With the proposal of the oil control indicator system during the 14th Five Year Plan, we aim to achieve energy self-sufficiency within five to ten years. The recovery rate of domestic oil fields will also be increasing, and the composition of the produced liquid will also be constantly changing. Water in oil gradually transforms into oil in water, changing the properties of the oil-water interface, reducing interfacial tension and membrane strength are the core issues of crude oil demulsifiers.
The newly produced crude oil water usually contains salt, and the water forms a relatively stable lotion state with the crude oil. Such crude oil can easily lead to corrosion of production equipment and scaling on the inner walls of pipelines during crude oil storage and processing. So it is necessary to add demulsifiers to achieve dehydration and desalination, so that the water in the crude oil accumulates, the salt dissolves in water, and ultimately the formed water droplets will precipitate.
When paraffin crude oil contains a small amount of gum and asphaltene, the addition of demulsifiers generally has a good demulsification effect, but there is more dehydration and oil, indicating a high hydrophilicity. When the content of gum and asphaltene is high, there is less dehydration and oil, making it relatively difficult to break the emulsion. Pay attention to functionality when selecting demulsifiers. Oil soluble demulsifiers mainly diffuse in molecular form, with fast speed and good dehydration effect. The water-soluble demulsifier first moves from the water phase to the oil phase, with a relatively long path and a slower demulsification speed. Furthermore, a single demulsifier has poor applicability, and multiple combinations of demulsifiers have synergistic effects, resulting in better demulsification and dehydration effects. The concentration ratio of demulsifiers can also affect the effectiveness of use. But the higher the concentration, the better. After reaching the critical aggregation concentration, the demulsification effect is counterproductive. It is also important to find the critical aggregation concentration point. The main function of crude oil demulsifiers is to have a strong attraction to the oil-water interface. After demulsification, the emulsified water droplets come into contact and aggregate with each other, and the condensed water droplets are separated from the connected form to complete the entire process.