What is Static Equipment? List with Details in Oil and Gas Industry [PDF]

Static equipment in the oil and gas industry plays a critical role in various processes, serving as the backbone for storage, separation, heat exchange, and other essential functions. These pieces of equipment are stationary, meaning they do not typically have moving parts. In this comprehensive explanation, we will delve into the different types of static equipment used in the oil and gas industry, their functions, key features, and the significance of proper design, maintenance, and inspection.

1. Pressure Vessels:

Pressure vessels are one of the most vital types of static equipment in the oil and gas industry. They are containers designed to store and contain pressurized fluids or gases. These vessels come in various shapes and sizes, depending on their intended application.

Functions:
Pressure vessels serve multiple functions in the industry, including:

1. Storage: They are used to store hydrocarbons, chemicals, and other fluids under pressure or at elevated temperatures. For example, crude oil storage tanks are a common type of pressure vessel.
2. Reaction: Pressure vessels are employed in chemical processes where reactants need to be held under pressure to facilitate specific reactions. Reactors in petrochemical plants are an example of this application.
3. Heat Exchange: Some pressure vessels, such as heat exchangers, are designed to transfer heat between two fluids while keeping them separate. This is crucial in various refining and cooling processes.

Examples:

• Tanks: These are large cylindrical or spherical vessels used for bulk storage of crude oil, refined products, chemicals, or gases. They come in various designs, such as fixed-roof tanks, floating-roof tanks, and spherical tanks.
• Reactors: These vessels are specifically designed for chemical reactions. They often have agitators to ensure proper mixing of reactants.
• Heat Exchangers: Heat exchangers are pressure vessels used to exchange heat between two fluids without them coming into direct contact. Shell and tube heat exchangers are commonly used in the industry.

Pressure vessels must be designed to handle the specific pressure, temperature, and material properties associated with the substances they will contain. They are subject to rigorous design codes and standards to ensure safety and reliability. Proper maintenance and inspection are essential to prevent accidents and ensure compliance with regulatory requirements.

2. Heat Exchangers:

Heat exchangers are static equipment designed to transfer heat between two fluids without allowing them to mix. They are used extensively in the oil and gas industry to control temperatures in various processes.

Functions:
Heat exchangers play a crucial role in several processes, including:

1. Cooling: They remove excess heat generated during refining and other processes. Cooling towers and air-cooled heat exchangers are common in this application.
2. Heating: Heat exchangers can heat fluids, such as crude oil, before they enter processing units to improve their flow properties and reduce viscosity.
3. Condensation: In condensation processes, heat exchangers are used to convert vapor into a liquid state. This is essential in natural gas processing.

Examples:

• Shell and Tube Heat Exchangers: These consist of a cylindrical shell with a bundle of tubes inside. One fluid flows through the tubes, and the other flows around the tubes within the shell. They are widely used for various applications, including heating, cooling, and condensation.
• Plate Heat Exchangers: These are compact and efficient heat exchangers made up of multiple thin plates with gaskets. They are commonly used when space is limited.

Heat exchangers must be designed to handle the specific temperatures and flow rates of the fluids involved. Proper maintenance, including regular cleaning and inspection of heat exchanger tubes and fins, is vital to ensure efficient heat transfer and prevent fouling.

3. Storage Tanks:

Storage tanks are static equipment designed to hold and store crude oil, refined products, chemicals, or other liquids. They are a fundamental component of the oil and gas industry’s infrastructure.

Functions:
Storage tanks serve the following functions:

1. Inventory Management: They provide a means to store and manage inventories of crude oil, gasoline, diesel, and other liquid products.
2. Blending: In some cases, storage tanks are used for blending different grades of crude oil or refined products to achieve desired specifications.
3. Buffering: They act as buffers between different stages of processing to ensure a continuous supply of feedstock to downstream units.

Examples:

• Crude Oil Storage Tanks: These tanks are typically large and can hold millions of barrels of crude oil. They come in various types, including fixed-roof tanks, floating-roof tanks, and underground storage tanks.
• Product Storage Tanks: These tanks store refined products like gasoline, diesel, and jet fuel. They are usually smaller and have floating roofs to minimize vapor emissions.

Proper design and maintenance of storage tanks are essential to prevent leaks, spills, and environmental damage. Inspection methods such as ultrasonic testing are used to assess the integrity of tank shells and bottoms.

4. Columns and Towers:

Columns and towers are static equipment used in the oil and gas industry for separation processes based on differences in boiling points. They are a critical component of refining and petrochemical plants.

