Novel high-efficiency crude oil electric dehydration and desalination method and equipment

Abstract

The invention discloses a novel high-efficiency crude oil electric dehydration and desalination method and novel high-efficiency crude oil electric dehydration and desalination equipment, which can be used for dehydrating and desalinating crude oil emulsion in oil refineries. The processing equipment mainly comprises an inlet component, a tank and an electrostatic precoalescer; when a high-voltage explosion-proof transformer outside the device applies high-voltage alternating current to the crude oil emulsion in a corrugated hollow tube through metal electrode plates by a high-voltage insulating wire, a non-uniform alternating current field is produced between the electrode plates to cause dielectrophoresis coalescence of dispersed phase water particles; the flow state of the crude oil emulsion in the hollow tube is turbulent flow, and the turbulent flow increases the collision probability of the dispersed phase water particles in the crude oil emulsion and obviously shortens hydraulic retention time; and a flowing passage in the electrostatic precoalescer can be designed to be corrugated circular or wavelike quasi-rectangular. By using the method and the equipment, the dispersed phase water particles subjected to electrostatic precoalescence can obviously reduce subsequent gravity settling time and improve the processing efficiency; and after the crude oil emulsion enters the tank from the inlet component at the left end, the crude oil emulsion flows along the horizontal direction and can reduce the power consumption of an inlet.

Description

technical field [0001] The invention belongs to the technical field of electric dehydration and desalination of crude oil, and relates to a novel high-efficiency electric dehydration and desalination method and equipment for crude oil, which are suitable for dehydration and desalination of small water particles in dispersed phases in crude oil emulsions of refineries and heavy oil emulsions. Background technique [0002] For a long time, there are two main types of electric dehydration (desalter) devices used in oil fields and refineries at home and abroad: one uses horizontal horizontal electrodes, and the other uses horizontal vertical suspension electrodes. In these two forms of electric dehydration (desalination) devices, the electrodes are arranged on the upper part of the tank. In a conventional electric dehydration (desalter) device, the water-in-oil (W / O) type crude oil emulsion enters from the bottom of the tank, and the overall flow trend is from bottom to top. La...

AI Technical Summary

Problems solved by technology

Its disadvantages are: before the treated crude oil emulsion enters the subsequent sedimentation and separation equipment, it should avoid breaking the larger dispersed phase water particles due to severe shearing; at the same time, it can emulsify W / O crude oil The adaptability of gas content and water content in the liquid is low

Its disadvantage is that the structure is relatively complex and requires a high level of processing and manufacturing; when the crude oil emulsion flows through a circular or quasi-rectangular flow channel, the suspended solid particles contained in the crude oil emulsion settle down based on gravity, covering the Electrode surface, easy to cause electrode short circuit

Its disadvantage is that before the coalesced crude oil emulsion enters the subsequent sedimentation and separation equipment, the larger dispersed phase water particles may be broken again due to the severe shearing action of elbows, valves, etc. in the pipeline ; Under large processing capacity, multiple single-tube vertical structures need to be connected in parallel, and the overall footprint is large

The disadvantage is that it is only suitable for electrostatic pre-coalescence of dispersed phase water particles in low water content crude oil emulsions, and has low adaptability to water content in W / O crude oil emulsions; it is installed inside a conventional gravity separator for use Its structure is relatively complex, and it requires a high level of processing and manufacturing; when the crude oil emulsion flows through the corrugated plate electrode assembly, the suspended solid particles contained in the crude oil emulsion settle down and cover the surface of the electrode, which is likely to cause short circuit of the electrode

But its shortcoming is that it has low adaptability to the gas content and water content in W / O crude oil emulsion; only the dipole coalescence or oscillation coalescence demulsification mechanism is used, and the dielectrophoresis phenomenon is not fully realized. The important value of electrostatic pre-coalescence

Many domestic researchers have conducted a lot of experimental research on the electrostatic coalescence and demulsification mechanism of W / O crude oil emulsion, and the field application of compact electrostatic pre-coalescence equipment is still in its infancy.

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