Note: Descriptions are shown in the official language in which they were submitted.
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 A PROCESS FOR PRODUCING TAILORED SYNTHETIC CRUDE OIL
2 THAT OPTIMIZE. CRUDE SLATES IN TARGET REFINERIES:
3 FIELD OF THE INVENTION
4 The present invention relates to a continuous or batch process wherein a
heavy
oil feedstock upgrader produces a synthetic crude oil which is custom tailored
to fill
6 out a refinery's crude slate.
7 BACKGROUND OF THE INVENTION
8 Global energy usage continues to rise with no sign of abatement,
creating a
9 growing demand for oil resources: Light, sweet crude oil production is
not increasing
enough to meet this. growing demand. Additionally, the reserves of light,
sweet crude
11 oil are being depleted more rapidly than new reserves are being found.
To fill this
12 gap, larger quantities of heavy oil feedstocks such as heavy crude oils
or extra heavy
13 crude oils derived from various carbonaceous resources are being brought
on Stream.
14 The.cost of development of these heavy crude, oil resources has been
decreasing over
the last several dedades,maldng them more economical to recover.
16 Heavy crudes often require some processing to reduce their viscosity and
to
17 make them pumpable. Several processes which may beused for this purpose
include
18 partial upgrading by hydroprocessing, by coking.or by blending the heavy
crude With
19 light hydrocarbOns.:Additives.may also be used. Another alternative for
handling
.heavy crude is to form an oil-in-water emulsion, Optionally With the addition
Of
.21 additives to reduce the..crude's.viscosity.. All of these. processes
create a pumpable
22 generic type syncrude suitable for refinery processing. However, the
economics of
23 processing these pturnpable generic type syncrudes are prohibitively
expensive,
24 because of the low.conversion rates of the heavy crude oil resources,
U.S. Patent 3,369,992 discloses a distillate low pour point synthetic Crude
oil
26 produced from a virgin distillate and a reduced crude from a high wax
content and
27 high pour point crude This Synthetic crude is formed by Mixing the
virgin distillate
- I -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
with a fraction obtained by coking the reduced crude. The coker overhead
volatile
2 product is fractionated into a heavy stream for recycle to the coker and
a distillate
3 fraction which is recovered as a low pour point synthetic crude.
4 U.S. Patent 4,454,023 discloses a process, including visbreaking,
distillation,
and solvent extraction for rendering a heavy viscous crude purnpable.
6 U.S. Patent 5.,233,109 discloses a synthetic crude produced by
catalytically
7 cracking a biomass material comprising a plant oil and/or an animal oil
and/or a
8 rubber material.
U.S. Patent 6.016,868 discloses an integrated process for treating production
fluids to form a synthetic crude oil. The production fluids are recovered from
the
11 application of in situ hydrovisbreaking of heavy crudes and natural
bitumen deposited
12 in subsurface formations.
13 U.S. Patent Application Publication 2004/0164001 Al discloses a business
14 process that monetizes bitumen reserves utilizing proven refining
processes to
ultimately produce high quality refined oil products.
16 Additional disclosures relating to the preparation of a syncrude are
taught in
17 U.S. Patents 5,968,991; 5.945A59; 5,856,261; 5,856,260; 5,863,856 and
5,292,989.
18 While some processes have been proposed to reduce the viscosity via
crude,
19 none have been offered for producing a synthetic. crude which is
tailored for the
current needs of a particular refinery. Furthermore, no process has been
described for
21 producing a synthetic crude which comprises vacuum gas oil or lighter
fractions.
-2-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 SUMMARY OF THE INVENTION
2 The present invention is directed to a process for preparing a syncrude.
The
3 present invention is also directed to a process for tailoring a syncrude
such that it has
4 optimum properties with respect to the requirements for producing fuels
and/or
lubricant base oils in a particular refinery. The present invention is also
directed to a
6 process which upgrades a heavy crude oil to produce a multiplicity of
syncrudes, each
7 tailored for one of a multiplicity of refineries.
8 The feedstock to the process is a heavy oil feedstock. The synthetic
crude
9 (alternatively "syncrude") which is made in the present process is a
partially upgraded
crude feedstock, having a lower sulfur content and a lower metals content than
the
11 heavy oil feedstock from which it is made. In a Thither embodiment, the
syncrude is
12 more easily processed in a conventional refinery than the heavy oil
feedstock from
13 which it is made. In a further embodiment, the syncrude boils within a
range of
14 temperatures which is lower than the boiling range of the heavy oil
feedstock from
which it is made.
16 At least in part, the present invention is based on the realization that
there is a
17 particular crude or range or crudes with properties which are ideal for
a particular
18 refinery. Thus, a target refinery identifies the properties of a
tailored feedstock which,
19 when processed in the refinery, meets select targets for overall
operation and the
distribution and quality of the product slate. Conventionally, a refinery must
process a
21 number of crudes, some of which may have widely differing properties.
Though each
22 refinery tries to select crudes which best meet its particular
requirements, making
23 such .a selection often has undesirable cost implications. At best, the
refinery will
24 attempt to purchase a crude slate that meets some of its requirements.
