Unit 2: Understanding Common Energy Conversion Systems. Lesson Objectives: Introduction. Lesson

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1 Unit 2: Understanding Common Energy Conversion Systems Lesson 7 - The Formation & Extraction of Fossil Fuels Approximate Lesson Length: 3hours Save your assignment as: SCI24U2L7 Lesson Objectives: Upon completion of this lesson the student will be able to: learn when and how fossil fuels were formed; study how the importance of different fuels has changed. learn how fossil fuels are extracted; describe the processes used to locate and extract oil; study how crude oil is refined. Lesson Links Please click on any of the links below to take you to the specific section of the lesson. Formation of Fossil Fuels Extraction of Fossil Fuels Lesson Review Assignment Introduction We have already discussed the importance of electricity in our lives. In Alberta, the primary source of our energy production comes from coal. Our society is also very dependent on motor vehicles which require fossil fuels. In today's lesson, you will learn about fossil fuels and how we use them for our energy needs. You will also learn how fossil fuels such as coal, crude oil, and natural gas were developed from the remains of ancient forests and long-dead marine life. Back To Top Lesson file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (1 of 6)19/10/2008 7:26:00 PM

2 Formation of Fossil Fuels Fossils showed early scientists that plants and animals, unlike any that now live on Earth, did live here long ago. Not surprisingly, knowledge of the locations of fossil deposits often provides clues to the location of coal, oil, and gas deposits but not always. In fact, coal and oil companies spend millions of dollars locating and assessing possible deposits. Initially, geologists and other scientists look for certain rock formations. Millions of years ago, the remains of ancient swamp vegetation got covered by layers of sediment. This created heat and pressure changing the organic matter into coal, oil and natural gas. When searching for oil and gas, seismic teams head the search for promising sites. Once these are identified, drilling companies start with exploratory drilling. Once the location of a field has been identified, more holes are drilled. In Alberta, the surface above many oil fields is not that noticeable except for the pump jacks, which are often sitting at the edge of farm properties or pastures bringing oil to the surface. Pump jacks bring the oil into storage containers located nearby. Trucks empty the storage containers and transport the oil to nearby refineries. Please refer to figure 8.1 on page 136 to learn how coal was formed. Let's review... There are three types of coal found in Alberta: lignite, sub-bituminous, and bituminous. Sub-bituminous coal is used to generate most of our province's electricity. file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (2 of 6)19/10/2008 7:26:00 PM

3 Back To Top Extraction of Fossil Fuels Mining Coal When coal is near the surface, open-pit techniques are used. Large shovels remove the overburden. The exposed coal is blasted to break it up and shoveled into large trucks or haulers. Underground mining involves excavating coal from deep sources underground. Shafts are dug down to the coal, or seams that show at the surface are followed underground. Miners use drills and explosives to break up the coal. Coal is brought to the surface in small trains, in shuttle cars, or by conveyor belts. Refer to figure 8.5 on page 139 to see how land reclamation works. Land reclamation involves the following steps: 1. Remove and store the topsoil before strip mining begins. 2. When the coal has been depleted, use tractors and scrapers to level ridges and grade the mining area. 3. Bring back the topsoil and spread it out using graders. 4. Use fertilizer and quick-growing plants to prepare the land for farming, pasture, or wildlife habitat. When these steps were omitted in the past, an empty scar was left where nothing could grow or survive. Oil Underground Oil is found in microscopic pores between the particles that make up rocks. Over time, changes in Earth s crust caused great amounts of pressure that forced the tiny oil droplets into porous rock called reservoir rock. Further movements of Earth s crust helped to trap oil and natural gas in sections of reservoir rock that are located between layers of impermeable rock. Geologists use a number of technologies to determine the location of potential oil and natural gas reservoirs. One of the more common methods is the use of a seismic survey. During this type of survey, shock waves from compressed air guns, thumper trucks, or explosives are sent through the layers of Earth s crust. The returning sound waves reflect off rock, are detected by sensitive equipment, and used to create images of the underground rock layers. Geologists interpret these images and other data looking for structures that may contain oil and natural gas. Extraction involves setting up a drilling platform and drilling for oil. Once the oil site has been confirmed, jack pumps move the oil to large oil storage containers. (Refer to figure 8.7 on page 140) By looking at figure 8.7, you can see why natural gas is found where oil is located. In the past natural gas was not used as it is today because of the dangers involved in transporting it safely. Nowadays, there are pipelines across Canada to transport natural gas and trucks and ships have been developed to transport it safely. Fractional Distillation - In an oil refinery, a process called fractional distillation is used refine petroleum. Crude oil is heated in a series of heat exchangers to remove water and salt. It is then sent to a furnace, where further heating occurs. The hot oil is then sent to the distillation tower. The inside of the distillation tower is very hot at the bottom; the temperature gradually cools toward the top of the tower. Each component of crude oil has a unique boiling point. In the distillation tower, perforated plates are fitted with bubble caps. As each component reaches a point where the temperature is just below its boiling point, it condenses. The vapours are sent to condensers, where they are liquefied. Note that the temperature decreases as one goes up the distillation tower. Heavier carbons have higher boiling points. They condense first and are removed in the lower sections of the tower. The lighter hydrocarbons, which have lower boiling points, reach the higher levels of the tower and are file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (3 of 6)19/10/2008 7:26:00 PM

