Effects of high-frequency pulsed electrical field and operating parameters on dehydration of SAGD produced ultra-heavy oil

Droplet deformation under pulsatile electric fields

“…This is because, increasing the frequency, a point is reached where the period of the electric field becomes shorter than the mechanical relaxation time and hence the frequency of droplet oscillation can no longer follow the field frequency [12]. At a high frequency (f 500 Hz), the deformation process is similar to the pattern of constant electric field [44]. Lesaint et al [45] reported that the root mean square On the application of the electric field an overshoot occurs in the droplet deformation, but for all the three wave forms a constant asymptotic value of deformation ratio is obtained which is nearly coincident with the constant electric field.…”

Electrocoalescence of water droplets in sunflower oil using a novel electrode geometry

“…4b (ii)), the actual intensities applied to the emulsions decrease significantly, and become actually lower than that of 300 V mm -1 , resulting from the occurrence of short-circuiting. So at high intensities, the decrease in efficiency is due to a lower average field intensity caused by short-circuiting as well as the occurrence of droplet break-up and partial coalescence which produces tiny secondary droplets [3,14,15,23,40,41]. Interestingly, different waveforms correspond to different optimum intensities, i.e.…”

“…Moreover, some oil production methods, e.g. steam-assisted gravity drainage (SAGD), generate a large amount of water, which has reached as much as 90 wt% in recent years [3]. As a consequence, stable water-in-oil (W/O) emulsions are readily formed during crude oil production stage, causing detrimental problems in the oil industry, such as equipment corrosion, catalyst poisoning and extra transportation cost [2,4].…”

“…Particularly, for dropdrop coalescence, the threshold frequency depended on the pulsatile field amplitude and initial droplet size. Li et al [3] carried out investigations on the electro-dehydration of crude oil emulsions, and found that the frequency of the applied voltage had a notable influence on the dehydration efficiency.…”

Self-Excited Codirectionally Magnetically Compensated Rotating Ranging Method

“…Due to the high viscosity, the heavy oil in the oil layer is usually featured with high flow resistance and sometimes even not able to flow. Consequently, it becomes inefficient or even impossible to exploit these oil reserves using conventional oil and gas exploiting approaches [2,3]. The safe and efficient exploiting of such unconventional oil and gas resources is of considerable significance to the national economic development.…”