Process for upgrading heavy oil and bitumen products

Abstract

A process for upgrading bitumen recovered from an oil reservoir without hydrogen production is particularly useful in field upgrading applications. In this process, recovered bitumen enters a fractionator and is contacted with heated gases from a fluidized bed reactor. The bitumen and heated gases are fractionated into segregated products including at least a liquid pitch, unstable fractions, and an upgraded liquid product. The liquid pitch is introduced into the reactor to produce a vapor phase liquid product; the reactor comprises solid particles moving through the reactor and a fluidizing gas fluidizing the solid particles at a conversion temperature which is suitable for facilitating the conversion of at least some of the liquid pitch into the vapor phase liquid product. The heated gases comprising the vapor phase liquid product and fluidizing gas are directed from the reactor to the fractionator to contact the bitumen stream. In this process, enough of the segregated unstable fractions are burned that the liquid product and any remaining unstable fractions meets pipeline specifications without hydrogen treatment of any of the remaining unstable fractions.

Description

FIELD OF THE INVENTION[0001]This invention relates generally to oil processing, and in particular, to a system for upgrading heavy oil and bitumen products.BACKGROUND[0002]As conventional access to crude oil declines, more emphasis has been placed upon devising ways to economically exploit the abundant ultra-heavy oil (also known as “bitumen”) reserves present most notably in Venezuela, Canada and the United States. Depending upon the reserve, some of this oil is not recoverable by conventional means, as the oil will not flow at the ambient temperature. In Canada, and specifically in Alberta the majority of bitumen is present as a semi-homogenous mixture of solid hydrocarbon and inorganic sand and clay, referred to as “oil sand”. The recovery of bitumen in Canada introduces an additional challenge, as the heavy oil / bitumen must first be recovered from the sand aggregate prior to introduction into upgrading units. One popular method of oil recovery from oil sands is thermal recovery,...

AI Technical Summary

Benefits of technology

[0022]In the fractionator, the heated gases can be contacted with the bitumen such that the boiling temperature of volatile material in the bitumen is reduced, thereby enabling fractionation without use of atmospheric and vacuum columns, which are elements of a traditional upgrading flowsheet.

[0023]The process and system according to the above aspects of the invention provides advantages over prior art systems and processes by reducing the capital scope beyond eliminating the need for hydrogen generation, and providing additional benefits as will be described.

Problems solved by technology

Depending upon the reserve, some of this oil is not recoverable by conventional means, as the oil will not flow at the ambient temperature.

The recovery of bitumen in Canada introduces an additional challenge, as the heavy oil / bitumen must first be recovered from the sand aggregate prior to introduction into upgrading units.

A significant amount of infrastructure is required to support the PUG and SUG facilities in prior art systems.

The conventional upgrading system is energy and resource intensive, complex, and expensive to set up and maintain.

Reasons include: the remote and localized nature of oil sand reservoirs result in expensive labour costs; the use of expensive diluent (a low molecular weight hydrocarbon) to assist in the separation of the heavy oil from the mixture of bitumen and water that is initially recovered at surface by the thermal recovery process; and, SAGD, CSS and other thermal recovery processes are very energy intensive, requiring high pressure steam that is typically produced by combusting natural gas.

The benefits derived from the PUG processes based on hydrogen addition are derived at the expense of significant incremental capital and operating expense.

Many of these costs are the result of incorporating hydrogen production equipment and processes, expensive and complex bitumen / heavy oil conversion reactors in hydrogen service, as well as costs associated with catalyst and incremental feedstock for hydrogen production.

This limits the degree of integration that can be achieved with thermal production, which typically boasts ˜20,000-30,000 bbl / d of production.

To date there have been no commercial applications of the field upgrading concept, as no system utilizing PUG technology has proven economic at such smaller scales.

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