Note: Descriptions are shown in the official language in which they were submitted.
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
Method for Processing Heavy Hydrocarbon Oil
FIELD
[001] The invention relates to methods of treating hydrocarbon oil and,
more particularly, to methods for reducing the viscosity and increasing
specific
gravity of heavy hydrocarbon oil.
BACKGROUND
[002] Oil reserves are gradually being depleted and costs related to
processing heavy oil resources, for example oils having API gravity less than
about
23, continue to increase. Large quantities of such heavy oils are available in
oil
deposits in Western Canada and heavy bituminous oils extracted from oil sands.
Other sources of heavy oils can be such materials as atmospheric tar bottoms
products, vacuum tar bottoms products, heavy cycle oils, shale oils, coal-
derived
liquids, crude oil residua, topped crude oils, and combinations thereof
[003] Efficient processing and viscosity reduction of heavy hydrocarbon oils
is desirable for the production, transport and refining operations of crude
oil.
Commonly practiced methods include diluting the crude oil with gas condensate
and
emulsification with caustic and water, in addition to thermally treating crude
oil and
combining crude oil with hydrogen gas. Limitations or disadvantages of these
methods can include long reaction times that result in an increase in the
generation of
undesirable waste materials, specifically pitch, coke, and olefins. These
materials
create significant disposal challenges for the processing facility, and, in
addition, lead
to a reduction in the efficiency of the facility. Thus, there is a need for
novel
technologies for treating heavy oils and bitumen to yield lighter and less
viscous
resources.
SUMMARY
[004] A process for treating a hydrocarbon oil including providing a flow-
through, hydrodynamic cavitation apparatus having a local constriction. The
hydrocarbon oil is passed through the local constriction of the flow-through,
hydrodynamic cavitation apparatus to form cavitation bubbles. No substances
that
1
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
are not a hydrocarbon oil are passed through the cavitation apparatus with the
hydrocarbon oil, either in a mixture with the hydrocarbon oil or separately.
The
cavitation bubbles are collapsed under static pressure to treat the
hydrocarbon oil.
The treated hydrocarbon oil is extracted or removed from the cavitation
apparatus.
The treated hydrocarbon oil has an increased API gravity compared to the
untreated
hydrocarbon oil prior to passing it through the cavitation apparatus.
[005] A process for treating a hydrocarbon oil including providing a flow-
through, hydrodynamic cavitation apparatus having a local constriction. The
hydrocarbon oil is passed through the local constriction of the flow-through,
hydrodynamic cavitation apparatus to form cavitation bubbles. No substances
that
are not a hydrocarbon oil are passed through the cavitation apparatus with the
hydrocarbon oil, either in a mixture with the hydrocarbon oil or separately.
The
cavitation bubbles are collapsed under static pressure to treat the
hydrocarbon oil.
The treated hydrocarbon oil is extracted or removed from the cavitation
apparatus.
The treated hydrocarbon oil has a reduced viscosity compared to the untreated
hydrocarbon oil prior to passing it through the cavitation apparatus.
[006] A process for reducing the viscosity of a heavy hydrocarbon oil
including providing a flow-through, hydrodynamic cavitation apparatus having a
local constriction. A preheated fluid being essentially heavy hydrocarbon oil,
substantially free or free of non-heavy hydrocarbon oil substances, at a
temperature
of at least 320 C, is passed through the local constriction of the flow-
through,
hydrodynamic cavitation apparatus to form cavitation bubbles. The cavitation
bubbles are collapsed under static pressure to treat the fluid. The treated
fluid is
extracted from the cavitation apparatus wherein the treated fluid has a
viscosity of at
least 80 percent less than the viscosity of the fluid prior to passing through
the
cavitation apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[007] FIG. 1 shows a flow diagram of a process for treating hydrocarbon oil.
[008] FIG. 2 shows a cross section view of a cavitation apparatus.
[009] FIG. 3 shows a cross section view of a cavitation apparatus.
[0010] FIG. 4 shows a cross section view of a cavitation apparatus.
