METHOD OF HIGH-VISCOCITY OIL PRODUCTION Russian patent published in 2003 - IPC

FIELD: oil production with use of heat mainly from reservoirs with high- viscosity and heavy oil. SUBSTANCE: method includes lowering into casing string of tubing strings down to perforation interval and supply through tubing string of heat carrier and lifting of product through annular space. According to invention, two tubing strings are lowered into casing string. The first tubing string is lowered to beginning of perforation interval and the second is lowered through the first tubing string down to end of perforation interval and heat carrier is supplied through it. Supplied to casing string - the first tubing string annulus is gas. Product is lifted through space between tubing strings. After provision of preset injectivity, lifting of product is discontinued. Heat carrier is injected up to rated volume, and gas supply is continued. Space between tubing strings is filled with gas and maintained in this state. Well is shut-in for thermocapillary impregnation up to beginning of intensive lowering of fluid mobility in bottom-hole zone. Pressure in well is released and incoming product is withdrawn till reduction of production rate under natural operating conditions of formation. Cycle of heat carrier injection and product withdrawal is repeated until formation with producing well of zone with movable fluid. Producing well is transformed into injection one. Product is withdrawn through producing well. EFFECT: reduced energy losses of heat carrier and increased radius of producing formation heating. 2 cl, 3 dwg, 1 ex