The influence of the HLB value range of non-ionic demulsifiers on their demulsification effects
The range of HLB values of non-ionic demulsifier product has a significant impact on their demulsification effects, mainly reflected in the following aspects:
1).The Mechanism of Hydrophilic-Lipophilic Balance for demulsifier dewatering
The role of non-ionic demulsifier product is to disrupt the stability of oil-water emulsions and facilitate the separation of oil and water. The HLB value determines the degree of hydrophilic-lipophilic balance of the demulsifier product molecules. When the HLB value of the demulsifier product is within an appropriate range, it can function well at the oil-water interface. If the HLB value is too low, the demulsifier additive is too lipophilic and will dissolve more in the oil phase, making it difficult to interact effectively with the oil-water interface, resulting in poor demulsification effects. At this time, the demulsifier additive may not be able to effectively destroy the emulsifying film on the surface of the oil droplets in the emulsion and the oil droplets are difficult to aggregate and separate. Conversely, if the HLB value is too high, the demulsifier additive is too hydrophilic and will dissolve more in the water phase. Similarly, it is difficult to form an effective effect at the oil-water interface and cannot achieve good demulsification. In this case, the demulsifier additive may not be able to effectively change the properties of the oil droplet surface, making it difficult for the oil droplets to coalesce.
2). Adaptability to Different Emulsion Types Different types of oil-water emulsions, such as water-in-oil (W/O) and oil-in-water (O/W) emulsions, have different requirements for the HLB value of the demulsifier for oilfield. For water-in-oil emulsions, non-ionic demulsifier for oilfield with a lower HLB value are usually required. Such demulsifier for oilfield can interact better with the oil phase, penetrate the emulsifying film on the surface of the oil droplets and disrupt the stability of the emulsifying film, promoting the aggregation and separation of the oil droplets. For oil-in-water emulsions, demulsifier for oilfield with a higher HLB value are needed. Such demulsifier for oilfield can disperse better in the water phase and interact with the surface of the oil droplets to change the surface properties of the oil droplets and achieve demulsification.
3). Specific Influences in the Demulsification Process
--Oil Droplet Aggregation: Non-ionic demulsifier dewatering within the appropriate HLB value range can promote the aggregation of oil droplets. The adsorption of demulsifier dewatering molecules at the oil-water interface can reduce the repulsive force between oil droplets, making it easier for them to approach and coalesce into larger oil droplets. If the HLB value is not appropriate, the demulsifier dewatering may not be able to effectively promote oil droplet aggregation, resulting in poor demulsification effects.
--Sedimentation and Separation: The demulsified oil droplets need to be separated from the water phase through sedimentation and other methods. Demulsifier additive for crude oil with an appropriate HLB value can make the oil droplets have appropriate hydrophobicity, which is conducive to the rapid sedimentation of oil droplets under the action of gravity. However, if the HLB value is inappropriate, the oil droplets may be difficult to sediment due to excessive hydrophilicity or lipophilicity, affecting the demulsification effect. In conclusion, the range of HLB values of non-ionic demulsifier additive for crude oil plays a key role in their demulsification effects.
It is necessary to select demulsifier additive for crude oil with an appropriate HLB value range according to the specific properties of the oil-water emulsion to achieve the best demulsification effect.