Pipeline transport

Pipeline transport is the transportation of goods through a pipe. Most commonly, liquids and gases are sent, but pneumatic tubes that transport solid capsules using compressed air are also used.

As for gases and liquids, any chemically stable substance can be sent through a pipeline. Therefore sewage, slurry, water, or even beer pipelines exist; but arguably the most valuable are those transporting fuels: oil (oleoduct), natural gas (gas grid), and biofuels.

Dmitri Mendeleev first suggested using a pipe for transporting petroleum in 1863.

Contents

Types by transported substance

For oil or natural gas

There is some argument as to when the first crude oil pipeline was built. However, some say pipeline transport was pioneered by Vladimir Shukhov and the Branobel company in the late 19th century. Others say oil pipelines originated when the Oil Transport Association first constructed a 2-inch (51 mm) wrought iron pipeline over a 6-mile (9.7 km) track from an oil field in Pennsylvania to a railroad station in Oil Creek, in the 1860s. Pipelines are generally the most economical way to transport large quantities of oil, refined oil products or natural gas over land. Compared to shipping by railroad, they have lower cost per unit and higher capacity. Although pipelines can be built under the sea, that process is economically and technically demanding, so the majority of oil at sea is transported by tanker ships.

The market size for oil and gas pipeline construction experienced tremendous growth prior to the economic downturn in 2008. The industry grew from $23 billion in 2006 to $39 billion in 2008. [2]

Oil pipelines are made from steel or plastic tubes with inner diameter typically from 4 to 48 inches (100 to 1,200 mm). Most pipelines are typically buried at a depth of about 3 to 6 feet (0.91 to 1.8 m). The oil is kept in motion by pump stations along the pipeline, and usually flows at speed of about 1 to 6 metres per second (3.3 to 20 ft/s). Multi-product pipelines are used to transport two or more different products in sequence in the same pipeline. Usually in multi-product pipelines there is no physical separation between the different products. Some mixing of adjacent products occurs, producing interface. At the receiving facilities this interface is usually absorbed in one of the product based on pre-calculated absorption rates.

Crude oil contains varying amounts of wax, or paraffin, and in colder climates wax buildup may occur within a pipeline. Often these pipelines are inspected and cleaned using pipeline inspection gauges, pigs, also known as scrapers or Go-devils. Smart pigs (also known as intelligent or intelligence pigs) are used to detect anomalies in the pipe such as dents, metal loss caused by corrosion, cracking or other mechanical damage.[3] These devices are launched from pig-launcher stations and travel through the pipeline to be received at any other station down-stream, either cleaning wax deposits and material that may have accumulated inside the line or inspecting and recording the condition of the line.

For natural gas, pipelines are constructed of carbon steel and vary in size from 2 to 60 inches (51 to 1,500 mm) in diameter, depending on the type of pipeline. The gas is pressurized by compressor stations and is odourless unless mixed with a mercaptan odorant where required by a regulating authority.

For ammonia

Highly-toxic ammonia is theoretically the most dangerous substance to be transported through long-distance pipelines. However, practically incidents on ammonia-transporting lines are uncommon - unlike on industrial ammonia-processing equipment.

A major example of ammonia pipeline is the Ukrainian Transammiak line connecting the TogliattiAzot facility in Russia to the exporting Black Sea-port of Odessa.

For biofuels (ethanol and biobutanol)

Pipelines have been used for transportation of ethanol in Brazil, and there are several ethanol pipeline projects in Brazil and the United States.[4] Main problems related to the shipment of ethanol by pipeline are its high oxygen content, which makes it corrosive, and absorption of water and impurities in pipelines, which is not a problem with oil and natural gas.[4][5] Insufficient volumes and cost-effectiveness are other considerations limiting construction of ethanol pipelines.[5][6]

For coal and ore

Slurry pipelines are sometimes used to transport coal or ore from mines. The material to be transported is closely mixed with water before being introduced to the pipeline; at the far end, the material must be dried. One example is a 525 km slurry pipeline which is planned to transport iron ore from the Minas-Rio mine (producing 26.5 million tonnes per year) to a port at Açu in Brazil.[7] An existing example is the 85 km Savage River Slurry pipeline in Tasmania, Australia, possibly the world's first when it was built in 1967. It includes a 366m bridge span at 167m above the Savage River.[8][9]

For hydrogen

Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the hydrogen infrastructure. Hydrogen pipeline transport is used to connect the point of hydrogen production or delivery of hydrogen with the point of demand, with transport costs similar to CNG,[10] the technology is proven.[11] Most hydrogen is produced at the place of demand with every 50 to 100 miles (160 km) an industrial production facility.[12] The 1938 - Rhine-Ruhr 240 km hydrogen pipeline is still in operation.[13] As of 2004 there are 900 miles (1,400 km) of low pressure hydrogen pipelines in the USA and 930 miles (1,500 km) in Europe.

