Description: The vapor extraction (VAPEX), regarded as a cold enhanced oil recovery process applies either pure or mixed solvent gases to reduce the viscosity of heavy oil and bitumen. In this study a mechanistic model is proposed for the VAPEX process modeling. Pseudo convective-diffusive Mass transfer combined with fluid flow equations were solved with proper initial and boundary conditions. The VAPEX process was divided into three different stages in terms of operation time: Early time (unstable stage), spreading stage, and falling stage. Modeling of spreading stage and falling stage is the objective of this study. Effects of drainage height and permeability on the oil production rate are investigated. The scale-up results indicate that the drainage rate in the VAPEX process is proportional to the height to the power of 1.274 in the height range examined in this study.

Description: TPS (Two-Phase Software) uses a modelling approach for the pressure loss calculation which is a hybrid between the rigorous and empirical methods. This means the software uses well known empirical correlations which are applied to a differential pipe length, allowing for a flash calculation, liquid holdup and flow regime to be determined for each segment and acknowledges that the pressure loss per unit length changes as the two-phase mixture flows along the pipeline.