Local Natural Gas Distribution Systems

(Photo: Unisource Energy Services)

If you’ve ever wondered where your natural gas comes from and how it gets to your house or business, here’s an example of how a local natural gas distribution system works. Regulations and construction requirements may differ from state to state.

Case Study: Local Natural Gas Distribution in Kingman, Arizona

Unisource Energy Services (UES) in Kingman, Arizona receives natural gas from the Transwestern Pipeline, which originates in Texas.  The steel transmission pipeline is 30 inches in diameter and operates at pressures from 200 to 1500 psi.  The pressure is reduced to 60 psi at UNS regulator stations and then reduced again to 0.25 psi before it enters the service lines that connect to home appliances (Unisource Energy Services, 2019; Energy Transfer, 2020).

In Arizona, there are four compressor stations along the Transwestern Pipeline at Klagetoh, Leupp, Flagstaff, and Seligman.  The compressors were built by USA Compression (Energy Transfer, 2020; USA Compression, 2020).

“Natural gas is compressed for transmission to minimize the size and cost of the pipe required to transport it” (Busby, 2017, p. 49).  Friction inside the pipe reduces the pressure and flow rate.  The gas is re-compressed at compressor stations in order to boost the pressure in the line.  Compressor stations are generally found every 50 to 100 miles along a pipeline.  They are a crucial part of the transport system that keeps the natural gas flowing through the pipe at the right pressure and flow rate.  Air is mixed in with the gas to lower emissions from the compressor stations (Busby, 2017, p. 49, 51).

Reciprocating compressors use high compression ratios but have limited capacities.  They are driven by internal combustion natural gas engines (Busby, 2017, p. 49).

Centrifugal compressors use lower compression ratios but have high capacities.  They rotate at 4,000 to 7,000 rpm and are driven by natural gas turbines.  They are energy efficient and cost less to install and use (Busby, 2017, p. 49-50).

The Transwestern Pipeline has an interconnect point at Kingman, Arizona, at legal description 21 N, 16 W, in Section 19.  There is a measuring station there that measures the amount of gas delivered to the Kingman interconnect (Energy Transfer, 2020).

Transwestern utilizes all types of meters in its measuring stations: orifice meters to measure gas received or delivered at an interconnect; turbine meters or ultrasonic meters to measure displaced gas; and coriolus meters, all according to the AGA Gas Measurement Manual (Energy Transfer, 2020).

“Metering of gas flow is an important function of pipeline gas operations” (Busby, 2017, p. 51) because customers along the line pay for the amount of natural gas they receive.  Meters must be accurate in order to ensure accurate and reliable billing (Busby, 2017, p. 49).

Many natural gas companies handle seasonal demand by storing natural gas in underground facilities or storing it as liquefied natural gas (LNG).  “Peak shaving is one of the most common domestic uses for LNG today” (ADI Analytics, 2015).  When seasonal demand (usually in the winter) requires a bigger load of natural gas, the “LNG is regasified and sent to the distribution pipelines” (Maverick Engineering, 2016).

Natural gas supplies can also be augmented with synthetic natural gas (SNG) during seasonal demand.  SNG is actually propane-air or liquefied petroleum gas air (LP-air) which “is created by combining vaporized LPG with compressed air” (Transtech Energy, 2020).  During seasonal demand, peak shaving facilities inject SNG into the natural gas distribution system to augment the real natural gas in order to meet increased demand (Transtech Energy, 2020).

Another way to increase the natural gas supply during peak demand is line packing.  This requires installing oversized pipes in transmission lines, which is incredibly expensive, and not always worth the cost (INGAA Foundation, 1996).

Unisource Energy Services has no storage facilities so it must plan ahead and estimate how much natural gas it will need to meet the winter peak demand.  Then it must contract with a reliable natural gas supplier, schedule the deliveries, and submit its Gas Supply Plan to the Arizona Corporation Commission.  This arrangement is called an asset management agreement (AMA) (American Gas Association, 2019; Arizona Corporation Commission, 2017).

As local natural gas distribution companies grow, they must install new lines to accommodate new customers.  The state of Arizona requires that all excavations be reported to the state at least 2 days before the actual trenching.  All utility lines must be discovered and clearly marked.  Only manual digging can be used within 24 inches of marked lines (Arizona 811, 2020).  These requirements were put in place for safety reasons, to prevent damage to buildings and injuries to humans.

Joint trench requirements can differ from city to city, county to county, and state to state. But a typical safe guideline is as follows: a trench at least 36 inches deep and 18 inches wide; 24 inches between gas and electric lines and between natural gas and water lines; 12 inches between natural gas and communication lines; 24 inches between natural gas and sewer lines (Arizona Public Service Electric, 1995; Lane Electric Cooperative, 2020).

Unisource Energy Services is required by law to follow state and local construction requirements and trenching laws.  The company uses plastic pipes 0.5 to 8 inches in diameter and coated steel pipes 0.75 to 16 inches in diameter (Unisource Energy Services, 2019).  Like all natural gas companies, company engineers must consider line pressures, the length of the line, and estimated load when deciding which pipes to use.

References

ADI Analytics. (2015). A new role for small-scale and peak shaving lng infrastructure.

       Retrieved from https://www.adi-analytics.com/2015/06/03/a-new-role-for-small-scale-and-

       peak-shaving-lng-infrastructure/

American Gas Association. (2019). LDC supply portfolio management during the 2018-2019

       winter heating season. Retrieved from

Click to access whs-2018-2019-report-final-12-20_2019-.pdf

Arizona 811. (2020). Proper planning. Retrieved from https://www.arizona811.com.