4 separated there. Components separated in the fractional distillation process include: -gasoline used to fuel cars; -naphtha, which is the basis for forming chemicals; - kerosene, which is used for jet fuels; -diesel, a fuel for trucks and cars; -the fuel oil used in boilers and for home heating; -lubricating oil and greases; - asphalts used to surface roads. Internet Link(s) How Oil Refining Works. Read through the process of fractonal distillation and watch the animation of the distillation process. Back To Top Lesson Review In this lesson, you have learned what fossil fuels are, how they are formed, how they are extracted, and some of the ways in which we depend on and use them. In this lesson we completed the following activities: Section 1 - Formation of Fossil Fuels Section 2 - Extraction of Fossil Fuels Back to Top Conclusion In this lesson, you have learned what fossil fuels are, how they are formed, how they are extracted, and some of the ways in which we depend on and use them. In your next lesson, you will examine the combustion reaction and investigate some of the problems that result from the use of fossil fuels. Please check your Science 24 calendar for the date of your upcoming unit test. file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (4 of 6)19/10/2008 7:26:00 PM

5 Back to Top Assignment Please read pages in your text and then complete the following questions. Please answer your questions in a Word document and submit it using the dropbox in D2L. Part A: The Oil Sands Discovery Centre in Fort McMurray, Alberta is located at the world s biggest single oil sand deposit called the Athabasca Oil Sands. As you explore the web site, you will: take a quiz and check your answers; and learn more about the extraction and processing of oil. Internet Link(s) Oil Sands Discovery Centre What to Do: Oil Sands Discovery Centre web site 1. Go to the Oil Sands Discovery Centre web site (above), Top Ten Oil Sands Questions. 2. Read the first multiple choice question and decide on the answer. 3. Follow the instructions to check your answer. If your answer is not correct, try again. Use More Info for additional information. 4. Write a statement that summarizes the answer. (This is what you need to submit to me). 5. Repeat Steps 2 to 4 for the remaining questions. 6. Part B: On the Oil Sands Discovery Centre web site, use the "More Info" icon after the multiple choice questions 5to complete the following: 1. Write a paragraph on each of the following topics: a) how the oil sands are mined b) how the ore is processed Part C: Go to this web site on Drilling Rigs. file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (5 of 6)19/10/2008 7:26:00 PM

6 Internet Link(s) Drilling Rig Web Site Look at the diagram of the drilling rig and what the role is of the different parts. Use this information to complete the assignment below. Word Document Parts of a Drilling Rig diagram and Parts of a Drilling Rig Crossword Puzzle Print these documents and complete them. Look at the diagram of the drilling rig and what the role is of the different parts. Use the drilling rig web site to help you label the parts of the drilling rig provided. Next, use the web site to help you complete the crossword puzzle. Submit your across and down answers to the crossword puzzle. Part D: Turn to page 143 in your text and answer questions 1-3, 5. Total Marks = 27.5 Please make sure you have handed in the following: Attach your completed assignment to the dropbox in D2L and submit it to your teacher. Back to Top Rocky View Virtual School - Revised September 7, 2006 file:///c /Documents%20and%20Settings/Student/My%20Documents/Teacher/SCI24D2L/LPConnect/SCI24U2L72006.htm (6 of 6)19/10/2008 7:26:00 PM