Determining method and calculating device for ultra-thick oil steam-injection oil extracting and soaking time

Abstract

The invention provides a determining method and a calculating device for ultra-thick oil steam-injection oil extracting and soaking time. The determining method includes the steps: calculating relations between production time and temperature field distribution of an oil layer at the end of steam injection, actual temperature field distribution of the oil layer at the end of soaking as well as the actual temperature field in time of well opening production and calculating the relation between the effective heating radius and the well opening production time under different soaking time and in consideration of rheological inflection point temperature of crude oil; calculating the relation between drainage radius and crude oil flowing time as well as the relation between maximum relative drainage radius of an oil well and production time under different soaking time; determining the best soaking time. In the determining method, consideration is given to characteristics of rheological inflection points existing in ultra-thick oil and affection of formation pressure upon crude oil flowing, so that the soaking time is determined with the principle of the maximum drainage radius and the production time, and maximum oil production is guaranteed. An embodiment of the invention further provides a calculating device for the ultra-thick oil steam-injection oil extracting and soaking time. The best soaking time can be determined, and the maximum oil production can be guaranteed.

Description

technical field [0001] The invention relates to the technical field of steam injection and oil recovery, in particular to a method and a calculation device for determining the time of holding a well for steam injection and oil recovery of super-heavy oil. Background technique [0002] In oil extraction technology, crude oil is directly extracted from oil wells as crude oil, which is a dark brown or dark green viscous liquid or semi-solid combustible substance composed of various hydrocarbons. Although the basic elements of crude oil are similar, there are many varieties of natural crude oil extracted from the ground in different production regions and different formations. The physical properties of various types of natural crude oil are very different, such as the viscosity of crude oil. Viscosity is a measure of the viscosity of a fluid, and it is a characterization of the friction between the molecules of a liquid when it flows. The viscosity of different varieties of c...

AI Technical Summary

Problems solved by technology

The above method of determining the best soaking time considers that the injected steam should be released to the oil layer in the largest amount as the goal, and the time when the steam disappears in the heating zone and is completely condensed into water, and the pressure in the oil well is stable is determined as the best soaking time time, which makes the oil well soak for too long, and the temperature of the oil layer gradually cools down from the high temperature value, resulting in a large loss of heat, reducing the utilization rate of steam heat energy, and the maximum oil production cannot be guaranteed in actual production.

Images