

  14. There’s No Tomorrow http://www.youtube.com/watch?v=VOMWzjrRiBg 0:00-7:10 Introduction

  15. Fossil Fuels, Their Impacts, and Energy Conservation Chapter 19

  16. Since the Industrial Revolution, our main source of energy has been: Sun  Photosynthesis  Fossil Fuels • Fossil Fuels (Coal, Oil, Natural Gas) • High energy content allows for • Shipping • Burning • Storing • Used for • Transportation • Heating/Cooking • Electricity (secondary form of energy that can be transported over long distances) • Others • Geothermal • Tides • Nuclear Energy • Biomass • Solar, • Wind Sources of energy

  17. Graph the global consumption of fossil fuels over the past 50 years

  18. Come from fossils • Depends upon • Starting material • Temperature and pressure • Anaerobic decomposers (Aerobic versus Anaerobic decomposition) • Time • Because of all these factors, deposits for FF are unevenly distributed • Developed Nations consume more than Developing Nations (20% by United States) Fossil Fuels

  19. Net energy expresses the difference between energy returned and energy invested • EROI (Energy Returned on Investment) • EROI= Energy returned/Energy invested • The higher the EROI ratio, the more energy we get per unit we invest • Oil and natural gas were 100:1 in 1940, 30:1 in 1970 and are about 5:1 now….WHY? It takes energy to make energy

  20. Most abundant fossil fuel • Hard, dark substance that form from organic matter (almost always woody plant matter) that gets compressed under high pressure where little or no decomposition has taken place • Starts as peat and them becomes coal • Deposition mostly occurred 300-400 million years ago in swampy environments • The high pressure of formation results in a dense, solid carbon structure • Has been used by humans for thousands of years, but demand began increasing with the start of the steel industry (1875) • Provides 50% of electrical energy in the US • China (39%) and US (16%) are the primary producers • China (39%) and US (15.5%) are the primary consumers Coal

  21. We extract coal by • Strip mining • Subsurface mining • Mountaintop removal mining • Types of coal (changes in water, carbon, and energy content) • Lignite (least compressed=less carbon=less energy per unit volume) • Sub-bituminous • Bituminous • Anthracite (most compressed=more carbon=more energy per unit volume) • Coal can also vary in its impurities = important for reducing pollution • We get energy from coal by • Combusting (burning) coal to convert water to steam which turns a turbine Coal

  22. Versatile and clean-burning compared to other fuels (emits ½ the carbon or coal and 2/3 the carbon of oil) Consists of methane and other hydrocarbons Uses: heating our homes, electricity At low temps (in a liquid state) it can be shipped long distances Russia (21%) and US (19%) are the largest producers US (21%) and Russia (15%) are the largest consumers At current rates of use, we have about 60 years left Natural Gas

  23. Formation • Biogenic gas: shallow, anaerobic decomposition • swamp gas • gas from landfills • Thermogenic gas: deep underground compression • Kerogen: can form natural gas and crude oil, most gas is found above oil or coal • Most commercially extracted gas is thermogenic • Coalbed methane: commonly leaks out during mining processes • Miners now try to trap and use this gas or burn it off (called flaring) Natural Gas

  24. Gas naturally moves upwards because of pressure underground and its low molecular weight • Because we have already mined so much gas, many sites now require gas to be pumped to the surface with a “horsehead pump” • Fracturing techniques (known as “fracking”) break into rock formations using water under high pressure, hold the crack open with sand or glass beads, and extract the gas • This process bring up many concerns! fracking

  25. Natural gas (13%) and oil (1/3) come from the Gulf of Mexico and southern California coast • Drilling into the seafloor on the continental shelf (this is where more of the remaining resources probably are) • Platforms must withstand wind, waves, currents • Some actually float • Potential Issues? • Moratorium on offshore drilling lifted in 2008 and then expanded in 2010 • Deepwater Horizon • Backtracking and stoppage of new approvals Offshore Drilling

  26. Oil is our most used fuel, accounting for 35% Used since 1854 (Pennsylvania) Crude Oil (a sludgelike liquid) usually forms 1.5-3km below the surface from dead plant material trapped under marine waters millions of years ago (just like natural gas) Globally, 200 gallons are used per person Use has increased 15% in the last decade and does not show signs of slowing (US, China, India) Russia (12%) and Saudi Arabia (12%) are the largest producers (followed by US at 10%) United States (22%) and China (10%) are the largest consumers Oil/Petroleum