In contrast, the product of the present process is a tailored synthetic crude,
26 with properties which are tailored to meet the requirements of a
particular target
27 refinery. The crude is further a synthetic crude, produced by upgrading
a heavy oil
28 feedstock. The upgrading conditions used in the upgrading step to
produce the
29 tailored crude is selected on the basis of a relining data set from the
target refinery
- 3 -
CA 02680878 2014-01-15
1 that characterizes the tailored synthetic etude and of a feedstock data
set that
2 characterizes a heavy oil feedstock,
3 Accordingly, the present invention provides an integrated integrated
process
4 for upgrading a heavy oil feedstock, the process comprising: (a)
establishing a
communication link between an upgrading facility and a target refinery; (b)
acquiring
6 a refining data set from the target refinery that characterizes a
tailored synthetic crude;
7 (c) generating an upgrading data set from the upgrading facility that
characterizes a
8 heavy oil feedstock; (d) using the refining data set from the target
refinery and the
9 upgrading data. set from the upgrading facility to generate a dataset of
select
10.upgrading process conditions; (e) hydroproeessing the a heavy oil
feedstock, at the
11 select upgrading process conditions, within the upgrading facility and
recovering a
12 tailored synthetic crude; and (f) transporting the tailored synthetic
crude to the target
13 refinery,
14 In one embodiment, the upgrading step is a hydroprocessing step,
comprising
contacting the heavy oil feedstock with hydrogen in the presence of an
unsupported
16 slurry catalyst, In a further embodiment, the unsupported slurry
catalyst comprises
17 molybdenum sulfide. In yet a further embodiment, the unsupported slurry
catalyst is
18 prepared by: (a) mixing a Group VI B metal oxide and aqueous ammonia to
form a
19 Group VI metal compound aqueous mixture; (b) sulfiding, in an first
reaction zone,
the aqueous mixture with a gas comprising hydrogen sulfide to a dosage greater
than
21 8 SCF of hydrogen sulfide per pound of Group ATIB metal to form a
slurry; (c)
22 promoting the slurry with a Group VIII metal; (d) mixing the promoted
slurry with a
23 first hydrocarbon oil having a viscosity of at least 2 cSt at 212cF to
form a reaction
24 mixture; (e) combining the reaction mixture with hydrogen gas and a
second
hydrocarbon oil in a second reaction zone to form an active catalyst
composition, the
26 second hydrocarbon oil having a boiling point, in the range from 50 F to
300 F and
27 further having a lower viscosity than the first hydrocarbon oil. This
embodiment is
28 further described in U.S. Serial Numbers 10/938202, 10/938269,
10/938003,
29 101938438, I0/938200
- 4 -
CA 02680878 2014-01-15
1 In accordance with another aspect, there is provided an integrated
process for
2 upgrading a heavy oil feedstock, comprising:
3 a) establishing a communication link between an upgrading facility and a
4 target refinery;
b) acquiring a refining data set from the target refinery that characterizes a
6 tailored synthetic crude having a 95% boiling point as determined by ASTM
D1160
7 of less than 1000 F and API gravity of greater than 10;
8 c) generating a feedstock data set from the upgrading facility that
characterizes
9 a heavy oil feedstock having a 95% boiling point as determined by ASTM
D1160 of
greater than 1000 F;
11 d) using the refining data set from the target refinery and the
feedstock data set
12 from the upgrading facility to generate an upgrading dataset of select
upgrading
13 process conditions;
14 e) upgrading the heavy oil feedstock at the select upgrading process
conditions
within the upgrading facility and recovering a tailored synthetic crude,
wherein the
16 upgrading comprises contacting the heavy oil feedstock with hydrogen in
the presence
17 of an active unsupported slurry catalyst wherein the active unsupported
slurry catalyst
18 in oil is a catalyst composition prepared by:
19 a) mixing a Group VI B metal oxide and aqueous ammonia to form a
Group VI metal compound aqueous mixture;
21 b) sulfiding, in a first reaction zone, the aqueous mixture with a
gas
22 comprising hydrogen sulfide to a dosage greater than 8 SCF of hydrogen
23 sulfide per pound of Group VIB metal to form a slurry;
24 c) promoting the slurry with a Group VIII metal;
d) mixing the promoted slurry with a first hydrocarbon oil having a
26 viscosity of at least 2 cSt at 212 F to form a reaction mixture;
27 e) combining the reaction mixture with hydrogen gas and a second
28 hydrocarbon oil in a second reaction zone to form an active catalyst
29 composition, the second hydrocarbon oil having a boiling point in the
range
from 50 F. to 300 F and further having a lower viscosity than the first
31 hydrocarbon oil; and
32 I) transporting the tailored synthetic crude to the target
refinery.
- 4a -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 BRIEF DESCRIPTION OF THE DRAWINGS
2 Figure 1 illustrates the preparation of an unsupported slurry catalyst.
3 Figure 2 illustrates upgrading employing the unsupported slurry
catalyst.
4 Figure 3 illustrates an heavy crude oil upgrading facility producing two
distinct custom tailored syncrudes for two target refineries, each
communicating their
6 own optimum "synthetic trim crude" requirements and "willing-to-pay"
price.
7 DETAILED DESCRIPTION OF THE INVENTION
8 This invention is directed to a process wherein a heavy oil feedstock
upgrader
9 creates a custom tailored synthetic crude feedstock based upon data
communicated
from a target refinery and data gathered from the heavy oil feedstock
upgrader. The
11 data from the target refinery represents refining process data and
linear program
12 modeling along with analysis by a refining planner to calculate the
optimum
13 "synthetic trim crude" that will improve, and ideally optimize, the
effective use of the
14 target refinery's capacity and equipment. Economic information,
including a 'willing-
to-pay" price is calculated for a specified volume of tailored synthetic
crude. This
16 information is then communicated to the heavy oil feedstock upgrader.