Functions:
Columns and towers serve the following functions:

1. Distillation: They separate crude oil into its various components, including gasoline, diesel, kerosene, and heavier products, based on their boiling points.
2. Absorption: In absorption towers, they remove specific components, such as sulfur or carbon dioxide, from gas streams by dissolving them into a liquid absorbent.

Examples:

• Distillation Columns: These are tall, vertical towers with multiple trays or packing materials. As vapor rises through the column, it condenses on trays or packing, and the separated liquid is collected at different levels based on its boiling point.
• Absorption Towers: In these towers, a gas stream is brought into contact with a liquid absorbent to remove specific components. For example, amine towers are used to remove hydrogen sulfide from natural gas.

Columns and towers are designed to operate under specific temperature and pressure conditions to achieve the desired separation efficiency. Regular maintenance and inspection are essential to ensure the packing or trays are functioning correctly and to identify any corrosion or fouling issues.

5. Fired Heaters:

Fired heaters, also known as process heaters or furnaces, are static equipment that generates heat by burning fuels. They are commonly used in various oil and gas processes, including refining and petrochemical production.

Functions:
Fired heaters are primarily used for heating processes and serve the following functions:

1. Cracking: In the catalytic cracking process, fired heaters are used to heat feedstocks to break down large hydrocarbon molecules into smaller ones.
2. Reforming: In reforming processes, they provide the heat required to initiate chemical reactions that convert low-octane hydrocarbons into high-octane gasoline components.
3. Distillation: Some refinery processes, like vacuum distillation, require heating to separate heavy fractions from crude oil.

Examples:

• Process Heaters: These heaters are used for general heating purposes in various refining and petrochemical processes. They are typically fired with natural gas, refinery fuel gas, or other fuels.
• Cracking Furnaces: These are specialized heaters used in fluid catalytic cracking (FCC) units to heat the catalyst and hydrocarbon feed.

Fired heaters are designed with safety features to prevent explosions and ensure the efficient

combustion of fuels. Regular maintenance, including cleaning burners and checking refractory materials, is crucial to maintain their performance.

6. Separators:

Separators are static equipment used to separate mixtures into distinct phases, such as separating oil from water or gas from liquid. They are employed in various stages of the oil and gas production process.

Functions:
Separators perform the following functions:

1. Oil-Water Separation: In the production of crude oil, separators are used to separate water from the oil-water mixture that comes out of the well. This is crucial to ensure the quality of the produced oil.
2. Gas-Liquid Separation: In natural gas processing, separators remove liquid hydrocarbons and water from the gas stream.
3. Three-Phase Separation: Some separators are designed to separate oil, gas, and water simultaneously.

Examples:

• Two-Phase Separators: These separate a gas phase from a liquid phase (usually oil or water). They typically have an inlet diverter and gravity settling section.
• Three-Phase Separators: These are designed to separate gas, oil, and water. They have more complex internals, including baffles and weirs.

Proper design and operation of separators are essential for maintaining the quality of oil and gas products and preventing equipment damage. Maintenance includes cleaning and inspecting internals, checking level controls, and monitoring for corrosion.

7. Pressure Relief Devices:

Pressure relief devices are critical safety components in the oil and gas industry. They are designed to prevent overpressure situations in equipment by releasing excess fluid or gas to a safe location.

Functions:
Pressure relief devices serve the following functions:

1. Safety: They protect equipment from overpressure, which can lead to catastrophic failures such as explosions or ruptures.
2. Environmental Protection: They prevent the release of hazardous materials into the environment in the event of an overpressure situation.
3. Asset Protection: By relieving excess pressure, they safeguard expensive equipment from damage.

Examples:

• Pressure Relief Valves (PRVs): These are the most common type of pressure relief device. They are designed to open and release fluid when the pressure in the vessel exceeds a preset limit. PRVs are typically used on pressure vessels and pipelines.
• Rupture Disks: These are non-reclosing pressure relief devices that rupture at a predetermined pressure. They are often used in applications where rapid relief is required.

Pressure relief devices must be properly sized, installed, and maintained to ensure they function as intended. Regular testing and inspection are essential to verify their performance.

8. Cooling Towers:

Cooling towers are static equipment used to remove excess heat from industrial processes by dissipating it into the atmosphere. They are commonly employed in refineries and petrochemical plants.

Functions:
Cooling towers serve the following functions:

1. Heat Dissipation: They dissipate heat generated during processes by transferring it to the atmosphere through the evaporation of water.
2. Temperature Control: Cooling towers help maintain the temperature of circulating process fluids within desired limits.