Arizona Corporation Commission. (2017). Winter preparedness. Retrieved from

https://www.azcc.gov/docs/default-source/utilities-files/gas/winter-preparedness-2017/uns-

       gas-2017-winter-prepardness.pdf?sfvrsn=daa79b6f_2_.

Arizona Public Service Electric. (1995). Trenching requirements. Retrieved from

https://www.aps.com/en/About/Construction-and-Power-Line-Siting/Construction-Services.

Busby, R.L. (Ed.). (1999). Natural Gas in Nontechnical Language. Tulsa, OK: PennWell.

Energy Transfer. (2020). Natural gas. Retrieved from

https://www.energytransfer.com/natural-gas.

INGAA Foundation. (1996). The use of liquefied natural gas for peaking service. Retrieved from

https://www.ingaa.org/File.aspx?id=21698.

Lane Electric Cooperative. (2020). Typical trench detail. Retrieved from

Programs & Services

Maverick Engineering. (2016). Oil & gas: LNG: Peak shaving facilities. Retrieved from

https://www.maveng.com/index.php/business-streams/oil-gas/lng/peak-shaving-facilities.

Transtech Energy. (2020). SNG peak shaving system design & implementation. Retrieved from

https://www.transtechenergy.com/peak-shaving-systems.

Unisource Energy Services. (2019). Construction services. Retrieved from

Construction Services

USA Compression. (2020). Gas compression. Retrieved from

Gas Compression

Dawn Pisturino

Thomas Edison State University

November 19, 2020; April 18, 2022

Copyright 2020-2022 Dawn Pisturino. All Rights Reserved.

History of Chevron Corporation

(Standard Oil Company of California gas station)

       In September 1876, oil driller Alex Mentry struck oil at Pico No. 4 in Pico Canyon, California.  This set off a new “gold rush” in search of oil, the “black gold.”  At the time, Mentry worked for California Star Oil.  A few years later, on September 10, 1879, Pacific Coast Oil Company, which had incorporated in San Francisco, California on February 19, 1879, acquired California Star Oil – and this is where the history of Chevron begins (Chevron, 2020).

       Pacific Coast built the largest refinery in California at Point Alameda on San Francisco Bay, with the capacity to produce 600 barrels a day.  The company built a pipeline from Pico Canyon to the Southern Pacific Railroad train station at Elayon in southern California. By 1895, they had acquired the first steel tanker in California, the George Loomis, which could hold 6,500 barrels of crude oil (Chevron, 2020).

       In 1878, competition appeared in the form of Standard Oil Company (Iowa).  Known for its marketing skills, quality products, effective advertising campaigns, and rich financial backing, it set up shop in San Francisco, California with the goal of dominating the West Coast’s oil market.  By 1885, Standard Oil had distribution centers throughout the West Coast.  By contrast, Pacific Coast Oil Company was struggling to survive. Finally, in 1900, Standard Oil purchased the struggling company in order to increase its own production, transportation, and refining operations. In 1906, consolidation between Pacific Coast Oil and Standard Oil (Iowa) produced a new company – Standard Oil of California (Chevron, 2020).

       In 1911, Standard Oil of California established the California Natural Gas Company at its El Segundo plant in southern California in order to explore for natural gas in the San Joaquin Valley.  A second pipeline was built, linking the Richmond refinery, which was built in 1902, and the Kern River Field (Chevron, 2020).

       In an effort to conserve energy resources, the Starke gas trap – invented by engineer C.C. Scharpenberg and geologist Eric Starke — was invented and implemented for capturing natural gas from a well (Chevron, 2020).

       Between 1912 and 1919, Standard Oil of California expanded its operations until it saturated the market in a five-state area.  “Petroleum and natural gas are by far the major fuels used on the Pacific Coast” (Miller, 1936, p. 86).  But its market share had dropped by 1926 due to increased competition.  With the re-opening of the Panama Canal in 1914, Standard Oil of California ventured into the international market and expanded its market share in the Eastern United States and Europe (Chevron, 2020).  Natural gas use, however, continued to grow, from 72,000 cubic feet consumed on the West Coast in 1921 to 258,000 cubic feet consumed in 1933 (Miller, 1936, p. 86).

       Standard Oil of California continued to expand its operations through subsidiaries, mergers, and partnerships.  It opened operations in the Middle East, Canada, Mexico, and Central America.  In September 1950, the company completed the Trans-Arabian Pipeline.  Company revenues reached 1 billion dollars in 1951.  A merger with Standard Oil of Kentucky in 1961 expanded its markets in five southeastern states.  In 1977, Chevron USA was formed with the merger of six domestic oil and gas operations.  In 1979, Chevron celebrated 100 years of operations (Chevron, 2020).

       In March 1984, Chevron merged with Gulf Oil Corporation.  This merger increased their reserves of oil, gas, and natural gas liquids.  In the 1990s, Chevron developed the Escruvos

Natural Gas project in Nigeria, converting natural gas to liquids.  In 1996, “Chevron transferred its natural gas gathering, operating, and marketing operation to NGC Corporation (later Dynergy) in exchange for a roughly 25% equity stake in NGC” (Chevron, 2020). Through its merger with Texaco, Chevron acquired 11 million oil-equivalents of natural gas reserves.  Using 3-D imaging signals, Chevron discovered one of the largest crude oil and natural gas fields in the U.S. Gulf of Mexico in May 2009.  In 2005, Chevron changed its name to Chevron Corporation, acquired Unocal, and increased its natural gas reserves by 15 per cent.  The Gorgon Project and Wheatstone Project in Western Australia are boosting Chevron’s liquefied natural gas reserves. Gorgon, which will supply the Asia-Pacific market, had a daily production of 2.3 billion cubic feet of natural gas and 6,000 barrels of condensate in 2019.  Production is projected to last 40 or more years, with 15.6 million metric tons of liquefied natural gas produced per year (Chevron, 2020).