For water

Two millennia ago the ancient Romans made use of large aqueducts to transport water from higher elevations by building the aqueducts in graduated segments that allowed gravity to push the water along until it reached its destination. Hundreds of these were built throughout Europe and elsewhere, and along with flour mills were considered the lifeline of the Roman Empire. The ancient Chinese also made use of channels and pipe systems for public works. The famous Han Dynasty court eunuch Zhang Rang (d. 189 AD) once ordered the engineer Bi Lan to construct a series of square-pallet chain pumps outside the capital city of Luoyang.[14] These chain pumps serviced the imperial palaces and living quarters of the capital city as the water lifted by the chain pumps was brought in by a stoneware pipe system.[14][15]

Pipelines are useful for transporting water for drinking or irrigation over long distances when it needs to move over hills, or where canals or channels are poor choices due to considerations of evaporation, pollution, or environmental impact.

The 530 km (330 mi) Goldfields Water Supply Scheme in Western Australia using 750 mm (30 inch) pipe and completed in 1903 was the largest water supply scheme of its time.[16][17]

Examples of significant water pipelines in South Australia are the Morgan-Whyalla (completed 1944) and Mannum-Adelaide [18] (completed 1955) pipelines.

There are two Los Angeles, California aqueducts, the First Los Angeles Aqueduct (completed 1913) and the Second Los Angeles Aqueduct (completed 1970) which also include extensive use of pipelines.

For beverages

For beer

Bars in the Veltins-Arena, a major football ground in Gelsenkirchen, Germany, are interconnected by a 5 km long beer pipeline. It is the favourite method for distributing beer in such large stadiums, because the bars have to overcome big differences between demands during various stages of a match; this allows them to be supplied by a central tank.

In Randers city in Denmark, the so-called Thor beer pipeline still exists. Originally copper pipes were running directly from the brewery, and, when in 90s the brewery moved out the city, Thor beer replaced the centre of a star with a giant tank.

For other uses

The town of Hallstatt in Austria claims to contain "the oldest industrial pipeline in the world", dating back to 1595.[19] It was constructed from 13,000 trunks to transport saline solution for 40 kilometers from Hallstatt to Ebensee.[20]

Types by transport function

In general, pipelines can be classified in three categories depending on purpose:

Gathering pipelines
Group of smaller interconnected pipelines forming complex networks with the purpose of bringing crude oil or natural gas from several nearby wells to a treatment plant or processing facility. In this group, pipelines are usually short- a couple of hundred metres- and with small diameters. Also sub-sea pipelines for collecting product from deep water production platforms are considered gathering systems.
Transportation pipelines
Mainly long pipes with large diameters, moving products (oil, gas, refined products) between cities, countries and even continents. These transportation networks include several compressor stations in gas lines or pump stations for crude and multiproducts pipelines.
Distribution pipelines
Composed of several interconnected pipelines with small diameters, used to take the products to the final consumer. Feeder lines to distribute gas to homes and businesses downstream. Pipelines at terminals for distributing products to tanks and storage facilities are included in this group.

Construction

When a pipeline is built, the construction project not only covers the civil work to lay the pipeline and build the pump/compressor stations, it also has to cover all the work related to the installation of the field devices that will support remote operation.

The pipeline is routed along what is known as a 'right of way'. Pipelines are generally built using the following stages:

1. Route (right of way) Selection
2. Surveying the route
3. Clearing the route
4. Trenching - Main Route and Crossings (roads, rail, other pipes, etc)
5. Installing the pipe
6. Installing valves, intersections, etc.
7. Covering the pipe and trench

Operation

Field devices are instrumentation, data gathering units and communication systems. The field Instrumentation includes flow, pressure and temperature gauges/transmitters, and other devices to measure the relevant data required. These instruments are installed along the pipeline on some specific locations, such as injection or delivery stations, pump stations (liquid pipelines) or compressor stations (gas pipelines), and block valve stations.

The information measured by these field instruments is then gathered in local Remote Terminal Units (RTU) that transfer the field data to a central location in real time using communication systems, such as satellite channels, microwave links, or cellular phone connections.