The heavy oil
17 feedstock upgrader will use the refining data plus the data that
characterizes the heavy
18 oil feedstock resource to model and analyze all the data sets. The
resulting analysis
19 informs the heavy oil feedstock planner the appropriate upgrading
operating
conditions needed to produce the tailored crude for the target refinery. The
process
21 will further allow a heavy oil feedstock upgrader to supply each of
multiple refineries
22 with an individual optimized tailored syncrude that meets the current
crude feedstock
23 needs for that refinery.
24 'Heavy Oil Feedstock
In embodiments of the invention, the heavy oil feedstock may be a raw stock
26 such as a crude that is upgraded according to the present process. The
feedstock may
27 be hydroprocessed prior to upgrading or it may be treated to remove
contaminants,
- 5 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 e.g. salts and water, prior to upgrading. The feedstock may be a residuum
fraction
2 from distillation. It may be one or more products from a separation
process, or it may
3 be the product of a pyrolysis or liquefaction process. It may be the
product from a size
4 reduction process, e.g. grinding, or it may the product from a prior
processing step.
The heavy oil feedstock which is the feed to the process is a carbonaceous oil
6 derived from at least one of the following sources: tar sands; bitumen;
coal; lignite;
7 peat; oil shale; crude oils; synthetic oils such as from a Fischer-
Tropsch process;
6 recycled oil wastes and polymers; and residuum bottom process stream
oils.
9 Typically, the heavy oil feedstock has a API gravity that ranges from 12
to less than 0,
a viscosity greater than 5000 cp at 100 F, and with significantly high
concentrations
11 of nitrogen, sulfur, metal contaminants, and asphaltenes. Furthermore,
the heavy oil
12 feedstock has a 95 percent normal boiling point, as determined by ASTM
D1160 of
13 greater than I000 F. Heavy oil feedstocks with at least 50 volume
percent boiling
14 above 1000 F and even at least 75 volume percent boiling above 1000 F
can be
processed as described herein. Indeed, a heavy oil feedstock which is a vacuum
16 residuum, with greater than 95 volume percent boiling above I000 F, can
be
17 processed as described herein to produce the synthetic crude. The sulfur
content of the
18 feedstock will be generally above 2 percent; a feedstock containing
greater than 4
19 percent sulfur and even greater than 6 percent sulfur can be processed
as described
herein. Likewise, the nitrogen content of the feedstock to the process will be
above
21 0.3 percent; a feedstock containing greater than 0.5 percent nitrogen
and even greater
22 than 1 percent nitrogen can also be processed as described herein.
Likewise, the
23 feedstock can contain more than 25 wppm of metal contaminants such as
nickel
24 and/or vanadium; a feedstock containing greater than 50 wppm metal
contaminants
and even greater than 100 wppm metal contaminants can be processed as
described
26 herein. It is a feature of the upgrading process that extra heavy crudes
containing very
27 large amounts of sulfur, nitrogen and metals can be processed in a
single step to
28 produce light and clean syncrudes that require a minimum of further
upgrading in the
29 production of desired fuel, lubricants and chemical feedstocks. Boiling
point
properties are used herein are normal boiling point temperatures, based on
ASTM
31 D1160.
- 6 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 Communication Link
2 The process of the invention includes use of a communication link
between
3 the target refinery and the upgrading facility. The communication link is
any means
4 whereby information can be passed between the target refinery and the
upgrading
facility. Examples of communication means which are suitable for the present
process
6 include the analog or digital communication means, including, for
example,
7 telephone, fax, wireless device, cellular, intranet, internet, microwave,
satellite, radio,
8 computer, or any other typical mode of communication to communicate date
or other
9 types of information. Communications between the target refinery and the
upgrading
facility may involve more than one type of communication link. Likewise,
11 communications between multiple refineries with a single upgrading
facility may
12 involve more than one type of communication link, with individual
refineries possibly
13 using different communication means from each other.
14 Upgrading Process
In one embodiment, the upgrading process comprises either a carbon rejection
16 process such as fluid coking, hydrocoking, or Flexicoking; or a hydrogen
addition
17 process such as hydrocracking, hydrotreating, hydrodewaxing,
hydrofinishing,
18 hydrodesulphurization, hydrodenitrification, hydrodemetallization, etc.
The upgrading
19 process may firther include other process steps to further enhance the
properties of
the custom tailored synthetic crude. These units can include but are not
limited to an
21 atmospheric distillation units, vacuum distillation units, reformer
units, separators,
22 and fractionators.
23 In another embodiment, the upgrading process comprises contacting the
heavy
24 oil feedstock with hydrogen in the presence of a catalyst for removing
contaminants
from the heavy oil feedstock and for reducing the boiling point range of the
heavy oil
26 feedstock. The effectiveness of the upgrading process may be indicated
by the degree
27 of conversion. For purposes of this disclosure, conversion is reported
as the ratio of
28 the amount by volume of 1000 F+ material in the upgrading product,
divided by the
29 amount by volume of 1000 F+ material in the upgrading process feed,
wherein the
ratio is subtracted from I. Conversion is reported here in terms of volume
percent.
- 7 -
CA 02680878 2014-01-15
1 CASH Catalyst
2 The highly active unsupported molybdenum sulfide based catalyst is an
3 unsupported slurry catalyst composition that can achieve 100 percent
conversion of
4 the heavy oil feedstock feed. A catalyst composition which is useful for
the present
process is disclosed, for example, in U.S. Patent Application 10/938202 filed
6 September 10, 2004 and U.S. Patent Application 10/938003 filed September
10, 2004.
