U.S. patent application number 10/432826 was filed with the patent office on 2004-04-15 for method of refining petroleum.
Invention is credited to Fujimura, Yasushi, Imura, Kozo, Inomata, Makoto, Okada, Tsuyoshi, Sasaki, Hajime.
Application Number | 20040069685 10/432826 |
Document ID | / |
Family ID | 18836694 |
Filed Date | 2004-04-15 |
United States Patent
Application |
20040069685 |
Kind Code |
A1 |
Inomata, Makoto ; et
al. |
April 15, 2004 |
Method of refining petroleum
Abstract
The oil refining method according to the present invention
comprises the fractional distillation process 1 for distilling and
separating the feed oil into the distillate M1 and the residue M2;
the hydrorefining process 2 wherein at least a part of the
distillate M1 is refined by hydrogenation and desulfurized thereby
to obtain the hydrorefined oil M3; the solvent deasphalting process
3 wherein the residue M2 is deasphalted with a solvent thereby to
obtain the deasphalted oil M4 as an extract and asphaltene (pitch)
M5 as the residue; the hydrodemetalizating/desulfurizi- ng process
4 wherein at least a part of the deasphalted oil M4 is demetalized
and desulfurized by hydrogenation thereby to obtain the HDMS
refined oil M6; and the first mixing process 5 wherein a part of
the HDMS refined oil M6 and at least a part of the hydrorefined oil
M3 are mixed thereby to produce oil products.
Inventors: |
Inomata, Makoto;
(Ibaraki-ken, JP) ; Fujimura, Yasushi;
(Ibaraki-ken, JP) ; Okada, Tsuyoshi;
(Kanagawa-ken, JP) ; Imura, Kozo; (Kanagawa-ken,
JP) ; Sasaki, Hajime; (Kanagawa-ken, JP) |
Correspondence
Address: |
Darby & Darby
805 Third Avenue
New York
NY
10022
US
|
Family ID: |
18836694 |
Appl. No.: |
10/432826 |
Filed: |
May 22, 2003 |
PCT Filed: |
November 30, 2001 |
PCT NO: |
PCT/JP01/10489 |
Current U.S.
Class: |
208/211 ;
208/177; 208/212 |
Current CPC
Class: |
C10G 65/16 20130101;
C10G 2300/107 20130101; C10G 67/16 20130101 |
Class at
Publication: |
208/211 ;
208/212; 208/177 |
International
Class: |
C10G 045/00; C10G
067/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2000 |
JP |
2000366013 |
Claims
1. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into a distillate and a residue; a
hydrorefining process wherein at least a part of the distillate
obtained in the fractional distillation process is refined and
desulfurized by hydrogenation in the presence of hydrogen and
catalyst thereby to obtain a hydrorefined oil; a solvent
deasphalting process wherein the residue is deasphalted with a
solvent thereby to obtain a deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein at least a part
of the deasphalted oil is demetalized and desulfurized by
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain an HDMS refined oil that has been demetalized and
desulfurized; and a first mixing process wherein a part of the HDMS
refined oil and at least a part of the hydrorefined oil are mixed
thereby to obtain one of the oil products.
2. An oil refining method according to claim 1, wherein the oil
product obtained in the first mixing process is gas turbine fuel,
while extraction ratio of vanadium content included in the
deasphalted oil to the vanadium content included in the residue as
the feed oil is controlled to become 20% or lower in the solvent
deasphalting process, and demetalizing and desulfurizing conditions
for producing the HDMS refined oil from the deasphalted oil in the
hydrodemetalizating/desulfuri- zing process are selected so as to
achieve the a vanadium content of 2 wt ppm or lower and a sulfur
content of 0.5 wt % or lower included in the HDMS refined oil.
3. An oil refining method according to claim 1, wherein the oil
product obtained in the first mixing process is gas turbine fuel,
and the mixing condition in the first mixing process is selected so
as to achieve the vanadium content of 0.5 wt ppm or lower included
in the gas turbine fuel.
4. An oil refining method according to claim 1, wherein the
remainder of the HDMS refined oil is provided as an intermediate
oil product to be used as a feed stock for fluid catalyst cracking
or hydrocracking process.
5. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into a distillate and a residue; a
hydrorefining process wherein at least a part of the distillate
obtained in the fractional distillation process is refined and
desulfurized by hydrogenation in the presence of hydrogen and a
catalyst thereby to obtain a hydrorefined oil; a solvent
deasphalting process wherein the residue is deasphalted with a
solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein at least a part
of the deasphalted oil is demetalized and desulfurized by
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain an HDMS refined oil that has been demetalized and
desulfurized; a vacuum fractional distillation process wherein the
HDMS refined oil is distilled in a vacuum and separated into vacuum
gas oil and vacuum residue; and a second mixing process wherein at
least a part of the vacuum gas oil and at least a part of the
hydrorefined oil are mixed thereby to obtain one of the oil
products.
6. An oil refining method according to claim 5, wherein the oil
product obtained in the second mixing process is gas turbine fuel,
while the extraction ratio of the vanadium content included in the
deasphalted oil to the vanadium content included in the residue as
the feed oil is controlled to become 30% or lower in the solvent
deasphalting process, and demetalizing and desulfurizing conditions
for producing the HDMS refined oil from the deasphalted oil in the
hydrodemetalizating/desulfuri- zing process are selected so as to
achieve the vanadium content of 20 wt ppm or lower, and a sulfur
content of 0.5 wt % or lower included in the HDMS refined oil,
while the vanadium content in the vacuum gas oil obtained in the
vacuum fractional distillation process is 1 wt ppm or lower.
7. An oil refining method according to claim 5, wherein the oil
product obtained in the second mixing process is gas turbine fuel,
and the mixing condition in the second mixing process is selected
so as to achieve the vanadium content of 0.5 wt ppm or lower
included in the gas turbine fuel.
8. An oil refining method according to claim 5, wherein the vacuum
gas oil obtained by vacuum distillation of at least a part of the
HDMS refined oil is provided as an intermediate oil product to be
used as a feed stock for fluid catalyst cracking or hydrocracking
process.
9. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into a distillate and a residue; a
hydrorefining process wherein at least a part of the distillate
obtained in the fractional distillation process is refined and
desulfurized by hydrogenation in the presence of hydrogen and
catalyst thereby to obtain a hydrorefined oil; a vacuum fractional
distillation process wherein the residue is distilled in a vacuum
and separated into a vacuum gas oil and a vacuum residue; a solvent
deasphalting process wherein the vacuum residue is deasphalted with
a solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein the vacuum gas
oil and the deasphalted oil are mixed and the mixture is
demetalized and desulfurized by hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain an HDMS refined oil that
has been demetalized and desulfurized; and a third mixing process
wherein a part of the HDMS refined oil and at least a part of the
hydrorefined oil are mixed thereby to obtain one of the oil
products.
10. An oil refining method according to claim 9, wherein the oil
product obtained in the third mixing process is gas turbine fuel,
while the extraction ratio of vanadium content included in the
deasphalted oil to the vanadium content included in the residue as
the feed oil is controlled so as to be 15% or lower in the solvent
deasphalting process, and demetalizing and desulfurizing conditions
for producing the HDMS refined oil are selected so as to achieve
the vanadium content of 2 wt ppm or lower and a sulfur content of
0.5 wt % or lower included in the HDMS refined oil.
11. An oil refining method according to claim 9, wherein the oil
product obtained in the third mixing process is gas turbine fuel,
and the mixing condition in the third mixing process is selected so
as to achieve the vanadium content of 0.5 wt ppm or lower included
in the gas turbine fuel.
12. An oil refining method according to claim 9, wherein the
remainder of the HDMS refined oil is provided as an intermediate
oil product to be used as a feed stock for fluid catalyst cracking
or hydrocracking process.
13. An oil refining method according to any one of claims 1, 5 and
9, wherein the feed oil is a heavy oil having an API gravity of 20
or lower.
14. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into a distillate and a residue; a
solvent deasphalting process wherein the residue obtained in the
fractional distillation process is deasphalted with a solvent
thereby to obtain deasphalted oil as an extract and asphaltene
(pitch) as the residue; a hydrodemetalizating/desulfurizing process
wherein at least a part of the deasphalted oil is demetalized and
desulfurized by hydrogenation in the presence of hydrogen and a
catalyst thereby to obtain an HDMS refined oil that has been
demetalized and desulfurized; and a fourth mixing process wherein a
part of the HDMS refined oil and at least a part of the distillate
are mixed thereby to obtain one of the oil products.
15. An oil refining method according to claim 14, wherein the oil
product obtained in the fourth mixing process is gas turbine fuel,
while the extraction ratio of the deasphalted oil in the solvent
deasphalting process is controlled so that vanadium content thereof
becomes 25 wt ppm or lower, and demetalizing and desulfurizing
conditions for producing the HDMS refined oil are selected so as to
achieve the vanadium content of 2 wt ppm or lower and a sulfur
content of 0.5 wt % or lower included in the HDMS refined oil.
16. An oil refining method according to claim 14, wherein the oil
product obtained in the fourth mixing process is gas turbine fuel,
and the mixing condition in the fourth mixing process is selected
so as to achieve the vanadium content of 0.5 wt ppm or lower
included in the gas turbine fuel.
17. An oil refining method according to claim 14, wherein the
remainder of the HDMS refined oil is provided as an intermediate
oil product to be used as a feed stock for fluid catalyst cracking
or a hydrocracking process.
18. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into a distillate and a residue; a
solvent deasphalting process wherein the residue obtained in the
fractional distillation process is deasphalted with a solvent
thereby to obtain deasphalted oil as an extract and asphaltene
(pitch) as the residue; a hydrodemetalizating/desulfurizing process
wherein at least a part of the deasphalted oil is demetalized and
desulfurized by hydrogenation in the presence of hydrogen and a
catalyst thereby to obtain an HDMS refined oil that has been
demetalized and desulfurized; a vacuum fractional distillation
process wherein the HDMS refined oil is distilled in a vacuum and
separated into a vacuum gas oil and a vacuum residue; and a fifth
mixing process wherein at least a part of the vacuum gas oil and at
least a part of the distillate are mixed thereby to obtain one of
the oil products.
19. An oil refining method according to claim 18, wherein the oil
product obtained in the fifth mixing process is gas turbine fuel,
while the extraction ratio of the deasphalted oil in the solvent
deasphalting process is controlled so that vanadium content
included in the deasphalted oil becomes 50 wt ppm or lower, and
demetalizing and desulfurizing conditions for producing the HDMS
refined oil are selected so as to achieve the vanadium content of
20 wt ppm or lower and a sulfur content of 0.5 wt % or lower
included in the HDMS refined oil, while vanadium content included
in the vacuum gas oil obtained in the vacuum fractional
distillation process is set to 1 wt ppm or lower.
20. An oil refining method according to claim 18, wherein the oil
product obtained in the fifth mixing process is gas turbine fuel,
and the mixing condition in the fifth mixing process is selected so
as to achieve the vanadium content of 0.5 wt ppm or lower included
in the gas turbine fuel.
21. An oil refining method according to claim 18, wherein the
vacuum gas oil obtained by vacuum distillation of at least a part
of the HDMS refined oil is provided as an intermediate oil product
to be used as a feed stock for fluid catalyst cracking or a
hydrocracking process.
22. An oil refining method for producing oil products including a
plurality of intermediate oil products by refining a feed oil,
comprising: a fractional distillation process wherein the feed oil
is distilled and separated into distillate and a residue; a vacuum
fractional distillation process wherein the residue obtained in the
fractional distillation process is distilled in a vacuum and
separated into a vacuum gas oil and a vacuum residue; a solvent
deasphalting process wherein the vacuum residue is deasphalted with
a solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein the vacuum gas
oil and the deasphalted oil are mixed and the mixture is
demetalized and desulfurized by hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain an HDMS refined oil that
has been demetalized and desulfurized; and a sixth mixing process
wherein a part of the HDMS refined oil and at least a part of the
distillate are mixed thereby to obtain one of the oil products.
23. An oil refining method according to claim 22, wherein the oil
product obtained in the sixth mixing process is gas turbine fuel,
while the extraction ratio of the deasphalted oil in the solvent
deasphalting process is controlled so that vanadium content
included in the deasphalted oil becomes 70 wt ppm or lower, and
demetalizing and desulfurizing conditions for producing the HDMS
refined oil are selected so as to achieve the vanadium content of 2
wt ppm or lower and a sulfur content of 0.5 wt % or lower included
in the HDMS refined oil.
24. An oil refining method according to claim 22, wherein the oil
product obtained in the sixth mixing process is gas turbine fuel,
and the mixing condition in the sixth mixing process is selected so
as to achieve the vanadium content of 0.5 wt ppm or lower included
in the gas turbine fuel.
25. An oil refining method according to claim 22, wherein the
remainder of the HDMS refined oil is provided as an intermediate
oil product to be used as a feed stock for fluid catalyst cracking
or hydrocracking process.
26. An oil refining method according to any one of claims 14, 18
and 22, wherein the feed oil is a low-sulfur crude that includes a
sulfur content of 2.0 wt % or lower.
Description
TECHNICAL FIELD
[0001] The present invention relates to an oil refining method for
producing a plurality of oil products of high added value with a
high efficiency, and more particularly, to an oil refining method
for producing a plurality of oil products of high added value that
have different specifications with a high efficiency from a heavy
feed oil or a low sulfur oil.
BACKGROUND ART
[0002] Technologies of this type known in the prior art include the
following technologies that are capable of efficiently producing
oil products and intermediate products used for producing the
same:
[0003] (1) A technology for producing thermally cracked gasoline
and gas oil by separating a feed oil into distillate and
atmospheric residue through atmospheric distillation, distilling
the atmospheric residue in a vacuum and processing the vacuum
residue (VR) in a coker; and
[0004] (2) A technology that applies solvent deasphalting (SDA) to
the atmospheric residue and uses deasphalted oil (DAO) thus
obtained as a feed for a fluid catalytic cracking (FCC) process, or
applies vacuum distillation (VDU) to the atmospheric residue and
uses vacuum gas oil (VGO) thus obtained as a feed for fluid
catalytic cracking (FCC) process.
[0005] However, the technology (1) described above faces the
problem that the market for coker bottom (coke) is pressured by
over supply that hinders the construction of cokers which produce
coke as a byproduct.
[0006] The technology (2) described above has such a problem as
described below. Fuels for transportation such as gasoline and gas
oil can be produced by separating deasphalted oil and vacuum gas
oil from ultra heavy crude that is found in vast amount of reserves
or atmospheric residue of which an over supply is expected in the
future, and processing the deasphalted oil or vacuum gas oil by
fluid catalytic cracking (FCC) or hydrocracking (HCR) process. But
this scheme would cause supply-demand imbalance in the market of
fuels for transportation and power generation, since a higher
increase in the demand for electricity over the demand increase for
gasoline and gas oil is expected world over.
[0007] Besides the technologies (1) and (2) described above, there
is such a technology of producing gas turbine fuel (GTF) from ultra
heavy crude that includes much vanadium (V) content or from
atmospheric residue through solvent deasphalting process. However,
this technology also has the problem that increasing the yield
(extraction rate) of producing the deasphalted oil in the solvent
deasphalting process leads to higher contamination of the
deasphalted oil product by metals and/or residual carbon. This
results in increased process load (higher pressure, low LHSV) when
refining the deasphalted oil by demetalization and desulfurization,
thus making this method economically disadvantageous. When the
yield of deasphalted oil production is lowered to circumvent the
problem described above, the yield of the gas turbine fuel produced
decreases, leading to the new problem of increased production of
asphaltene (pitch) that has lower added value.