Examples:

• Mechanical Draft Cooling Towers: These towers use mechanical fans to induce air movement through the tower. They are often used in large industrial facilities.
• Natural Draft Cooling Towers: Natural draft towers rely on the buoyancy of hot air to draw air through the tower. They are typically used in power plants and large industrial complexes.

Cooling towers require regular maintenance to ensure optimal performance. This includes cleaning of cooling coils, monitoring water treatment systems, and inspecting fans and structural components.

9. Filtration Equipment:

Filtration equipment is used to remove solids or impurities from fluids or gases in the oil and gas industry. It plays a vital role in maintaining the quality of various products and protecting downstream equipment.

Functions:
Filtration equipment serves the following functions:

1. Particle Removal: Filtration removes solid particles from liquids or gases to prevent fouling of equipment and ensure product quality.
2. Contaminant Removal: It removes contaminants such as oil, sand, and corrosion products from process streams.

Examples:

• Filter Vessels: These vessels contain filter cartridges or bags that trap solid particles as fluid flows through them. They are used for various applications, including water filtration and fuel polishing.
• Coalescers: Coalescers are designed to remove small liquid droplets from gas streams. They are commonly used in natural gas processing to remove entrained liquids.

Filtration equipment requires regular replacement of filter elements and cartridges to maintain efficiency. Differential pressure measurements are often used to indicate when filters need to be changed.

10. Ducting and Piping:

Ducting and piping systems are essential for transporting fluids, gases, or solids within an oil and gas facility. They provide the infrastructure for the movement of materials between various units and processes.

Functions:
Ducting and piping serve the following functions:

1. Material Transport: They transport raw materials, intermediate products, and finished products between different processing units.
2. Fluid Control: Piping systems are used to control the flow of fluids within a facility, ensuring that they reach their intended destinations.

Examples:

• Pipes: Pipes are used to transport liquids and gases. They come in various materials, sizes, and configurations to accommodate different requirements.
• Pipe Fittings: Fittings such as valves, elbows, and tees are used to control and direct the flow of fluids within the piping system.

Regular inspection and maintenance of piping systems are crucial to identify and address issues such as corrosion, leaks, and blockages. Non-destructive testing methods like ultrasonic testing are used to assess the integrity of pipes.

11. Static Mixers:

Static mixers are static equipment designed to mix or blend fluids without the need for moving parts or external energy sources. They find applications in processes where thorough mixing is essential.

Functions:
Static mixers serve the following functions:

1. Homogenization: They ensure uniform mixing of different components in a fluid stream.
2. Chemical Reaction: In some applications, static mixers are used to facilitate chemical reactions by promoting contact between reactants.

Examples:

• In-line Mixers: These are installed within pipelines and use a combination of stationary blades or elements to mix fluids as they flow through.
• Motionless Mixers: These mixers consist of stationary elements or channels that create turbulence to promote mixing.

Static mixers are low-maintenance equipment, but their performance should be periodically checked to ensure efficient mixing.

12. Flare Stack and Knock Out Drum

A flare stack, also known as a flare tower or flare stack system, is a tall structure equipped with burners that safely and efficiently burn off unwanted or excess gases released during various industrial processes, especially in the oil and gas industry. Flare stacks are a crucial safety measure to prevent the release of potentially hazardous gases into the atmosphere.

Flare & Knock Out Drum:

A Flare & Knock Out Drum is a combination of two essential components within an oil and gas facility: a flare drum and a knockout drum. These components work together to separate and manage the flow of gases and liquids, ensuring safe and efficient operation.

13. Jet Ejector and Scrubber:

A jet ejector, also known as a jet pump or eductor, is a device that utilizes a high-pressure fluid (usually a liquid or gas) to entrain and transport another fluid or gas from a lower pressure region to a higher pressure region. Jet ejectors operate based on the principle of fluid dynamics, using the kinetic energy of the motive fluid to create a vacuum and induce the flow of the suction fluid or gas.

A scrubber refers to a pollution control device designed to remove pollutants, particulates, or gases from exhaust or process gas streams. Scrubbers are crucial for environmental compliance and maintaining air quality standards, especially in industries where emissions can be harmful or pose health and safety risks.

In conclusion, static equipment is a fundamental component of the oil and gas industry, providing critical functions such as storage, separation, heat exchange, and fluid transport. These stationary components are designed to operate under specific conditions, and their proper design, maintenance, and inspection are essential to ensure safety, efficiency, and compliance with industry standards and regulations. Neglecting the maintenance and inspection of static equipment can lead to safety hazards, environmental risks, and operational inefficiencies, making their proper care a top priority in the industry.