2
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
DETAILED DESCRIPTION
[0011] Herein, when a range such as 5-25 (or 5 to 25) is given, this means
preferably at least 5 and, separately and independently, preferably not more
than or
less than 25. In an example, such a range defines independently not less than
5, and
separately and independently, not less than 25.
[0012] Processes for upgrading hydrocarbon oil are described herein. The
processes relate to treating hydrocarbon oil, and preferably heavy hydrocarbon
oil, by
subjecting the hydrocarbon oil to hydrodynamic cavitation to induce
destructing
forces that can reduce the viscosity and/or increase the API gravity of the
hydrocarbon oil. Treatment of hydrocarbon oil, as used herein, relates to the
hydrodynamic cavitation of the hydrocarbon oil such that its viscosity is
reduced
and/or API gravity is increased. Hydrodynamic cavitation as described below
yields
high pressure, such as above 600 psi, and high temperature, such as above 380
C,
processing conditions that are desirable for effectively treating hydrocarbon
oil.
[0013] In general, cavitation can be described as the generation, subsequent
growth and collapse of cavitation bubbles. During the collapse of the
cavitation
bubbles, high-localized pressures and temperatures are achieved, with some
estimations of 5000 C and pressure of approximately 500 kg/cm2 (K. S.
Suslick,
Science, Vol. 247, 23 Mar. 1990, pgs. 1439-1445). High temperatures and
pressures
can create destructive forces which may not be possible under ordinary
conditions,
such as standard temperature and pressure, STP. Thus, it is possible to
provide
physical changes to a substance under the influence of cavitation. Without
intending
to be bound by any one theory, it is believed that the applying cavitational
energy
and quickly achieving significant physical characteristic changes, such as
within
seconds or less, may reduce the cost of treating hydrocarbon oils.
[0014] The cavitation treatment of the hydrocarbon oil can create treated
hydrocarbon oil having improved and stable physical characteristics, such as
reduced
viscosity and increased API gravity. The treated and stable hydrocarbon oil
having
increased API gravity and/or reduced viscosity preferably retains the upgraded
physical properties over time or permanently such that the improved API
gravity
and/or viscosity parameters do not return to original values as measured in
the pre-
processed or untreated hydrocarbon oil.
3
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
[0015] The hydrocarbon oil can be heavy hydrocarbon oil having high
viscosity and/or low API gravity, which can cause the oil to be difficult to
pump and
process. A heavy hydrocarbon oil includes oil having a high viscosity and/or
an API
gravity less than about 23 degree, such as that found in oils extracted from
oil sands,
or materials such as atmospheric tar bottoms products, vacuum tar bottoms
products,
heavy cycle oils, shale oils, coal-derived liquids, crude oil residue, topped
crude oils
and the like.
[0016] In one embodiment, provided is a process for treating fluid being
hydrocarbon oil, and preferably heavy hydrocarbon oil, by subjecting it to
hydrodynamic cavitation to reduce the viscosity and/or increase the API
gravity of
the hydrocarbon oil. Preferably, the hydrocarbon oil is treated with
hydrodynamic
cavitation without mixing the hydrocarbon oil with a non-hydrocarbon oil
substance
such that the hydrocarbon oil is treated in absence of a non-hydrocarbon oil
substance or is substantially free of non-hydrocarbon oil substances, for
example,
less than 1 weight percent, more preferably less than 0.5 weight percent and
more
preferably less than 0.1 weight percent of a non-hydrocarbon oil substance as
measured by weight of the hydrocarbon oil to be treated. For example, non-
hydrocarbon oil substances can include, but are not limited to, gases, such as
hydrogen gas, catalysts, caustic, organic materials, organic solvents, such as
pentane,
liquefied petroleum gases, alcohols, such as ethanol and methanol, ethers,
water or
steam, and mixtures thereof Although hydrocarbon oil inherently contains a
mixture
of materials, for purposes herein, hydrocarbon oil is not mixed with non-
hydrocarbon
oil substances or individual components present in the hydrocarbon oil prior
to
processing through the cavitation apparatus.