7 U.S. Patent Application 10/938202 teaches a catalyst composition prepared
by a
8 series of steps, involving mixing a Group VIB metal oxide and aqueous
ammonia to
9 form an aqueous mixture, and sulfiding the mixture to form a slurry. The
slurry is
then promoted with a Group VIII metal. Subsequent steps involve mixing the
slurry
11 with a hydrocarbon oil and combining the resulting mixture with hydrogen
gas and a
12 second hydrocarbon oil having a lower viscosity than the first oil. An
active catalyst
13 composition is thereby formed. A catalyst composition which also may be
useful for
14 the present invention is disclosed in U.S. Patent Application 10/938003.
This
application discloses a slurry catalyst composition prepared in a series of
steps,
16 involving mixing a Group VIB metal oxide and aqueous ammonia to form an
aqueous
17 mixture and sulfiding the mixture to form a slurry. The slurry is then
promoted with a
18 Group VIII metal. Subsequent steps involve mixing the slurry with a
hydrocarbon oil,
19 and combining the resulting mixture with hydrogen gas (under conditions
which
maintain the water in a liquid phase) to produce the active slurry catalyst.
21 In one embodiment, the upgrading process comprises contacting the heavy
oil
22 feedstock with hydrogen in the presence of an unsupported slurry
catalyst. The
23 unsupported slurry catalyst is prepared by a process comprising: (a)
mixing a Group
24 VIB metal oxide and aqueous ammonia to form a Group VI metal compound
aqueous
mixture; (b) sulfiding, in an initial reactor, the aqueous mixture of step (a)
with a gas
26 comprising hydrogen sulfide to a dosage greater than 8 SCF (0.23 cubic
meters) of
27 hydrogen sulfide per pound of Group VIB metal to form a slurry; (c)
promoting the
28 slurry with a Group VIII metal compound; (d) mixing the slurry of step
(c) with
29 hydrocarbon oil having a viscosity of at least 2 cSt at 212 F (100 C) to
form a mixed
slurry; (e) combining the mixed slurry with hydrogen gas in a second reaction
zone,
- 8 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 under conditions which maintain the water in the mixed slurry in a liquid
phase,
2 thereby forming an active catalyst composition admixed with a liquid
hydrocarbon;
3 and (f) recovering the active catalyst composition. As used herein, the
abbreviation
4 SCF is used to represent "standard cubic feet", referenced to a
temperature of 60 F
(16 C) and 1 atmosphere total pressure.
6 The preparation of the unsupported slurry catalyst is illustrated in
Figure 1.
7 The active slurry catalyst composition is prepared by mixing line 5,
containing an
8 oxide of Group VIB metal such as tungsten or molybdenum, and line 7,
containing
9 aqueous ammonia, in a mixing zone 10. The temperature of the mixing zone
is
generally in the range from about 80 F to about 200 F, preferably from about
100 F
11 to about 150 F, and most preferably from about 110 F to about 120 F. The
pressure
12 of the mixing zone 10 is generally from about atmospheric pressure to
about 100 psig,
13 preferably from about 5 psig to about 35 psig, and most preferably from
about 10 psig
14 to about 35 psig. The Group VIB metal oxide is dissolved in water
containing the
ammonia. The amount of ammonia added is based on the ratio of NH3 to Group VIB
16 oxide in lbs/lbs and generally ranges from 0.1 lbs/lbs to about 1,0
lbs/lbs, preferably
17 from about 0.15 lbs/lbs to about 0.50 lbs/lbs, and most preferably from
about 0.2
18 lbs/lbs to about 0.30 lbs/lbs. The dissolved metal oxide in aqueous
ammonia is moved
19 via line 15 to the first reaction zone.
The amount of hydrogen sulfide (line 9) added to the reaction zone 20 is based
21 on the ratio of I-12S to Group VIB metal oxide in SCF/lbs and generally
ranges from
22 4.0 SCF/lbs to about 20 SCF/lbs, preferably from about 8.0 SCF/lbs to
about 18
23 SCF/lbs, and most preferably from about 12 to 14 SCF/lbs. The reaction
time in the
24 first reaction zone ranges from about 1 hour to 10 hours, preferably
from 3 hours to 8
hours, and most preferably from about 4 hours to 6 hour per pound of Group VIB
26 metal oxide. Conditions include a temperature in the range from 80 F to
200 F,
27 preferably in the range from I00 F to 180 F, and most preferably in the
range from
28 130 F to 160 F. Pressure is in the range from 100 to 3000 psig,
preferably in the
29 range from 200 to 1000 psig, and most preferably from 300 to 500 psig.
The resultant
slurry is the catalyst precursor in an aqueous slurry phase.
- 9 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
The resultant slurry is combined with a Group VIII metal compound such as
2 Ni or Co, as disclosed in U.S. Patent No. 5,484 755. As an enhancement of
the
3 denitrogenation activity of the active slurry catalyst of the present
invention, it is
4 preferred that a Group VIII metal compound be added to the slurry before
mixing the
slurry with feed oil and a hydrogen containing gas at elevated temperature and
6 pressure. Such Group VIII metals are exemplified by nickel and cobalt. it
is preferred
7 that the weight ratio of nickel or cobalt to molybdenum range from about
1:100 to
8 about 1:2. It is most preferred that the weight ratio of nickel to
molybdenum range
9 from about 1:25 to 1:10, i.e., promoter/molybdenum of 4-10 weight
percent. The
Group VIII metal, exemplified by nickel, is normally added in the form of the
sulfate,
11 and preferably added to the slurry after sulfiding at a pH of about 10
or below and
12 preferably at a pH of about 8 or below. Group VIII metal nitrates,
carbonates or other
13 compounds may also be used. In view of the high activity of the slurry
catalyst of the
14 present invention, the further promotion by Group VIII metal compounds
is very
advantageous.
