Onyx Power and Gas Consulting continues a weekly series of an overall view of energy, starting from the basics of what energy is to a detailed analysis of energy on a global scale including renewable energy sources. This series of news articles should provide a complete course on energy…enjoy, check out archives and come back each week for additional information on how all sorts of energy sources impact our daily lives.
Propane from Natural Gas or Oil
Propane is an energy-rich gas, C3H8. It is one of the liquefied petroleum gases (LP-gases or LPGs) that are found mixed with natural gas and oil. Propane and other liquefied gases, including ethane and butane, are separated from natural gas at natural gas processing plants, or from crude oil at refineries. The amount of propane produced from natural gas and from oil is roughly equal.
Propane naturally occurs as a gas. However, at higher pressure or lower temperatures, it becomes a liquid. Because propane is 270 times more compact as a liquid than as a gas, it is transported and stored in its liquid state. Propane becomes a gas again when a valve is opened to release it from its pressurized container. When returned to normal pressure, propane becomes a gas so that we can use it.
Liquefied Petroleum Gases Were Discovered in 1912
Liquefied petroleum gases are mixtures of propane, ethane, butane, and other gases that are produced at natural gas processing plants and refineries. Fractionation plants then separate the liquids from each other.
LP-gases were discovered in 1912 when a U.S. scientist, Dr. Walter Snelling, discovered that these gases could be changed into liquids and stored under moderate pressure. The LP-gas industry got its start shortly before World War I when a problem in the natural gas distribution process occurred. A section of the pipeline in one natural gas field ran under a cold stream, and the coldness led to a lot of liquids building up in the pipeline, sometimes to the point of blocking the entire pipeline. Soon, engineers figured out a solution: facilities were built to cool and compress natural gas, and to separate the gases that could be turned into liquids (including propane and butane).
Getting Propane to Consumers
How does propane get to the people who use it? Propane usually goes by underground pipeline to terminals across the country. Railroads, barges, trucks, and supertankers also ship propane to bulk distributors.
Local propane dealers come to the distributor’s bulk plant to fill up their small tank trucks. These tank trucks, called “bobtails,” deliver propane to large storage tanks that are outside homes. The average residential propane tank holds between 500 and 1,000 gallons of liquid fuel, and is refilled several times a year. People who use just a little propane, for a backyard barbecue, for example, bring their tanks to convenience and hardware stores to be filled or to be exchanged for full ones.
How Crucial Winter Inventories Are Stored and Delivered
There are three types of storage for propane inventories (stocks) — primary, secondary, and tertiary:
- Primary storage consists of refinery, gas plant, pipeline, and bulk terminal stocks. Primary inventory withdrawals provide the second largest source of propane during the winter heating season, the largest source being production from natural gas plants and refineries. Propane storage facilities at the primary level are generally located near the major production and transportation hubs and consist of pressurized depleted mines and underground salt dome storage caverns clustered mostly in Conway, Kansas, and Mont Belvieu, Texas. The reservoirs are linked directly to the major natural gas liquids pipelines and are capable of maintaining high deliverability rates during peak demand periods.
- Secondary storage consists primarily of large, pressurized above-ground tanks located at approximately 25,000 retail dealers scattered throughout the United States.
- Tertiary storage consists of small above-ground tanks located mostly at residences and commercial establishments.
Propane Is Largely Transported by Pipeline
The primary mode of transporting propane within the United States is by approximately 70,000 miles of interstate pipelines. The pipeline system is most developed along the corridors between production areas and petrochemical consumers along the Gulf Coast and the agricultural-industrial consumers in the Midwest.
The Northeast and South Atlantic States each are served by a single pipeline. The upper Midwest also is served by two lines from Canada.
Other modes of transport include about 22,000 rail tank cars, 6,000 highway bulk transports, 18,000 local delivery trucks, about 60 inland waterway barges, and several ocean-going tankers.
The professional consultants at Onyx Power & Gas Consulting are always ahead of the current issues that may affect energy consumption and pricing. Now is the time to partner with an Onyx professional consultant to discuss energy management and secure energy prices based on today’s stable pricing. Volatility in the energy markets makes it too precarious to take chances. Partner with Onyx Power & Gas in Making Energy Make a Difference!