000 02546nab a2200193 4500
005 20260520001805.0
008 260224s2009 xxu
245 0 0 _aDynamic modelling of solution-gas drive in heavy oils
260 _a
_b
_cdic. 2009
270 _a23/06/2010 ; 23/06/2010
300 _a8 p. ; 39-46
520 _aTranscripción del resumen del autor. Some heavy oil reservoirs in Canada show atypically high production rates and high primary oil recoveries under solution-gas drive. Much attention has been given to the anomalous behaviour observed in such heavy oil reservoirs, and several models have been suggested to explain these anomalies. There are two classes of effects responsible for the unusual behaviour of solution-gas drive in heavy oil reservoirs, including fluid effects and rock/geomechanical effects. This study focuses exclusively on fluid effects. In at least two ways, solution-gas drive in heavy oils differs from that in light oils. In heavy oils, the concentration of gas in the oil can be significantly greater than the equilibrium value; the oil could be significantly supersaturated. Additionally in heavy oils, recovery and gas mobility show rate dependent behaviour. Both of these effects are taken into consideration in this study. In this paper, we develop a dynamic model that captures many important processes that affect heavy oil recovery. The non-equilibrium early time behaviour is modelled by introducing a kinetic equation describing the rate of evolution of solution gas into free gas. The equation is derived based on a phenomenological analysis which takes into account bubble nucleation and growth. A second component of this model captures the low gas mobility in heavy oil reservoirs and its dependency on viscous forces. To account for the effect of viscous forces on gas mobility, relative permeability functions are introduced that not only depend on gas saturation but also on local oil phase velocity and viscosity. While many of the previous models apply several kinetic equations associated with a large number of parameters, we have shown that the modifications suggested in this study enable predicting many of the unusual behaviours observed in solution-gas drive in heavy oil reservoirs, using only one kinetic equation with a smaller number of fitting parameters.
581 _a12
773 0 _tJournal of Canadian Petroleum Technology
_g48
942 _cARTICULO
100 1 _aShahvali, M.
_943119
100 1 _aPooladi-Darvish, M.
_939843
999 _c171295
_d171295