Method for production and upgrading of oil

Abstract

An integrated process for production and upgrading of heavy and extra-heavy crude oil, comprising (a) reforming of hydrocarbons such as natural gas to produce hydrogen, CO2 and steam (b) separating the produced hydrogen from the CO2, steam and any other gases to give a hydrogen rich fraction and a CO2 rich fraction and steam, (c) injecting the steam alone or in combination with the CO2 rich fraction into a reservoir containing heavy or extra heavy oil to increase the oil recovery, and (d) upgrading / refining of the heavy or extra heavy oil to finished products by extensive hydroprocessing, comprising several steps of hydrocracking and hydrotreating (sulfur, nitrogen and metals removal as well as hydrogenation of olefins and aromatics), using the hydrogen rich fraction.

Description

THE FIELD OF THE INVENTION [0001] The present invention relates to an enviromnental-friendly, integrated process for increased production and upgrading / refining of heavy and extra-heavy crude oil to finished products, based on extensive use of hydrogen to maximise the yield of liquid products, while cogenerating large amounts of steam, CO2 and optionally N2 produced by large-scale natural gas conversion, used for increased oil production. The finished products from upgrading / refining of heavy / extra heavy oils will be predominantly naphtha, kerosene, diesel and fuel oil, shipped separately or blended. THE BACKGROUND OF THE INVENTION [0002] Compared to conventional oil, the utilization of heavy oil (density<20° API, viscosity>100 cP) and extra heavy oil / bitumen (density<10° API, viscosity>100000 cP) is limited because of cost of production and upgrading. However, it is expected that the continued need for petroleum liquids such as transportation fuels will be met in the fu...

AI Technical Summary

Benefits of technology

[0021] According to the present invention there is provided an integrated process for production and upgrading of heavy and extra-heavy crude oil, comprising (a) reforming of natural gas to produce hydrogen, CO2 and steam (b) separating the produced hydrogen from the CO2, steam and any other gases to give a hydrogen rich fraction and a CO2 rich fraction and steam, (c) injecting the steam alone or in combination with the CO2 rich fraction into the reservoir containing heavy or extra heavy oil to increase the oil recovery, and (d) upgrading / refining of the heavy or extra heavy oil by hydroprocessing, comprising hydrocracking and hydrotreating using the hydrogen rich fraction in the hydroprocessing steps. The term “hydrotreating” comprises, as used in the present invention, removal of sulfur, nitrogen and metals as well as hydrogenation of olefins and aromatics.

[0026] Preferably the process comprises the additional step of air separation to produce purified oxygen comprising more than 95%, preferably more than 98% oxygen, that is used as oxidizer in the reforming. The use of purified oxygen in the reforming and separation of the reformed gases, reduces the gas volume in the reactors and the separation units. Accordingly the volume and building costs may be reduced and the separation of hydrogen from the remaining gases is more effective.

[0032] Partial upgrading of the heavy or extra heavy oil in the reservoir makes the oil less viscous. Upgrading in the reservoir may therefore increase the oil production, whereas both upgrading in the reservoir and in a downhole unit will improve the transportability of the oil

[0035] According to an embodiment geothermal heat is used to increase recovery and transport of the heavy or extra heavy oil.

Problems solved by technology

Compared to conventional oil, the utilization of heavy oil (density100 cP) and extra heavy oil / bitumen (density100000 cP) is limited because of cost of production and upgrading.

Due to its high viscosity the primary recovery of heavy oils by conventional methods is low.

A subsequent refining of the synthetic crude is needed to produce finished products with the right quality, but this reprocessing is not very energy efficient since the synthetic crude oil has to be reheated and fractionated.

Moreover, new specification on the sulfur content in transportation fuels normally requires increased hydrotreating in the refineries, a type of processing that consumes hydrogen, thereby contributing to a hydrogen imbalance in the refineries.

The particular high content of residue in heavy oils requires particular refinery configurations to process these crudes, and the high content of metals and carbon residue / asphaltenes in the residue limits the use of catalytic processes available to upgrade the heavy ends of those heavy crudes.

Today, the change in demand pattern has created regional lack of sufficient upgrading capacity in the refining industry, the so-called bottom-of-the-barrel problem.

This, combined with limited hydrogen availability, will probably make it less attractive for conventional refineries to process heavier crudes.

Heavy oils are, due to their physical properties and particularly the high viscosity, difficult to produce and transport.

Due to its high viscosity the primary recovery of heavy oils by conventional methods is low.

Introduction of gases as mentioned above is not sufficient to produce and transport heavy oil and extra heavy oil / bitumen even if oil soluble gases like e.g. CO2 and methane will, dependent on the pressure and temperature of the mixture, reduce the viscosity somewhat.

Images