  27. Geothermal heating allows crude oil to migrate up through rock pores and collect in layers • Geologists search for oil by drilling, using seismic surveys, and mapping underground rock formations • These methods have estimated that 11.6-31.5 billion barrels of oil lay beneath the Arctic National Wildlife Refuge, of which 4.3-11.8 are recoverable currently • Proven Recoverable Reserve • Technology determines what can be extracted • Market Price determines how much will be extracted How do we get oil? • Drilling extracts oil • Exploratory Drilling • Primary Extraction: Oil rises on its own from pressure • Secondary Extraction: 2/3 of oil may remain trapped, solvents and/or water and steam are used • $$$$$ • Not everything can be removed with our current technology

  28. Petroleum products • Separation of components of crude oil (based on size of hydrocarbon chains) must take place at a refinery • Heating, cooking, transportation, asphalt, plastics, lubricants, fabrics, pharmaceuticals, fertilizers, pesticides Uses of oil

  29. Estimates are that we have used around ½ of the world’s oil reserves • Reserves-to-production ratio (R/P ratio) • Total remaining reserves/annual production rate • 1.2 trillion barrels/30 billion barrels = 40 more years • When should we start to worry? • When we run out • “Peak Oil”……now • Hubbert’s Peak • Should we worry? • Suburbs as slums of the future • Conservation of energy and alternative energy soruces Are we running out of oil?

  30. Sand and clay that contain 1-20% bitumen, a thick form of petroleum Too thick to extract conventionally, so strip mining is often used at the surface Deposits more than 75m below ground are removed using steam injection or chemical solvents After extraction, it must be sent to a refinery that can upgrade the fuel by adding hydrogen and removing carbon ¾ of deposits are found in Venezuela and Alberta (may almost as much in Canada as oil in Saudi Arabia) Oil Sands (Tar Sands)

  31. Sedimentary rock filled with kerogen (organic matter) that can be processed to produce liquid petroleum Forms through the same process as oil, but not buried deeply enough Mined through strip mining or subsurface mines It can be burned like coal or baked to extract liquid petroleum 40% of world reserve is found in US west High fuel prices are attracting people to oil shale Oil Shale

  32. Found in sediments on the ocean floor • Is stable at these conditions (temperature/pressure) • Formed by anaerobic decomposition and thermogenic formation below the surface • There are immense amounts available, but we do not know how to extract them safely • Release of gas that could cause landslides/tsumani/global warming Methane Hydrate

  33. Low EROI • 2:1 or 3:1 for oil shale • 5:1 for crude oil • Environmental impacts • Strip mining that devastates landscapes • Pollution of waterways • Non-recovered areas • Emissions • Carbon dioxide, methane, air pollutants Drawbacks of alternative fuels

  34. Pollution • Air: Irritants, carcinogens, asphyxiation, poisons, photochemical smog, bioaccumulation • Water: Mostly non-point source problem, although we usually hear about the point source problems in the news • Exxon Valdez (1989) • Cars, homes, industry, gas stations ….. All create runoff that can contaminate waterways and groundwater (drinking water) • Drive climate change • Retired carbon from long-term reservoir underground and release it into the air • Carbon from the fuel combines with oxygen in the air to form Carbon Dioxide • Methane is also a powerful greenhouse gas • Alters the environment • Acid drainage from coal mining • Road networks • Infrastructures Impacts of Fossil Fuels

  35. Clean coal technologies • Techniques that aim to remove chemicals during the process of generating electricity from coal • Scrubbers • Dry coal • Gasification (syngas) • Carbon capture and carbon storage (sequestration) • Capturing emissions, converting the gas to a liquid and then storing it in the ocean or underground in rock • Mattoon, Illinois • Will it stay underground? • Will it trigger earthquakes? • Will it contaminate groundwater? • Will it acidify the ocean? • Will it prolong our dependence on diminishing fossil fuels? • Directional Drilling Solutions?

