Three-dimensional physical simulation of thermochemical flooding for offshore heavy oil

Key words:  offshore oilfield  heavy oil  three-dimensional physical simulation  thermochemical  numerical simulation

Abstract:

A large-scale three-dimensional equipment for physical simulation experiment was designed and manufactured based on the geological characteristics of a heavy oil reservoir of Bohai Sea. The enhancing effect of chemical additives and flue gas on the thermal recovery of heavy oil during steam flooding was studied. And the distribution characteristics of temperature and residual oil saturation in the three-dimensional model were analyzed. Then a numerical model was established according to the conditions of three-dimensional physical model to verify the accuracy of the physical simulation experiment. The results show that the single well recovery of thermochemical flooding increases by 5.89％ in comparison with the conventional steam flooding. The enhanced thermochemical flooding by adding flue gas greatly expands the thermal sweep area of the reservoir and improves the oil recovery, due to the heat insulation effect of the flue gas and the plugging effect of the foam. The water cut of the single well decreases by 28.17％, and its oil recovery increases by 37.19％. Meanwhile, the results of numerical simulation fit well with that of physical simulation experiment.