       “Chevron’s development of oil and natural gas from shale and tight rock formations has intensified since the company entered the Marcellus Shale through its acquisition of Atlas Energy in 2011” (Chevron, 2020).  The company’s policy of partnerships, mergers, and acquisitions has paid off handsomely for its bottom line and future success.

       Likewise, experts say that energy demand could increase by 33% by the year 2040, making all sources of energy important: natural gas, crude oil, coal, renewables, and nuclear (Chevron, 2020).  California alone “produced more than 200 million cubic feet of natural gas in 2017 used for heating and cooking in homes and businesses and to generate electricity” (Powering California, 2019).  Chevron has expanded into geothermal, solar, wind, biofuel, fuel cells, and hydrogen energy.  It recently invested in Carbon Clean Solutions, a company which is developing technology that “removes carbon dioxide at a price of $30.00 per ton” (Houston Chronicle, 2020.)  The prototype is expected to come out in 2021.

       The demand for natural gas and liquefied natural gas has intensified as companies and consumers look for cleaner, cheaper sources of energy.  Liquefied natural gas (LNG) can be easily shipped and stored because cooling the gas at temperatures of -260 degrees Fahrenheit shrinks the gas into 600 times smaller its normal volume.  LNG can be re-gasified and transmitted through natural gas pipelines to power plants fueled by natural gas, as well as industrial, residential and commercial consumers.  Markets for both natural gas and LNG have increased in the U.S. since 2007, and Asian countries are demanding more imported product (U.S. Energy Information Administration, 2020).  Chevron Shipping Company has a large fleet of crude oil tankers and LNG carriers to meet this demand (Chevron, 2020).

       Chevron has crude oil and natural gas fields in Colorado, New Mexico, and Texas. In 2018, they produced 651 million cubic feet of natural gas and 77,000 barrels of natural gas liquids (NGL).  In 2018, Chevron’s holdings in the Gulf of Mexico produced 105 million cubic feet of natural gas and 13,000 barrels of NGLs. Its Jack and St. Malo fields produced 139,000 barrels of liquids and 21 million cubic feet of natural gas. Its Big Foot Project produced 25 million cubic feet of natural gas per day. Its Tahiti field in the Gulf produced 22 million cubic feet of natural gas and 3,000 barrels of NGLs.  Its Mad Dog Field yielded 8,000 barrels of liquids and 1 million cubic feet of natural gas.  The Stampede Field produced 4 million cubic feet of natural gas. In California, 25 million cubic feet of natural gas and 400 barrels of NGLs were produced.  In the Appalachian Basin, 240 million cubic feet of natural gas, 4,000 barrels of NGLs, and 1,000 barrels of condensate were produced (Chevron, 2020).

       “The Chevron Pipe Line Company transports crude oil, refined petroleum products, liquefied petroleum (LPG), natural gas, NGLs, and chemicals within the U.S.” (Chevron, 2020).  It manages pipelines for Chevron Phillips Chemical and has financial interests in other U.S. and international pipelines.  Chevron Power and Energy Management Company handles gas-fired and renewable energy power generation.  Cogeneration facilities fueled by natural gas produce electricity and steam and re-use recovered waste heat to optimize oil operations.  Chevron’s Supply and Trading branches in Houston, Texas, London, Singapore, and San Ramon, California provide support for crude oil and natural gas production operations, refining, and marketing. Approximately 5 million barrels of liquids and 5 billion cubic feet of natural gas are traded on the commodities exchange every day.  Chevron’s Gas Supply and Trading group “markets and manages transportation for Chevron’s equity natural gas production.  It also manages all LPG and NGL trading, including supplying refineries and marketing NGLs produced by Chevron’s refineries and Upstream assets” (Chevron, 2020).

       In order to ensure a qualified work force for the future, Chevron invests in education to teach high school students science, technology, engineering, and mathematics (STEM).  Geologists, chemists, IT specialists, healthcare workers, engineers, and other specialists working for Chevron must be experienced professionals in their fields.  They actively encourage girls to become proficient in STEM.  And they support programs to help low-income men and women get the skills they need to get high-paying jobs in the global energy industry (Chevron, 2020).

       More than 100 years later, Chevron is exploring, researching, developing, and utilizing new technologies in order to meet increasing demands for energy.  It continues to be a leader in the global energy industry.

Dawn Pisturino

Thomas Edison State University

December 16, 2020

Copyright 2020-2022 Dawn Pisturino. All Rights Reserved.

References

Chevron. (2020). History: see where we’ve been and where we’re going. Retrieved from

https://www.chevron.com.

Chevron. (2020). Operations: driving human progress. Retrieved from

https://www.chevron.com.

Chevron. (2020). Project portfolio: delivering energy worldwide. Retrieved from

https://www.chevron.com.

Houston Chronicle. (2020). Chevron invests in carbon capture technology company. Retrieved

       from https://www.houstonchronicle.com/business/energy/article/Chevron-invests-in-carbon-

       capture-technology-15063229.php.

Miller, W. (1936). Pacific Coast Oil and Natural Gas. Economic Geography, 12 (1), 86-90.

       doi: 10.2307/140266.

Powering California. (2019). The history of oil and natural gas in california. Retrieved from

https://www.poweringcalifornia.com/the-history-of-oil-and-natural-gas-in-california-2/

U.S. Energy Information Administration. (2020). Natural gas explained. Retrieved from

https://www.eia.gov/energyexplained/natural-gas.

