FOSSIL FUELS OIL AND NATURAL GAS PART II
Oil • Buried organic matter rich in • Hydrocarbons
Reserves of oil • Enormous oil fields containing more than half of the world’s total estimated reserves are situated in the Persian Gulf region, which include Iran, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, Syria, United Arab emirates, and Yemen. In addition major oil fields are known to exist in Venezuela, Mexico, Russia, Kazakhstan, Libya, and the United States (Alaska and the Gulf of Mexico)
Petroleum Refining Crude oil is separated into a variety Of products based on their different Boiling points. The lower the boiling Point, the higher the compounds rise In the water. Oil is also used to produce Petrochemicals, compounds in such Diverse products as fertilizers, plastics Paints, pesticides, medicines, and Synthetic fibers.
Reserves of Natural Gas • Almost half of the world’s proved recoverable reserves of natural gas are located in Russia and Iran. The United States has more deposits of natural gas than Western Europe. • Canada and United States also extract coal bed methane, a form of natural gas associated with coal deposits.
Natural Gas • Natural gas contains only a few different hydrocarbons: methane and smaller amounts of ethane, propane, and butane. Propane and butane are separated from the natural gas, stored in pressurized tanks as liquid called liquefied petroleum gas. Used • Primarily as fuel for heating and cooking in rural areas. • To heat residential and commercial buildings. • To generate electricity in power plants. • For a variety of purposes in the organic chemistry industry.
Use of natural gas • Generation of electricity • Transportation • Commercial cooling
Cogeneration • Cogeneration, in which natural gas is used to produce both electricity and steam; the heat of the exhaust gases provides the energy to make steam for water and space or industrial heating. • Cogeneration systems that use natural gas provide relatively clean and efficient electricity.
Advantages of natural gas • Natural gas vehicles emit 80 to 93% fewer hydrocarbons, 905 less carbon monoxide, 905 fewer toxic emissions, and almost no soot. • Cleaner to burn • Half as much CO2 as coal • More efficient • 10% energy lost • 60-year supply at current rates
Disadvantages of Natural Gas • The main disadvantage of natural gas is that deposits are often located far from where the energy is used. Because it is a gas and less dense than a liquid, natural gas costs four times more to transport through pipelines than crude oil. • To transport natural gas over long distances, it must first be compressed to form liquefied natural gas (LNG) then carried on specially constructed refrigerated ships. • Can be polluting, dangerous when extracted.
Structural traps • Underground geologic structures that tend to trap any oil or natural gas if it is present
Global Oil Demand and Supply • In 2006 North America and Europe consumed 50% of the world’s total petroleum, yet these countries produced only 22.9% of the world’s crude oil. • In contrast, the Persian Gulf region consumed 5.9% of the world’s petroleum and produced 27.9% of world’s crude oil. • Persian Gulf Region has much higher proven reserves than any other countries.
Environmental Impacts of Oil and Natural Gas. • Two sets of environmental impacts: one with the use and the other involved in production and transport. • Carbon dioxide emissions from the burning of oil and natural gas. • Change in global climate change. If the change is rapid it could be catastrophic. • Acid deposition. Oil does not produce much of sulfur oxides, it does produce nitrogen oxides, mainly through gasoline combustion in automobiles. • Nitrogen oxides along with unburned gasoline vapors, results in photochemical smog. • Poorly tuned engines and diesel-burning vehicles contribute to particulate matter- cause lung damage and disease.
Environmental impacts of natural gas • Burning of natural gas does not pollute the atmosphere as much as the burning of oil. It is a clean efficient source of energy that contains no sulfur, a contributor to acid deposition. It produces less carbon dioxide, fewer hydrocarbons, almost no particulate matter. • Main concern is the environmental damage that may occur during their transport, often over long distances by pipelines or ocean tankers. • A serious spill along the route creates environmental crisis, particularly in aquatic ecosystems, where oil slick can occur. • One of the worst oil spills in Europe’s history occurred in 2002 when a storm caused the oil tanker Prestige to break up off the coast of Spain. It brought large fishing industry into a halt there
The Largest Oil Spill in the United States. In 1989, Exxon Valdez hit Bligh Reef and Spilled 260,000 barrels (10.9 million gallons Of crude oil into Prince William Sound along the coast of Alaska, creating the Largest oil spill in U.S history.
Effects of Exxon Valdez Oil Spill • Contaminated hundreds of square kilometers of shoreline. • Report from the Alaska Department of Environmental Conservation – more than 30,000 birds (sea ducks, loons, cormorants, bald eagle), 3500 and 5500 sea otters died as a result of the oil spill. • Killer whale and seal population declined. • Salmon migration disrupted. • No fishing season that year.
