Abstract
Profile control by steam foam is commonly used as an effective EOR method for the development of heavy oil reservoirs. However, due to the limited shut-off capacity of foams, the existence of thief zones or high-conductive layers will result in short validity period and poor efficiency. Therefore, steam foam profile control process assisted by stiff particles (SFPCASP) is presented, i.e. stiff particles are firstly injected into the reservoir to plug high-permeability zones, and then steam foam is injected.
The objective here is to establish a numerical method to simulate the combination process. A three-dimensional, three-phase, five-component mathematical model is put forward, which takes into account the principal physico-chemical phenomena and the synergic action. Based on the model, a corresponding numerical simulator is developed, in which FIM (Fully Implicit Method) is applied to ensure the stability and to simulate the reservoir accurately.
An oilfield pilot test has been carried out, and the development scheme is optimized. Compared with only steam foam injection, the best project of the combination process would increase 6.3% of the heavy oil recovery, which effectively demonstrate the validity of the technology. Moreover, the performance of the pilot test was in agreement with the prediction.
In addition, this work provides a platform which can be applied to simulate profile control process by steam foam, by stiff particles or by both of them.