[0008] An object of the present invention is to provide a method of
refining oil for producing oil products (for example, gas turbine
fuel) that includes a vanadium (V) content of 0.5 wt ppm or lower
and intermediate oil products having metal content (V+Ni) of 30 wt
ppm or lower that can be used as the feed for a fluid catalytic
cracking (FCC) or a hydrocracking (HCR) process efficiently at the
same time, whether a particularly heavy feed oil or a feed oil
having a low sulfur content is used as the starting material.
DISCLOSURE OF THE INVENTION
[0009] A method for refining oil according to the first aspect of
the present invention is a method for producing oil products
including a plurality of intermediate oil products by refining a
feed oil, comprising a fractional distillation process for
separating the feed oil into distillate and a residue through
distillation; a hydrorefining process wherein at least a part of
the distillate obtained in the fractional distillation process is
refined and desulfurized by hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain a hydrorefined oil; a
solvent deasphalting process wherein the residue is deasphalted
with a solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein at least a part
of the deasphalted oil is demetalized and desulfurized by
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain HDMS refined oil that has been demetalized and desulfurized;
and a first mixing process wherein a part of the HDMS refined oil
and at least a part of the hydrorefined oil are mixed in order to
produce one of the oil products.
[0010] According to this refining method, since at least a part of
the hydrorefined oil is mixed with a part of the HDMS refined oil
in the first mixing process, it is possible to obtain an oil
product that has a sufficiently low vanadium (V) content such as
gas turbine fuel, and also to produce intermediate oil products
having a relatively low metal content (V+Ni) that can be used as
the feed for fluid catalytic cracking (FCC) or a hydrocracking
(HCR) process from the remainder of the HDMS refined oil.
[0011] Since the intermediate oil product used as the feed for a
fluid catalytic cracking or a hydrocracking process has more
lenient tolerance for metal contents than gas turbine fuel or the
like does, the yield of deasphalted oil produced in the solvent
deasphalting process can be improved by producing the gas turbine
fuel and the feed for a fluid catalytic cracking or a hydrocracking
process at the same time, thereby suppressing the production of
asphaltene (pitch) from the atmospheric residue.
[0012] A method for refining oil according to the second aspect of
the present invention comprises a fractional distillation process
for separating the feed oil into a distillate and a residue through
distillation; a hydrorefining process wherein at least a part of
the distillate obtained in the fractional distillation process is
refined and desulfurized through hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain a hydrorefined oil; a
solvent deasphalting process wherein the residue is deasphalted
with a solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein at least a part
of the deasphalted oil is demetalized and desulfurized through
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain HDMS refined oil that has been demetalized and desulfurized;
a vacuum fractional distillation process wherein the HDMS refined
oil is distilled in a vacuum and separated into vacuum gas oil and
vacuum residue; and a second mixing process wherein at least a part
of the vacuum gas oil and at least a part of the hydrorefined oil
are mixed thereby to produce one of the oil products.
[0013] According to this refining method described above, since at
least a part of the vacuum gas oil and at least a part of the
hydrorefined oil are mixed in the second mixing process, oil
products can be obtained that have a sufficiently low vanadium (V)
content such as gas turbine fuel. It is also possible to obtain an
intermediate oil product having a relatively low metal content
(V+Ni) that can be used as the feed for a fluid catalytic cracking
or a hydrocracking process from the remainder of vacuum gas oil or
the vacuum residue obtained by vacuum distillation, and even from
the HDMS refined oil.
[0014] Also because the HDMS refined oil is subjected to a vacuum
fractional distillation process to be separated into vacuum gas oil
and vacuum residue having low metal content and residual carbon
content by making use of the range of boiling points of the
distillation properties particularly in the vacuum fractional
distillation process, relatively high concentrations of vanadium
and metals can be allowed for the HDMS refined oil, thus improving
the yield of deasphalted oil in the solvent deasphalting process,
and therefore it is possible to suppress the production of
asphaltene (pitch) from the atmospheric residue.
[0015] A method for refining oil according to the third aspect of
the present invention comprises a fractional distillation process
for separating the feed oil into distillate and a residue through
distillation; a hydrorefining process wherein at least a part of
the distillate obtained in the fractional distillation process is
refined and desulfurized through hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain a hydrorefined oil; a
vacuum fractional distillation process wherein the residue is
distilled in a vacuum and separated into vacuum gas oil and vacuum
residue; a solvent deasphalting process wherein the vacuum residue
is deasphalted with a solvent thereby to obtain deasphalted oil as
an extract and asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein the vacuum gas
oil and deasphalted oil are mixed and the mixture is subjected to
hydrodemetalizating/desulfurizing process in the presence of
hydrogen and a catalyst thereby to obtain HDMS refined oil that is
demetalized and desulfurixed; and a third mixing process wherein a
part of the HDMS refined oil and at least a part of the
hydrorefined oil are mixed thereby to produce one of the oil
products.
[0016] According to this refining method, since a part of the HDMS
refined oil and at least a part of the hydrorefined oil are mixed
in the third mixing process, the vanadium (V) content of the mixed
oil thus obtained is decreased sufficiently and it is possible to
obtain an oil product used as gas turbine fuel. It is also possible
to obtain an intermediate oil product having a relatively low metal
content (V+Ni) that can be used as the feed for a fluid catalytic
cracking or a hydrocracking process even from the remainder of the
HDMS refined oil obtained by processing the mixture of the vacuum
gas oil and deasphalted oil in the
hydrodemetalizating/desulfurizing process.
[0017] Since the intermediate oil product used as the feed for a
fluid catalytic cracking or a hydrocracking process has a higher
tolerable concentrations of metal contents than those of gas
turbine fuel or the like, the yield of the deasphalted oil in the
solvent deasphalting process can be improved by producing the gas
turbine fuel and the feed for a fluid catalytic cracking or a
hydrocracking process at the same time, thereby suppressing the
production of asphaltene (pitch) from the atmospheric residue.
[0018] In case the present invention is applied to a heavy oil
having an API gravity of 20 or lower, the amount of pitch produced
can be made lower than in the prior art, in which a large quantity
of pitch that has a low commodity value generated as a byproduct,
and the yield of producing a plurality of oil products having a
high added values is improved, thus resulting in a greatly improved
productivity.
[0019] A method for refining oil according to the fourth aspect of
the present invention is a method for producing oil products
including a plurality of intermediate oil products by refining a
feed oil that includes low sulfur content, and comprises a
fractional distillation process for separating the feed oil into
distillate and a residue through distillation; a solvent
deasphalting process wherein the residue obtained in the fractional
distillation process is deasphalted with a solvent thereby to
obtain deasphalted oil as an extract and asphaltene (pitch) as the
residue; a hydrodemetalizating/desulfurizing process wherein at
least a part of the deasphalted oil is demetalized and desulfurized
through hydrogenation in the presence of hydrogen and a catalyst
thereby to obtain HDMS refined oil that has been demetalized and
desulfurized; and a fourth mixing process wherein a part of the
HDMS refined oil and at least a part of the distillate are mixed
thereby to produce one of the oil products.
[0020] According to this refining method, since a part of the HDMS
refined oil and at least a part of the hydrorefined oil are mixed
in the fourth mixing process, it is possible to obtain an oil
product such as gas turbine fuel that has a sufficiently low
vanadium (V) content. It is also possible to obtain an intermediate
oil product having low metal content (V+Ni) that can be used as the
feed for a fluid catalytic cracking or a hydrocracking process from
the remainder of the HDMS refined oil.
[0021] Since the intermediate oil product used as the feed for a
fluid catalytic cracking or a hydrocracking process has a higher
tolerable concentrations of metal contents than that of gas turbine
fuel or the like, the yield of deasphalted oil produced in the
solvent deasphalting process can be improved by producing the gas
turbine fuel and the feed for a fluid catalytic cracking or a
hydrocracking process at the same time, thereby suppressing the
production of asphaltene (pitch) from the atmospheric residue.