16 The slurry containing the Group VIII metal promoter is moved, via line
25, to
17 mixing zone 30. Mixing zone 30 employs an inert atmosphere which can
comprise
18 nitrogen, refinery gas, or any other gas having little or no oxygen. The
slurry and a
19 hydrocarbon oil (line 11), such as VG0, are mixed continuously in a high
shear mode,
forming a mixed slurry, to maintain a homogeneous slurry in mixer 30. High
shear
21 mixing encompasses a range from 100 to 1600 RPM. Preferably the mixing
rate is
22 greater than 500 RPM and most preferably greater than 1500 RPM.
23 The hydrocarbon oil has a kinetic viscosity of at least 2 cSt (32.8
SSU)
24 212 F. The kinetic viscosity can generally range from about 2 cSt (32.8
SSU)
212 F to about 15 cSt (77.9 SSU) 212 F, preferably from about 4 cSt (39.5 SSU)
26 212 F to about 10 cSt (59.2 SSU) @ 212 F, and most preferably from
about 5 cSt
27 (42.7 SSU) @ 212 F to about 8 cSt (52.4 SSU) @ 212 F. The hydrocarbon
oil causes
28 the initial transformation of the catalyst precursor to an oil base from
a water base.
29 The ratio of Group VIB metal oxide to oil is at least less than 1.0,
preferably less than
0.5, and more preferably less than 0.1. If the kinetic viscosity of the oil is
below about
' 31 2 cSt (32.8 SSU) @ 212 F or above about 15 eSt (77.9 SSU) @ 212 F,
the first
- 10 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 transformation of the catalyst precursor wifl result in catalyst
particles agglomerating
2 or otherwise not mixing.
3 The Mixed slurry from mixing zone 30 moves to reaction zone 40 via line
35,
4 Hydrogen is continuously added to the mixture reaction zone 40, and high
shear
mixing is employed in the reaction zone 40 in order to maintain a homogenous
slurry.
6 Hydrogen is added at low pressure prior to reactor 40 and at high
pressure following,
7 reactor 40. This is done in order to keep water in liquid phase in
reactor 40, change
8 \vat& to Vapor phase after reactor 40 in order to flash off the water.
When the low-42
9 rate is used in reactor 40, water is Still in liquid phase,. Following
reactor 40, more El2
is added, so the water changes to vapor phase, permitting separation from oil
slurry in
11 high pressure separator. The process conditions of reactor 40 are
critical to forming
12 the final catalyst. The water in the mixture must be maintained in a.
liquid phase.
13 The temperature of the reaction zone 40 generally ranges from ;about 300
E to
14 600 F, preferably from about 350 F to about 500 F, and most preferably
from &iota
350 F to: about 4507. The press-uro of the reaction zone 40 generally ranges
from
16 about 100 psig to about 3000 psig, preferably from about 200 psig to
about 1000 psig,
17 and most:preferably fsrorri about 300 psig to about 500 psig. The
hydrogen flow to the
18 reaction zone 40 generally ranges from about 300 SCFB to about 2000
SCFB,
19 preferably from about 300 SUB to about 1000 SCFB, and most preferably
from
about 300 SCFB to about 500 SCFB. The reJetion time in the reaction zone 40
ranges
21 from about 10 minutes to 5 hours, preferably from 30 minutes to 3 hours,
and most
22 preferably from about I hour to 1,5 hours. The resultant slurry mixture
is the active
23 catalyst composition in admixture with the hydrocarbon oil,
24 'Be shirty mixture IS passed, through hoe 55, to high pressnte separator
50.
More hydrogen is added in line 55 so the water Changes to vapor phase. It can
then be,
26 separated from oil slurry in the high pressure Separator 50. The high
pressure
27 separator operates,in.a range from 300 .Fte 7009ESO and Water are
remoVed
28 overhead through line 45 and passed to a three phase separator. The
unsupported
29 slurry catalyst is moved through line 65 to storage tank 60. The
unsupported slurry
catalyst is continuously mixed in storage. tank 60 to maintain a homogenous
slurry in
-11-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 a hydrogen atmosphere with little or no oxygen. In this way, the catalyst
activity and
2 stability are maintained.
3 The unsupported slurry catalyst may be used for upgrading heavy oil
4 feedstock. Following preparation of the unsupported slurry catalyst, the
upgrading
process comprises: (a) combining, in an upgrading reactor under
hydroprocessing
6 conditions, heavy feed, hydrogen gas, fresh catalyst slurry composition,
and recycle
7 slurry composition; (b) passing the effluent of the upgrading reactor to
a separation
8 zone wherein products boiling at temperatures up to 9.0097 are passed
overhead; (c)
9 passing the material remaining in the separation zone from step (b) to a
constantly
stirred catalyst storage tank; and (d) passing at least a portion of the
material in the
11 constantly stirred catalyst storage tank back to the upgrading reactor
of step (a).
12 Reference is now made to Fig. 2, which illustrates an embodiment of the
13 upgrading process. Other embodiments of the upgrading process are
disclosed in U.S.
