What are the Advantages Combined Electric Field Electrodesalting Technology?

In modern crude oil dehydration and desalting processes, stable operation under high water-cut and strong emulsification conditions has become a critical challenge for offshore and onshore oilfield production systems. Conventional electrostatic dehydration equipment often faces issues such as unstable electric field establishment, short circuits, excessive operating current, and increased energy consumption when treating crude oil with elevated water content. To address these operational limitations, our company has developed an advanced electrostatic coalescence composite electric field technology based on extensive field application experience, continuous technical optimization, and patented electrode design.

By combining AC/DC vertical electrode plates with intelligent pulsed insulated horizontal electrodes, this technology significantly improves electric field distribution, enhances water droplet coalescence efficiency, and maintains stable dehydration performance even under high water-content operating conditions. The system has demonstrated excellent adaptability, operational stability, and energy-saving performance in practical industrial applications, providing a reliable technical solution for efficient crude oil dehydration and desalting processes.

Advantages of Combined Electric Field Electrodesalting Technology

I.The use of AC/DC vertical electrode plates + intelligent pulsed horizontal insulated electrodes forms a composite electric field, expanding the radiation area of the electric field. The weak electric field generated by the lower insulated electrodes can remove larger water droplets, providing favorable conditions for crude oil to enter the medium and strong electric fields in the upper section. This reduces the conductivity of the upper crude oil, preventing short circuits, high operating currents, and excessive energy consumption when the oil enters the strong electric field area of the vertical electrode plates, thereby enhancing the stability of the system.

II.Additionally, if the water content in the oil increases later, even exceeding 35% (normally, an electric field cannot be established beyond 30%), the lower insulated electrodes can still establish an electric field normally, removing a significant amount of water droplets and providing stable conditions for the upper vertical exposed electric field, ensuring post-treatment indicators are met.

III. Technical Principle of Electrostatic Coalescence Composite Electric Field:

Electro-dehydration/desalting utilizes the action of an electrostatic field to break the crude oil emulsion, causing water droplets to attract and coalesce with each other, ultimately settling and separating completely from the crude oil. The electrostatic coalescence composite electric field technology consists of upper and lower sections of electrodes combined: the upper section features conventional metal vertical electrode plates, while the lower section employs horizontal electrode plates made of insulated materials, which are patented by our company. 

The crude oil emulsion enters the electro-desalting/dehydration vessel in a bottom-in-top-out flow pattern. It first passes through the electrostatic field of the lower insulated electrodes to remove larger water droplets. The crude oil containing smaller water droplets then enters the upper vertical electrode plates for further separation. Since the lower insulated electrodes can establish an electrostatic field in high water content regions and remove larger water droplets, this prevents situations where larger water droplets entering the upper electric field could cause short circuits.

IV. The electrostatic coalescence technology was awarded the First Prize for Scientific and Technological Progress in 2021 and the Outstanding Innovation Achievement Award in 2023.This technology has obtained 2 invention patents and 10 utility model patents.

the First Prize for Scientific and Technological Progress

Applicants: CNOOC Research Institute Co., Ltd.

Luoyang Zhengyuan Petrochemical Co., Ltd.

Project Name : Efficient Dehydration Technology of Electrostatic Coalescing Crude Oil

Conclusion

With the continuous development of high water-cut oilfield production, the demand for efficient, stable, and energy-saving crude oil dehydration technology is increasing across the petroleum industry. The electrostatic coalescence composite electric field technology developed by our company combines patented insulated electrode structures with optimized electric field distribution to improve dehydration efficiency and operational reliability under complex working conditions.

Through practical engineering applications, patented innovation achievements, and industry-recognized awards, this technology has demonstrated strong technical feasibility and industrial value in the treatment of highly emulsified crude oil systems. By effectively reducing short-circuit risks, lowering energy consumption, and maintaining stable electric field performance even at high water content levels, the system provides a dependable solution for modern crude oil electro-dehydration and desalting operations.