Effect of Wells’ Connectivity Enhancement on the Performance of Vapor Extraction (VAPEX) Process

Drawbacks of the thermal recovery techniques such as excessive heat loss to the surrounding formations and carbon dioxide emissions during these processes have directed the interests of researchers towards more viable alternatives such as solvent-based recovery techniques (e.g. VAPEX). One of the key parameters to implement a successful VAPEX process is to control the profiles of vapour chamber and consequently improve the areal sweep efficiency. In this regard, an optimum well configuration and well connectivity establishment between the injection and production wells are desirable. The main focus of this research is to extensively conduct series of experiments to investigate the effect of injection/production wells connectivity on the performance of VAPEX process. For this purpose, two large-scale physical models were employed. Propane and propane/carbon dioxide mixtures were selected as the injection solvents in the visual sand-packed physical models saturated with heavy oil sample from Saskatchewan (Canada) heavy oil. Various injection/production scenarios were followed and it was found that the initial connection path between the injector and producer had a significant impact on the vapour chamber profiles and consequently on the ultimate recovery performance of the VAPEX process