Underground ignition technology of combustion drive oil layer by injecting steam

Abstract

The invention relates to underground ignition technology of a combustion drive oil layer by injecting steam. Above 3000 meters oil layer, under a strong oxidation effect of the crude oil in the oil layer, the crude oil, namely carbohydrate, and the O2 at a high temperature generate CO2 plus H2O plus heat, thereby reaching the effect of displacement of reservoir oil. The injected steam is used for heating the oil layer so that the oil layer directly reaches the combustible temperature of oil with the help of the heat of the steam and air is directly injected, thus the high and strong oxidation effect that is combustion is generated. The carbon dioxide recombined with multiple drive oil layers is sent out. The thickness is less than 2 meters. A well section is arranged near the bottom of the oil layer. In addition the injection steam has the standard that a steam quantity is not less than 300cm<3>, the injection steam dryness is more than 5%, the injection steam temperature is more than 350 DEG C, and the injection steam pressure is between 2 and 20 MPa. The technology dispenses with physical simulation before ignition, manufactures the underground electric heater, shortens the ignition time and is high in success rate.

Description

technical field

[0001] The invention relates to oil recovery operations in oil fields: oil reservoirs and other ultra-low permeability oil layers in oil fields, using fractured multi-fracture oil layers to plug fractures to create low permeability oil layers, and using the principle of fire flooding oil recovery technology to carry out oil layer transformation technology of carbon dioxide composite polyflooding Among the technologies of plugging fractures in oil layers and creating low-permeability oil layers for carbon dioxide compound polyflooding: fire flooding oil layers uses downhole ignition technology of steam injection. Background technique

[0002] At present: oil reservoirs and other ultra-low permeability oil layers in oilfields have very low oil production rate by conventional oil recovery and are of no value in production. In the early stage, fracturing technology was used for fracturing. After fracturing, some results have been obtained, but the recovery rate is...