[0017] In another embodiment, the process for treating fluid being
hydrocarbon oil, and preferably heavy hydrocarbon oil, by subjecting it to
hydrodynamic cavitation to reduce the viscosity and/or increase the API
gravity of
the hydrocarbon oil is completed in the absence of other cavitation
techniques, such
as the use of ultrasonic or acoustic energy or sound waves, for example from
an
ultrasonic horn, to induce cavitation. Thus, the flow-through, hydrodynamic
cavitation apparatus can exclude external devices for emitting ultrasonic or
acoustic
cavitation.
[0018] In another embodiment, the process for treating fluid being
hydrocarbon oil, and preferably heavy hydrocarbon oil, by subjecting it to
4
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
hydrodynamic cavitation to reduce the viscosity and/or increase the API
gravity of
the hydrocarbon oil is completed in the absence of other cavitation
techniques, such
as dynamic devices that produce hydrodynamic cavitation. Dynamic devices can
include moving or rotating parts that promote or induce cavitation as a
function of
shearing forces caused by moving mechanical or magnetic parts of such devices.
The flow-through, hydrodynamic cavitation apparatus is preferably a static
cavitation
apparatus containing no moving parts such that cavitation is induced by
forcing or
actively passing fluid through the static cavitation apparatus to produce a
cavitation
zone at or near a stationary local constriction in the apparatus, such as an
orifice. As
discussed in the Examples below, cavitational energy can be created by passing
the
fluid through a static cavitation reactor having one or more orifices, either
in a single
pass or cycle or multiple passes as desired.
[0019] Turning to the figures, FIG. 1 shows a schematic flow diagram of a
process for treating hydrocarbon oil. Hydrocarbon oil feedstock is provided in
storage vessel 1. The storage vessel 1 can be an atmospheric or pressurized
tank, and
further include a heating means, such as a heating jacket, for heating the
hydrocarbon
oil feedstock prior to treatment. Hydrocarbon oil feedstock can be dense (low
API
gravity, such as in the range of 10 to 23 degree) and have a high viscosity,
such as
above 200 cSt at a temperature of 50 C, which can make the hydrocarbon oil
difficult to pump. Preheating the hydrocarbon oil feedstock can increase
flowability
and ease pumping for purposes of processing. The hydrocarbon oil feedstock 2
can
be drawn from storage vessel 1 to feed pump 3 for transferring the pumped
hydrocarbon oil 4 to heat exchanger 10.
[0020] The hydrocarbon oil 4 stream can be heated to a temperature in the
range of 300 to 500 C by any conventional heating method, such as by one or
a
combination of heating components. As shown, the hydrocarbon oil 4 stream can
be
heated by passing through heat exchanger 10. The preheated hydrocarbon oil 11
can
be further heated in a heat exchanger 12, such as an oven. The heated
hydrocarbon
oil 13 can be fed to a flow-through cavitation apparatus 14 for inducing
cavitation
treatment of the hydrocarbon oil 13. The flow-through cavitation apparatus 14
preferably includes at least one local constriction, such as an orifice, one
or more
baffles, or nozzle, for statically generating a hydrodynamic cavitation zone.
The
flow-through cavitation apparatus 14 can be as described in U.S. Pat. Nos.
5,810,052;
5,931,771; 5,937,906; 5,971,601; 6,012,492; 6,502,979; 6,802,639 and
6,857,774.
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
[0021] The flow-through cavitation apparatus 14 can create a hydrodynamic
cavitation zone containing cavitation bubbles. The cavitation bubbles are
generated
by passing the hydrocarbon oil 13 through the local constriction of the
cavitation
apparatus 14 at an inlet pressure of at least 300, 500, 800, 1000, 1300, 1500,
1800,
2000, 2300, 2600 or 2900 psi. The pressure drop across the local constriction
can be
at least 300, 500, 800, 1000, 1200, 1500, 1800, 2000, 2200 or 2500 psi. The
cavitation bubbles can be maintained in the hydrodynamic cavitation zone for
less
than 0.1, 0.05, 0.01, 0.005, 0.0025 or 0.001 second. The cavitation bubbles
are
collapsed under static pressure downstream of the local constriction of the
cavitation
apparatus 14. The collapsing of the cavitation bubbles induces treatment of
the
hydrocarbon oil thereby increasing the API gravity of the hydrocarbon oil
and/or
reducing the viscosity of the hydrocarbon oil, as compared to values measured
prior
to passing the untreated hydrocarbon oil through the cavitation apparatus. The
static
pressure for collapsing the cavitation bubbles is at least 150 psi, and
preferably in the
range of 150-600, 150-400 or 200-400 psi.
