Liquefied Natural Gas

What is Natural Gas?

Natural gas is a fossil fuel primarily composed of methane (CH4). It also contains natural gas liquids (NGLs) and nonhydrocarbon gases like carbon dioxide and water vapor. Natural gas is formed from the remains of plants and animals that lived millions to hundreds of millions of years ago. These remains were subjected to heat and pressure over time, transforming them into coal, oil, and natural gas. Natural gas serves as a crucial component in residential, commercial, and industrial settings. In homes, it's commonly used for heating and cooking. In the industrial sector, it's used not only for generating electricity but also as a raw material for producing chemicals, fertilizers, and plastics.

Geological Context: Layering and Formation

The Earth’s crust is a complex amalgamation of layers, each created through specific geological processes. These layers, predominantly sedimentary in nature, are the primary hosts of hydrocarbon deposits.

Sandstone: As a sedimentary rock formed through the compression of sand over millions of years, sandstone plays a crucial role in the storage of hydrocarbons. Its inherent porosity makes it an ideal reservoir rock, where gas and oil can accumulate. The process begins when organic matter, deposited along with minerals, gets buried and undergoes chemical transformations due to heat and pressure, converting it into hydrocarbons. These then migrate upwards, getting trapped in the porous sandstone structures.
Gas-rich Shale: Shales are fine-grained sedimentary rocks that can sometimes contain vast amounts of hydrocarbons. Unlike sandstone, shales are typically source rocks, meaning they are the sites of original hydrocarbon formation. The organic matter trapped within them decomposes over time to produce natural gas. When this gas gets trapped within the shale itself, due to its low permeability, the result is gas-rich shale.

Classifying Natural Gas: Diversity in Deposits

Natural gas, though a generalized term, is found in varied settings, each distinct in its geology and formation history.

Conventional Nonassociated Gas: Found in individual pockets or reservoirs, this type of gas is not mixed with oil. Such accumulations are often the result of migration. Hydrocarbons, formed in source rocks, move upwards due to their buoyancy, and upon encountering impermeable barriers or traps, they accumulate.
Conventional Associated Gas: In certain geological settings, gas accumulates alongside oil. This coexistence often means that during oil extraction, natural gas is released as a byproduct. It's not uncommon for oil wells, especially in the earlier stages of production, to produce substantial amounts of natural gas.
Coalbed Methane: As its name implies, this gas is found within coal beds. Formed during the coalification process, it's primarily methane. The gas gets trapped within the coal’s porous structure, making extraction a unique process. Historically, this gas was considered a mining hazard but has now evolved into a valuable resource.
Tight Sand Gas: Certain gas deposits lie within sand formations that are not as porous as conventional reservoir rocks. These are termed "tight" due to the challenge they present in extraction. The gas in such deposits is usually trapped within compacted sandstone or limestone formations, requiring more sophisticated extraction techniques.

Natural Gas Value Chain

The journey of natural gas, from its source to households and industries, is a multifaceted process demanding precision and expertise. The graphic, provided by the U.S. Energy Information Administration, gives a clear and detailed breakdown of this journey, highlighting the interconnected systems at play. Each stage, from extraction to distribution, requires its own set of infrastructure and technological solutions, all specifically designed to guarantee safe, consistent, and effective delivery to various end-users across regions.

Production

Oil and Gas Well: The journey of natural gas begins at the oil and gas well. These wells are deep holes drilled into the earth, targeting underground reservoirs where natural gas and crude oil accumulate. The depiction of two different well structures suggests that natural gas can be sourced both from traditional vertical wells and more advanced directional or horizontal drilling techniques.
Separation: Once extracted, natural gas often accompanies a mixture of other hydrocarbons and impurities. Hence, a separation process is essential. Here, the gas is separated from crude oil, water, and other unwanted constituents. The separated crude oil ascends through the depicted pipeline, hinting at its separate processing route or direct transport for refining.
Vented and Flared: Some gases aren't immediately processed or transported. These might be non-commercial gases or excess pressures that need to be managed. Vented gases are released directly into the atmosphere, while flared gases are burned off. Flaring combusts the majority of the harmful hydrocarbons, converting them into water vapor and carbon dioxide.
Water: The water extracted alongside oil and gas, often referred to as 'produced water,' is either treated and reused, disposed of safely, or in some cases, re-injected into reservoirs.

