The Effects of Multi-component Thermal Fluids on the Viscosity of Offshore Heavy Oil

作者：Hu S B^*; Guo L L; Liu Y J

来源：Petroleum Science and Technology, 2014, 32(20): 2458-2465.

DOI：10.1080/10916466.2013.841199

• offshore heavy oil
• multi-component thermal fluids
• viscosity reduction
• thermal recovery
• experimental study

Multi-component thermal fluids stimulation is a feasible way to recover offshore heavy oil reservoir. As a new technology, its mechanism of enhanced oil recovery should be understood through systematic simulation experiments and quantitative analysis. Laboratory experiments were carried out to investigate the effects of temperature, natural gas, and various gases (N-2, CO2, or N-2+CO2) on the viscosity of heavy oil from Nanbao block of Bohai offshore oilfield. The results show that in the range of 56 degrees C (reservoir temperature) to 120 degrees C, natural gas saturated and degassed oils are all very sensitive to temperature, and the viscosity is reduced by more than 90% when heated to 120 degrees C; under lower temperature condition, injection of 5MPa N-2, N-2+CO2, or CO2 can significantly reduce the viscosity of natural gas saturated heavy oil, with a viscosity reduction ratio of about 20%, 50%, and 80%, respectively, at 56 degrees C. Therefore, heavy oil production by viscosity reduction can be achieved by raising temperature or through gas injection. Taking into account the equipment, heat loss, and cost of steam injection, the technology of moderate heating, auxiliary gas injection is very promising for the recovery of Nanbao heavy oil.

• 出版日期2014
• 单位东北石油大学