[0022] The treated hydrocarbon oil 15 downstream of the flow-through,
hydrodynamic cavitation apparatus 14 can have an API gravity increase (i.e.
lighter)
of greater than 20, 30, 40, 50, 60, 70, 80, 85, 90, 95 or 98 percent. For
instance, the
API gravity of the treated hydrocarbon oil 15 can be 1, 1.5, 2, 2.5, 3, 4, 5,
6, 7, 8, 9 or
degree higher than the untreated hydrocarbon oil 2. The treated hydrocarbon
oil
can have a viscosity reduction of at least 30, 40, 50, 60, 70, 80, 85, 90, 95
or 99.5
percent. For instance, the viscosity of the treated hydrocarbon oil 15 can be
100, 200,
500, 700, 800, 900, 1,000, 5,000, 10,000, 15,000, 20,000, 25,000 or 30,000
centiStokes (cSt) lower than the untreated hydrocarbon oil 2.
[0023] The treated hydrocarbon oil 15 can be used as a heating medium for
pre-heating the pre-processed or untreated hydrocarbon oil stream 9. For
example,
the treated hydrocarbon oil 15, which can be at a temperature of 300 to 500
C, 320
to 480 C, or 400 to 460 C, can be passed through heat exchanger 10 before
being
cooled later to result in an upgraded hydrocarbon oil 16 having improved
viscosity
and/or API gravity characteristics. The heat exchange from the treated
hydrocarbon
oil 15 to the pre-processed hydrocarbon oil 9 also functions to cool the
treated
hydrocarbon oil 15.
[0024] FIG. 2 shows a flow-through, hydrodynamic cavitation apparatus 14
having a local constriction 21, such as an orifice 22, for statically treating
6
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
hydrocarbon oil 13 via hydrodynamic cavitation. The orifice 22 can be any
shape, for
example, cylindrical, conical, oval, right-angled, square, etc. Depending on
the size
and shape of the orifice 22, the shape of the cavitation zone flowing at or
downstream from the local constriction 21 can be controlled. The orifice 22
can have
any diameter, D2, for example, the diameter can be greater than 0.1, 0.2, 0.3,
0.4, 0.6,
0.8, 1, 2, 5, 10 or 20 mm. In one example, the orifice 22 diameter can be
about 0.3
mm to about 1 mm.
[0025] Alternatively, the local constriction 21 can include baffles, nozzles
and the like. Although not shown, the flow-through channel 20, such as a pipe
or
tube, can have two or more local constrictions in series, such as a first
local
constriction having one orifice of a desired diameter and a second local
constriction
having one orifice of a desired diameter. The diameters of the first and
second
orifices can be the same or may vary.
[0026] As shown, the first chamber 23 has a static pressure Pi and the second
chamber 24 has a static pressure P2. Hydrocarbon oil flow 13 into the
apparatus 14
can be provided with the aid of fluid pumping devices as known in the art,
such as a
pump, centrifugal pump, positive-displacement pump or diaphragm pump. An
auxiliary pump can provide flow under a static pressure Pi, or the processing
pressure, to the first chamber 23. The processing pressure is preferably at
least 200,
500, 700, 1,000, 1,400, 1,800, 2,200, 2,500 or 2,900 psi. The processing
pressure is
reduced as the hydrocarbon oil 13 passes through the flow-through channel 20
and
orifice 22. Maintaining a pressure differential across the orifice 22 allows
control of
the cavitation intensity in the hydrodynamic cavitation zone in the flow-
through
channel 20 near or downstream of the local constriction 21. The pressure
differential
across the orifice 22 is preferably at least 300, 500, 800, 1000, 1200, 1500,
1800,
2000, 2200 or 2500 psi. The velocity of the hydrocarbon oil 13 through the
orifice
22 in the apparatus 14 is preferably at least 1, 5, 10, 15, 20, 25, 30, 40,
50, 60 or 70
meters per second (m/s).
