Storage and Transportation
Underground storage facilities are the most common type of natural gas storage in the midstream sector. These facilities use depleted natural gas reservoirs, aquifers, or salt caverns to store natural gas. The storage sites are typically located near the natural gas pipelines that transport the gas from production fields to end-users. The natural gas is injected into the storage facility during low demand and withdrawn during high demand.
2. Aquifers: Aquifers are underground rock formations that contain water. Some aquifers can also be used for natural gas storage. Natural gas is injected into the aquifer and is stored in the pore spaces between the rock particles. Water is displaced and usually pumped to the surface when gas is withdrawn from the aquifer. Aquifers are typically used for seasonal storage of natural gas.
3. Salt caverns: Salt caverns are underground caverns formed by the dissolution of salt deposits. These caverns can be repurposed for natural gas storage by injecting gas into the cavern and using the salt as a seal to prevent leakage. Salt caverns have high deliverability rates, meaning they can rapidly inject or withdraw gas in large volumes. They are often used for peak demand storage or emergency supply.
Above-ground storage facilities are used for storing natural gas in tanks, which can be located above or below ground. These facilities are typically used for smaller volumes of natural gas and are often found in areas with more than underground storage.
There are four types of above-ground storage facilities for natural gas:
1. Spheres: Spherical tanks are large, spherical containers made of steel that store natural gas. They are usually located in industrial or urban areas and are designed to keep large gas volumes. Spheres have a relatively small footprint and can withstand high pressure, making them suitable for use in urban areas.
2. Cylindrical tanks: Cylindrical tanks are vertical, cylindrical containers made of steel or concrete. They are used to store smaller volumes of natural gas than spheres and are often used in rural areas or for individual consumers.
3. Bullet tanks: Bullet tanks are horizontal, cylindrical containers made of steel. They are used to store smaller volumes of natural gas than cylindrical tanks and are often used in rural areas or for individual consumers.
4. LNG storage tanks: LNG (liquefied natural gas) storage tanks store natural gas in liquid form. The natural gas is cooled to a shallow temperature, causing it to condense into a liquid. LNG storage tanks are typically large, insulated containers made of steel or concrete.
The choice of an above-ground storage facility depends on factors such as the volume of gas to be stored, the location of the storage facility, and the regulatory environment. Proper maintenance and safety protocols are critical to ensure the safe and efficient operation of the facility, regardless of the type of above-ground storage facility used.
The natural gas storage infrastructure in the midstream sector includes pipelines, compressors, injection and withdrawal wells, and metering and monitoring equipment. These facilities are designed to ensure the safe and efficient storage and transport of natural gas from production fields to end users.
The natural gas storage infrastructure in the midstream sector is critical in ensuring a reliable and affordable supply of natural gas to end users. By storing natural gas during times of low demand and withdrawing it during times of high need, these facilities help to balance supply and demand and maintain a stable price for natural gas.
After natural gas is stored in midstream facilities, it needs to be transported to end-users such as homes, businesses, and industrial facilities. Natural gas transportation is typically done through pipelines, which are the most efficient and cost-effective means of transport.
Natural gas pipelines can be thousands of miles long, and they connect production areas to storage facilities and end-users across different regions and countries. These pipelines are made of steel, plastic, or composite materials and are designed to withstand high pressure and extreme weather conditions. Natural gas is transported through pipelines by compressing it at intervals along the pipeline. The compressors increase the gas pressure, pushing it through the pipeline. Monitoring and control systems are in place to regulate the gas's pressure, temperature, and flow rate to maintain the pressure and flow of natural gas.
Natural gas may be transported in a liquefied form (LNG) using specialized ships or trucks. LNG is produced by cooling natural gas to a shallow temperature, which causes it to condense into a liquid state. LNG is less dense than natural gas, making transporting over long distances more efficient. Regardless of the method used, natural gas transportation requires careful planning, monitoring, and management to ensure the safe and efficient delivery of gas to its end users.