Evolution of Natural Gas in America

The natural gas industry is so vital to the functioning and prosperity of the United States that a depletion of natural gas resources would cripple the whole country.  Roughly 25% of the energy used in the United States comes from natural gas.  From manufacturing uses to home energy consumption, natural gas plays an important role in everyday life, even if American consumers are unaware of it (Busby, 1999, p. xviii).

       Natural gas is a natural resource that has developed over millions of years of plant and animal decomposition.  It is often found at the bottom of bodies of water that have existed for eons, such as oceans and lakes.  Plant and animal matter that became buried before decomposition or became lodged in anaerobic water, such as a stagnant pond, avoided oxidation.  As sand, mud, and other materials collected on top of the organic matter over long periods of time, these materials solidified into rock.  The organic matter was preserved by the rock. Years and years of pressure and heat turned the organic matter into gas and oil.  “Coal, shale, and some limestones have a dark color that comes from their rich organic content.  Many sedimentary basins are gas-prone and produce primarily natural gas” (Busby, 1999, p. 2-3).

       The average composition of natural gas, after processing, is 88% methane, 5% ethane, 2% propane, and 1% butane (Busby, 1999, p. 2).  The natural gas widely used today is, therefore, largely methane, “a colorless, odorless gas that burns readily with a pale, slightly luminous flame (Busby, 1999, p. 1).  The by-products of burning natural gas are mostly water vapor and carbon dioxide, making it “the cleanest burning fossil fuel” (Busby, 1999, p. 1).

       Methane is used in making solvents and other chemical compositions.  Propane and butane are separated from natural gas and sold as separate fuels. Liquified petroleum gas (LPG) is mostly propane and used as a fuel in rural areas where pipelines do not exist.  When carbon dioxide and helium are recovered from natural gas, they are often used to boost production in old oil fields.  Helium that is recovered from natural gas is used to fill balloons and blimps.  It is also widely used in the electronics industry.  Hydrogen sulfide, which is very corrosive, must be removed from natural gas before it is transmitted through pipelines or it will damage vital parts of gas wells and pipes (Busby, 1999, p. 1-2).

       Wood that has been subjected to high temperatures over time, turns into coal.  Coal seam gas is primarily methane. At depths with cooler temperatures, bacteria produce microbial gas, which is largely methane. Thermogenic gas develops at lower depths and with temperatures greater than 300 degrees Fahrenheit.  Trapped in underground reservoirs, high temperatures sometimes “gasify” the heavier hydrocarbons.  When the temperature cools, the gas re-liquifies and forms a condensate, which is largely pure gasoline. This is known as “wet” gas.  “Dry” gas is composed of pure methane.  Natural gas liquids (NGL) are composed of butane, propane, ethane, and gasoline condensate.  At depths greater than 18,000 feet, high temperatures turn oil into natural gas and graphite (Busby, 1999, p. 3-4).

       “Most deep wells are drilled in search of natural gas . . . [because] most gas that has been generated over the ages has been lost rather than trapped, which is why many exploratory wells are unproductive” (Busby, 1999, p. 3-4).  The reservoir rock holding the gas must be porous as well as permeable to allow for containment and access.

       Although people in the past were aware of natural gas, it was not until the 1800s that gas began to be developed and used for various purposes.  Coal gas began to be utilized in gas lighting in America and Europe, which allowed factories and businesses to operate for longer hours and families to engage in more social activities in the evenings (Busby, 1999, p. 5-6).

       One of the first inventors to experiment with coal gas was William Murdoch.  His experiments were so successful that his employer, Boulton & Watt, expanded its business to include “installing gas lighting in English factories” (Busby, 1999, p. 6).  The city of Birmingham adopted gas lighting, which inspired great demand for this new technology (Busby, 1999, p. 6).

       One of the first gas lights, the Thermolamp, was invented by Philippe Leon in France in 1799.  He patented a process to generate gas from wood and put it on display in Paris in 1802.  But the French government rejected the idea of a massive lighting system fueled by gas (Busby, 1999, p. 6).

       In 1807, Frederick Winsor “staged the first gas street-lighting display in London” (Busby, 1999, p. 6).  He had found a way to pipe large quantities of gas via a centralized system and founded his own public gas distribution company in 1812 (Busby, 1999, p. 6).

       By 1819, London had installed approximately 300 miles of gas pipes that supplied more than 50,000 gas burners.  The pipes were made of wood, but these were eventually replaced by metal pipes (Busby, 1999, p. 6).                                                                                                                                        

       In America, Charles Peale began testing gas lighting in Philadelphia in 1802.  The city of Baltimore hired his son, Rembrandt Peale, to install a gas lighting system in 1816.  The first gas utility company in America was born in that year, and more sprouted up along the East coast.  The first gas company in the southern states was established in New Orleans (Busby, 1999, p. 6).

       America could boast around a thousand companies selling coal gas for lighting by the end of the 19^th century.  And most major cities around the world had adopted gas lighting (Busby, 1999, p. 6).

       Most consumer gas distribution was not metered but delivered at a flat rate, which was based on the number of hours of use and the number of lights in a household or business.  A gas meter was invented in 1815.  By 1862, gas meters – which monitor the volume of gas used – were being used in London.  Coin-operated meters became available in the 1890s which allowed poorer consumers to utilize gas energy as they could afford it (Busby, 1999, p. 7).

       “Coke is a solid, porous by-product of gas manufacturing that can also be used for domestic heating” (Busby, 1999, p. 8).  The evolution of the iron and steel industries created a demand for blast-furnace coke that led to the development of the push-through-coke oven.  The demand for coke oven gas increased until it “constituted 18.7% of all manufactured gas” (Busby, 1999, p. 8) in 1920.