[0027] The length (1) of the orifice 22 in the local constriction 21 is
selected
to adjust the residence time of the cavitation bubbles in the orifice 22
and/or the
second chamber 24 housing the cavitation zone to be less than 0.1, 0.05, 0.01,
0.005,
0.0025 or 0.001 second. Downstream 25 of the orifice 22, a valve 26 can be
used to
adjust the desired static pressure P2 for collapsing the cavitation bubbles
downstream
of the local constriction of the cavitation apparatus 14 wherein the valve 26
can
7
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
provide controlled flow cavitation. The treated hydrocarbon oil 30 exits or is
extracted from the valve 26 before being subsequently cooled.
[0028] FIG. 3 illustrates a flow-through cavitation apparatus 14 having a
sharp-edged orifice 33 for generating a hydrodynamic cavitation zone for
treating
hydrocarbon oil 13. The sharp-edged orifice 33 has a diameter, D2, in the
range of 0.2
to 100 mm, which faces upstream towards chamber 34. The orifice 33 expands
along
the length of the local constriction 32 and towards the second chamber 35 at
an angle
in the range of 10 to 60 degrees. The flow-through channel 36 has an inlet
diameter,
Di, in the range of 0.25 to 80 inches. The local constriction 32 divides the
flow-
through channel 36 into a first chamber 34 having static pressure Pi and a
second
chamber 35 having static pressure P2. Preferably, static pressure P2 induces
the
collapse of cavitation bubbles and is greater than 150 psi, and more
preferably
greater than 300 psi. In operation, hydrocarbon oil 13 passes through the flow-
through channel 36 and through the local flow constriction 32 to generate
cavitation
bubbles that are collapsed under static pressure P2 in the second chamber 35
to
produce treated hydrocarbon oil 30 that is extracted from the second chamber
35
before being subsequently cooled.
[0029] Although not shown, the flow-through channel 36 can have additional
local constrictions or control measures, such as a valve, downstream of the
first local
constriction 32 in order to alter the cavitation conditions and static
pressure P2 and
provide for a controlled flow. The additional local constriction can be
adjustable, for
example a valve, or non-adjustable, for example an orifice.
[0030] In another embodiment, FIG. 4 provides a cross section view of a
flow-through, hydrodynamic cavitation apparatus 14. A bluff body 43 is
positioned
in the flow-through channel 40 to create local constrictions, wherein two
local
constrictions are created in parallel to one another, each local constriction
is
positioned between the inner wall of the flow-through channel 40 and the top
or
bottom surface of the bluff body 43, 44. The local constrictions divide the
flow-
through channel 40 into two chambers, a first chamber 41 having static
pressure and
a second cavitation chamber 42 having static pressure. The second chamber 42
houses the hydrodynamic cavitation zone as discussed above. In operation,
hydrocarbon oil 13 passes through the flow-through channel 40 and around bluff
body 43 to generate cavitation bubbles in a cavitation zone downstream of the
local
8
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
constriction that are subsequently collapsed under static pressure in the
second
cavitation chamber 42.
[0031] Although not shown, the flow-through channel 40 can have two or
more bluff bodies or local constrictions, such as an orifice, in series. For
example, a
first cone-shaped bluff body having a desired diameter and a second cone-
shaped
bluff body having a desired diameter can be arranged in series. The diameters
of the
first and second bluff bodies can be the same or may vary.
[0032] In order to promote a further understanding of the invention, the
following examples are provided. These examples are shown by way of
illustration
and not limitation. The hydrocarbon oil treatment process of Examples 1
through 5
was carried out in a flow-through cavitation apparatus substantially similar
to the
cavitation apparatus 14 as shown in FIG. 2 herein. The cavitation apparatus
included
a single orifice having a diameter in the range of 0.012 inches (0.3 mm) to
0.014
inches (0.36 mm) and was capable of operating at a pressure of up to 3,000 psi
with a
nominal flow rate of up to 300 mL/min.
