STEM Curriculum & Labs
1. FORMATION
Are fossil fuels renewable or non-renewable? Experiments show how the earth “cooked” (heat and pressure) ancient plant and animal life to create fossil fuels. Create infographics about geologic time and the rock cycle.
2. MIGRATION AND TRAPPING
Are crude oil and natural gas found in large lakes underneath the earth’s surface? Experiments show how crude oil and natural gas are trapped in porous rocks. Create 2D and 3D rock models to demonstrate porosity and permeability.
3. EXPLORATION
How do we find these valuable fossil fuels? Use contour mapping to look below the earth’s surface and “see” rock formations. Create models and calibrate measurements using blank grids.
4. DRILLING AND WELL STIMULATION
How do we recover crude oil and natural gas? Use engineering design to create two models: a weight-bearing derrick and a working oil well, applying principles related to porosity, permeability, and flow of fluids to the surface.
5. PRODUCING AND TRANSPORTING
What happens to crude oil and natural gas once it is produced? How is it transported? Create a model pipeline and pipeline “pig” and apply principles of force, motion, velocity, and engineering design.
6. REFINING AND PROCESSING
How are crude oil and natural gas liquids (NGLs) transformed into useful products? Use the chemistry distillation procedure to demonstrate the refining process. Follow lab safety procedures, collect data, and understand the industry applications.
7. PETROCHEMICALS AND PRODUCTS
What other products besides transportation fuels are made from crude oil and natural gas? Explore a few of the 6,000 petroleum-based products. Design and implement a materials test for different petrochemical-based fabrics.
1. FORMATION
How did crude oil and natural gas form? What forces of nature created reservoir and source rocks?
BACKGROUND
Crude oil and natural gas are called fossil fuels because they were created from biotic materials: tiny terrestrial marine plants and animals. Millions of years ago, these microscopic plants and animals absorbed energy from the sun, which was stored as carbon molecules in their bodies. They died and were buried by layers of sediment, water and sand. Microscopic organisms fed on the decomposing organic material in a process called biogenesis. Specific high temperatures and pressure conditions are required to induce formation of hydrocarbons, such as crude oil, wet gas, dry gas, etc.
Geologic time and the rock cycle play an important role in the formation of these hydrocarbons.
There are two types of rocks that are important in crude oil and natural gas formation: reservoir rocks and source rocks. Reservoir rocks are where the hydrocarbons migrate (from historic production) and become trapped. Most source rocks are gray or black shale. Biotic materials that form hydrocarbons are incorporated into source rocks when they are formed.
1.2 Biotic Materials
1.3 Listen & Draw Geologic Time
When were crude oil and natural gas formed?
ASSESSMENT
1.4 Geologic Puzzle
DIGITAL EXTRAS
2. MIGRATION AND TRAPPING
Are there lakes of crude oil and natural gas underground? Where is it stored?
BACKGROUND
Porosity and permeability are two of the primary factors that control the movement and storage of fluids in rocks and sediments. Porosity is the ratio of the volume of openings (voids) to the total volume of material. Porosity represents the storage capacity of the geologic material. Porous rocks, such as sandstone and limestone, contain tiny spaces, called pores, that can hold natural gas, water and crude oil, like a sponge. Non-porous rocks, such as granite, do not have pore spaces. After crude oil and natural gas are formed, they tend to migrate upward through the rock layers due to pressure within the earth. Both liquids and gases move based on their properties and the natural flow of fluids from areas of higher to lower pressure.
The ability of liquids and gases to move through these spaces is called permeability. The permeability of a rock is a measure of the resistance to the flow of a fluid or gases through a rock. If it takes a lot of pressure to squeeze fluid through a rock, that rock has low permeability. If fluid passes through the rock easily, it has high permeability. Recently, an increasing amount of U.S. gas production is coming from shale. Shale, a source rock, is generally more porous, but has extremely low permeability and traditionally it had been a poor producer of hydrocarbons. Evolving well stimulation techniques have rendered low-permeability shale reservoirs more permeable
2.2 Porosity & Permeability
ASSESSMENT
2.3 Create Rock Models
How can you show porosity and permeability in a 2D or 3D model?
DIGITAL EXTRAS
Oil on My Shoes: Porosity and Permeability
Rock Porosity video by SPEBUE IVL
3. EXPLORATION
How do you know where crude oil and natural gas can be found?
BACKGROUND
One of the tools geoscientists use in order to find crude oil and natural gas beneath the surface is seismic technology. Other tools include underground mapping and core sampling. “Topographic maps” of formations underground, such as isopach maps and structure maps, can help geologists find the formations that may be reservoirs for crude oil. These maps, constructed using well log data, show the thickness of sediments below the surface and can be useful in crude oil and natural gas well placement.
