High Frequency Antiscaling in A Watered Oil Gathering System

In Daqing Oil Field, dual string watered gathering is adoped for the paraffinic base oil with high wax content, high viscosity and high pour point. Chemical additive method has been in use since the 80's to prevent scaling due to watering. Although it has a performance of 90%, this method is not a good solution because of the following disadvantages: high cost, degradation at 90 C water, corrosion to pipeline, pollution to environment, complicated dosing process, prevention without scale cleaning. Therefore, introduced is the high frequency antiscaling method, the concept of which is that the watered medium in high frequency field sees polarization and cavitation with the effect of high frequency electromagnetic waves. Polarization results in high polarity, molecular rearrangement, incapability of crystallisation between calcium and magnesium ions, loose scale crystal, and brittle scale particals. Cavitation, on the other hand, contributes to scale prevention and removal by convoluting and decreasing the surface tension of the medium in high frennencv electric field, lagging scale deposit, breaking the affinity between scale and metallic wall, and loosening and softening the existing seale. Best seale prevention and removal can be achieved only by reasonable process selection and impendence matching between main and associate machines.