[0033] Example 1
[0034] A feed stock of Canadian heavy crude oil was used. The Canadian
heavy crude oil had an average API gravity of 12.0 degree, and a kinematic
viscosity
of 999.7 cSt at a temperature of 50 C.
[0035] The Canadian heavy crude oil was passed through a pipe at a
processing pressure of 1,950 psi and at a temperature of 460 C by a high
pressure
pump. The heated hydrocarbon oil was pumped through a cavitation apparatus
having a single orifice of diameter 0.3 mm. The pressure drop across the
orifice was
sufficient to generate a hydrodynamic cavitation zone containing cavitation
bubbles
that were collapsed downstream of the orifice under a static pressure of 400
psi. The
pressure drop across the orifice was about 1,550 psi. The treated hydrocarbon
oil
(i.e. downstream of the hydrodynamic cavitation zone) was passed through a
heat
exchanger and the temperature of the treated hydrocarbon oil was reduced to 40
C.
[0036] The treated hydrocarbon oil had an API gravity of 14.5 degree and a
kinematic viscosity of 68.6 cSt at 50 C. The treated hydrocarbon oil had an
increase
in API gravity of about 21 percent and a reduction in viscosity of about 93
percent.
The increased API gravity and reduced viscosity of the treated hydrocarbon oil
did
not reverse and return to original values.
[0037] Example 2
9
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
[0038] A feed stock of Canadian heavy crude oil was used. The Canadian
heavy crude oil had an average API gravity of 10.3 degree, and a kinematic
viscosity
of 1077.0 cSt at a temperature of 50 C.
[0039] The Canadian heavy crude oil was passed through a pipe at a
processing pressure of 1,800 psi and at a temperature of 420 C by a high
pressure
pump. The heated hydrocarbon oil was pumped through a cavitation apparatus
having a single orifice of diameter 0.3 mm. The pressure drop across the
orifice was
sufficient to generate a hydrodynamic cavitation zone containing cavitation
bubbles
that were collapsed downstream of the orifice under a static pressure of 360
psi. The
pressure drop across the orifice was about 1,440 psi. The treated hydrocarbon
oil
(i.e. downstream of the hydrodynamic cavitation zone) was passed through a
heat
exchanger and the temperature of the treated hydrocarbon oil was reduced to 40
C.
[0040] The treated hydrocarbon oil had an API gravity of 15.3 degree and a
kinematic viscosity of 130.5 cSt at 50 C. The treated hydrocarbon oil had an
increase in API gravity of about 49 percent and a reduction in viscosity of
about 88
percent. The increased API gravity and reduced viscosity of the treated
hydrocarbon
oil did not reverse and return to original values.
[0041] Example 3
[0042] A feed stock of Canadian heavy crude oil was used. The Canadian
heavy crude oil had an average API gravity of 10.7 degree, and a kinematic
viscosity
of 1031.0 cSt at a temperature of 50 C.
[0043] The Canadian heavy crude oil was passed through a pipe at a
processing pressure of 2,839 psi and at a temperature of 328 C by a high
pressure
pump. The heated hydrocarbon oil was pumped through a cavitation apparatus
having a single orifice of diameter 0.36 mm. The pressure drop across the
orifice was
sufficient to generate a hydrodynamic cavitation zone containing cavitation
bubbles
that were collapsed downstream of the orifice under a static pressure of 308
psi. The
pressure drop across the orifice was about 2,531 psi. The treated hydrocarbon
oil
(i.e. downstream of the hydrodynamic cavitation zone) was passed through a
heat
exchanger and the temperature of the treated hydrocarbon oil was reduced to 40
C.
[0044] The treated hydrocarbon oil had an API gravity of 18.1 degree and a
kinematic viscosity of 49.3 cSt at 50 C. The treated hydrocarbon oil had an
increase
in API gravity of about 69 percent and a reduction in viscosity of about 95
percent.
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
The increased API gravity and reduced viscosity of the treated hydrocarbon oil
did
not reverse and return to original values.
[0045] Example 4
[0046] A feed stock of United States heavy crude oil was used. The United
States heavy crude oil had an average API gravity of 14.8 degree, and a
kinematic
viscosity of 262.4 cSt at a temperature of 50 C.