14 Serial Numbers 11/305377, 11/305378, 11/305359, 11/303425, 11/303426,
11/303427. The process of the present invention can be operated in either a
single, or
16 in multiple, stage modes. A single stage upgrading reactor 10 is shown
in Fig. 2. An
17 optional second stage (not shown) may be, for example, an integrated
hydrotreater. In
18 the process shown in Fig. 2, the heavy oil feedstock 25 is contacted
with the
19 unsupported slurry catalyst and a hydrogen-containing gas (line 5) at
elevated
temperatures and pressures in one or more continuously stirred tank reactors
or
21 ebullated bed catalytic reactors The unsupported slurry catalyst is
composed of up to
22 95 wt percent recycle material (line 30) and 5 wt percent fresh catalyst
(line 15). The
23 feed, catalyst slurry and hydrogen-containing gas are mixed in upgrading
reactor 10 at
24 a residence time and temperature sufficient to achieve measurable
cracking rates.
26 The effluent from the upgrading reactor 10 passes through line 35 to the
hot
26 high pressure separator 40. The resultant light oil (45) is separated
from solid catalyst
27 and unconverted heavy oil (70) in the hot high pressure separator 40,
and passes
28 through line 45 to middle distillate storage. Alternately, the light oil
may be sent to
29 the second-stage reactor (not shown). This reactor is typically a fixed
bed reactor used
for hydrotreating of oil to further remove sulfur and nitrogen, and to improve
product
-12-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
qualities. The product (45) is free of catalyst and does not require settling,
filtration,
2 centrifugation, etc.
3 In the hot high pressure separator 40, substantially all of the upgraded
4 products generated from the upgrading zone 10 goes overhead as gas-vapor
stream
45. The liquid in the bottom of the hot high pressure separator 40, composed
primarily
6 of unconverted oil and active catalyst, is passed through line 70 to the
recycle catalyst
7 storage tank 60. This tank is constantly stirred, using mixer 55, and a
constant
8 reducing atmosphere is maintained by the addition of hydrogen (line 65).
Excess
9 hydrogen may be removed by bleed stream 50. The catalyst slurry is
recycled back to
upgrading reactor 10 as needed through line 30. Up to as much as 95 wt percent
of the
11 catalyst used in the upgrading reactor is recycled in this way.
12 In a preferred embodiment, the upgrading process is operated at up to
100
13 percent conversion, based on a target temperature of 1000 F. These
extremely high
14 conversion levels are possible by maintaining a reducing atmosphere
throughout the
upgrading, separation and storage steps, and.not allowing the catalyst
composition to
16 settle at any time. In one embodiment, the reducing atmosphere is
controlled by
17 maintaining the catalyst in a hydrogen-rich atmosphere at all times.
18 In another embodiment, separation in the hot high pressure separator is
the
19 only separation needed to separate the catalyst from the product oil.
The product oil is
purified and cracked sufficiently that it can be used directly for
distillation into fuel
21 and lubricant base oil cuts, with only minor further processing being
required before
22 sale or transportation to a target refinery. Throughout the process,
substantial
23 temperature and pressure fluctuations are tolerated with only minor
precipitate
24 formation of supercondensates and coke. Further, the catalyst can be
maintained and
recycled numerous times with minimal fouling and deactivation.
26 For the first-stage operation as depicted in upgrading reactor 10, the
reaction
27 temperatures for heavy oil feedstocks are normally above about 700 F,
preferably
28 above 750 F, and most preferably above 800 F in order to achieve high
conversion.
29 Maximum temperatures are in the range of 900 F. Hydrogen partial
pressures range
from 350 to 4500 psi and hydrogen to oil ratio is from 500 to 10,000 SCFB. The
-13-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 concentration of the active slurry eatalYSt in the heavy oil is normally
from about 100
2 to 20,000 ppm expressed as weight of metal (molybdenum) to weight of
heavy oil
3 feedstock, Typically, higher catalyst to oil ratio will give higher
conversion for sulfur,
4 nitrogen and metal removal, as well as the higher cracking conversion.
The high
pressure separator temperature can be as high as 800 F. Near 100 percent
6 demetalation conversion and 1000 F+ cracking conversion of the heavy oil
can be
7 achieved at appropriate process conditions, while the coke yield can be
maintained at
8 less than about 1 percent.
9 The process conditions for the second-stage (not shown in Figure 2) are
typical of heavy oil hydrotreating conditions. The second-stage reactor may be
either
11 a fixed, ebullated or a moving bed reactor. The catalyst used in the
second-stage
12 reactor is a hydrotreating catalyst such as those containing a Group VIB
and/or a
13 Group VIII metal deposited on a refractory metal oxide. By using this
integrated
14 hydrotreating process, the sulfur and nitrogen content in the product
oil can be very
low, and the product oil qualities are also improved.
16 In the present invention, product 45 from the upgrading process is a
syncrude
17 having the properties selected by a target refinery for which the
tailored syncrude is
18 prepared. It is a feature of the invention that the upgrading process,
as described
19 herein, is sufficiently flexible to be able to quickly adjust process
conditions, and thus
to make a first syncrude which is tailored for a first target refinery, and,
immediately
21 afterwards, a second syncrude which is tailored for a second target
refinery (or in
22 response to a request for a different syncrude from the first target
refinery. In this
23 way, a single upgrading process, located at a convenient location with
respect to the
24 hydrocarbon resource and all of the refineries which it serves, can
provide multiple
syncrudes, each tailored for the current needs of particular individual
refinery,
26 Refining DataSet
27 In the process of this invention, a target refinery specifies properties
of a
28 tailored syncrude for use in the refinery. The desired properties may be
as simple as
29 specifying, for example, the boiling range, the sulfur content or the
metals content of
the syncrude. In most cases, a number of properties may be specified, such as,
for
- 14 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 example, one or more. of physical properties (including density,
viscosity, color);
2 contaminant content (including sulfur, nitrogen, oxygen, metals, water);
distillation
3 properties (including the full distillation curve by ASTM D1160, mid-
boiling point,
4 end boiling point,, initial boiling point, flash point); hydrocarbon
components
(including. paraffins, cycloparaffins, aromatics, asphgtenes, microcarbon
residue) and
6 the like.
