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U.S. Oil and Gas Pipelines

The first oil pipeline in the United States was built in 1865, following the discovery of oil in Pennsylvania. By the early 1900s, major discoveries had been made in Texas, Oklahoma and Kansas and pipelines had become a common method of moving crude oil. However, these early pipelines have long since been decommissioned. They were small diameter pipes that were quite inefficient by today's standards.

Leading up to World War II, pipeline companies were operating a maze of these small-diameter pipes laid out in parallel in order to carry enough capacity to fulfill the nation's needs for petroleum. Pump stations were powered by diesel engines, and were usually spaced every 30 miles. Each of these pump stations had to be manned around the clock to keep the system operating properly and the coordination of these multiple operating stations meant there was a lot more opportunity for human error.

Following the war, a technological revolution took place. The need for technological improvements in oil pipelines was driven by three factors.
•Consumer demand for petroleum in the prosperity of the Fifties.
•The growth of American industry that took place during the war.
•Increasing awareness of the importance of petroleum to the nation's security interests following wartime gasoline rationing. (More than 100 military bases and other facilities have their own direct connections with oil pipelines.)

Pipelines move nearly two-thirds of the oil and petrleum products transported annually. Pipelines are, by far, America's most important petroleum supply line, including crude oil, refined fuel and raw materials.

Interstate pipelines deliver over 11.3 billion barrels of petroleum each year. (There are 42 gallons in a barrel.) About 52% of the petroleum transported by pipelines is crude oil and 47% is in the form of refined petroleum products. The cost to transport a barrel of petroleum products from Houston to the New York harbor is about $1, or about 2 1/2 ¢ per gallon at your local gasoline station. The price to transport petroleum products through pipelines does not change, regardless of fluctuations in the price of a gallon of gas. Tell me more about the economic regulation of pipelines

The network of crude oil pipelines in the U.S. is extensive. There are approximately 55,000 miles of crude oil trunk lines (usually 8 - 24 inches in diameter) in the U.S. that connect regional markets.

The U.S. also has an estimated 30,000 to 40,000 miles of small gathering lines (usually 2 to 6 inches in diameter) located primarily in Texas, Oklahoma, Louisiana, and Wyoming with small systems in a number of other oil producing states. These small lines gather the oil from many wells, both onshore and offshore, and connect to larger trunk lines measuring from 8 to 24 inches in diameter.

Crude oil is also subdivided in to 'Gathering Lines' and 'Trunk Lines.'

First, gathering lines are very small pipelines usually from 2 to 8 inches in diameter in the areas of the country in which crude oil is found deep within the earth. It is estimated that there are between 30,000 to 40,000 miles of these small gathering lines located primarily in Texas, Oklahoma, Louisiana, and Wyoming with small systems in a number of other oil producing states. These small lines gather the oil from many wells, both onshore and offshore, and connect to larger trunk lines measuring from 8 to 24 inches in diameter.

Trunk lines include a few very large lines, such as the Trans Alaska Pipeline System, which is 48 inches in diameter. The larger cross-country crude oil transmission pipelines bring crude oil from producing areas to refineries. There are approximately 55,000 miles of crude oil trunk lines in the U.S.

The next group of oil pipelines are those carrying refined petroleum products – gasoline, jet fuel, home heating oil and diesel fuel.

These refined product pipelines vary in size from relatively small 8 to 12 inch diameter lines up to 42 inches in diameter. Refined products pipelines are found in almost every state in the U.S, with the exception of some New England states. The total mileage nationwide of refined products pipelines is approximately 95,000 miles. These pipelines deliver petroleum products to large fuel terminals with storage tanks to be loaded into tanker trucks. Trucks cover the last few miles to make local deliveries to gas stations and homes. Major industries, airports and electrical power generation plants are supplied directly by pipeline.

 

U.S. Natural Gas Pipeline Network

The U.S. natural gas pipeline network is a highly integrated transmission and distribution grid that can transport natural gas to and from nearly any location in the lower 48 States. The natural gas pipeline grid comprises:
  • More than 210 natural gas pipeline systems.
  • 305,000 miles of interstate and intrastate transmission pipelines .
  • More than 1,400 compressor stations that maintain pressure on the natural gas pipeline network and assure continuous forward movement of supplies .
  • More than 11,000 delivery points, 5,000 receipt points, and 1,400 interconnection points that provide for the transfer of natural gas throughout the United States.
  • 24 hubs or market centers that provide additional interconnections .
  • 400 underground natural gas storage facilities .
  • 49 locations where natural gas can be imported/exported via pipelines .
  • 8 LNG (liquefied natural gas) import facilities and 100 LNG peaking facilities 

Transporting natural gas from the wellhead to the final customer involves several physical transfers of custody and multiple processing steps. A natural gas pipeline system begins at the natural gas producing well or field. Once the gas leaves the producing well, a pipeline gathering system directs the flow either to a natural gas processing plant or directly to the mainline transmission grid, depending upon the initial quality of the wellhead product.

The processing plant produces pipeline-quality natural gas. This gas is then transported by pipeline to consumers or is put into underground storage for future use. Storage helps to maintain pipeline system operational integrity and/or to meet customer requirements during peak-usage periods.

Transporting natural gas from wellhead to market involves a series of processes and an array of physical facilities. Among these are:

  • Gathering Lines – These small-diameter pipelines move natural gas from the wellhead to the natural gas processing plant or to an interconnection with a larger mainline pipeline.
  • Processing Plant – This operation extracts natural gas liquids and impurities from the natural gas stream.
  • Mainline Ttransmission Systems – These wide-diameter, long-distance pipelines transport natural gas from the producing area to market areas.
  • Market Hubs/Centers – Locations where pipelines intersect and flows are transferred.
  • Underground Storage Facilities – Natural gas is stored in depleted oil and gas reservoirs, aquifers, and salt caverns for future use.
  • Peak Shaving – System design methodology permitting a natural gas pipeline to meet short-term surges in customer demands with minimal infrastructure. Peaks can be handled by using gas from storage or by short-term line-packing.

The Natural Gas Gathering System

A natural gas pipeline system begins at a natural gas producing well or field. In the producing area many of the pipeline systems are primarily involved in "gathering" operations. That is, a pipeline is connected to a producing well, converging with pipes from other wells where the natural gas stream may be subjected to an extraction process to remove water and other impurities if needed. Natural gas exiting the production field is usually referred to as "wet" natural gas if it still contain significant amounts of hydrocarbon liquids and contaminants.

Under certain conditions some or all of the natural gas produced at a well may be returned to the reservoir in cycling, repressuring, or conservation operations and/or vented and flared. At this stage it is a mixture of methane and other hydrocarbons, as well as some non-hydrocarbons, existing in the gaseous phase or in a solution with crude oil. The principal hydrocarbons normally contained in the natural gas mixture are methane, ethane, propane, butane, and pentane. Typical non-hydrocarbon gases that may be present in reservoir natural gas are water vapor, carbon dioxide, helium, hydrogen sulfide, and nitrogen.

Credit:BP, Energy Information Administration, U.S. Department of Energy, CIA, American Gas Association,Association of Oil Pipe Lines