Most people know propane as the fuel in a white container attached to a barbecue grill. http://en.wikipedia.org/wiki/Propane
However, propane can be used for heating homes, heating water, cooking, drying clothes, fueling gas fireplaces, and as an alternative fuel for vehicles. In addition, propane is used to make petrochemicals which are the building blocks for plastics, alcohols, fibers, and cosmetics. Propane can even be used for transportation.
Production: Propane occurs naturally as a gas at atmospheric pressure but turns into liquid if the pressure is moderately increased. It is stored and transported in its compressed liquid form, but by opening a valve to release propane from a pressurized storage container, it is vaporized into a gas for use. Therefore, propane is always a liquid until it is used. Although propane is non-toxic and odorless, an identifying odor is added so the gas can be readily detected.
Propane is not produced for its own sake; it is a by-product of two other processes: natural gas processing and petroleum refining. The diagram below illustrates where propane comes from and how it gets to the consumer.
Natural gas plant production of propane primarily involves extracting materials, such as propane and butane, from natural gas to prevent these liquids from condensing and causing operational problems in natural gas pipelines.
Similarly, when oil refineries make major products, such as motor gasoline and heating oil, some propane is produced as a by-product of those processes. It is important to understand that the by-product nature of propane production means that the volume made available from natural gas processing and oil refining cannot be adjusted when prices and/or demand for propane fluctuate.
In addition to these two processes, demand is met by using imports of propane and by using stored inventories. Although imports provide the smallest, about 10 percent, component of U.S. propane supply, they are vital when consumption exceeds available domestic supplies of propane. Propane is imported by land (via pipeline and rail car from Canada) and by sea (in tankers from such countries as Algeria, Saudi Arabia, Venezuela, Norway, and the United Kingdom).
Usage In Transportation:Transportation represents the smallest sector to use propane. However it is the largest alternative fuel in use today for transportation. When propane is used to fuel internal combustion engines, it is often referred to as autogas. About 9 million vehicles worldwide use autogas. In some countries, it has been used since the 1940s as an alternative fuel for spark ignition engines. More recently, it has also been used in diesel engines. In the U.S., 190,000 on-road vehicles use propane, and 450,000 forklifts use it for power. It is the third most popular vehicle fuel in America, behind gasoline and diesel. Public filling stations are extremely rare. Propane-fueled vehicles are often in commercially-owned fleets, and have private fueling facilities.
Effects In Transportation: Propane is that it is at a liquid state at room temperature. This allows for fast refill times, affordable fuel tank construction, and ranges comparable to, yet still less than gasoline. It is noticeably cleaner and is referred to as the “green gas” because it has less exhaust emissions. It results in less engine wear since there are fewer carbon deposits. Until recently it was less expensive in the United States.
Production: Once a well has been drilled, and the presence of commercially feasible quantities of petroleum has been confirmed, the next step is lifting the natural gas or oil out of the ground and processing it for transportation. Natural gas processing consists of separating all of the various hydrocarbons and fluids from the pure natural gas, to produce what is known as “pipeline quality” dry natural gas. The major transportation pipelines usually require restrictions on the make-up of the natural gas that is allowed into the pipeline. This means that before the natural gas can be transported it has to be purified. Once a natural gas or oil well is drilled, and it has been verified that commercially possible quantities of natural gas are present for extraction, the well must be what is called “completed” to allow for the flow of petroleum or natural gas out of the formation and up to the surface. This process includes strengthening the well hole with casing, evaluating the pressure and temperature of the formation, and then installing the proper equipment to ensure an efficient flow of natural gas out of the well.
Usage: Cars and trucks can use natural gas as a transportation fuel, but they must carry special cylinder-like tanks to hold the fuel. When natural gas is burned to make heat or burned in a car's engine, it burns very cleanly. When you combine natural gas with oxygen, you produce carbon dioxide and water vapor plus the energy that's released in heat and light. Compressed natural gas, which is methane, is used as a clean alternative to other automobile fuels such as gasoline and diesel. The energy efficiency is generally equal to that of gasoline engines, but lower compared with modern diesel engines, partially due to the fact that natural gas engines function using the Otto cycle.
