Abstract

The cold heavy oil production with sand (CHOPS)is widely applied for heavy oil before the more expensive thermal recovery process. It is matured in 1990s, with low cost. The recovery factor is still considerable. There are two key mechanisms in CHOPS, first foamy oil flow, second wormhole network growth.

Both foamy oil flow and the growth of the wormhole network are modeled, by using the implicit coupling and pseudo coupling. There are several observations from the simulation results. Sand production is treated as an erosion process. Erosion will not occur until the pressure gradient at the wormhole tip region is large enough. Higher oil viscosity (2,000-30,000 cp) is desired for a successful cold production process. High oil viscosity would generate high frictional drag between oil and sand to enhance the sand production. Sand influx directly changes the reservoir stress and improves inflow performance. A very good choice for in situ combustion operation: The high temperature ignition will definitely collapse the wormhole channels and result in high permeability heated channels.