[0022] A oil refining method according to the fifth aspect of the
invention comprises a fractional distillation process for
separating the feed oil into distillate and a residue through
distillation; a solvent deasphalting process wherein the residue
obtained in the fractional distillation process is deasphalted with
a solvent thereby to obtain deasphalted oil as an extract and
asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein at least a part
of the deasphalted oil is demetalized and desulfurized by
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain HDMS refined oil that has been demetalized and desulfurized;
a vacuum fractional distillation process wherein the HDMS refined
oil is distilled in a vacuum and separated into vacuum gas oil and
vacuum residue; and a fifth mixing process wherein at least a part
of the vacuum gas oil and at least a part of the distillate are
mixed in order to produce one of the oil products.
[0023] According to this refining method, since at least a part of
the vacuum gas oil and at least a part of the distillate are mixed
in the fifth mixing process, it is possible to obtain an oil
product that has a sufficiently low vanadium (V) content such as
gas turbine fuel. It is also possible to produce an intermediate
petroleum product, that has relatively low metal content (V+Ni) and
can be used as the feed for a fluid catalytic cracking or a
hydrocracking process, from the remainder of the vacuum gas oil or
the vacuum residue obtained by vacuum distillation process, and
even from the HDMS refined oil.
[0024] Also, the HDMS refined oil is subjected to vacuum
distillation so as to separate into vacuum gas oil and vacuum
residue having low metal content and residual carbon content by
making use of the range of boiling points of the distillation
properties particularly in the vacuum fractional distillation
process, thus relatively high concentrations of vanadium and metals
can be allowed for the HDMS refined oil, thereby improving the
yield of deasphalted oil in the solvent deasphalting process, and
therefore it is possible to suppress the production of asphaltene
(pitch) from the atmospheric residue.
[0025] A oil refining method of the sixth aspect of the present
invention comprises a fractional distillation process for
separating the feed oil into distillate and a residue through
distillation; a vacuum fractional distillation process wherein the
residue obtained in the fractional distillation process is
distilled in a vacuum and separated into vacuum gas oil and vacuum
residue; a solvent deasphalting process wherein the vacuum residue
is deasphalted with a solvent thereby to obtain deasphalted oil as
an extract and asphaltene (pitch) as the residue; a
hydrodemetalizating/desulfurizing process wherein the vacuum gas
oil and the deasphalted oil are mixed and the mixture is
demetalized and desulfurized by hydrogenation in the presence of
hydrogen and a catalyst thereby to obtain HDMS refined oil that has
been demetalized and desulfurized; and a sixth mixing process
wherein a part of the HDMS refined oil and at least a part of the
distillate are mixed thereby to produce one of the oil
products.
[0026] According to this refining method, since a part of the HDMS
refined oil and at least a part of the distillate are mixed in the
sixth mixing process, the vanadium (V) content of the mixed oil
becomes sufficiently low and it is possible to obtain an oil
product that can be used as gas turbine fuel. It is also possible
to produce an intermediate oil product having sufficiently low
metal content (V+Ni) that can be used as the feed for a fluid
catalytic cracking or a hydrocracking process even from the
remainder of HDMS refined oil that is obtained by processing the
mixture of vacuum gas oil and deasphalted oil in the
hydrodemetalizating/desulfur- izing process.
[0027] Since the intermediate oil product used as the feed for a
fluid catalytic cracking or a hydrocracking process has a higher
tolerable concentration of metal contents than that of gas turbine
fuel or the like, the yield of deasphalted oil produced in the
solvent deasphalting process can be improved by producing the gas
turbine fuel and the feed for a fluid catalytic cracking or a
hydrocracking process at the same time, thereby suppressing the
production of asphaltene (pitch) from the vacuum residue.
[0028] When the method of one of fourth through sixth aspects of
the invention is applied to a crude oil having low sulfur content
of 2.0 wt % or lower, the amount of pitch produced can be made less
than in the prior art where a large quantity of pitch that has low
commodity value is produced, thus improving the yield of a
plurality of oil products having a high added values, resulting in
greatly improved productivity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 through FIG. 6 are process flow diagrams explaining
the first through sixth embodiments of the oil refining method
according to the present invention.
[0030] FIG. 7 through FIG. 12 are process flow diagrams explaining
the oil refining methods of the first through sixth experimental
examples.
BEST MODE FOR CARRYING OUT THE INVENTION
[0031] Now preferred embodiments of the oil refining method
according to the present invention will be described below with
reference to the accompanying drawings. It should be understood,
however, that the present invention is not limited to the
embodiments described below and, for example, any combination of
components of these embodiments is deemed to fall within the scope
of the present invention.
[0032] FIG. 1 is a process flow diagram explaining an embodiment of
the oil refining method according to the present invention, wherein
a heavy crude oil is used as feed oil from which gas turbine fuel
(GTF) and a feed for fluid catalytic cracking (FCC) process or a
feed for hydrocracking (HCR) process are produced at the same
time.
[0033] There is no limitation to the feed oil to be processed, and
any hydrocarbon oil ranging from crude oil to heavy oil can be
used. The description that follows will deal with cases where the
present invention is applied to heavy crude oil such as Orinoco
tar, particularly to heavy oils having an API gravity not higher
than 20 while achieving a remarkable effect of improving the yield
of producing a plurality of oil products having a high added
values.
[0034] API gravity is an index for classifying crude oils by the
physical properties thereof, and is calculated from the specific
gravity by the following formula, where S is the specific gravity
at 60 degrees Fahrenheit.
API=(141.5/S)-131.5
[0035] According to the method of this example where the heavy
crude oil described above is used as the feed oil, the feed oil is
first subjected to fractional distillation process 1 to separate
into a distillate M1 consisting of low-boiling point oil and a
residue M2 of high boiling point by distilling similarly to the
prior art. While a topper, which is a commonly used atmospheric
distillation apparatus, is preferably used as the fractional
distillation apparatus of this example, there is no limitation to
the apparatus as long as it is means for fractional distillation.
Distillates may be either collectively recovered without
classifying, or recovered individually after classifying by the
boiling point. In case distillates are recovered in a plurality of
classes and some class of the distillate satisfies the
specification requirements for petroleum, the hydrorefining process
2 that would follow may be omitted or bypassed as indicated by
arrow 11.
[0036] Then at least a part of the distillate M1 obtained in the
fractional distillation process 1 is introduced into the
hydrorefining process (HT process) 2 to be refined and desulfurized
by hydrogenation in the presence of hydrogen and a catalyst,
thereby producing hydrorefined oils M3, M3'.
[0037] In the hydrorefining process of the distillate M1, hydrogen
gas is mixed with the distillate M1 and the mixture is introduced
into a reactor filled with a CoMo catalyst or a NiMo catalyst where
sulfur and nitrogen contents included in the distillate M1 are
removed by hydrogenation in the presence of hydrogen under a high
pressure, followed by the separation of hydrogen gas in a
high-pressure separator thereby to obtain the hydrorefined oils M3,
M3'.
[0038] Apart from the hydrorefining process 2, the residue M2
obtained in the fractional distillation process 1 is introduced
into the solvent deasphalting process (SDA process) 3 to be
deasphalted with a solvent, thereby to obtain deasphalted oil (DAO)
M4 as an extract and asphaltene (pitch) M5.
[0039] In the solvent deasphalting process, the residue M2 is put
into contact with the solvent in counterflow in a solvent
extraction tower and is separated into deasphalted oil and
asphaltene (pitch) that includes metals and residual carbon in high
concentrations. The deasphalted oil is recovered together with the
solvent through the top of the tower, and the solvent is separated
from the recovered material in super-critical state. Asphaltene
(pitch) is recovered together with the solvent through the bottom
of the tower, and the solvent in the recovered material is removed
by evaporation.