Pipelines are controlled and operated remotely, from what is usually known as The Main Control Room. In this center, all the data related to field measurement is consolidated in one central database. The data is received from multiple RTUs along the pipeline. It is common to find RTUs installed at every station along the pipeline.

The SCADA system at the Main Control Room receives all the field data and presents it to the pipeline operator through a set of screens or Human Machine Interface, showing the operational conditions of the pipeline. The operator can monitor the hydraulic conditions of the line, as well as send operational commands (open/close valves, turn on/off compressors or pumps, change setpoints, etc.) through the SCADA system to the field.

To optimize and secure the operation of these assets, some pipeline companies are using what is called Advanced Pipeline Applications, which are software tools installed on top of the SCADA system, that provide extended functionality to perform leak detection, leak location, batch tracking (liquid lines), pig tracking, composition tracking, predictive modeling, look ahead modeling, operator training and more.

Technology

Components

Pipeline networks are composed of several pieces of equipment that operate together to move products from location to location. The main elements of a pipeline system are:

Initial injection station
Known also as supply or inlet station, is the beginning of the system, where the product is injected into the line. Storage facilities, pumps or compressors are usually located at these locations.
Compressor/pump stations
Pumps for liquid pipelines and Compressors for gas pipelines, are located along the line to move the product through the pipeline. The location of these stations is defined by the topography of the terrain, the type of product being transported, or operational conditions of the network.
Partial delivery station
Known also as intermediate stations, these facilities allow the pipeline operator to deliver part of the product being transported.
Block valve station
These are the first line of protection for pipelines. With these valves the operator can isolate any segment of the line for maintenance work or isolate a rupture or leak. Block valve stations are usually located every 20 to 30 miles (48 km), depending on the type of pipeline. Even though it is not a design rule, it is a very usual practice in liquid pipelines. The location of these stations depends exclusively on the nature of the product being transported, the trajectory of the pipeline and/or the operational conditions of the line.
Regulator station
This is a special type of valve station, where the operator can release some of the pressure from the line. Regulators are usually located at the downhill side of a peak.
Final delivery station
Known also as outlet stations or terminals, this is where the product will be distributed to the consumer. It could be a tank terminal for liquid pipelines or a connection to a distribution network for gas pipelines.

Leak detection systems

Since oil and gas pipelines are an important asset of the economic development of almost any country, it has been required either by government regulations or internal policies to ensure the safety of the assets, and the population and environment where these pipelines run.

Pipeline companies face government regulation, environmental constraints and social situations. Pipeline companies should comply with government regulations which may define minimum staff to run the operation, operator training requirements, up to specifics including pipeline facilities, technology and applications required to ensure operational safety. As an example, in the State of Washington, it is mandatory for pipeline operators to be able to detect and locate leaks of 8 percent of maximum flow within 15 minutes or less.

The social situation also affects the operation of pipelines. In third world countries, product theft is a problem for pipeline companies. It is common to find unauthorized extractions in the middle of the pipeline. In this case, the detection levels should be under 2 percent of maximum flow, with a high expectation for location accuracy.

Different types of technologies and strategies have been implemented, from physically walking the lines to satellite surveillance. The most common technology to protect these lines from occasional leaks is known as Computational Pipeline Monitoring Systems or CPM. CPM takes information from the field related to pressures, flows, and temperatures to estimate the hydraulic behavior of the product being transported. Once the estimation is done, the results are compared to other field references to detect the presence of an anomaly or unexpected situation, which may be related to a leak.

The American Petroleum Institute has published several articles related to the performance of CPM in liquids pipelines, the API Publications are:

Implementation

As a rule pipelines for all uses are laid in most cases underground. However in some cases it is necessary to cross a valley or a river on a pipeline bridge. Pipelines for centralized heating systems are often laid on the ground or overhead. Pipelines for petroleum running through permafrost areas as Trans-Alaska-Pipeline are often run overhead in order to avoid melting the frozen ground by hot petroleum which would result in sinking the pipeline in the ground.

Regulation

In the US, onshore and offshore pipelines used to transport oil and gas are regulated by the Pipeline and Hazardous Materials Safety Administration (PHMSA). Certain offshore pipelines used to produce oil and gas are regulated by the Minerals Management Service (MMS). In Canada, pipelines are regulated by either the provincial regulators or, if they cross provincial boundaries or the Canada/US border, by the National Energy Board (NEB). Government regulations in Canada and the United States require that buried fuel pipelines must be protected from corrosion. Often, the most economical method of corrosion control is by use of pipeline coating in conjunction with cathodic protection and technology to monitor the pipeline. Above ground, cathodic protection is not an option. The coating is the only external protection.

