Test And Application Of Heavy Oil Viscosity Reduction Technology In Oil Field

The formation of Fuyu Oilfield weakly viscous oil is mainly due to the water drive cold damage wax precipitation and depressurization of crude oil dissolved gas overflow and other reasons lead to significantly increased the viscosity of crude oil, increase of oil-water viscosity ratio, water flooding water rose quickly, refers to the phenomenon more obvious, harvest rate is reduced. Weak heavy oil thermal recovery methods developed to form a certain scale, more obvious effect of increasing production, but the high cost of mining. The two round of heat recovery and steam injection effect is poor, the total oil increase is reduced, only about 45% of the round.The next step should deepen the research on viscosity reducing mechanism, to further improve the system performance and system series of research, viscosity profile control was discussed in detail and viscosity reduction drive effective characteristic analysis, summarizing the previous research work, to carry out a new block in the implementation.The project in eastern area in Fuyu Oilfield heavy oil block implementation of visbreaking cold production technology, respectively, to carry out the reduced viscosity mechanism studies, reducing viscous system selection and evaluation, viscosity reduction and optimization of injection parameters and the injection optimization, viscosity reduction factors and the relevant technology research.Water soluble viscosity reduction system is mainly through the formation of O / W emulsion, the flow of crude oil when the oil film and oil film between the friction is changed into the water film and water film between the friction, so that the oil flow resistance is greatly reduced, viscosity is greatly reduced.Through the indoor experiment analysis and evaluation, the lower viscous system compatibility, viscosity reduction rate, emulsifying properties, interfacial tension, washing efficiency and stability of analysis and evaluation, and screened out a suitable Fuyu Eastern viscosity reduction system and further optimize the performance of the system. Through the experiment of material model and numerical model, the degree of recovery was analyzed under different injection quantity and injection mode, and the injection parameters and injection method were optimized. Using online viscosity reducing technology, the way of online injection well, injection is convenient, and the construction cost is saved.In view of the characteristics of Fuyu Oilfield heavy oil resources and the high cost of steam huff and puff, second round of stimulation effect variation, it is necessary to explore new enhanced oil recovery rate, to further improve the water flooding development effect, the greatest degree of mining of remaining oil potential.