Study on Demulsification Technology of Heavy Oil Blended in Xinjiang Oilfield

Abstract

HYW (Hong Yi Wu line) heavy oil emulsion in Xinjiang Oilfield (Karamay, China) is a kind of heavy oil with high viscosity and high emulsification. Its viscosity reaches 120,000 mPa·s at 40 °C. The emulsion has no demulsification. Even if the demulsification temperature reaches 90 degrees, the concentration of demulsifier reaches 260 mg/L. In this paper, a new process of thermochemical demulsification of heavy oil after blending is studied. First, SE low-viscosity oil with viscosity of 640 mPa·s and water cut of 90% was selected as blended oil. Study the viscosity of SE line and HYW line at different temperatures after fully blended. The results show that the heavy oil blended model conforms to Bingham model. When the temperature is 40 °C and the content of SE line is 30%, the viscosity is less than 10,000 mPa·s. With the increase of temperature, the viscosity continues to decline. When the temperature exceeds 80 °C, the viscosity is less than 1000 mPa·s. The final design SE line content is 30%, the demulsification temperature is 70 °C, and the demulsifier concentration is 160 mg/L as the best demulsification parameter. The field results show that the demulsification rate of heavy oil in this process reaches more than 90%. This experiment lays a foundation for demulsification of high emulsified crude oil developed by heavy oil in Xinjiang oilfield.

Prevention and Removal of Naphthenate Deposits in Oil and Gas Production—Historical Background and Novel Attitude towards Inhibition and Solution

“…Then, bottle tests of demulsifiers/naphthenate inhibitors obtained from an oil rig were conducted (naphthenate inhibitors are often part of commercial demulsifiers; moreover, the strong acids can be used as demulsifiers themselves). In general, the temperature and concentration of the demulsifier had the greatest effects on the amount of separated water [16].…”

Demulsification Methods for Heavy Crude Oil Emulsions. A Review

“…However, the technology of demulsification using a mixture has not yet been reported. Zou et al 56 investigated a new process of thermochemical demulsification of heavy oil after mixing with light oil. The results of field tests show that the degree of heavy oil demulsification in this process reaches more than 90 %.…”

“…The ultrasonic waves transfer energy in the form of pulsations and propagate in the emulsion. The emulsion continuously absorbs the vibration energy it carries and converts it into heat energy, which can increase the temperature of the emulsion and promote demulsification and dehydration 56 . In addition, vibration can evenly distribute natural emulsifiers in crude oil, increasing its solubility and reducing the mechanical strength of the oil-water interface film.…”

“…The separation efficiency of crude oil and water can be >93 %. The application of ultrasonic technology for oil-water demulsification can reduce energy consumption and operating costs, which has good development potential 56 .…”

Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield

“…Suspended particles also have a great impact on the stability of the emulsion, which are closely arranged on the interface layer of the emulsion and form a “Pickering” emulsion, greatly enhancing the stability of the emulsion [ 15 ]. Thermochemical demulsification, electrochemical demulsification [ 16 ], and ultrasonic demulsification are mostly applied to treat this emulsion. According to the discharge and treatment requirements of a typical refinery, Zhang et al studied the fluctuation of desalting wastewater quality [ 17 ].…”