Global Natural Gas Reserves by Country
http://www.irmep.org/datafile.htm
Effects: Some impurities are contained in all natural gas. These include sulfur and butane and other chemicals. When burned, those impurities can create air pollution. The amount of pollution from natural gas is less than burning a more "complex" fuel like gasoline. Natural gas-powered cars are more than 90 percent cleaner than a gasoline-powered car. That's why many people feel natural gas would be a good fuel for cars because it burns cleanly. Natural gas can also be hazardous to life and property through an explosion. Natural gas is lighter than air, and tends to dissipate into the atmosphere. But when natural gas is confined, such as within a house, gas concentrations can reach explosive mixtures and, if ignited, result in blasts that could destroy buildings. However, explosive concerns with compressed natural gas used in vehicles are almost non-existent, due to the escaping nature of the gas, and the need to maintain concentrations between 5% and 15% to trigger explosions.
Definition: Naturally occurring liquid containing a complex mixture of hydrocarbons (molecules made of C and H atoms). Also contains few compounds containing N, S, and O atoms.
Production: Organic matter buried under clay and sand decays by heat, pressure, and time (a million years). Breaking down large molecules of fats, oils, and waxes that contributed to the formation of kerogen produced petroleum.
Primary Recovery
Flush Production—requires no work.
Settled Production—has to be pumped.
Not all oil in a reservoir is recovered.
Enhanced Recovery
Secondary Recovery
Water is pumped to force the oil out.
10-20% of reservoir’s capacity.
Expensive
Tertiary Recovery
Steam, Chemicals, or Bugs are used to reduce crude oil’s viscosity and pump it out.
The world's top five crude oil-producing countries are:
Saudi Arabia
Russia
United States
Iran
China
The United States’ top crude oil-producing states are:
Texas
Alaska
California
Louisiana
New Mexico
Crude Oil in the United States
58% is imported.
25% is produced offshore in the Gulf of Mexico.
(From Class Notes.)
Petroleum is measured in barrels
42 gallons in a barrel.
Abbreviated as “bbls”.
When refined it produces over 44 gallons of petroleum products.
Refinery
Separate different components of crude oil.
Make new materials and fuels by chemical processing.
Make products environmentally acceptable.
Refinery Processes
Distillation - Separation of materials based on differences in their volatility.
Cracking - Breaking of heavy molecules into lighter hydrocarbons.
Reforming - Changing the chemical nature of various hydrocarbons to give desired physical properties.
(From Class Notes.)
The distillation tower separates crude oil into many different fractions according to their boiling points.
Effects:
One of the effects that the energy source of petroleum has on the environment is that related to air and water pollution. The drilling of oil disturbs wildlife on the land and marine life in our oceans. Thanks to new technology, the amount of drilling required to find and recover oil has been decreased by 25% since 1990.
There are various ways in which petroleum cause water pollution. Many people believe that oil spills is the leading cause of oil that is found in the ocean. Even though oil spills are extremely dangerous to wildlife because so much oil is released at once, it only accounts for 2% of the oil that is found in the ocean. Since 1990, oil rigs are required to have “double hulls,” which is an extra lining to help prevent oil spills. More common methods that oil gets into the ocean are from the natural seeps in the ocean floor. Also, oil that drips from motor products on land, such as gasoline spilled from lawnmowers, is carried by rainwater to streams and rivers and eventually to the oceans, polluting it. Water also leaks into the ocean from various motorboats.
The burning of petroleum pollutes the air due to the release of carbon dioxide. The release of this greenhouse gas is what is causing global warming. Petroleum usage also gives off carbon monoxide, nitrogen oxide and sulfur. New regulations that are currently being put into affect will vastly decrease the amount of sulfur admissions in the atmosphere.
"Energy Kids Page." Energy Information Administration. 2006. U.S. Department of Energy. 26 Nov. 2006
http://www.eia.doe.gov/kids/energyfacts/uses/consumption.html