[0040] It is known that, in solvent deasphalting process in
general, the extraction ratio of deasphalted oil from the feed oil
varies among components included in the deasphalted oil such as
sulfur, vanadium, nitrogen and residual carbon. According to the
present invention, in case the residue obtained by fractional
distillation of heavy oil is used as the feed oil, the extraction
ratio for the vanadium content included in the deasphalted oil to
the vanadium content included in the feed oil is preferably
controlled to within 20% when the atmosphere distilled residue is
used as the feed oil, or within 15% when the vacuum distilled
residue is used as the feed oil. There is not a specific lower
limit to the extraction ratio in either case, and the extraction
ratio may be in a range appropriately selected in accordance to the
type of feed oil and the vanadium content. In case the residue
obtained by fractional distillation of low-sulfur feed oil
including a sulfur content of 2.0 wt % or lower is used as the feed
oil, the vanadium content included in the deasphalted oil is
preferably controlled to within 25 wt ppm when atmosphere distilled
residue is used as the feed oil, or within 70 wt ppm when vacuum
distilled residue is used as the feed oil.
[0041] According to the present invention, refined oil can be
produced efficiently with the extraction ratio in the solvent
deasphalting process being maximized, without placing a significant
load on the hydrodemetalizating/desulfurizing process that follows
the solvent deasphalting process, in either of the cases described
above.
[0042] In case the refining process that follows the solvent
deasphalting process 3 includes only the
hydrodemetalizating/desulfurizing process 4, it is preferable to
control the extraction rate of the solvent deasphalting process 3
so that the extraction ratio for the vanadium content included in
the deasphalted oil M4 to the vanadium (V) content included in the
residue M2 used as the feed oil is 20% or lower.
[0043] At least a part of the deasphalted oil M4 obtained in the
solvent deasphalting process 3 is introduced into the
hydrodemetalizating/desulfu- rizing process (HDMS process) 4,
wherein the deasphalted oil is demetalized and desulfurized by
hydrogenation in the presence of hydrogen and a catalyst thereby to
obtain HDMS refined oil that has been demetalized and desulfurized.
The hydrodemetalizating/desulfurizing process is basically the same
as the hydrorefining process 2 described previously, and the
description thereof will be omitted.
[0044] The demetalizing and desulfurizing conditions for the HDMS
refined oil M6 obtained in the hydrodemetalizating/desulfurizing
process are preferably selected so as to achieve the vanadium (V)
content of 2 wt ppm or lower, preferably 1 wt ppm or lower, and a
sulfur content of 0.5 wt % or lower, preferably 0.3 wt % or
lower.
[0045] Then a part of the HDMS refined oil M6 obtained in the
hydrodemetalizating/desulfurizing process 4 and at least part of
the hydrorefined oil M3 obtained in the hydrorefining process 2 are
mixed in the first mixing process 5 thereby to obtain a petroleum
product.
[0046] In order to produce gas turbine fuel (GTF) as the oil
product obtained in the first mixing process 5, mixing condition is
set so as to achieve the vanadium (V) content of 0.5 wt ppm or
lower. In this case, when the vanadium content of the HDMS refined
oil M6 is assumed to be 1 wt ppm, for example, rate of the HDMS
refined oil M6 to the hydrorefined oil M3 is set to 1:1 or less
(that is, a smaller proportion of the HDMS refined oil M6) in
volume proportion for mixing, with the vanadium content in the
hydrorefined oil M3 being set to 0 wt ppm.
[0047] Of the HDMS refined oil M6 obtained in the
hydrodemetalizating/desu- lfurizing process 4, the remainder that
is not subjected to the first mixing process 5 is used as an
intermediate oil product to be used as the feed for the fluid
catalytic cracking (FCC) process or the hydrocracking (HCR)
process. Of the hydrorefined oil M3, the remainder that is not
subjected to the first mixing process 5 may be used as oil product
M3' such as naphtha, gasoline, kerosene, or gas oil.
[0048] According to the oil refining method described above, since
a part of the HDMS refined oil M6 and at least a part of the
hydrorefined oil M3 are mixed, it is possible to obtain an oil
product that has a sufficiently low vanadium (V) content, such as
gas turbine fuel. It is also possible to produce an intermediate
oil product having relatively low metal content (V+Ni) that can be
used as the feed for fluid catalytic cracking (FCC) or
hydrocracking (HCR) process, from the remainder of HDMS refined oil
M6 and therefore a plurality of oil products having a high added
values can be produced efficiently at the same time.
[0049] Since the intermediate oil product used as the feed for
fluid catalytic cracking (FCC) or hydrocracking (HCR) process has a
higher tolerable concentrations of metal contents than that of gas
turbine fuel (GTF) or the like, the yield of deasphalted oil M4
produced in the solvent deasphalting process 3 can be improved
without accompanying a load of hydrodemetalizating/desulfurizing
process, thereby suppressing the production of asphaltene (pitch)
M5 from the residue M2.
[0050] Now referring to the process flow diagram of FIG. 1, in case
the deasphalted oil M4 obtained in the solvent deasphalting process
3 includes relatively low concentrations of metals and sulfur, and
is mixed with a part of the HDMS refined oil that includes further
lower concentrations of metals and sulfur so that the requirements
for the feed stock properties for fluid catalyst cracking (FCC) or
hydrocracking (HCR) process are satisfied, a part thereof may be
sent through the bypass shown by reference numeral 12 in FIG. 1 to
be mixed with a part of the HDMS refined oil M6, instead of being
subjected to the hydrodemetalizating/desulfurizing process 4,
thereby to produce intermediate oil products used as the feed for
fluid catalytic cracking (FCC) process or the feed for
hydrocracking (HCR) process.
[0051] [Second Embodiment]
[0052] FIG. 2 is a process flow diagram explaining the second
embodiment of the oil refining method according to the present
invention, wherein gas turbine fuel (GTF) and feed for fluid
catalytic cracking (FCC) process or feed for hydrocracking (HCR)
process are produced at the same time from a feed oil, similarly to
the first embodiment shown in FIG. 1.
[0053] The second embodiment is different from the first embodiment
shown in FIG. 1 mainly in that a vacuum fractional distillation
process 6 is provided to follow the
hydrodemetalizating/desulfurizing process 4, so as to process the
HDMS refined oil M6 that has been obtained in a vacuum distillation
and separate it into vacuum gas oil M7 and vacuum residue M8
through a vacuum distillation process. In other words, with the oil
refining method shown in FIG. 2, the HDMS refined oil M6 obtained
similarly to the example shown in FIG. 1 is distilled in a vacuum
in the vacuum fractional distillation process 6.
[0054] In the vacuum fractional distillation process, the HDMS
refined oil M6 is introduced into a vacuum distillation tower where
the HDMS refined oil M6 is distilled and separated into a
low-boiling point component and a high-boiling point component,
while the vacuum gas oil M7 having low boiling point is obtained
from the top of the tower and the vacuum residue M8 having a high
boiling point is obtained from the bottom of the tower.
[0055] Since the vacuum fractional distillation process described
above is applied, extraction ratio for the vanadium content
included in the deasphalted oil M4 to the vanadium (V) content
included in the residue M2 used as the feed oil is 30% or lower.
This makes it possible to improve the yield of the oil products
without applying a large load of a
hydrodemetalizating/desulfurizing process.
[0056] The demetalizing and desulfurizing conditions for the HDMS
refined oil M6 obtained by hydrodemetalizating/desulfurizing
process of the deasphalted oil M4 are selected so as to control the
vanadium (V) content of the HDMS refined oil M6 to 20 wt ppm or
lower, preferably 10 wt ppm or lower, and the sulfur content is
desirably controlled to 0.5 wt % or lower, preferably 0.3 wt % or
lower.
[0057] Moreover, it is desirable to set the vanadium content of the
vacuum gas oil obtained by vacuum distillation of the HDMS refined
oil M6 to 1 wt ppm or lower.
[0058] Following the process described above, at least a part of
the vacuum gas oil M7 obtained in the vacuum fractional
distillation process 6 and at least a part of the hydrorefined oil
M3 obtained in the hydrorefining process 2 are mixed in the second
mixing process 7 thereby to obtain one of the oil products.
[0059] In order to produce gas turbine fuel (GTF) as the oil
product obtained in the second mixing process 7, the mixing
condition is set so as to achieve the vanadium (V) content of 0.5
wt ppm or lower similarly to the example shown in FIG. 1. In this
case, the mix proportion is properly adjusted according to the
vanadium content of the vacuum gas oil M7 similarly to the previous
example. When vanadium (V) content of the vacuum gas oil M7 is 0.5
wt ppm or lower, this may be used as gas turbine fuel (GTF) without
adding the hydrorefined oil M3 thereto.