       As new uses for gas were discovered, developed, and implemented, “the first gas range in the U.S. was built around 1840” (Busby, 1999, p. 8).  The Goodwin Company introduced the Sun Dial Stove in 1879.  Two more gas stove manufacturers opened within four years.  And in 1887, the first gas appliance store opened in Providence, Rhode Island.  By 1900, cooking with gas had outstripped gas lighting and gas heating (Busby, 1999, p. 8).                                                                                                            

       Using gas to heat water storage tanks became popular in the 1860s.  The year 1883 saw the first circulating water heater come onto the market.  A water heater with a thermostat was introduced a few years later. Gas distribution was fast becoming a household necessity (Busby, 1999, p. 9).

       Natural gas was frequently discovered in the 1800s when people drilled for water, but the gas was ignored.  It was not until 1821 that William Hart drilled the first natural gas well and piped it through wooden pipes to neighbors’ homes.  This same gas was used to light up the City of Fredonia, New York a few years later (Busby, 1999, p. 9).

       Gas wells were drilled in Pennsylvania, New York, and West Virginia throughout the 1830s and 1840s.  But gas pipes were still primitive and only able to transport gas to customers near the gas wells (Busby, 1999, p. 10).

       The first natural gas company opened in Fredonia, New York in 1865.  When oil was discovered in Titusville, Pennsylvania, an oil rush ensued that diminished the importance of natural gas.  “Gas produced along with oil was usually just burned off, or flared” (Busby, 1999, p. 10).

       Andrew Carnegie, the famous steel magnate, documented in 1885 that 10,000 tons of coal had been replaced by natural gas.  But as the supply of natural gas became depleted, steel makers were forced to revert to using coal again by 1900.  This pattern repeated itself for the next 25 years.  Wastefulness and leakage were the main culprits (Busby, 1999, p. 10).

       The first long-distance wooden pipeline was built between West Bloomfield and Rochester, New York in the 1870s when a large reservoir of natural gas was discovered in West Bloomfield.  The gas was transported through this 25-mile pipeline (Busby, 1999, p. 10).

       Indiana Gas and Oil Company laid a 120-mile parallel pipeline made of wrought iron in 1891 that used high pressure (525 psi) to transmit natural gas to Chicago from the gas field in Indiana.  The company started using manufactured gas when the natural gas supply ran out in 1907 (Busby, 1999, p. 10-11).

       Oxyacetylene welding was invented in 1911 which sped up development of seamless steel pipe in the 1920s.  Natural gas could now be transmitted at higher pressures and in larger quantities and to longer distances, which boosted profitability for natural gas companies and helped them compete with other fuels.  The natural gas industry continued to expand until the Great Depression, which slowed down economic activity across the country.  As soon as World War II was over and the economic climate improved, the industry began to boom again (Busby, 1999, p. 11-12).

       Natural gas is one of the main fuels used in the food processing industry in the United States.  Large boilers are used to create process steam, which is used in “pasteurization, sterilization, canning, cooking, drying, packaging, equipment clean-up, and other processes” (Busby, 1999, p. 87). Natural gas energy saves companies money when they install “high-efficiency, low-emission natural gas-fired boilers” (Busby, 1999, p. 87). 

       Large amounts of hot water are also needed for “cleaning, blanching, bleaching, soaking, and sterilization” (Busby, 1999, p. 87).  High-efficiency industrial water heaters are used routinely in food processing.  Gas appliances are also used for “drying, cooking, and baking, as well as for refrigeration, freezing, and dehumidification” (Busby, 1999, p. 87).

       Tyson Foods has made a commitment to reduce energy use and produce fewer emissions that puts them at the top of the food processing industry.  As of 2019, they were using 42.15%

non-renewable fuels (including natural gas), 15.72% electricity, and 0.45% renewable energy (wind and solar power).  They are using renewable fuels like biogas from their waste treatment plants in their plant boilers in order to reduce their natural gas use.  They used about 666 million cubic feet of biogas in their boilers in 2019.  Although their energy use went up in 2019, their emissions went down.  The company is reusing process water in their plants to reduce water use.  And it is considering natural gas, electrification, and hydrogen fuel for their transportation fleet (Tyson Sustainability, 2019).

       “Natural gas . . . is the cleanest burning fossil fuel, and emits very few pollutants into the atmosphere” (Natural Gas, 2013).  Although Tyson is already using natural gas in its plants, it might want to consider using natural gas to generate its own electricity in order to free itself from dependency on local electric companies.  This could save them money in the long run, especially as electricity rates go up and electricity delivery reliability goes down.  This, however, would require a large capital investment that Tyson might not want to make (Natural Gas, 2013).

       But Tyson is already using boilers that produce steam, and this steam could be used to generate electricity.  If the boiler keeps running, “the steam can be diverted to a turbine for generating power” (Busby, 1999, p. 87-88).  This is called cogeneration because “waste heat is recovered and used” (Busby, 1999, p. 87).

       Although most power plants have been fueled by coal, there has been a push towards using natural gas because this reduces emissions of sulfur dioxide, nitrogen oxides, soot, and smoke (Busby, 1999, p. 88).  “Natural gas can be used to produce electricity either directly, in a gas-powered turbine, or indirectly, in a steam-powered turbine (using steam from a gas-fired boiler)” (Busby, 1999, p. 89).  The natural gas also serves to increase boiler efficiency.

       Natural gas demand is expected to increase in the future as consumers expect energy efficiency regulations to reduce emissions in the atmosphere and industries are pressured to use low-carbon fuels.  Natural gas is a clean, reliable, and efficient energy source that can be used with confidence in the residential, commercial, and industrial settings.