Pipelines and geopolitics

Pipelines for major energy resources (petroleum and natural gas) are not merely an element of trade. They connect to issues of geopolitics and international security as well, and the construction, placement, and control of oil and gas pipelines often figure prominently in state interests and actions. A notable example of pipeline politics occurred at the beginning of the year 2009, wherein a dispute between Russia and Ukraine ostensibly over pricing led to a major political crisis. Russian state-owned gas company Gazprom cut off natural gas supplies to Ukraine after talks between it and the Ukrainian government fell through. In addition to cutting off supplies to Ukraine, Russian gas flowing through Ukraine—which included nearly all supplies to Southeastern Europe and some supplies to Central and Western Europe—was cut off, creating a major crisis in several countries heavily dependent on Russian gas as fuel. Russia was accused of using the dispute as leverage in its attempt to keep other powers, and particularly the European Union, from interfering in its "near abroad".

Oil and gas pipelines also figure prominently in the politics of Central Asia and the Caucasus.

Dangers

Accidents

Pipelines conveying flammable or explosive material, such as natural gas or oil, pose special safety concerns.

For a more complete list see List of pipeline accidents

As targets

Pipelines can be the target of vandalism, sabotage, or even terrorist attacks. In war, pipelines are often the target of military attacks, as destruction of pipelines can seriously disrupt enemy logistics.

See also

References

  1. ^ Andreas Oberhammer; The longest heat transfer pipeline in Austria Paper in German. Retrieved 2010-09-20
  2. ^ [1] Pell Research Report on Oil and Gas Pipeline Construction - cited with permission
  3. ^ go-devil - definition of go-devil by the Free Online Dictionary, Thesaurus and Encyclopedia.
  4. ^ a b James MacPherson (2007-11-18). "Ethanol makers consider coast-to-coast pipeline". USA Today. http://www.usatoday.com/money/industries/energy/2007-11-18-ethanolpipeline_N.htm. Retrieved 2008-08-23. 
  5. ^ a b John Whims (August 2002) (PDF). Pipeline Considerations for Ethanol. Kansas State University. http://www.agmrc.org/NR/rdonlyres/4EE0E81C-C607-4C3F-BBCF-B75B7395C881/0/ksupipelineethl.pdf. Retrieved 2008-08-23. 
  6. ^ "Ethanol pipeline places the cart before the horse". The Daily Iowan. 2008-08-24. http://media.www.dailyiowan.com/media/storage/paper599/news/2008/07/24/Opinions/Ethanol.Pipeline.Places.The.Cart.Before.The.Horse-3394187.shtml. Retrieved 2008-08-23. 
  7. ^ "Project Profiles, Minas-Rio". 2010-12-12. http://www.bnamericas.com/project-profile/en/Minas-Rio-Minas-Rio. Retrieved 2010-12-12. 
  8. ^ "The Savage River Slurry Pipeline - The Australian Pipeliner". 2011-01. http://pipeliner.com.au/news/the_savage_river_slurry_pipeline/054155/. Retrieved 2011-05-07. 
  9. ^ "Savage River Pipeline Bridge - Highestbridges.com". 2009-12-17. http://www.highestbridges.com/wiki/index.php?title=Savage_River_Pipeline_Bridge. Retrieved 2011-05-07. 
  10. ^ Compressorless Hydrogen Transmission Pipelines
  11. ^ DOE Hydrogen Pipeline Working Group Workshop
  12. ^ Every 50 to 100 miles (160 km)
  13. ^ The Technological Steps of Hydrogen Introduction - page 24
  14. ^ a b Needham, Joseph (1986). Science and Civilization in China: Volume 4, Part 2. Taipei: Caves Books Ltd. Page 33.
  15. ^ Needham, Volume 4, Part 2, 345-346.
  16. ^ Mephan Ferguson Australian Dictionary of Biography(online version)
  17. ^ The Forrest family Dynasties, ABC. Retrieved 17 September 2006.
  18. ^ http://www.sawater.com.au/SAWater/WhatsNew/NewsRoom/Mannum+Adelaide+Celebrations.htm
  19. ^ Billie Ann Lopez. "Hallstatt's White Gold - Salt". Archived from the original on 2007-02-10. http://web.archive.org/web/20070210142713/http://www.virtualvienna.net/columns/billie/hallstatt/hallstatt.html. Retrieved 2007-05-15. 
  20. ^ See the article Hallstatt for details and references.
  21. ^ http://www.wtok.com/home/headlines/10946761.html

External links