[0060] The remainder of the vacuum gas oil M7, the vacuum residue
M8 obtained by vacuum distillation, and remainder of the HDMS
refined oil M6 that is not fed to the vacuum fractional
distillation process 6 are used individually or in an appropriate
combination thereof thereby to provide an intermediate oil product
used as the feed for fluid catalytic cracking (FCC) process or the
feed for hydrocracking (HCR) process.
[0061] With the oil refining method described above, since the HDMS
refined oil M6 is subjected to vacuum distillation and is separated
into the vacuum gas oil M7 and the vacuum residue M8 that include
no significant metal content or residual carbon content, by making
use of the range of boiling points of the distillation properties
in the vacuum fractional distillation process 6, relatively high
concentrations of vanadium, metals and residual carbon can be
allowed for the HDMS refined oil M6 itself, thus improving the
yield of deasphalted oil M4 in the solvent deasphalting process 3,
and therefore it is possible to suppress the production of
asphaltene (pitch) M5 from the residue M2.
[0062] With regard to the deasphalted oil M4 obtained in the
solvent deasphalting process 3, too, in case the vanadium (V)
content of M4 is sufficiently low, a part of the M4 may be
introduced into the bypass 12 to be mixed with a part of the vacuum
residue M8 sent from the vacuum fractional distillation process 6,
instead of being subjected to the hydrodemetalizating/desulfurizing
process 4, thereby to produce intermediate oil products used as the
feed for fluid catalytic cracking (FCC) or hydrocracking (HCR)
process. The HDMS refined oil M6 obtained in the
hydrodemetalizating/desulfurizing process 4 may also be introduced
into the bypass 12 to be mixed with the vacuum residue M8 sent from
the vacuum fractional distillation process 6 thereby to produce
intermediate oil products used as the feed for fluid catalytic
cracking (FCC) or hydrocracking (HCR) process.
[0063] [Third Embodiment]
[0064] FIG. 3 is a process flow diagram explaining the third
embodiment of the present invention, wherein gas turbine fuel (GTF)
and feed for fluid catalytic cracking (FCC) or hydrocracking (HCR)
process are produced at the same time from a feed oil, similarly to
the example shown in FIG. 1.
[0065] The third embodiment is different from the first embodiment
shown in FIG. 1 mainly in that fractional distillation process 1 is
followed by a vacuum fractional distillation process 20 wherein the
residue M2 is separated into vacuum gas oil M11 and vacuum residue
M12 by vacuum distillation, a solvent deasphalting process 21
wherein the vacuum residue M12 is separated into deasphalted oil
M13 and asphaltene (pitch) M14 by solvent deasphalting, and a
hydrodemetalizating/desulfurizing process 22 wherein a mixture of
the deasphalted oil M13 and the vacuum gas oil M11 is subjected to
hydrodemetalizating/desulfurizing process thereby to produce HDMS
refined oil M15 .
[0066] With the oil refining method shown in FIG. 3, the residue M2
obtained similarly to the example shown in FIG. 1 is distilled in a
vacuum in the vacuum fractional distillation process 20.
[0067] In the vacuum fractional distillation process, the residue
M2 is introduced into a vacuum distillation tower where the residue
M2 is distilled and separated into a low-boiling point component
and a high-boiling point component, while the vacuum gas oil M11
having the lower boiling point is obtained from the top of the
tower and the vacuum residue M12 having the higher boiling point is
obtained from the bottom of the tower.
[0068] Following the vacuum fractional distillation process 20, the
vacuum residue M12 thus obtained is subjected to the solvent
deasphalting process 21 and is separated into deasphalted oil M13
and asphaltene (pitch) M14 . Although the solvent deasphalting
process is similar to those in the examples shown in FIG. 1 and
FIG. 2, the desirable upper limit of the extraction ratio of
vanadium for the deasphalted oil M13 obtained from the vacuum
residue by solvent deasphalting process becomes lower in
correspondence to the concentrations of metals, residual carbon and
sulfur that are higher than those of the residue M2, and therefore
the extraction ratio is preferably controlled to 15%.
[0069] Then the deasphalted oil M13 and the vacuum gas oil M11 thus
obtained are mixed and the mixture is subjected to the
hydrodemetalizating/desulfurizing process, thereby to obtain the
HDMS refined oil M15 . The demetalizing and desulfurizing
conditions for the HDMS refined oil M15 thus obtained are
preferably selected so as to achieve the vanadium (V) content of 2
wt ppm or lower, preferably 1 wt ppm or lower, and a sulfur content
of 0.5 wt ppm or lower, preferably 0.3 wt ppm or lower.
[0070] Then a part of the HDMS refined oil M15 obtained in the
hydrodemetalizating/desulfurizing process 22 and at least a part of
the hydrorefined oil M3 obtained in the hydrorefining process 2 are
mixed in the third mixing process 23, thereby to obtain gas turbine
fuel (GTF) as one of the oil products that has vanadium (V) content
of 0.5 wt ppm or lower.
[0071] Of the HDMS refined oil M15 obtained in the
hydrodemetalizating/des- ulfurizing process 22, the remainder that
is not subjected to the third mixing process 23 may be used as an
intermediate oil product to be fed to fluid catalytic cracking
(FCC) or hydrocracking (HCR) process.
[0072] In case the deasphalted oil M13 and the vacuum gas oil M11
include significantly different concentrations of metals, residual
carbon and sulfur and require reaction conditions, particularly
partial pressure of hydrogen, that are significantly different from
each other, the M13 and the M11 may be, instead of being mixed,
subjected to hydrodemetalizating/desulfurizing process in separate
reactors each under optimum conditions, and then mixed or at least
part of the vacuum gas oil M11 that has been subjected to
hydrodemetalizating/desulfurizing process and at least a part of
the hydrorefined oil M3 may be mixed thereby to obtain gas turbine
fuel (GTF) that has vanadium (V) content of 0.5 wt ppm or
lower.
[0073] According to the oil refining method described above, since
a part of the HDMS refined oil M15 and at least a part of the
hydrorefined oil M3 are mixed in the third mixing process 23,
vanadium (V) content of the mixture oil thus obtained becomes
sufficiently low, and it is possible to obtain gas turbine fuel as
one of the petroleum product. It is also possible to obtain an
intermediate oil product having sufficiently low metal content
(V+Ni) that can be used as the feed for a fluid catalytic cracking
or a hydrocracking process, even from the remainder of HDMS refined
oil M15 obtained from a mixture of the vacuum gas oil M7 and the
deasphalted oil M13 by hydrodemetalizating/desulfurizing process,
and therefore a plurality of oil products having a high added value
can be produced at the same time.
[0074] Since the intermediate oil product used as the feed for
fluid catalytic cracking (FCC) or hydrocracking (HCR) process has a
higher tolerable concentrations of metal contents than that of gas
turbine fuel (GTF) or the like, the yield of deasphalted oil M13 in
the solvent deasphalting process 21 can be improved by producing
the gas turbine fuel and the feed for a fluid catalytic cracking or
a hydrocracking process at the same time, thereby suppressing the
production of asphaltene (pitch) M14 from the vacuum residue M12
.
[0075] Now fourth through sixth embodiments that can be preferably
applied when low-sulfur crude is used as the feed oil will be
described below. The low-sulfur crude in this specification refers
to crude oil such as Arabian Light, Iranian Light, Iranian Heavy,
Marban, and other crude oil that includes sulfur content in a
concentration similar to or lower than those of the former species,
specifically crude oils including a sulfur content of 2.0 wt % or
lower.
[0076] The hydrorefining process (HT process) 2 of the first
embodiment that deals with heavy crude oil is omitted in the
following embodiments because low-sulfur crude is used. In other
respects, basically the same processes as those of the first
embodiment are carried out. In the description that follows,
processes identical to those of the first embodiment will be
indicated by adding a letter A to the end of the reference numeral
used in the first embodiment.