Dawn Pisturino

Thomas Edison State University

October 14, 2020

Copyright 2020-2022 Dawn Pisturino. All Rights Reserved.

References

Busby, R.L. (Ed.). (1999). Natural Gas in Nontechnical Language. Tulsa, OK: PennWell.

Natural Gas. (2013). Natural gas and the environment. Retrieved from

       http://www.naturalgas.org

Tyson Sustainability. (2019). 2019 sustainability report. Retrieved from 

https://www.tysonsustainability.com/environment/energy-emissions.

.

The Basics of Gas Exploration, Production, and Distribution

Offshore natural gas drilling

The Basics of Gas Exploration, Production, and Distribution

Gas and oil traps are formed by geological events such as tectonic plate shifting, glacier movement, and extreme temperature changes. As long as the gas cannot escape from the area, it will be trapped in place (Blewett, 2010).

When reservoir rock is subjected to high pressure and other conditions, it can become fractured or deformed, creating a space that can fill up with oil or natural gas. Anticlines are structural traps which occur when layers of rock are pushed upward, causing an arch. Synclines occur when the rock is pushed downward. Domes are similar to anticlines but have a more rounded appearance (Busby, 1999).

Faults occur when rocks crack due to outside forces and sections, or plates, slide out of alignment. Sections of rock can slide upward (dip-slip) or sideways (strike-slip). Thrust faults appear on the earth’s surface as mountain ranges. Fractures can divide traps into smaller compartments and increase the permeability of sedimentary rocks. Shales and chalks are normally porous and impermeable. When fracturing occurs, it can make these rocks more permeable, making it possible for gas to get trapped inside the rocks (Busby, 1999).

Stratigraphic traps are harder to access than structural traps because the gas and oil have been trapped within the layers of rock. These traps form as the result of changes in the porosity and permeability of the rock due to the way in which sediment has been deposited. Gas cannot escape the rock. Large fields of gas and oil can be trapped in this way (Busby, 1999).

Combination traps have the characteristics of both structural and stratigraphic traps. A salt dome occurs when a large quantity of salt gets trapped in sedimentary layers and breaks through the earth’s surface, forming “a plug-like structure” (Busby, 1999).

Carbonate rock reservoirs formed when ancient caves collapsed, causing fractures in the rocks. A new cave system was created, forming a reservoir for gas and oil to be trapped inside (Busby, 1999).

In order for any oil or gas field to be productive, there must exist the right combination of “reservoir rock, trap, and cap rock or other seal” (Busby, 1999). There must be “source rock that has generated gas or oil, reservoir rock to hold the gas, a trap to seal it off, and the right timing” (Busby, 1999). Without a trap in place, the gas will disperse out of the area (Busby, 1999).

The largest producing gas fields in the United States are as follows:

Marcellus Shale is an unconventional shale formation which stretches beneath two-thirds of Pennsylvania and parts of New York, Ohio, West Virginia, Maryland, Kentucky, and Virginia. This area is estimated to hold 6 trillion cubic feet of natural gas.  The most productive wells lie 5,000 to 8,500 feet below the earth’s surface (Pennsylvania Department of Environmental Protection, 2020).

This natural gas can only be accessed through vertical and horizontal drilling and the use of hydraulic fracturing (fracking). The Pennsylvania Department of Environmental Protection inspects and monitors these wells “from construction to reclamation to ensure that the site has proper erosion controls in place, and that any waste generated in drilling and completing the well was properly handled and disposed. Also, unconventional well operators are required to submit a variety of reports regarding well drilling, completion, production, waste disposal, and well plugging” (Pennsylvania Department of Environmental Protection, 2020).

The Newark East gas field in Texas is composed of Barnett Shale. Currently, 5,600 wells and 150 rigs are in operation. The field is estimated to hold 1,951 billion cubic feet of natural gas (Geo ExPro, 2007; Oil Price, 2015).

The B-43 Area in Arkansas is estimated to hold 1,025 billion cubic feet of natural gas, but not much other information was available (Oil Price, 2015).

The San Juan Basin is found in Colorado and New Mexico. It is estimated that the field holds 1,024 billion cubic feet of natural gas. Not much other information was available (Oil Price, 2015).

The Haynesville/Bossier Shale formation is located in eastern Texas and western Louisiana. The natural gas is found at depths greater than 10,000 feet below the earth’s surface. The area is producing 2,680 million cubic feet per day of natural gas and 420 barrels per day of condensate (Railroad Commission, 2020).

The Pinedale gas field in Wyoming is the sixth largest gas field in the United States. It covers 70 square miles. Its layers of sandstone are 6,000 feet thick and form a 30-mile anticline. Operators use horizontal drilling to access the natural gas. In 2015, it produced 4 million barrels of gas condensate and 436 billion cubic feet of natural gas. Its gas reserves hold 40 trillion cubic feet of natural gas—enough to provide energy to the entire country for 22 months (American GeoSciences, 2018).

The Carthage natural gas field near Carthage, Texas produced 13,912,377 million cubic feet of natural gas in June 2020. Not much other information was available (Texas Drilling, 2020).

The Jonah field is located south of Pinedale, Wyoming. It covers 21,000 acres and is estimated to hold 10.5 trillion cubic feet of natural gas. Chevron is one of the energy companies involved in both Jonah and Pinedale (Wyoming History, 2014).

The Wattenberg field covers 180,000 acres in Colorado. Horizontal wells are drilled to access the natural gas. It has a complicated geological structure due to “crustal basement rock weakness [ caused by super-heated] organic Niobrara source rocks” (PDC Energy, 2020).

