METHOD FOR INJECTING NON-CONDENSABLE GAS OR IN-SITU COMBUSTION TO RECOVER REMAINING OIL IN A HEAVY OIL RESERVOIR WITH BOTTOM WATER

摘要

The present invention discloses a method for injecting non-condensable gas or application of in-situ combustion to recover remaining oil in a heavy oil reservoir with bottom water, comprising the following steps: drilling a new horizontal well in an oil layer between the existing horizontal production well location and the bottom water layer; preheating the new horizontal well; after the horizontal section of the horizontal well is in thermal communication with the upper steam/gas chamber, performing gas injection in existing wells to maintain pressure slightly higher or similar to the pressure of the bottom water layer, and converting the horizontal well into a continuous production well; drilling a vertical well in the unswept reservoir area; establishing a fluid communication in the oil layer between the vertical well and the horizontal well, injecting air or oxygen into the vertical well; in the later stage of the horizontal well, stopping gas injection and gradually reducing the pressure in the steam/gas chamber until the end of oil production. The present invention produces the remaining oil in the region below the current horizontal well and near the toe, which greatly improves the ultimate recovery factor of the oil reservoir.