Clean up effort • Scientists advised both Exxon corporation and the • government regarding clean up. • 12,000 workers took part in the cleanup • Mechanized steam cleaning and rinsing, which killed • Shoreline organisms like barnacles, clams, mussels, eelgrass • And rockweed. • Despite cleanup it has left behind contaminated • Shorelines and damage to some species of birds • Fishes such as murrelet and rockfish and seal and • A reduced salmon catch. • In 1991, Exxon agreed to pay $1 million to Alaska
Oil Pollution Act of 1990 • This legislation establishes liability for damage to natural resources resulting from a catastrophic oil spill, including a trust fund that pays to clean up spills when the responsible party cannot, a tax on oil provides money for the trust fund. • This requires double hull on all oil tankers that enters U.S. waters by 2015. Exxon Valdez did not have double hull.
The Largest Global Oil Spill • The worlds massive oil spill occurred in 1991 during the Persian Gulf War. • About 6 million barrels of crude oil were dumped into the Persian Gulf. Many oil wells were set on fire and oil spilt into the desert around the burning oil wells. • Celanup efforts along the coastline and the desert were hampered by the war. • 1n 2001, Kuwait began a cleanup operation and yet not completed.
Read Case in PointPage Number 250 • Give your thoughts on oil exploration in the Arctic National Wildlife Refuge
Oil in Ecuador • Ecuador 2nd largest S. America producer • 70% of exports • Drilling in Amazon rainforest
Synfuels • A liquid or gaseous fuel that is synthesized from coal and other naturally occurring resources and used in place of oil or natural gas. • Synfuels include tar sands, oil shales, gas hydrates, liquefied coal, and coal gas. • Synfuels are more expensive to produce than fossil fuels, they may become more important as fossil fuel reserves decline.
Tar sand or oil sands • These are underground sand deposits permeated with bitumen, a thick asphalt like oil. The bitumen in tar sands deep in the ground cannot be pumped out unless it is heated underground with steam to make it more fluid. If tar sands are close to Earth’s surface, they are surface-mined. Once bitumen is obtained from tar sand, it must be refined like crude oil. • Major tar sands are found in Venezuela, and in Alberta, Canada, where an estimated 300 billion barrels of oil occur in tar sands. • Canadian mines are currently producing almost 300 billion barrels of oil a year from oil sands.
Oil Shales • These are sedimentary rocks containing a mixture of hydrocarbons known collectively as kerogen. Oil shales are crushed and heated to yield their oil, and kerogen must be refined after it is mined. • This is not cost efficient because the mining and refining requires a great deal of energy. • Location: Australia, Estonia, Brazil, Sweden, The United States, China, Wyoming, Utah, Colorado.
Gas hydrates or methane hydrates • These are reserves of ice encrusted natural gas located deep underground in porous rock. Location: Arctic Tundra, deep under permafrost, and in the deep-ocean sediments of the continental slope and ocean floor. • Most deposits are too small to be removed economically.
Coal liquefaction • A nonalcohol liquid fuel similar to oil can be produced from coal. The liquid fuel, which is cleaned before burning, is less polluting than solid coal. This process is called coal liquefaction.
Coal gasification • It is the production of the combustibile gas methane from coal by reacting it with air and steam. • Advantage: coal gas burns almost as cleanly as natural gas. Scrubbers are needed. It is expensive to produce.
Environmental impacts of Synfuels • Emission of carbon dioxide and other pollutants. • Contributing to global warming and air pollution. • Synfuels like coal gas require large amounts of water during production. • Enormously large areas of land would have to be surface mined to recover the fuel in tar sands and oil shales.
The U.S Energy StrategyPage number 254-255 • Increase energy efficiency and conservation. • Secure future fossil fuel energy supplies • Develop alternative energy sources. • Learn about National Energy Policy and the Energy Policy Act of 2005. • Read “You can make a Difference” in page number 254. you can also add more to it. • Discussion: Highlights of President George W.Bush’s National Energy Policy.
Additional information • Refer Environment by J. Withgott • Case Study-Oil or Wilderness on Alaska’s North Slope. • Generation of electricity from coal. • Extraction of oil. • Carbon Sequestration. • Predicting environmental impacts of oil drilling on Alaska’s North slope. • Reliance on fossil fuels –cause and consequences
Environmental Science By Friedland • Energy flow chart for the United States. • Math problem • Advantages and disadvantages of petroleum, natural gas. • The Hubbert Curve