Prudhoe Bay in Alaska has been producing oil and gas for 40 years. It covers 213,543 acres and holds 46 trillion cubic feet of natural gas (NS Energy, 2020). Pump station 1, at the beginning of the Trans-Alaska Pipeline, is situated within the Prudhoe Bay field. The natural gas is held in place by “an overlying gas cap and in solution with the oil” (Department of Environmental Conservation, 2020). The Alaska LNG project will be using natural gas from the Prudhoe Bay field to produce liquefied natural gas (NS Energy, 2020).

The most common technique for drilling wells is rotary drilling because “it can drill several hundreds or thousands of feet in a day” (Busby, 1999). A long piece of steel pipe with a drill bit on the end is suspended from a rig and driven into the ground by a diesel engine. The rotating bit drilling into the earth “creates the wellbore or borehole” (Busby, 1999). The bit must be changed after 40 to 60 hours of drilling.

Directional drilling is being used more commonly now to access oil and natural gas in unconventional traps (tight formations). Rotary rigs can now drill in many different directions to reach gas in multiple areas, drill offshore, or drill under populated areas (Busby, 1999).

Horizontal drilling can increase the recovery of natural gas “from a thin formation . . . a low-permeability reservoir . . . isolated productive zones . . . by connecting vertical fractures . . . prevent production of excessive gas or water from above or below the reservoir . . . to inject fracturing fluids” (Busby, 1999).

Offshore drilling is more expensive because the average rig drills down to around 10,400 feet. “An offshore exploratory rig must be able to move across the water to different drilling sites” (Busby, 1999).

Drilling barges are used in shallow waters. Jack-up rigs can be raised or lowered and drill down to a depth of 350 feet. A semisubmersible platform floats on pontoons and anchors at the drilling site. These platforms can drill down to 2,000 feet. Drill ships float over the drill site and can drill down to almost any depth (Busby, 1999).

Once a productive field has been discovered, a fixed or a tension-leg platform is permanently anchored at the site. The legs on fixed platforms can be anchored with piles driven into the ocean floor; whereas, tension-leg platforms float above the field and are anchored by “steel tubes connected to heavy weights on the sea floor” (Busby, 1999).

Drilling a dry hole can be one of the biggest expenses associated with drilling wells. More common issues include something breaking inside the well or objects falling into the hole. Drilling must then be stopped and the problem corrected (Busby, 1999).

Pressures become higher as the rig drills deeper. When this occurs, gas and water “can flow into the well, dilute the drilling mud, and reduce its pressure” (Busby, 1999). When the flow of fluids is uncontrolled, this is called a blowout.

“Natural gas is produced from most reservoirs by expansion, where the pressure of the expanding gas underground forces it into the well” (Busby, 1999). When the pressure drops in the well, gas production decreases. It can be stimulated with the use of a compressor (Busby, 1999).

Once the gas has been purified and processed, it is transported through pipelines from the gas field to distribution companies and industrial customers. Compressor stations along the line maintain the pressure needed to keep the gas flowing smoothly through the pipe. The gas flow is measured at the beginning and end of each pipe section, at each compressor station, and each intersection where the pipe branches off into two pipelines. Large industrial customers receive natural gas directly to their facilities, which “requires high-volume meters” (Busby, 1999).

Economically, it is essential to measure natural gas flow accurately at all points of the supply chain because “an error of 1% in measuring 300 million ft3 of gas per day can lead to a difference of about $2 million per year” (Emerson, 2016). After all, customers pay for the amount of energy delivered.

Differential pressure (DP) meters “measure volumetric flow through a calibrated orifice (generally a plate), are inexpensive, and simple in concept” (Emerson, 2016). Measurements must be corrected for density (mass), temperature, pressure, and gas composition. DP meters are not as acceptable as more advanced technologies (Emerson, 2016).

Ultrasonic meters measure volumetric flow rates by measuring “speed and sound in the gas” (Emerson, 2016). They have an accuracy of 0.35% to 0.5%. Some are available with an accuracy of 0.25% (Emerson, 2016).

Coriolis meters “measure mass flow and density” (Emerson, 2016) but temperature, pressure, and gas composition still need to be measured. These meters tend to be rather expensive (Emerson, 2016).

Flow computers “measure, monitor, and may provide control of gas flow for all types of meters” (Emerson, 2016). They record data from volumetric flow measurement, temperature, gas composition, and density in order to calculate flow rate. Every calculation is dated and timed (Emerson, 2016).

Shale gas is usually composed of less than 50% methane and roughly 50% of ethane, propane, butane, pentane and other gases. CO2, H2S, and sand can also be present. DP meters are excellent meters to use at the gas field site and when impurities are removed from the gas (Emerson, 2016).

Once the natural gas has been purified of water and CO2, the natural gas is processed through liquid separators and H2S separators. At this point, a Coriolis meter or ultrasonic meter is used (Emerson, 2016).

Ultrasonic meters are generally used on transmission pipelines, while Coriolis meters are used on distribution lines. To accurately calculate the Btus (British thermal units) per pound, a gas chromatography device is used (Emerson, 2016). One Btu equals “the energy released by burning a match” (U.S. Energy Administration, 2020).

Dawn Pisturino

Thomas Edison State University

October 30, 2020

References

American GeoSciences. (2018). The pinedale gas field, wyoming. Retrieved from

https://www.americangeosciences.org/geoscience-currents/pinedale-gas-field-wyoming.

Blewett, R.L. (Ed.) (1999). Shaping a Nation: A Geology of Australia. Canberra: Australia

       National University.

Busby, R.L. (Ed.). (1999). Natural Gas in Nontechnical Language. Tulsa, OK: PennWell.