Processing

Gas Processing Plant: Post extraction, the natural gas undergoes further refinement in a processing plant. Here, various compounds and non-methane hydrocarbons are removed. This ensures that the gas meets quality standards for commercial use.
Products Removed and Nonhydrocarbon Gases: By-products such as propane, butane, and ethane are separated and might be sold individually. Meanwhile, nonhydrocarbon gases, possibly sulfurous compounds or inert gases, are removed to prevent corrosion in pipelines and to enhance gas quality.
Returned to Field: Some gases, after processing, are returned to the field, possibly for reservoir pressure maintenance or because they are not commercially viable.
Vented and Flared (again): Similar to the production phase, certain gases from the processing plant might be vented or flared for operational safety or regulatory compliance.

Transmission

Compressor Station: Natural gas needs to be transported over vast distances from production facilities to consumers. Compressor stations play a pivotal role in this phase, ensuring gas maintains the requisite pressure to travel through pipelines. They are strategically placed along pipeline routes, re-pressurizing gas to keep it moving.
Main Line Sales: Post compression, the natural gas reaches main line sales points where it is sold and bought by natural gas companies. These companies might further distribute the gas to end consumers or use it for their industrial applications.
Odorant Addition: For safety reasons, an odorant is added to natural gas, which is naturally odorless. This ensures that in case of leaks, the distinct smell (often reminiscent of rotten eggs) alerts individuals.
Underground Storage Reservoir: To manage demand-supply fluctuations and ensure consistent supply, natural gas is stored underground, often in depleted oil or gas fields.
LNG Storage: For transport flexibility, especially over long distances where pipelines aren't feasible, natural gas is cooled and converted into Liquefied Natural Gas (LNG). These LNG storage facilities store gas in its liquid form until it's needed.

Distribution

Natural Gas Company: Once in the hands of natural gas companies, it's ready for distribution. These companies have the infrastructure and network to deliver gas to various consumer types.
Consumers: The end of the value chain sees natural gas reaching diverse consumers. Whether it's residential households using gas for heating and cooking, or commercial buildings and industries utilizing it for varied applications, natural gas finds multiple takers. The depiction of different structures, from homes to tall buildings, underscores its wide applicability.

North America's LNG Export Facilities

The map visualizes the geographical distribution of LNG export facilities in North America, detailing their statuses from 2016 to the forecasted year of 2027. Over the upcoming five years, North America is anticipated to witness a substantial growth in its LNG export capacity.

Existing and Under-Construction Capacities:

United States: Currently, the U.S. dominates with 11.4 Bcf/d of existing LNG export capacity. Over the projected period, this will experience an upswing by 9.7 Bcf/d, emanating from five significant projects: Golden Pass, Plaquemines, Corpus Christi Stage III, Rio Grande, and Port Arthur. Notably, the Golden Pass and Plaquemines projects are slated to commence exports in 2024.
Mexico: Three pivotal projects are in the pipeline, cumulatively accounting for an export capacity of 1.1 Bcf/d. These include:
- Fast LNG Altamira: Comprising three units with a combined capacity of 0.54 Bcf/d, with offshore and onshore installations at the Altamira LNG regasification terminal.
- Fast LNG Lakach: Positioned offshore of Veracruz, it will have an export capacity of 0.18 Bcf/d.
- Energia Costa Azul: Situated in Baja California, the two-phase project will offer 0.4 Bcf/d in its first phase and a proposed 1.6 Bcf/d in the subsequent phase.

Canada: British Columbia will host two substantial projects, namely LNG Canada and Woodfibre LNG, contributing 1.8 Bcf/d and 0.3 Bcf/d respectively to the country's export capacity.By 2027's end, the aggregate addition in LNG export capacity across North America is estimated to be a whopping 12.9 Bcf/d, stemming from a sum of ten new ventures spread across these three nations.

Projects on the Horizon:

Mexico: Multiple proposed projects for the west coast, such as Saguaro Energia LNG, Salina Cruz FLNG, and Vista Pacifico LNG, could add over 2.7 Bcf/d. Notably, these initiatives will predominantly leverage affordable natural gas from the U.S., targeting the Asian markets. However, the final investment decisions for these undertakings are still pending.
Canada: The National Energy Board (NEB) has authorized an array of 18 LNG export projects, which, if realized, would contribute an astounding 29 Bcf/d.

Page updated

Google Sites

Report abuse