Enhancing heavy oil mobility and drainage induced by reduction of viscosity and density due to temperature increase caused by steam injection is one of the most used methods by the industry. In spite of the vast investigation done in literature for the area of steam injection, the mechanism(s) of heat flow in reservoirs are not fully understood. Understanding heat flow mechanism(s) and temperature distribution, contribute to better optimization of the used steam.
It is attempted in this paper to shed light on thermal recovery and temperature distribution with steam injection from experimental work. Basically, a model reservoir is constructed with heavy oil to be recovered by steam injection. Mapping of temperature propagation within the model reservoir clearly demonstrates fast steam/ temperature propagation to the overburden and then propagate horizontally at the top of reservoir. Hence, top of the reservoir becomes the second heating source of the underlying layers. However, the obtained temperature propagation profiles of simulated heavy oil thermal recovery by steam are different from the experimental data.
Analysis of the temperature distribution shows that at the interface between the heated and cold region of the reservoir are initially contributed by convective heat flow (steam condensate and mobile heavy oil), then conductive heat transfer dominates. As the temperatures reach / close to steady state in the different heated areas, maximum drainage process takes place.
Different simulation and experimental temperature distribution data are compared and showed better agreement between the estimated and experimental data as a function of time, indicating more conductive heat transfer mechanism with time.
It is interesting to observe that in spite of the complexity of different processes taking place, consistent temperature gradients are established within the reservoir. This could lead to a better optimization of steam injection regime.