In September 1998, Genoil decided to develop its own heavy oil upgrading process, based on a
dual approach of visbreaking and hydroprocessing, and, therefore, by adding hydrogen mass, to
obtain an increase in the liquid yields. A hydrogenation process should provide more than 100%
of the fresh feed volume, instead of the 75-80% of the carbon rejection processes.
To start the conceptual and preliminary design work on a hydrotreating process to upgrade heavy
crude oil, Genoil acquired the Visbreaking technology from the Eadie Group and the “Bullet”
technology from the Acquasol Corporation. The Eadie Visbreaking technology was developed
through extensive pilot plant work conducted in the early 1990’s at the Alberta Research
Council. This Eadie Visbreaking technology was modified and enhanced by Genoil. The Bullet
technology is a mixing device which maximizes the mass transfer between two fluids. Full
dispersion of one fluid into the other fluid is achieved (“micro-molecular mixing”) together with
the “super-saturation” of the gas into the liquid. (Although this technology provided excellent
results, Genoil has recently replaced it with an even more effective mixing technology.)
Based on these two technologies, Genoil started developing its own heavy oil upgrading process
concept, with the primary goal of improving sufficiently the properties of the heavy oils to meet
pipeline specifications, removing the need for diluents for transportation and to provide an
advanced upgrading technology for refineries increasingly faced with the option of securing
heavy feed stock and with the need to recover product residuals.
Key features of the Genoil upgrading are the addition of the hydrogen to the feed stock, and the
mixing of the hydrogen with the liquid feed. To confirm this concept, Genoil constructed a
laboratory scale prototype vessel together with the appropriate mixing gas/liquid devices.
Then, Genoil conducted bench scale tests, at various operating conditions over a period of
months, on a Cold Lake Bitumen with an API gravity between 11 and 13°. The main criteria
were to achieve high liquid yields and good product stability (no olefins or diolefins). The original Genoil targets were to upgrade the Cold Lake Bitumen from an 11-13° API gravity to an
API gravity of 19-20° without a hydrotreating catalyst, to an API gravity of 22-24° with small
amounts of catalyst, and to an API gravity of 28-30° with a hydrotreating reactor
(hydroconversion).
These bench scale tests confirmed that “mild” hydrocracking (once-through partial conversion
with hydrogen) of the heavy oil feed stock was the way to obtain stable products. Typical
visbreaking (without hydrogen) would result in an API increase of only 2-3° and in unstable
products. With hydrogen addition, not only the product API could be raised further, but also the
product stability was improved. The bench scale tests indicated also that addition of hydrogen
limited the condensation of asphaltenes, preventing the formation of coke, allowing higher
conversion levels, and resulting in higher product stability together with some desulphurization
of the products.
After testing of the proprietary mixing vessel and devices, the next phase of the program was to
develop a computer model to test the Genoil concept. Over three months, several simulation
studies were conducted to optimize the initial design concept. The simulation results enabled the
updating of the process engineering and instrumentation diagram, complete with mass balances
and heat balances.
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