[0077] [Fourth Embodiment]
[0078] FIG. 4 is a process flow diagram showing the fourth
embodiment of the present invention. In the fourth embodiment, the
low-sulfur crude mentioned above is used as the feed oil which is
subjected to a fractional distillation process 1A and is distilled
similarly to the prior art so as to be separated into a distillate
M1A consisting of low-boiling point oil and a residue M2A having a
higher boiling point. An apparatus similar to that of the first
embodiment may be used.
[0079] The distillate M1A obtained in the fractional distillation
process 1A is separated into distillates M3 A, M3 A' by a flasher
30.
[0080] The residue M2A obtained in the fractional distillation
process 1A is deasphalted with a solvent in a solvent deasphalting
process (SDA process) 3A, thereby to obtain deasphalted oil (DAO)
M4A as an extract and asphaltene (pitch) M5A.
[0081] In the solvent deasphalting process, first the residue 2A is
put into contact with the solvent in counterflow in a solvent
extraction tower and is separated into deasphalted oil and
asphaltene (pitch) that includes metal and residual carbon in high
concentrations. The deasphalted oil is recovered together with the
solvent through the top of the tower, and the solvent is separated
from the recovered material in super-critical state. Asphaltene
(pitch) is recovered together with the solvent through the bottom
of the tower, and the solvent in the recovered material is removed
by evaporation.
[0082] In case the refining process that follows the solvent
deasphalting process 3A includes only the
hydrodemetalizating/desulfurizing process 4A, it is preferable to
control the extraction ratio of the solvent deasphalting process so
that vanadium (V) content in the deasphalted oil M4A becomes 25 wt
ppm or lower.
[0083] At least a part of the deasphalted oil M4A obtained in the
solvent deasphalting process 3A is introduced into the
hydrodemetalizating/desulf- urizing process (HDMS process) 4A, so
that the part of the deasphalted oil is demetalized and
desulfurized by hydrogenation in the presence of hydrogen and a
catalyst thereby to obtain the HDMS refined oil M6A that has been
demetalized and desulfurized. Since the hydrodemetalizating/desu-
lfurizing process is basically the same as the hydrorefining
process that deals with heavy crude oil described previously, and
the description thereof will be omitted.
[0084] Hydrodemetalizing and desulfurizing conditions are
preferably selected so as to obtain the HDMS refined oil M6A having
vanadium (V) content of 2 wt ppm or lower, preferably 1 wt ppm or
lower, and a sulfur content of 0.5 wt % or lower, preferably 0.3 wt
% or lower.
[0085] A part of the HDMS refined oil M6A obtained in the
hydrodemetalizating/desulfurizing process 4A and at least a part of
the distillate M3 A are mixed in the fourth mixing process 5A
thereby to obtain a petroleum product.
[0086] In order to produce gas turbine fuel (GTF) as the oil
product obtained in the fourth mixing process 5A, the mix
proportion is set so as to achieve a vanadium (V) content of 0.5 wt
ppm or lower in the petroleum product. In case the vanadium content
of the HDMS refined oil M6A is 1 wt ppm and the vanadium content of
the distillate M3 A is 0 wt ppm, for example, rate of the HDMS
refined oil M6A to the distillate M3 A is set to 1:1 or less (that
is, the smaller proportion of the HDMS refined oil M6A) in volume
proportion for mixing.
[0087] Of the HDMS refined oil M6A obtained in the
hydrodemetalizating/des- ulfurizing process 4A, the remainder
thereof that is not subjected to the fourth mixing process 5A is
used as an intermediate oil product to be fed to the fluid
catalytic cracking (FCC) or hydrocracking (HCR) process. Of the
hydrorefined oil M3, the remainder thereof that is not subjected to
the first mixing process 5A may be used as an oil product M3 A'
such as naphtha, gasoline, kerosene or gas oil.
[0088] According to the oil refining method described above, since
a part of the HDMS refined oil M6A and at least a part of the
hydrorefined oil M3 A are mixed, it is possible to obtain an oil
product that has a sufficiently low vanadium (V) content such as
gas turbine fuel. It is also possible to produce an intermediate
oil product having a relatively low metal content (V+Ni) that can
be used as the feed for fluid catalytic cracking (FCC) or
hydrocracking (HCR) process from the remainder of the HDMS refined
oil M6A, and efficiently produce a plurality of oil products having
high added values.
[0089] Since the intermediate oil product used as the feed for
fluid catalytic cracking (FCC) or hydrocracking (HCR) process has a
higher tolerable concentrations of metal contents than that of gas
turbine fuel (GTF) or the like, the yield of deasphalted oil M4A
produced in the solvent deasphalting process 3A can be improved
without accompanying load of hydrodemetalizating/desulfurizing
process, thereby suppressing the production of asphaltene (pitch)
M5A from the residue M2A.
[0090] Now referring to the process flow diagram of FIG. 4, in case
the deasphalted oil M4A obtained in the solvent deasphalting
process 3A includes relatively low concentrations of metals and
sulfur, and is mixed with a part of the HDMS refined oil that
includes further lower concentrations of metals and sulfur so as to
satisfy the requirements for the feed stock properties for fluid
catalytic cracking (FCC) or hydrocracking (HCR) process, a part
thereof may be sent through the bypass shown by reference numeral
12A in FIG. 4 thereby to be mixed with a part of the HDMS refined
oil M6A, instead of being subjected to the
hydrodemetalizating/desulfurizing process 4A, thereby to produce an
intermediate oil product used as the feed for the fluid catalytic
cracking (FCC) process or the feed for the hydrocracking (HCR)
process.
[0091] [Fifth Embodiment]
[0092] FIG. 5 is a process flow diagram explaining the fifth
embodiment of the oil refining method according to the present
invention, in which gas turbine fuel (GTF) and feed for fluid
catalytic cracking (FCC) process or feed for hydrocracking (HCR)
process are produced at the same time from a feed oil, similarly to
the embodiment shown in FIG. 4.
[0093] This embodiment is different from the embodiment shown in
FIG. 4 mainly in that vacuum fractional distillation process 6A is
provided to follow the hydrodemetalizating/desulfurizing process
4A, so as to process the HDMS refined oil M6A in a vacuum
distillation and separate it into vacuum gas oil M7A and vacuum
residue M8A.
[0094] In other words, with the oil refining method shown in FIG.
5, the HDMS refined oil M6A obtained similarly to the example shown
in FIG. 4 is distilled in a vacuum in the vacuum fractional
distillation process 6A.
[0095] In the vacuum fractional distillation process, the HDMS
refined oil M6A is introduced into a vacuum distillation tower
where the HDMS refined oil M6A is distilled and separated into a
low-boiling point component and a high-boiling point component,
while the vacuum gas oil M7A having the lower boiling point is
obtained from the top of the tower and the vacuum residue M8A
having the higher boiling point is obtained from the bottom of the
tower.
[0096] Since the vacuum fractional distillation process described
above is carried out, extraction ratio of the deasphalted oil M4A
obtained in the solvent deasphalting process can be controlled so
that desirable upper limit of the vanadium (V) content is set to,
for example, 50 wt ppm. Thus the extraction ratio can be made
higher and the yield of recovering the oil products can be
improved.
[0097] The demetalizing and desulfurizing conditions for the HDMS
refined oil M6A obtained from the deasphalted oil M4A through the
hydrodemetalizating/desulfurizing process are preferably selected
so as to achieve the vanadium (V) content of 20 wt ppm or lower,
preferably 10 wt ppm or lower, while the sulfur content is
desirably set to 0.5 wt % or lower, preferably 0.3 wt % or
lower.
[0098] Moreover, it is desirable to set the vanadium content of the
vacuum gas oil obtained by vacuum distillation of the HDMS refined
oil M6A to 1 wt ppm or lower.
[0099] Following the process described above, at least a part of
the vacuum gas oil M7A obtained in the vacuum fractional
distillation process 6A and the distillate M3 A are mixed in the
fifth mixing process 7A thereby to obtain one of the oil
products.
