Method for increasing oil recovery of heavy oil reservoirs through composite heat carrier

Abstract

The invention discloses a method for increasing oil recovery of heavy oil reservoirs through a composite heat carrier, and particularly relates to a method for increasing oil recovery of heavy oil reservoirs through a composite heat carrier composed of hot water, a gas and a chemical agent. According to the method, crude oil recovery is increased, by injecting hot water and flue gas generated by boiler burning together into an oil layer, and by injecting a foaming agent by means of slug injection. The method includes the steps of a, injecting a mixture of hot water and flue gas 0.15-0.2 times the pore volume of a formation; b, injecting foaming agent solution into a water injection well for 25-30 d; c, injecting the hot water and flue gas mixture for 60-80 d; d, repeating the steps b and c. Water (vapor) can be effectively blocked from channeling, vapor wave and volume are increased, heavy oil recovery is substantially increased, and as the flue gas generated by burning is injected directly underground, heat efficiency can be improved and environmental pollution can also be reduced.

Description

Technical field [0001] The invention relates to the technical field of oil production in oil fields, in particular to a method for improving the recovery efficiency of heavy oil reservoirs with a composite heat carrier composed of hot water, gas and chemical agents. Background technique [0002] Heavy oil occupies a large proportion of the world's oil and gas resources. China's heavy oil asphalt resources are widely distributed. More than 70 heavy oil fields have been discovered in 12 basins, and heavy oil resources are abundant. The exploitation of heavy oil has great potential, and with the reduction of light oil reserves, the proportion of heavy oil exploitation in the 21st century will continue to increase. [0003] Steam huff and puff and steam flooding are currently commonly used traditional techniques for enhancing the recovery of heavy oil. However, due to the heterogeneity of the reservoir, high permeability zones and micro-fracture zones often become steam channeling chan...

AI Technical Summary

Problems solved by technology

[0003] Steam huff and puff and steam flooding are traditional heavy oil recovery technologies commonly used at present. However, due to the heterogeneity of reservoirs, high-permeability zones and micro-fracture zones often become channels for steam channeling. , hot water) and the displaced phase (heavy oil) have a great difference in viscosity, resulting in steam viscosity fingering and a large density difference, which causes gravity differentiation of the displacement phase in the oil layer, resulting in overburden problems, which seriously affect the displacement phase. Therefore, there is an urgent need for an effective method to suppress steam overburden and steam channeling, expand steam sweep coefficient, and improve heavy oil recovery.