Demulsifiers for Crude Oil Desalting
In crude oil extraction, the multiphase fluid formed by oil, natural gas and a large amount of brine is subjected to strong shear at the perforation layer, downhole pump and wellhead, resulting in aggravated emulsification. Natural emulsifiers and solid impurities in crude oil further stabilize the emulsification interface, making it difficult to separate the emulsion. Most of the crude oil initially extracted is oil-in-water emulsion, which needs to be converted into a water continuous phase to achieve effective oil-water separation. However, gravity separation efficiency is low, especially when the relative density difference between hydrocarbons and water is small. In order to improve the demulsification effect, natural gas in the fluid is often removed first, which can be achieved by heating oil or emulsion, which can not only promote static coagulation of emulsion, but also melt wax, reduce crude oil viscosity, and make water droplets easy to settle. The most commonly used method is to add chemical demulsifiers, which are injected from the wellhead and mixed with the fluid to reach the emulsification interface, and adsorbed to the emulsifier through polarity differences, neutralizing the emulsification, making the water droplets merge and increase, and achieving separation. In addition, demulsifiers are also used for desalting in refineries. Imported crude oil contains 1% water, which dissolves a large amount of salt and damages the catalyst. Fresh water is added and demulsifier is used to condense salt. Under the action of electrostatic grid and desalting demulsifier, condensation and dehydration are achieved to produce crude oil suitable for refining.
Demulsifiers for Crude Oil Desalting
Demulsifiers are specialized chemical additives designed to destabilize and break crude oil emulsions (W/O or O/W) in refinery desalting processes, enabling efficient water separation and salt removal. These formulations work by neutralizing natural emulsifiers (e.g., asphaltenes, naphthenic acids), weakening interfacial films, and promoting droplet coalescence under electrical fields. UNPChemicals’ DEMET series employs a synergistic blend of resin oxyalkylates (charge neutralization), block copolymers (interfacial rheology control), and polyacrylates (solid wettability modification) to handle challenging crudes—including high-TAN, high-asphaltene, or heavy oils—while maintaining consistent performance across wide temperature (80–150°C) and pH ranges. The optimized chemistry ensures enhanced desalting efficiency, reduced oil-in-water content, and minimized downstream corrosion risks.
What are Demulsifiers?
Demulsifiers are surface-active agents that accelerate the separation of water from crude oil emulsions by destabilizing the protective interfacial films surrounding water droplets, enabling efficient dehydration and desalting in refinery processing.
What are the main types of Demulsifiers?
Key chemistries include alkylphenol resins, polyalkylene glycols, epoxy resins, polyols, and advanced polymer blends like UNPChemicals' DEMET series which combines multiple mechanisms for comprehensive emulsion breaking across diverse crude slates.
Where are Demulsifiers commonly applied?
These chemicals are essential in refinery desalters, production separators, and crude oil terminals where stable emulsions form during production, transportation, or processing - particularly for heavy, acidic, or high-asphaltene crudes that create challenging emulsion systems.
How do you select the right Demulsifier?
Selection requires bottle testing with representative crude samples, evaluating performance metrics like water drop rate, interface quality, and BS&W levels while considering process temperatures, shear conditions, and the presence of problematic components like asphaltenes or fine solids.
Why choose multi-component Demulsifiers like DEMET?
Advanced formulations like DEMET provide superior performance by combining complementary chemistries that address multiple emulsion-stabilizing mechanisms simultaneously, outperforming single-component products - especially for complex refinery feeds containing varying proportions of asphaltenes, naphthenic acids, and production chemicals.
What makes DEMET effective for challenging crudes?
The balanced formulation of resin modifiers, polymeric components, and ester-based synergists in DEMET demulsifiers provides broad-spectrum performance across heavy/light crude blends, high-TAN crudes, and slops processing - maintaining consistent salt removal efficiency despite feed quality fluctuations.
Demulsifier Supplier
UNPChemicals is a professional and trusted demulsifiers supplier manufacturing high quality and a comprehensive range of demulsifiers tailored to your specific crude oil characteristics and processing requirements. Our DEMET series demulsifiers are specially formulated to ensure efficient oil-water separation and optimal desalting performance.
If you are looking for high-performance demulsifier solutions that deliver fast water drop, sharp interface, and low BS&W in processed crude, feel free to contact our technical team for expert recommendations. We provide customized demulsifier formulations for all your refinery desalting and crude oil treatment needs.