  36. Political Issues • National can become dependent on foreign energy • OPEC (Organization of Petroleum Exporting Countries) • Economic Issues • Supply and prices can change economies of nations • Strategic Petroleum Reserve • Social Issues • Local people may or may not benefit from reserves Issues

  37. Option 1: Use it until its gone • Option 2: increase funding to develop energy alternatives to start a rapid shift • Option 3: middle group, reduce our dependence gradually • Energy efficiency: get more and use less • Energy conservation: use less • Cars • Café Standards (corporate average fuel efficiency standards) • Low taxes on gas in US • Cash for Clunkers • Personal choice • Increased efficiency • Cogeneration Conversion to renewable energy?

  38. There’s No Tomorrow http://www.youtube.com/watch?v=VOMWzjrRiBg 7:10-12:01 Oil, Coal, Natural Gas

  39. Conventional Energy Alternatives: Nuclear energy, bioenergy, hydroelectric power Chapter 20

  40. Play a minor yet substantial role in energy and electricity budgets today • Fuelwood and Biomass= 10% • Nuclear= 6% • Hydropower= 2% • Less impact that fossil fuels, but more than renewable alternatives • Growth in use is slower than with fossil fuels Conventional energy alternative

  41. What’s its reputation? • No air pollution  • Radioactive waste  • Accidents  • Commonly used in US (20%), France (76%), and Japan • How does it work? • Fission (splitting of atoms) releases nuclear energy • Energy (heat, light, radiation) is converted into thermal energy and use to generate electricity • Must use large, heavy atoms like uranium-235 (which is not a renewable resource) Nuclear power

  42. If not controlled, the chain reaction of nuclear fission would start a positive feedback loop releasing enormous amounts of energy (like an atomic bomb) • Nuclear reactors control this reaction inside power plants • Process: -Mining: Only 1% of naturally occurring uranium is U235, so the more common U238 must be processed to be at least 3% U235 -Usage: enriched uranium is formed into metallic tubes called fuel rods, moderators and control rods make sure that the reaction takes place at the desired rate -Storage: after enough uranium has decayed, energy generation is no longer adequate, so the fuel rods must be replaced Nuclear power

  43. Benefits • No air pollution • Emissions 4-150 times less than fossil fuel combustion • Less chronic health risks and safer work environments • Less mining=less damage to landscapes Risks • Radioactive waste disposal • Waste will emit radiation for thousands of years • Waste used to be dumped into the oceans in barrels, now it is held in temporary storage at power plants • Yucca Mountain • Potential for dangerous accidents • Three Mile Island and meltdowns • Chernobyl Overall, growth has slowed, new plants aren’t really being built Risks and benefits of nuclear energy

  44. Breeder reactors • Use U238, which usually goes unused as a waste product • 99% of all uranium is U238, so it makes better use of fuel, makes more power, and produces less waste • Can be more dangerous because sodium (rather than water) is used as a coolant • Are more expensive • Create plutonium as a byproduct, which can be used in nuclear weapons • Fusion • Same process that drives the sun • Forces nuclei of lightweight elements together • Difficult to do without very high temps (millions of degrees) • Requires more energy input than output at this point (EROI of less than 1) New ideas

  45. Organic materials derived from living or recently living organisms contains chemical energy from photosynthesis • Wood, charcoal, manure • Used widely in the developing world • Renewable with no net release of carbon dioxide, but it is hard to just the renewability of the resource • Biopower can be used in the same way as coal to generate power for electricity, or as a liquid fuel for cars Bioenergy/biomass energy

  46. Waste products (mostly burned) • Forestry industry, pulp mills, paper mills • Agricultural waste (cornstalks, corn husks) • Animal wastes • Organic waste from landfills • Bioenergy crops (mostly used for liquid fuels) • Fast-growing grasses and trees • Combustion strategies • Co-firing • Gasification • Scales of production • Advantages • Reduction of emissions of some pollutants • Resources more evenly spread out • Disadvantages • Depriving soil of nutrients Sources of bioenergy

  47. Ethanol • Ethanol is produced from fermentation and is added to gas to reduce emissions (any car can run on up to 10% ethanol) • 1990 Clean Air Act • Flex-fuel vehicles • This may not be a sustainable energy choice • Overuse of land to grow crops • Competition with food production drives up food prices • Low EROI 1.5:1 Biodiesel • Produced from vegetable oils, used cooking grease, or animal fat • Fat is mixed with small amounts of ethanol or methanol in the presences of a catalyst • Diesel engines can run on 100% biodiesel, but a 20% mix is more common • Lower emissions and competitive prices • Biotour • Some environmental impacts from growing these crops Ethanol AND Biodiesel in cars

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