Characteristics Of High Water Cut Crude Oil System

At present Daqing oilfield has been in the production period of super high water cut. Compared with initial stage of development, produced fluids have many changes in properties. Based on test data from inside experiments, this paper mainly introduces some special properties of super high water cut oil system and its internal phase, consisting of several parts as follows: (1)Present how and under what conditions to prepare super high water cut system and its internal phase. Analyze separation properties of oil from water in the system. (2)Identify the type of the internal phase of super high water cut oil system by means of wetting filter paper. Discuss the effect of emulsion breaker on the type of super high water cut oil system. Analyze the type and water components of super high water cut oil system. (3)Test the rheological properties of the internal phase of super high water cut system by HAAKE rheometer. Discuss the effects of temperature and emulsion breaker on the internal phase of the system. (4)Analyze the errors when measuring the viscosity of super high water cut oil system by means of traditional viscosity meter. Present an efficient instrument named pipe equipment with its measuring principle and steps. Measure the rheological properties of super high water cut oil system by means of pipe equipment. Discuss the efforts of temperature, water cut and emulsion breaker on properties of super high water cut oil system. (5)Have a dehydration test on the internal phase of super high water cut oil system by means of automatic electric dehydrator. Discuss the effects of the electric intensity and emulsion breaker on dehydration of the internal phase of super high water cut oil system. (6)Put forward the concept of losing flow point of super high water cut oil system as well as its testing method, by means of which test the losing flow point of super high water cut oil system in different conditions. Analyze effect factors and limitations of losing flow point. Test findings show that super high water cut oil is a (W/O)/W emulsifying system which is very complicated and unsteady and can be divided into 2 layers under still condition. Water in super high water cut oil system consists mostly of free water and a little of emulsified water. Emulsion breaker have a few effects on super high water cut oil system, dehydration efficiency of the internal phase can be increased when putting some emulsion breaker into super high water cut oil system. Super high water cut oil system has good flow behavior at lower temperature, and its apparent viscosity changes a little with temperature but increases with the increase of velocity.