Department of Environmental Conservation. (2020). Prudhoe bay fact sheet. Retrieved from

https://www.dec.alaska.gov/

Emerson. (2016). Selecting flow meters for natural gas fiscal measurement. Retrieved from

https://www.emerson.com/documents/automation/article-selecting-flow-meters-for-natural-

       gas-fiscal-measurement-daniel-en-us-177810.pdf.

Geo ExPro. (2007). Producing gas from shales. Retrieved from

https://www.geoexpro.com/articles/2007/03/producing-gas-from-shales.

NS Energy. (2020). Prudhoe bay oil field. Retrieved from

Prudhoe Bay Oil Field

Oil Price. (2015). The top 10 largest oil and gas fields in the united states. Retrieved from

https://www.oilprice.com/Energy/

PDC Energy. (2020). Wattenberg field. Retrieved from

https://www.pdce.com/operations-overview/wattenberg-field/

Pennsylvania Department of Environmental Protection. (2020). Marcellus shale. Retrieved from

https://www.dep.pa.gov/Business/Energy/Pages/default.aspx.

Railroad Commission. (2020). Haynesville bossier shale information. Retrieved from

https://www.rrc.state.tx.us/oil-gas/major-oil-and-gas-formations/haynesvillebossier-shale-

       information/

Texas Drilling. (2020). Carthage. Retrieved from

       http://www.texas-drilling.com/panola-county/carthage.

Wyoming History. (2014). Jonah field and pinedale anticline natural gas success story.

       Retrieved from https://www.wyohistory.org/encyclopedia/jonah-field-and-pinedale-

       anticline-natural-gas-success-story.

U.S. Energy Administration. (2020). British thermal units. Retrieved from

https://www.eia.gov/energyexplained/units-and-calculators/british-thermal-units.php.

Is Your House Sitting on an Ancient Gas Line Ready to Explode?

Richard Williams lived in an historic home in Shreveport, Louisiana. The home – and the cast iron natural gas main supplying the home – were built in 1911. The pipe cracked in 2016, allowing the gas to accumulate in a storage shed behind the home. Williams investigated a strong odor of gas in his backyard – with a lit cigar in his mouth – and the subsequent explosion killed him (Wooten & Korte, 2018).

An Internet search will reveal numerous natural gas explosions which have occurred over the last few decades as a result of ancient and faulty pipes. Since 1990, approximately 264 people have died due to natural gas accidents (Wooten & Korte, 2018).

In 1991, the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration began a program to mandate pipeline operators to replace cast iron natural gas pipes and to protect existing pipes from excavation. This has been a slow process because “the work is expensive, often difficult, and sometimes perilous” (Wooten & Korte, 2018).

Richard Williams and his neighbors had complained for a year about a terrible gas smell in the neighborhood. When Centerpoint Energy finally came out and fixed the service line which was connected to the gas main and the meter, they neglected to fill in the hole they had dug. The pipe began to leak again, and this was later attributed to “improper backfill” (Wooten & Korte, 2018) of the hole. Williams’ brother, a lawyer, contends that Centerpoint Energy and the city of Shreveport are at fault because they “were negligent in maintaining the gas pipes . . . [and it was] Centerpoint’s choice not to remove dangerous cast iron pipes from its system, even though Centerpoint knew just how deadly they were” (Wooten & Korte, 2018).

According to the United States Department of Transportation’s Pipeline and Hazardous Materials Safety Administration, “10% of the incidents occurring on gas distribution mains involved cast iron mains . . . [even though] only 2% of distribution mains are cast iron” (U.S. Department of Transportation, 2020).

Why are cast iron pipes so dangerous? Cast iron is vulnerable to graphitization, which makes the metal more brittle. Any kind of earth movement can cause the pipe to crack and start leaking. Furthermore, “cast iron pipelines were linked using bell and spigot joints with packing material stuffed in the bell to form a gas tight seal” (U.S. Department of Transportation, 2020). When dry gas replaced wet manufactured gas, the packing material dried out, causing leakage. Operators have used clamping and encapsulation to repair these joint leaks, but repairs do not solve the problem. Cast iron pipes – and other ancient pipes – need to be replaced altogether (U.S. Department of Transportation, 2020).

According to Wooten and Korte, “more than 53,000 miles of natural gas mains were built before 1940 . . . Decades of freezing and thawing, corrosion, vibration, and shifting soil can eat away at the cast iron and untreated steel pipes that were once the state of the art in natural gas distribution” (Wooten & Korte, 2018).

Other causes can include excavations by workers or homeowners; incorrectly installed pipes; incorrectly jointed pipes – and it can take years for the problem to become apparent and reach crisis dimensions. Approximately 85,000 miles of cast iron pipes and bare-steel pipes remain in service, posing a hidden danger to humans and structures alike (Wooten & Korte, 2018).

U.S. Department of Transportation. (2020). Cast and wrought iron inventory. Retrieved from

https://www.phmsa.dot.gov/data-and-statistics/pipeline-replacement/cast-and-wrought-iron-

       inventory/

Wooten, N. & Korte, G. (2018, November). Pipeline peril: Natural gas explosions reveal silent  

       danger lurking in old cast iron pipes. Shreveport Times. Retrieved from

https://www.shreveporttimes.com/story/news/2018/11/10/pipeline-peril-natural-gas-

       explosions-reveal-silent-danger-lurking-old-cast-iron-pipes/1924228002

Dawn Pisturino, RN

November 17, 2020

Copyright 2020-2021 Dawn Pisturino. All Rights Reserved.

Thomas Edison State University

NOTE: This is the kind of national infrastructure that Joe Biden and the Democrats should be concentrating on instead of playing politics with people’s lives and spending trillions of dollars on nonsensical wish list projects.