FIELD PRACTICE OF INTEGRAL PROFILE CONTROL AND WATER SHUTOFF IN MONGGULIN SANDSTONE RESERVOIR

Monggulin sandstone reservoir is a thin layered heavy oil reservoir with weak edge water. The permeability in different layers in this reservoir is very different, and the oil-water viscosity ratio is 224. After putting into waterflood production, the water fingered forward rapidly, the waterflood effect was poor. There fore, a profile control and water shutoff agent suitable for this reservoir was developed. Meanwhile, properties such as the crosslinking time of the agent, the viscosity of the gel, the thermal stability and the plugging degree of the agent in the porous media and so on were tested and evaluated. This paper demonstrates the method how to prevent or reduce the damage of the agent to the low and middle permeability formations, presents the corresponding technologic measures, and also puts forward the new method for determining the injection pressure based on the lab simulation test and reservoir features. Field test proved that the contradiction between layers of Monggulin sandstone reservoir had been successfully resolved.