Oil & Gas Processing Applications

 
 
Drilling Fluid Tanks

Application

A cement slurry prepared on location (or trucked in) cements the well casing. Drilling fluids lubricate the drill bit, remove cuttings, prevent open wellbore collapse and maintain hydrostatic equilibrium for blowout protection. Water- and oil-based "muds" are used. Dispersants, flocculants, surfactants and rust inhibitors may be added to the drilling fluid.

Challenges

Drilling fluids are typically stored in a series of partitioned, rectangular steel tanks. The tank fluid volume should be continuously monitored since level variations may indicate a pending blowout. Tank conditions include agitated media, suspended solids and media that will coat floats, displacers and probes.

Suitable Products

Atlas™ Magnetic Level Indicator

Eclipse™ Model 705 Guided Wave Radar Transmitter

Eclipse™ Model 706 Guided Wave Radar Transmitter

Water Processing

Application

Produced water, wash-down water or rainwater (collected offshore) require treatment whether they're re-used for reservoir flooding or simply disposed of. Water collected from process operations contains hydrocarbon concentrations too high for safe discharge. Suspended hydrocarbon droplets in water also hinders well-injection.

Challenges

Treatment equipment is similar to three-phase separators except that water is the main product. Level control is found on skim tanks, precipitators, coalescers, flotation units, and collection tanks and sumps. Interface level measurement is essential for proper draining of clean water and removal of the residual oil.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Crude Stabilization

Application

By removing dissolved gases and hydrogen sulfide, crude stabilization and sweetening processes diminish safety and corrosion problems. Gases are removed by a stabilizer. Sweetening employs stabilization or vaporization processes along with a gas or steam-based stripping agent.

Challenges

Removing dissolved gases by stabilization requires level control in the reboiler unit. Sweetening by stage vaporization and trayed stabilization require level control in a series of staged separators. Sweetening by reboiled trayed stabilization requires additional level control in a reboiler.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Application

Salt in the crude stream presents serious corrosion and scaling problems and must be removed. Salt is dissolved within the remnant brine of the crude oil. Desalting removes both salt and the residual free water. Though the refinery is the most economical place for desalting, pipeline requirements often necessitate field desalting.

Challenges

Level instrumentation is integral to single and two-stage desalting systems, multiple orifice plate mixers, and the settler tank of a chemical desalter. Interface level control keeps free water from hitting the desalter electrodes and prevents expensive damage. The Interface level should be kept constant otherwise electrical field changes will disturb electrical coalescence.

Suitable Products

 
 
Crude Dehydration

Application

Not all water is removed from crude oil during the first stage of gravity separation. Separated crude may contain up to 1520water which exists in an emulsified form that is difficult for a separator to remove. The oil and water emulsion must be broken down so that the water can be removed before the crude is shipped. Deemulsification processes are accomplished using chemical agents and heat.

Challenges

Level control is found on two-phase and three-phase water knock out drums, heater treaters and chemelectric dehydrators. Interface measurement is critical in dehydration as it keeps the water-emulsified oil from flowing over the separator weir.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Sour Gas Treatment

Application

Pipeline specifications require removal of the harmful acid gases carbon dioxide (CO2) and hydrogen sulfide (H2S). 2S is highly toxic and corrosive to carbon steels. CO2 is also corrosive and reduces a gas's BTU value. Gas sweetening processes remove these acid gases and make natural gas marketable and suitable for transportation.

Challenges

Amine treatment removes acid gases through absorption and chemical reaction. Each of the four common amines (MEA, DEA, DGA and MDEA) offer distinct advantages in specific applications. Level control applications include reactors, separators, absorbers, scrubbers and flash tanks.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Vapor Recovery Unit


Application

If allowed to escape into the atmosphere, hydrocarbon vapors diminish income through loss of hydrocarbon volume and create fire hazards and pollution problems. A Vapor Recovery Unit (VRU) collects vapors from storage and loading facilities, reliquefies the vapors and returns the liquid hydrocarbons back to storage. Methods to recover vapors include absorption, condensation, adsorption and simple cooling.

Challenges

A VRU is a simple, economical process unit that provides EPA compliance and improves operating economies by capturing up to 9520 of fugitive emissions. Critical to the VRU is the flash drum where vapors are reliquefied. Liquid level control of the flash drum is essential.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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NGL Recovery

Application

Separating the hydrocarbons and fluids from pure natural gas produces pipeline quality dry natural gas. The two principle techniques for removing Natural Gas Liquids (NGLs) are the absorption and the cryogenic expander method. The absorption method is very similar to that of dehydration except that an absorbing oil is used instead of glycol. Once NGLs have been removed from the natural gas stream, they must be separated out, or fractionated.

Challenges

Level control in the absorption method is typically found in flash drums, separation towers and reflux systems. Level control in the cryogenic method is applied to the separator and dehydrator.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Gas Dehydration

Application

Natural gas dehydration removes hydrates which can grow as crystals and plug lines and retard the flow of gaseous hydrocarbon streams. Dehydration also reduces corrosion, eliminates foaming, and prevents problems with catalysts downstream. Natural gas is dehydrated according to the customer's specifications for maximum water content.

Challenges

The most common dehydration method is the absorption of water vapor in the liquid desiccant Triethylene Glycol (TEG). The withdrawal of the water rich glycol from the bottom of the absorber is facilitated by a level control. High and low level shut down can be applied to the reboiler, surge tank and flash separator.

Suitable Products

Atlas™ Magnetic Level Indicator

Aurora® Magnetic Level Indicator

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Chemical Injection Skids

Application

Chemical agents employed in field processing include drilling fluid additives, methanol injection for reservoir stimulation, glycol injection for hydrate inhibition, produced water treatment chemicals, foam and corrosion inhibitors, de-emulsifiers, desalting chemicals and drag reduction agents (DRAs). Chemicals are frequently administered by way of chemical injection skids.

Challenges

Level monitoring controls chemical inventory and determines when the tanks require filling. Though the precise measurement often comes from chemical metering pumps, it is important for the tanks not to run out or overflow.

Suitable Products

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Well Stream Separation

Application

The first step in processing the well stream is to separate the crude oil, natural gas and water phases into separate streams. Oil and gas fields utilize two-phase gas/oil and gas/condensate separators as well as three-phase gas/oil/water separators. Units are classified according to horizontal or vertical configuration, operating pressure, turbulent or laminar flow, and test or production separation.

Challenges

Interface level measurement will actuate a valve to adjust vessel level. An emulsion layer along the oil/water interface can contaminate the oil with water or the water with oil. Foaming along the gas/liquid interface, if entrained, can cause liquid carryover or gas blow-by.

Suitable Products

Jupiter® Magnetostrictive Level Transmitter

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