ENHANCED OIL RECOVERY IN HIGH VISCOUS RESERVOIR USING THE THERMAL PROCESS
New sources of energy should be found to relieve the high demand of energy. Even though heavy oil and bitumen are difficult to produce due to their high viscosity which can be reduced by heating, with increased oil price, the production of these heavy oils are seen viable thus the need for a model that would help make predictions for the future and also take into consideration areal and vertical sweep of hydrocarbons (3D simulator). The ability to be able to optimize the interaction data and decision making during the life cycle of the field is critical. As a result of a heterogeneity of reservoirs, numerical simulators are used to obtain consistent and significant solutions.
For this work, a three-dimensional numerical reservoir simulator is developed for an expansion drive with a high viscous oil. A transient state heat system by conduction with an internal heat source is considered. A temperature simulator is first developed then coupled with a viscosity correlation after which it is then coupled with a diffusivity equation for a single phase flow of an expansion drive reservoir. All the governing equations are discretized using finite difference technique; iterative linear solver with the aid of MATLAB code is used to solve the system of linear equations.
This work aims to look at the effect of temperature on pressure drop through viscosity. It is realized that an increase in the heat source introduced a rise in temperature which in turn decrease the viscosity across the system. The pressure across the system is seen to be sustained even though it is declining thus the pressure being maintained.
1.1 General Introduction
Reservoirs act differently due to varying range of both rock and fluid properties and thus must be treated uniquely. During production, reservoirs are allowed to naturally produce their hydrocarbons until when production rates are mostly not economical viable then other support systems are used. Primary recovery is the natural stage of the reservoir to be able to produce without support thus depending on reservoir’s internal energy. There are different drive mechanisms known as a results of different energy sources. The drive mechanism of a reservoir is not known in the earlier life of the production but can be seen from production data with time. The knowledge about the reservoir’s drive mechanism can help improve reserves recovery and supervision during its middle and later life. The important drive mechanisms include: Rock and liquid expansion drive, solution gas/ depletion drive, Gas cap drive, Water drive, Combination drive and Gravity drainage drive.