Many types of well logs are used to measure the radioactivity, permeability, electrical conductivity, porosity, or some combination of factors. Advances in technology have made geologists’ efforts to find crude oil and natural gas more precise and effective.
Seismic imaging is a tool that bounces sound waves off underground rock structures to reveal possible crude oil and natural gas–bearing rock formations. Seismologists use ultra-sensitive devices called geophones to record the sound waves as they echo within the earth. By studying the echoes, petroleum geologists seek to calculate the depth and structures of rock formations.
Sophisticated 3D imaging creates high-definition pictures similar to an X-ray scan or medical sonogram, that covers several square miles and extends miles into the earth. Geophysicists analyze these images and predict whether the structures revealed are conducive to containing reservoirs of crude oil and natural gas. The only way to confirm the prediction is by actually drilling wells.
Recording multiple 3D surveys at different times produces 4D information.
The images show a reservoir at different stages of depletion, allowing petroleum engineers to improve recovery and produce the resource more efficiently and effectively.
3.2 Skewer Contour Mapping
ASSESSMENT
3.3 Seismic Assessment
How does the industry use sound waves?
DIGITAL EXTRAS
Contour Mapping Activity
Isopach Map Examples
Using Hamm Seismograph in Classroom
4. DRILLING AND WELL STIMULATION
How do you get crude oil and natural gas out of the ground?
BACKGROUND
Once geoscientists find potentially productive rock formations, potential risks are assessed and data is compiled regarding the drilling site. Drilling may be one of three types: vertical, directional or horizontal; many wells may also have a combination of these. Vertical drilling goes down to the depth where the crude oil and/or natural gas formation is believed to be. Directional drilling allows deposits to be reached without disturbing the land directly above the deposit. Horizontal drilling is a technique where the drilling can take a gradual 90-degree turn from the vertical and extend horizontally through a formation for a mile or more.
A derrick typically stands more than 100 feet in height and uses a drill string (many joints of steel alloy drill pipe with drill collars) and the drill bit, which is capable of drilling through the earth. It is cooled with a constant slurry of mud to prevent it from getting too hot and to help bring rock cuttings back to the surface. A drill bit grinds into the rock layers creating rice-sized particles. The entire drill string is rotated at the surface.
Protecting the aquifer is a major priority, so casing made of steel is lowered into the hole and cemented into place. At a pre-set depth, drillers are required to place additional cement and casing to add extra protection.
For horizontal wells, downhole instruments that transmit various sensor readings to operators at the surface are included in the drill string near the bit. Modern downhole instrumentation allows the drilling crew to calculate the position (x, y, and z coordinates) of the drill bit at all times. Horizontal drilling is expensive, and can cost up to three times as much per foot as drilling a vertical well. The extra cost is usually recovered by increased production from the well. Many profitable wells would be failures without these methods.
After the well is completed, it is necessary to stimulate the flow of crude oil and natural gas into the well. Hydraulic fracturing is used to enhance the permeability and allow more flow of crude oil and natural gas into the well. This is not a new technology; it has been around since the 1940’s. However, recent advances allow crude oil and natural gas operators to render low-permeability shale reservoirs more permeable by injecting fracturing fluids, consisting primarily of water and sand, under high pressure into the formation. This creates tiny fissures that allow for fluid and gases to flow to the well bore.
4.2 Build a Model Oil Well
How can crude oil be most efficiently removed from a model oil well?
ASSESSMENT
Use a Venn Diagram to compare and contrast vertical, directional and horizontal drilling. Ideas to include: depth of wells, protection of the aquifer, environmental impacts, possible production, and number of well holes needed.
DIGITAL EXTRAS
Fracturing fluids in Ohio
Horizontal, Vertical and Directional Drilling
A Crude Story – Horizontal Drilling
American Petroleum Institute – Story of Oil and Natural Gas
5. PRODUCING AND TRANSPORTING
What happens to crude oil and natural gas once it is produced? How is it transported?
BACKGROUND
Once the drilling is complete, specialized equipment manages the extraction of hydrocarbons. A wellhead at the surface of the well can withstand upward pressure of escaping gases and fluids. Natural gas, the least dense material, will often naturally rise to the surface. A “christmas tree,” a series of pipes and tubes about 6 feet high, can be installed to regulate the flow of hydrocarbons. Some crude oil and natural gas must be lifted by a special pump, called a pump jack. The crude oil, natural gas and sometimes brine (or saltwater) is then separated for further processing. A conventional separator is where the force of gravity serves to separate the heavier liquids like oil, from the lighter gases, like natural gas, which is shipped out through an elaborate series of pipelines to processing plants or storage facilities.
The natural gas enters a compressor station before entering a pipeline, where it travels at pressures anywhere from 200-1,500 pounds per square inch (psi). Compressor stations are placed at 40-100 mile intervals along a pipeline in order to increase the volume of natural gas being transported (up to 600 times) and maintain appropriate pressurization. Interstate pipelines are typically 24–36 inches in diameter and all pipelines are made of steel or plastic with corrosive protection and maintenance records are kept on all repairs.
