Sustainable method for recovery of petroleum

Abstract

The present invention comprises a method of Enhanced Petroleum Recovery (EPR) combining technical, economic, environmental and social effectiveness to increase the recovery factor of onshore or offshore fields having a high degree of exploitation, more precisely through the use of a substance miscible with the diverse types of petroleum of low fluidity found in various regions. More specifically, the present invention refers to the use of solvents such as light liquid fractions of petroleum, for example diesel oil and gas oil, a light petroleum, and the essential oils derived from renewable sources such as for example biodiesel, used pure or mutually admixed in any proportion, for injection into a geological formation through an injection well, there resulting a final mixture (petroleum / injected solvent) presenting much lower viscosity and much greater fluidity than the original petroleum, having an impact throughout the petroleum production chain. The present patent presents real gains in all phases of the production chain.For the purposes of the present invention biodiesel is understood to be oil having characteristics similar to diesel produced from mineral sources, however having been produced from renewable sources, usually agricultural sources.

Description

FIELD OF THE INVENTION[0001]The present invention refers to a sustainable method for increasing the recovery of petroleum from petroleum-bearing subterranean formations, particularly formations wherein petroleum is found as oil which is too viscous to flow or be pumped.[0002]More particularly the present invention refers to a method of recovery (extraction) of petroleum from the original geological formation utilising injection of diesel and / or biodiesel oil through the injection well, reducing the viscosity of the petroleum, dissolving heavier and immobile petroleum fractions and traversing the reservoir acting through the sweeping and displacement effectiveness, increasing oil recovery and the proven reserve.BACKGROUND OF THE INVENTION[0003]In view of the increasing need for energy one of the great challenges of the petroleum industry worldwide is achieving maintenance of production to satisfy current demands.[0004]The model currently followed aims to maintain production and reser...

AI Technical Summary

Benefits of technology

[0029]The present invention presents a method of Enhanced Petroleum Recovery combining general, economic, environmental and social effectiveness in order to increase the recovery factor of onshore or offshore fields, more precisely through the use of a miscible substance for use in reservoirs, having the objective of reducing viscosity and fluidifying the petroleum. Such substance is selected from the group consisting of diesel oil or fractionated gas oil from petroleum, or even biodiesel, being similar and derived from plants, or light oil, which products may be utilised pure or with additives, in an isolated manner or together with other fluids or methods such as: steam, polymers, etc. Such substances, subject of the present patent, require to be highly-miscible with the oil contained in the geological formation wherein it is intended to act, injection being executed through the injection well and traversing the entire reservoir to the production well, which in the petroleum context represents Enhanced Petroleum Recovery (EPR).

Problems solved by technology

In general the currently-existing technology having this objective has been solely concerned with the technical and economic effectiveness of the processes employed and thus the solvents employed heretofore cause environmental disequilibrium, both on the surface, having consequences for the ecosystem and mankind, and within the environment of the geological reservoir, causing chemical, physical, physico-chemical and biological disequilibrium in said environment.

The well is then put into production when petroleum is then produced together with the gas utilising conventional production equipment and techniques, however the fact of struggling with gas and injecting the same through the production well raises other questions in terms of safety and effectiveness of the procedure.

This procedure is expensive and when crude petroleum requires pumping over long distances recirculation of the viscosity-reducing agent becomes complicated.

This is a process to ensure flushing pipelines and lines, it is not a method for recovering petroleum which acts within the reservoir.

In both cases referred to the use of gases involves very delicate situations in terms of operational and safety matters, and as to the materials which polymerise, these may also prevent some areas of interest in the formation being prevented from subjection to more efficient washing.

The effectiveness of the process is low because such fluids have a tendency to create preferential channels in regions or beds of high permeability.

In many cases wherein the oil is of high viscosity the process of secondary recovery ends by being abandoned because the oil can no longer be economically produced due to the high ratios of water injection to oil produced.

Images