7 The methods which are used for specifying the properties of a
tailored
8 syncrude are not critical for the invention. Modern refineries are, well
equipped to
9 determine the desired properties of a feed to the refinery, using market
information,
customer requirements, cost structures of products, expert intelligence, as
well at
11 knowledge of the refinery, including modeling dataõ.process data,
planning data, and
12 analysis input data. Any or all of these may be employed to best define
the properties
13 of a desired tailored synctude.
14 Feedstock .Dataset
A feedstock dataset Characterizes the heavy oil feedstock which is upgraded in
16 the presenfprocess. This dataset will generally include specific values
for various
17 physical, chemical and compositional properties of the 'feedstock, which
are supplied
18 to the upgrading dataset for determining upgrading process conditions
needed to
19 produce the desired syncrude. Example properties which may be specified
include one
or more of physical properties (including density, viscosity, color);
contaminant
21 content (including sulfur; nittogen, oxygen, metals, water);
distillation properties
22 (including the full distillation curve by ASTM D1160, mid-boiling point,
end boiling
23 point, initial boiling point, flash point); hydrocarbon components
(including paraffins,
24 cycloparaffins, aromatics, asphaltenes, tnicrocarbortresidue); and the
like:
Upgrading Dataset
26 An upgrading dataset characterizes the:performance of the upgrading
process.
27 Typically, the dataset is developed.from the feedstock datasetand the
refining dataset,
28 using an understanding of the upgrading process itself. Such
understanding may
29 derive from one ormore of the following: technical expert analysis,
mathematical
3.0 and/or computer models, historical data, experimental data, current
operating data,
- 15 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
analytical data and the like. For the purposes of the present invention, these
methods
2 are used for comparing the quality of the heavy oil feedstock, via the
feedstock
3 dataset, with the requirements of the target refinery, using the refining
dataset, to
4 develop a set of upgrading operating conditions for producing a tailored
syncrude
which meets the requirements of the target refinery. The set of operating
conditions
6 and instructions which develop from this comparison is termed the
upgrading dataset.
7 It is expected that the dataset may include specifications to at least
one of reaction
8 temperature, heavy oil feedstock rate, hydrogen rate, catalyst
circulation rate, reaction
9 pressure, reactor size, number of reactor modules, product separation
parameters such
as cutpoint, number of individual fractions recovered, characterization of at
least one
11 of the fractions recovered, additional product upgrading steps, such
additional
12 hydrotreating, hydrocracking and/or isomerization and the like.
13 Tailored Synthetic Crude
14 The tailored synthetic crude (or "syncrude") is provided to the target
refinery
for further refining. The properties of the syncrude have been tailored to
match the
16 communicated requirements of the target refinery. In one embodiment, the
upgrading
17 process is effective to converting high amounts of extra heavy crude
oils to useful
18 products in a single step of hydroprocessing. It is normally the high
amounts of sulfur,
19 metals, asphaltenes and otherwise refractory residua molecules which
refineries prefer
to be much reduced in the tailored syncrude. Thus, a typical tailored syncrude
of the
21 present process will generally have a 95 percent boiling point (by ASTM
D1160) of
22 less than 1200 F, preferably of less than 1100 F, and more preferably of
less than
23 1000 F. As used herein, boiling points which are reported for liquid
materials are
24 referenced to a pressure of 1 atmosphere, unless stated otherwise.
Likewise, the
tailored syncrude will typically contain less than 4 percent by weight sulfur,
more
26 preferably less than 2 percent by weight sulfur and still more
preferably in the range
27 of 0.2 to 2.0 percent by weight sulfur. Likewise, the tailored syncrude
will typically
28 contain less than 100 ppm total metal contaminants, preferably less than
75 ppm total
29 metal contaminants, and more preferably less than 30 ppm total metal
contaminants.
Likewise, the 'API Gravity of the tailored syncnide will typically be greater
than 5,
31 preferably greater than 10 and more preferably in the range of 20 to 45.
It will be
- 16-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
recognized by the skilled practitioner that a. single tailored synerude may
meet only
2 one (or less than the total) of these compositional and property limits.
This is.
3 expected, since each target refinery will have varying needs which may
'further vary
4 from time to time through the year.
Target. Refinery
6 The target refinery is the. recipient of the tailored syncrude. As will
be clear to
7 the skilled practitioner, any remote processing system for the tailored
syncrude would
8 constitute a target refinery. Thus, the refinery, as contemplated here,
may range in
9 scale and complexity from the 250,000 bbl/day range with a complex
processing
scheme and literally hundreds of individual products, to a marketer who
fractionates
11 the tailored syncrude and distributes the individual fractions to
customers for use as
12 fuels and lubricants, or as feedstocks to further processing.
13 The synthetic crude which is prepared .as described herein may be
tailored
14 such that minimal additional processing is required. An inherent
advantage thereof is
that much of the tailored synthetic crude can be converted to -useful fuel and
lubricant
16 products, with a minimal production of less valuable by-prodacts.
