TATNEFT Experts of TatNIPIneft of JSC TATNEFT have developed a new ultrasound based technology to intensify the process of extra-viscous oil (EVO) dehydration.
JSC TATNEFT is developing Ashalchinskoye extra-viscous oil (EVO) field at present. High viscosity and density of EVO, small density difference between oil and water, a high degree of the aqueous phase dispersion, high content of resins and asphaltenes in the oil, which are natural stabilizers, make the EVO emulsion highly resistant to destruction. Dewatering of such oil requires a high dosage of oil demulsifier (not less than 200 g/t), heating temperature not less than 85°C and long settling time (at least 10 hours).
The ultrasonic exposure on the emulsion causes mechanical vibrations in the media accelerating and activating water droplets. This increases the number of the water droplets collisions (coagulation) under optimal conditions of the impact: their linking together (coalescence) and subsequent deposition in a separate phase.
Field tests for EVO dehydration carried out by the Company's professionals at the extra-viscous oil treatment installations of NGDU "Nurlatneft" have demonstrated the effectiveness of ultrasonic treatment for the EVO dehydration. Application of the ultrasonic coalescer for treating the emulsion for 5 minutes at ultrasonic frequency of 50 KHz, specific acoustic power of 100 W/dm3 and the exposure intensity not exceeding 5 W/cm2 allows 2.5-fold reduction of the settling time for the subsequent EVO dewatering reducing the water content to its mass fraction of 0.5 %. The developed technology of EVO treatment with application of ultrasonic exposure allows obtaining commercial oil corresponding to the 1st group of quality.
|
distributed by
|
