METHOD OF HEAVY OIL PRODUCTION

摘要

The present invention relates to the oil production industry, and more particularly to heavy oil production methods using horizontal wells with steam stimulation of formations. The objective of the claimed method of heavy oil production is to increase heavy oil recovery through the enhanced reservoir sweep efficiency and more precise control of uniform steam chamber heating by controlling steam injection and product recovery conditions. To attain this objective, a pair of horizontal injection and production wells is used, with their parallel horizontal wellbores being spaced one above the other in the vertical plane of the productive formation. The wells are completed with tubing strings for simultaneous heat carrier injection and product recovery. The method comprises steam injection, formation heating with steam chamber creation, product recovery through the tubing string of the production well and control of formation and well technological parameters. The novelty of the method is that the ends of the tubing strings are placed at the opposite end portions of the horizontal sections of the wellbores, and heating of the reservoir is started with the injection of steam into both wells. The interwell zone of the productive formation is heated thereby reducing heavy oil viscosity. A steam chamber is formed as the result of steam injection, the steam collecting at the top of the productive formation as the steam chamber grows. The produced water salinity is measured 2-3 times a week and the relation between the produced water salinity salinity and the uniformity of steam chamber heating is analyzed. The results of the salinity measurements are used for maintaining uniformity of steam chamber heating by controlling the heat carrier injection or the product recovery until a stable value of the produced water salinity is obtained.