Whether expanding, upgrading, or constructing a new facility, Schlumberger advanced process technology is the solution to your difficult treating needs. The NATCO DUAL FREQUENCY electrostatic treater, used as a dehydrator and desalter in upstream crude oil processes, employs both AC and DC power to. Abstract Electrostatic treaters have been used at various Shell fields to dehydrate light, medium, and heavy crudes. The performance and operating envelope of.
|Published (Last):||13 November 2012|
|PDF File Size:||2.91 Mb|
|ePub File Size:||1.88 Mb|
|Price:||Free* [*Free Regsitration Required]|
Free gas is released as emulsion strikes the hood or down-comer and rises to the top of the inlet section.
If fluid temper-ature gets below this level, the grids will not have the proper treating effect on the emulsion. Alternating current on the lower electrical grid GRIDS causes it to reverse polarity change from positive to negative times per second or 60 cycles per second.
Emulsion enters the treater, splashes over the U-shaped hood or downcomer and flows down-ward to the bottom of the vessel. Development of Design and Operating Guidelines. Ina pilot-scale Chem-Electric Treater PSCET was built 1 to address the operating problems encountered in dehydrating heavy crudes, 2 to investigate electrostatic dehydration of light and medium crude, and 3 to provide a broad data base for various crudes.
Electrostatic Treaters Process
It then travels upward across the firetubes and spills over a weir into the surge section. Figure illustrates a typical design of a horizontal electrostatic treater. Advanced search Show search help. The lower grid is not grounded and receives the electrical output from the transformer.
Chemicals are usually injected into the emulsion upstream from the treater. Treaters Water Separator Droplet Size. Some treaters have a heat exchanger installed on the inlet line. Free water falls to the water section of the vessel and the emulsion rises to the coalescing section. The flow path in an electrostatic treater is the same as a horizontal treater.
There are several reasons why a higher pressure is maintained in the first two sections. However, for normal crude treating, where 0. Centrifugal force creates a vortex and accentuates the separation effect. Adequate retention time is provided to ensure that the water settles and that the gas breaks out of the oil. The objectives of the pilot-scale investigations were to determine sizing criteria for electrostatic treaters, provide operating guidelines, and identify the tolerance of these treaters to solids and gas upsets.
Electrostatic treating begins below the lower grid and is completed between the upper and lower grids where water droplets coalesce and settle out. The upper grid is grounded to the vessel shell and is adjustable so that the electrostatic field can be regulated to meet varying coalescing requirements.
Electrostatic Treaters Process | Oil and Gas Separator
Proceedings of an international conference Subsea Controls and Data Acquisition ‘ A circuit breaker, located between the power source and the transformer, protects the transformer from electrical power failures.
The transformer is the heart of the electrical system. If the burners remain on, the treater may overheat and be damaged, the lighter ends of the oil may be cooked off changing gravity, and oil volume will be decreased resulting in lost revenue. The firetubes heat the emulsion which aids in separation of oil and water.
The inlet and surge sections are held at a slightly higher pressure than the treating section. Electrostatic treaters have been used at various Shell fields to dehydrate light, medium, and heavy crudes.
Khatib Shell Oil Co. The use of electrostatic treaters at North Midway Sunset leases, California, showed that electrostatic treaters worked but needed a lot of attention to light crude addition, emulsion-breaking chemicals, gas breakout, solids accumulation on the interface, the applied field strength, and the conductivity of the crude.
The oil-water emulsion then flows into the heating section of the treater. Since most emulsions being treated contain a certain amount of sludge and solids, the firetubes should be checked for corrosion, rust and accumulation of scale.
The two grids are suspended one above the other in the treating section.
Therefore, the treating process has already begun by the time the emulsion reaches the treater. If it hits the firetube directly, a hot spot will form and premature firetube failure will occur.
The type of valves and controls used varies depending on the treater construction. Rock Mechanics Symposium and 5th U. Since electrostatic treaters operate under pressure, they should be equipped with pressure relief devices that have enough capacity to protect the treater if pressure increases.
Since coalescence of droplets in an electric field is so dependent on the characteristics of the particular emulsion to be treated, it eectrostatic unlikely that a general relationship of water droplet size to use in the settling equations can be developed. This action lifts the diaphragm and allows water to flow through the dump valve.
Some electrostatic treaters are designed to allow water in the inlet section to join water in the treating seciion before being removed from the treater.
Most electrostatic treaters have a reac-tance type transformer which has a reactor to protect the transformer from power electrostwtic and high voltage dispersion. The lowest possible temperature to adequately treat the emulsion should be used. The maximum working pressure for a treater can be found on the manufacturer’s information plate attached to the treater. Field experience tends to indicate that electrostatic treaters are efficient at reducing water content in the crude below the 0.
Proceedings of electrostatci international conference Oceanology: A major purpose of the surge section is to keep the treating section “fluid-packed. This causes the water droplets to move around rapidly and collide with each other with enough force to break the thin film surrounding each droplet.