Pigging describes various processes that allow for inspection and maintenance of a pipeline from within the pipeline itself. If maintenance is needed, specialized pigs can be used to remove debris, paraffin build-up or give a video inspection within the pipe. “Smart pigs” have become increasingly sophisticated, targeting specific types of pipeline issues that may restrict the flow of materials through the line.
Constructing pipelines takes a great deal of planning and preparation including feasibility studies to ensure that a route provides the least impact to the environment and public infrastructure already in place. In addition, safety precautions may include aerial patrols, leak detection devices, pipeline markers, and earthquake-proof braces that allow for minor shifts in the earth.
ACTIVITIES
5.1 Transporting Natural Gas
5.2 Pipeline Pigging
ASSESSMENT
After reviewing the production and transport of crude oil and natural gas, what issues need to be addressed to efficiently get the energy to the end-user?
What are some ways these issues can be addressed?
DIGITAL EXTRAS
6. REFINING AND PROCESSING
How are crude oil and natural gas liquids transformed into useful products?
BACKGROUND
The crude oil and wet gas (natural gas saturated with more complex hydrocarbons) pumped from underground reservoirs are energy-rich, organic concentrates: mixtures of hundreds of molecular compounds with tremendous potential. At the refinery, the strategy for separating these compounds is based on the different properties of the components. Nothing is wasted, and the byproducts from one process are often integral to another. For example, from wet gas, we get ethane, which is used to create ethylene, a component of many consumer plastics. Different hydrocarbons can be separated by their boiling points. The smallest hydrocarbon is methane (natural gas), and the longest chains are like wax or tar. The more carbons in a molecule, the higher the boiling point. This is done through fractional distillation. The steps of fractional distillation mirror those of distillation in a chemistry lab.
heat with high-pressure steam to about 1112 °F.
boiling creates gases and vapors that rise in a column.
as the vapor goes through the column it cools and condenses where the temperature of the column is equal to that of the substance’s boiling point (substance with the lowest boiling point will condense at the highest point in the column).
various liquid fractions are collected.
liquid fractions pass into condensers for further cooling and are transported for further chemical processing and blended to produce a variety of petrochemical products.
Refineries use chemical reactions on some of the fractions (a process called conversion) to create many products. Cracking is used to break large hydrocarbons into smaller ones. Reforming takes smaller hydrocarbons and combines them to make larger ones. During alkylation, the molecules of one fraction are rearranged to produce another. The distilled and chemically treated fractions are treated to remove impurities, cooled, and blended to make gasoline, lubricating oils, jet fuel, heating oil, and chemicals of various grades for making plastics and other polymers.
6.2 Refinery Card Sort
ASSESSMENT
Create hydrocarbon models using ball and stick models. Examples: propane, butane, isobutane, benzene, ethylene.
DIGITAL EXTRAS
7. PETROCHEMICALS AND PRODUCTS
What other products besides transportation fuels are made from crude oil and natural gas? How do these products impact your everyday life?
BACKGROUND
Crude oil is a mix of hydrocarbons that can be processed to give us petrochemicals including synthetic alternatives to natural materials (rubber) and unique materials such as nylon. Petrochemistry is a fairly young industry; it only started to grow in the 1940s, more than 80 years after the drilling of the first commercial oil well in 1859. During World War II, the demand for synthetic materials to replace costly and sometimes less efficient products caused the petrochemical industry to grow.
Petrochemistry gets its feedstock (raw material) from the refinery: naphtha, components of natural gas such as butane, and some of the by-products of oil refining processes, such as ethane and propane. These feedstocks are then processed through an operation that is known as cracking. Cracking is simply the process of breaking down heavy hydrocarbon molecules into lighter, more valuable fractions. In steam cracking, high temperatures are used; when a catalyst is used it is known as catalytic cracking.
Once these operations are concluded, new products are obtained, the building blocks of the petrochemical industry: such as olefins (ethylene, propylene) and aromatics (benzene, toluene, and the xylenes). These products are processed in petrochemical plants into other, more specialized products to be used by the so-called downstream industries, the customer industries of petrochemistry.
ethylene – trash bags, packaging
propylene – packaging, plastic lids
benzene – solvents, resins, nylon
toluene – high-octane fuel, polyurethane
xylenes – polyester fabric
In the end, petrochemicals will go into products that we are all familiar with: plastics, soaps and detergents, healthcare products such as aspirin, synthetic fibers for clothes and furniture, rubber, and paints.
7.2 Materials & Their Properties
ASSESSMENT
Describe a day without oil.
DIGITAL EXTRAS
Products poster
Polymers from petroleum
A guide to common plastics