Presentation on theme: "OIL Oil is a fossil fuel produced by decomposition of deeply buried organic material such as plants under high temperatures and pressures for millions."— Presentation transcript:
OIL Oil is a fossil fuel produced by decomposition of deeply buried organic material such as plants under high temperatures and pressures for millions of years. Crude oil (petroleum) is a thick liquid containing hydrocarbons that once extracted via drilling are separated into products through fractional distillation (gasoline, aviation fuel, heating oil, diesel oil, asphalt).
Oil Extraction & Processing Crude oil and natural gas are trapped in porous rock beneath dome shaped structures (anticlines). To extract oil, a well is drilled into the deposit. Then oil, drawn by gravity out of the rock pores and into the bottom of the well, is pumped to the surface. Oil is then transported to a refinery by pipeline, truck, or oil tanker.
Oil Recovery Primary Oil Recovery – drilling a well and pumping oil that flows by gravity into the bottom of a well. Secondary Oil Recovery – After primary, water is injected into nearby wells to force some of the remaining oil to the surface. Tertiary Oil Recovery (Enhanced Oil Recovery) – after primary and secondary, CO 2 gas is used to force some of the heavy oil into the well cavity so it can be pumped to the surface.
Distillation Then it is distilled and separated into components with different boiling points. Some of the products called petrochemicals are used as raw materials in industrial organic chemicals, pesticides, plastics, synthetic fibers, paints, and medicines.
Who Has the World’s Oil? The oil industry is the world’s largest business! Eleven OPEC Countries (Organization of Petroleum Exporting Countries) have 78% of the world’s crude oil reserves. Saudi Arabia has the largest (25%) Canada (oil sand) (15%) Iraq (11%) United Arab Emirates (9.3%) Kuwait (9.2%)
How Long Will World Oil Supplies Last? World reserves 80% depleted in 42-93 years. US reserves 80% depleted in 10-48 years. At current rate Saudia Arabia could supply the entire world’s oil needs for 10 years. Reserves under Alaska’s North Slope (Prudoe Bay) would meet current world demand for 6 months and US demand for 3 years. Estimated reserves in ANWR would meet current oil demand for only 1-5 months and US oil demand for 7-24 months.
Advantages of Oil Relatively inexpensive Easily transported via pipelines, trucks and tankers. High net energy yield Ample supply for immediate future Large US government subsidies in place.
Disadvantages of Oil World oil reserves limited and declining. Produces pollution SO 2, NO, NO 2, CO 2 Drilling causes land disturbances which accelerates erosion. Oil spills (Exxon Valdez) Extraction releases contaminated wastewater and brine Disruption to wildlife habitats (ANWR) Artificially low prices encourage waste
Oil Sand Oil sand (tar sand) is a mixture of clay, sand, water and combustible bitumen (heavy oil with high sulfur content). They are dug up by giant shovels, mixed with hot water and steam to extract the bitumen, which is heated and converted to a low-sulfur synthetic crude oil suitable for refining. Exists mostly in Canada (70% known reserves) Severe environmental degradation to air, water and land.
Shale Oil Oil shales contain kerogen which can be extracted from crushed oil shales by heating them to yield a distillate called shale oil. Before it can be sent by pipeline to a refinery, it must be heated to increase its flow rate and processed to remove sulfur, nitrogen, and impurities. Net energy loss Tar Sand - bitumen Shale Oil - kerogen
Natural Gas Natural gas is a mixture of 50-90% by volume of methane (CH 4 ) and smaller amounts of ethane (C 2 H 6 ), propane (C 3 H 8 ), and butane (C 4 H 10 ). Conventional Natural Gas – lies above most reservoirs of crude oil, but can only be used if a pipeline is put in place. Many times it is considered waste and is burned off adding CO 2 to the atmosphere. Liquefied Petroleum Gas (LPG) propane and butane gases liquefied when a natural gas field is tapped. Stored in pressurized tanks for use in rural areas. At very low temperatures LPG can be converted to Liquefied Natural Gas (LNG) can be shipped in refrigerated tankers.
Natural Gas Information Russia has 31 % of world’s gas reserves, followed by Iran (15%), and Qatar (9%). Known reserves and undiscovered potential reserves of conventional natural gas should last the world for 62-125 years. With an increase in consumption of 2% per year, that could be reduced to 80 years!
Advantages of Natural Gas Relatively inexpensive and pipelines in place in USA High net energy yield Produces less air pollution than other fossil fuels Extraction not as harmful as for oil and coal Easily processed and inexpensive to transport Can be used in fuel cells Can be used in combine-cycle natrual gas systems (cogeneration) Viewed as “transitionary fossil fuel” as world switches to alternative energy resources.
Disadvantages of Natural Gas H 2 S and SO 2 released during processing, and CO 2 and hydrocarbons during burning. LNG processing is expensive, dangerous, and results in lower net energy yield Leakage of pipes and tanks (CH 4 ) contributes to global warming Extraction releases contaminated wastewater and brine Land subsidence Disruption to wildlife habitats (ANWR)
Another Note on Global Warming Subsidies for oil and gas encourage high use of the energy resource and discourages conservation. Oil and gas are considerably cheap (10-12 cents per kwh) The Earth Summit, June 1992 “UN Conference on the Environment” Issue #1 - Climate Change Treaty – A treaty to curb CO2 emissions, thereby reducing global warming. More than 165 nations signed the treaty and is now considered legally binding. President Clinton signed in 1993. Congress failed to approve it and it has not been ratified since in the US. Kyoto – Bush refuses to sign “Bad for Economics”.