[0047] The United States heavy crude oil was passed through a pipe at a
processing pressure of 2,450 psi and at a temperature of 400 C by a high
pressure
pump. The heated hydrocarbon oil was pumped through a cavitation apparatus
having a single orifice of diameter 0.3 mm. The pressure drop across the
orifice was
sufficient to generate a hydrodynamic cavitation zone containing cavitation
bubbles
that were collapsed downstream of the orifice under a static pressure of 300
psi. The
pressure drop across the orifice was about 2,150 psi. The treated hydrocarbon
oil
(i.e. downstream of the hydrodynamic cavitation zone) was passed through a
heat
exchanger and the temperature of the treated hydrocarbon oil was reduced to 40
C.
[0048] The treated hydrocarbon oil had an API gravity of 20.9 degree and a
kinematic viscosity of 8.4 cSt at 50 C. The treated hydrocarbon oil had an
increase
in API gravity of about 41 percent and a reduction in viscosity of about 97
percent.
The increased API gravity and reduced viscosity of the treated hydrocarbon oil
did
not reverse and return to original values.
[0049] Example 5
[0050] A feed stock of Newalta heavy crude oil was used. The Newalta heavy
crude oil had an average API gravity of 12.4 degree, and a kinematic viscosity
of
714.1 cSt at a temperature of 50 C.
[0051] The Newalta heavy crude oil was passed through a pipe at a
processing pressure of 1,928 psi and at a temperature of 482 C by a high
pressure
pump. The heated hydrocarbon oil was pumped through a cavitation apparatus
having a single orifice of diameter 0.36 mm. The pressure drop across the
orifice was
sufficient to generate a hydrodynamic cavitation zone containing cavitation
bubbles
that were collapsed downstream of the orifice under a static pressure of 178
psi. The
pressure drop across the orifice was about 1,750 psi. The treated hydrocarbon
oil
(i.e. downstream of the hydrodynamic cavitation zone) was passed through a
heat
exchanger and the temperature of the treated hydrocarbon oil was reduced to 40
C.
11
CA 02848468 2014-03-12
WO 2013/039759
PCT/US2012/053950
[0052] The treated hydrocarbon oil had an API gravity of 20.7 degree and a
kinematic viscosity of 4.4 cSt at 50 C. The treated hydrocarbon oil had an
increase
in API gravity of about 67 percent and a reduction in viscosity of about 99
percent.
The increased API gravity and reduced viscosity of the treated hydrocarbon oil
did
not reverse and return to original values.
[0053] As can be seen from the Examples, a single pass or cycle through the
flow-through, hydrodynamic cavitation apparatus having a single local
constriction,
such as an orifice, can increase the API gravity of the treated hydrocarbon
oil as
compared to the pre-processed or untreated hydrocarbon oil prior to being
passed
through the cavitation apparatus by 2.5 to 8.3 degree, or 21 to 69 percent.
Thus, as
shown, a pressure drop of at least 1,400 psi can result in an increase of API
gravity of
at least 2.5 degree. Operating temperatures of at least 300 C, and more
preferably
over 400 C, were utilized to achieve the reported API gravity increases.
[0054] The Examples further show that the treated hydrocarbon oil, as
compared to the pre-processed hydrocarbon oil prior to being passed through
the
cavitation apparatus, can have a reduced viscosity in the range of 254 to 982
cSt at a
temperature of 50 C, or 88 to 99 percent. The increase in API gravity and
reduction
in viscosity occurred over a pressure drop range of 1,440 to 2,531 psi.
Pressure
drops of at least 1,500 psi over the local constriction resulted in viscosity
reduction of
at least 93% and a pressure drop of at least 1,750 psi resulted in viscosity
reduction
of at least 95%. Operating temperatures of at least 300 C, and more
preferably over
400 C, were utilized to achieve the reported viscosity reductions.
[0055] It will be understood that this invention is not limited to the above-
described embodiments. Those skilled in the art having the benefit of the
teachings
of the present invention as hereinabove set forth, can effect numerous
modifications
thereto. These modifications are to be construed as being encompassed with the
scope of the present invention as set forth in the appended claims.
12