Example fuels
17 which may be prepared in the target refinery include naphtha, gasoline,
jet fuel,
18 kerosene,. diesel fuel, wherein the boiling ranges of these products are
defined by or
19 derived from the standard specifications. Likewise, example lubricant
base oils may
be produced by from the tailored synthetic crude. In one embodiment, the
process of
21 the invention provides a tailored synthetic crude, such that wherein at.
least 75 percent
22 by volume, preferably at.least 90 percent by volume, and more preferably
at least 95
23 percent by volume of the tailored synthetic crude which is transported
to the target
24 refinery is converted to liquid fuel products in the target refinery.
Transportation
26 The tailored synthetic etude will be transported by a transportation
means,
27 including by, for example, railroad., truck, ship, pipeline, or airplane
in containers that
28 include tanks, vessels, and containerized units. In one embodiment, the
tailored
29 synthetic crude will .be modified, if needed, to permit transportation
using
conventional means for moving petroleum stocks. Thus, a tailored synthetic
crude
- 17 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
may be fractionated prior to being transported, in order to reduce a potential
vapor
2 pressure hazard. Such processes are well known, and do not require
additional details.
3 Fig. 3 illustrates the production of two different custom tailored
synthetic
4 crudes for two target refineries having different "synthetic trim crude"
needs
produced from one heavy oil feedstock upgrading facility. A first target
refinery (10)
6 communicates its requirements (I) of a desired "synthetic trim crude" to
the heavy, oil
7 feedstock upgrading facility (20). The heavy oil feedstock upgrading
facility (20) uses
8 these requirements and the data that represents the heavy oil feedstock
feed source
9 (16) to set upgrading process conditions needed to produce the tailored
synthetic
crude for target refinery (10). Information (2) is communicated from upgrading
11 facility (20) to target refinery (10) and upon agreement of pricing,
quantity, and
12 delivery times, first tailored synthetic crude (5) is produced and
delivered to target
13 refinery (10).
14 Likewise, a second target refinery (30) communicates its requirements
(3) of a
desired second "synthetic trim crude" to the heavy oil feedstock upgrading
facility
16 (20). The heavy oil feedstock upgrading facility (20) uses these
requirements and the
17 data that represents the heavy oil feedstock feed source (16) to set
upgrading process
18 conditions needed to produce the tailored synthetic crude for target
refinery (30).
19 Information (4) is communicated from upgrading facility (20) to target
refinery (30)
and upon agreement of pricing, quantity, and delivery times, second tailored
synthetic
21 crude (6) is produced and delivered to target refinery (30). It should
be noted that the
22 upgrading facility (20) will either process both first and second
tailored synthetic
23 crudes in a batch sequence mode where one tailored synthetic crude (5)
is produced
24 and the order is completed followed by the other tailored synthetic
crude (6).
Alternatively, the upgrading facility (20) could have enough capacity or more
than
26 one upgrading unit to run both first tailored synthetic crude (5) and
second tailored
27 synthetic crude (6) in tandem in a continuous process mode. The overall
scheme is
28 essentially identical if more than 2 tailored crudes are desired and
prepared.
29 Other benefits of this process include custom tailored synthetic crudes
that
exhibit properties and fraction cuts that are a typical (and rarely if ever
appear) in
31 native oils. This type of tailored synthetic crude is created by
altering operating
- 18 -
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
1 parameters and the various upgrader conversion units. By selectively
biasing the
2 creation clone or more fractions, tailored synthetic crude can be
produced that
3 matches the available capacity of a refinery and thus relieve the
refinery of having to
4 purchase intermediate streams. For example, tailored synthetic crude
could be
produced that is rich in gas oils, which would allow a target refinery that
typically
6 imports VGO to eliminate that purchase. This option would not be
available when
7 filling out crude slates based on traditional crude oil because lighter
and heavier
8 components are naturally present in those crudes.
9 Additional benefits from this process include reduction in waste such as
coke
and sulfur. The final tailored synthetic crude will be more hydrogenated, thus
11 lowering the hydrogen requirements at the target refinery. The target
refinery will
12 have less waste produced due to the lower sulfur, nitrogen, and metal
concentration in
13 the custom tailored synthetic crude. The target refinery will not have
to produce low
14 value product streams such as gas oils and asphaltic road mix. The
target refinery will
have increased catalyst life in their reactor systems due to a much cleaner
tailored
16 synthetic crude source.
17 EXAMPLE
18 Example:
19 Refinery planners at company downstream locations run weekly linear
program models to optimize the refinery's crude slate, operation, and
utilization,
21 nominally 20 weeks in advance of the actual processing date. The base
crude slate is
22 chosen, and the linear program model is run again substituting the
tailored synthetic
23 crude for all or some of the base crude slate. The willing-to-pay-price
and optimum
24 volume are calculated. For example Refinery "A" may specify a 30 days
supply of
100 MBPD 28.6 API syncrude with 10 percent bottoms, 80 percent middle
distillates
26 and gas oil, and 10 percent naphtha at $32.12 per bbl. This information
would be
27 communicated to the planner at Upgrader "1". Simultaneously, Refinery
"B" may
28 specify a need for similar 30 days supply of 601v1BPD 36 AN bottomless
Synthetic
29 Precision Crude Oil at $37.16 per bbl, and again the information is
communicated to
Upgrader "1" planner. Upgrader "1" is capable of producing a nominal 200 MBPD,
-19-
CA 02680878 2009-09-14
WO 2008/115230
PCT/US2007/064222
and would run for 15 days to produce the 3MM bbls of tailored synthetic crude
for
2 Refinery "A" and then switch to production for Refinery "13" and would
run for 9
3 days to produce the 1.8 MM bills required.
- 20 -