[0100] In order to produce gas turbine fuel (GTF) as the oil
product obtained in the fifth mixing process 7A, vanadium (V)
content is controlled to 0.5 wt ppm or lower similarly to the
example shown in FIG. 4. In that case, the mix proportion is
adjusted according to the vanadium content of the vacuum gas oil
M7A similarly to the previous example. When vanadium (V) content of
the vacuum gas oil M7A is 0.5 wt ppm or lower, this may be used as
gas turbine fuel (GTF) without adding the distillate M3 A.
[0101] The remainder of the vacuum gas oil M7A, the vacuum residue
M8A obtained by vacuum distillation and remainder of the HDMS
refined oil M6A that is not fed to the vacuum fractional
distillation process 6A are used individually or in an appropriate
combination thereof as an intermediate oil product to be used as
the feed for fluid catalytic cracking (FCC) process or the feed for
hydrocracking (HCR) process.
[0102] With the oil refining method described above, since the HDMS
refined oil M6A is subjected to vacuum distillation in the vacuum
fractional distillation process 6A so as to separate into the
vacuum gas oil M7A and the vacuum residue M8A that include no
significant metal content and residual carbon content by making use
of the range of boiling points of the distillation properties,
relatively high concentrations of vanadium, metals and residual
carbon can be allowed for the HDMS refined oil M6A itself, thus
improving the yield of deasphalted oil M4A in the solvent
deasphalting process 3A, and therefore it is possible to suppress
the production of asphaltene (pitch) M5A from the residue M2A.
[0103] With regard to the deasphalted oil M4A obtained in the
solvent deasphalting process 3A, too, in case the vanadium (V)
content of M4 is sufficiently low, a part of the M4 may be
introduced into the bypass 12A to be mixed with the vacuum residue
M8A sent from the vacuum fractional distillation process 6A,
instead of being subjected to the hydrodemetalizating/desulfurizing
process 4A, thereby to produce intermediate oil products used as
the feed for fluid catalytic cracking (FCC) or hydrocracking (HCR)
process. The HDMS refined oil M6A obtained in the
hydrodemetalizating/desulfurizing process 4A may also be introduced
into the bypass 12A to be mixed with the vacuum residue M8A sent
from the vacuum fractional distillation process 6A thereby to
produce intermediate oil products used as the feed for fluid
catalytic cracking (FCC) or hydrocracking (HCR) process.
[0104] [Sixth Embodiment]
[0105] FIG. 6 is a process flow diagram explaining the sixth
embodiment of the oil refining method according to the present
invention, for a case of producing gas turbine fuel (GTF) and feed
for fluid catalytic cracking (FCC) process or feed for
hydrocracking (HCR) process at the same time from a feed oil,
similarly to the embodiment shown in FIG. 4.
[0106] This embodiment is different from the embodiment shown in
FIG. 4 mainly in that the fractional distillation process 1A is
followed by a vacuum fractional distillation process 20A wherein
the residue M2A is separated into vacuum gas oil M11 A and vacuum
residue M12 A by vacuum distillation, a solvent deasphalting
process 21A wherein the vacuum residue M12 A is separated into
deasphalted oil M13 A and asphaltene (pitch) M14 A by solvent
deasphalting, and a hydrodemetalizating/desulfur- izing process 22A
wherein a mixture of the deasphalted oil M13 A and the vacuum gas
oil M11 A is subjected to hydrodemetalizating/desulfurizing process
thereby to produce HDMS refined oil M15 A.
[0107] With the oil refining method shown in FIG. 6, the residue
M2A obtained similarly to the example shown in FIG. 4 is distilled
in a vacuum in the vacuum fractional distillation process 20A.
[0108] In the vacuum fractional distillation process, the residue
M2A is introduced into a vacuum distillation tower where the M2A is
distilled and separated into a low-boiling point component and a
high-boiling point component, while the vacuum gas oil M11 A having
the lower boiling point is obtained from the top of the tower and
the vacuum residue M12 A having the higher boiling point is
obtained from the bottom of the tower.
[0109] The vacuum fractional distillation process 20A is followed
by the solvent deasphalting process 21A where the vacuum residue
M12 A obtained in the former process is separated into deasphalted
oil M13 A and asphaltene (pitch) M14 A. While the vacuum fractional
distillation process is similar to the cases shown in FIG. 4 and
FIG. 5, the extraction ratio of the deasphalted oil M13 A obtained
in the solvent deasphalting process of the vacuum residue is
controlled so that the desirable upper limit of the vanadium (V)
content rises to, for example, 70 wt ppm in correspondence to the
concentrations of metals, residual carbon, and sulfur in M13 A that
are higher than those of the residue M2A.
[0110] Then the deasphalted oil M13 A and the vacuum gas oil M11 A
thus obtained are mixed and the mixture is subjected to the
hydrodemetalizating/desulfurizing process, thereby to obtain the
HDMS refined oil M15 A. The demetalizing and desulfurizing
conditions for the HDMS refined oil M1SA thus obtained are
preferably selected so as to achieve the vanadium (V) content of 2
wt ppm or lower, preferably 1 wt ppm or lower, and a sulfur content
of 0.5 wt % or lower, preferably 0.3 wt % or lower.
[0111] Then a part of the HDMS refined oil M15 A obtained in the
hydrodemetalizating/desulfurizing process 22A and the distillate M3
A are mixed in the sixth mixing process 23A thereby to obtain gas
turbine fuel (GTF) as one of the oil product that has vanadium (V)
content of 0.5 wt ppm or lower.
[0112] The remainder of the HDMS refined oil M15 obtained in the
hydrodemetalizating/desulfurizing process 22A that is not fed to
the sixth mixing process 23A may be used as an intermediate oil
product to be used as the feed for the fluid catalytic cracking
(FCC) process or the feed for the hydrocracking (HCR) process.
[0113] In case the deasphalted oil M13 A and the vacuum gas oil M11
A have significantly different concentrations of metals, residual
carbon and sulfur and require reaction conditions, particularly
partial pressure of hydrogen, which are significantly different
from each other, the M13 A and M11 A may be, instead of being
mixed, subjected to hydrodemetalizating/desulfurizing process in
separate reactors each under optimum conditions, and then mixed
with each other, or at least part of the vacuum gas oil M11 A that
has been subjected to the hydrodemetalizating/desulfurizing process
and at least a part of the distillate M3 A are mixed thereby to
obtain gas turbine fuel (GTF) that has vanadium (V) content of 0.5
wt ppm or lower.
[0114] According to the oil refining method described above, since
a part of the HDMS refined oil M15 A and at least a part of the
distillate M3 A are mixed in the sixth mixing process 23A, the
vanadium (V) content of the mixed oil becomes sufficiently low and
it is possible to obtain gas turbine fuel as one of the petroleum
products. It is also possible to produce intermediate oil products
of low metal content (V+Ni) used as the feed for a fluid catalytic
cracking or a hydrocracking process even from the remainder of the
HDMS refined oil M15 A obtained from a mixture of the vacuum gas
oil M7A and the deasphalted oil M13 A by
hydrodemetalizating/desulfurizing process. Thus a plurality of
intermediate oil products having a high added value can be produced
efficiently.
[0115] Since the intermediate oil product used as the feed for
fluid catalytic cracking (FCC) or hydrocracking (HCR) process has
more lenient tolerance for metal contents than gas turbine fuel or
the like, the yield of deasphalted oil M13 A in the solvent
deasphalting process 21A can be improved by producing the gas
turbine fuel (GTF) and feed for the fluid catalytic cracking (FCC)
process or feed for the hydrocracking (HCR) process at the same
time, thereby suppressing the production of asphaltene (pitch) M14
A from the vacuum residue M12 A.
EXPERIMENT EXAMPLES
[0116] Now the present invention will be described below more
specifically by way of experimental examples.
Experimental Example 1
[0117] A plurality of oil products including gas turbine fuel and
intermediate oil products to be used as the feed for a fluid
catalytic cracking or a hydrocracking process were produced as
shown in FIG. 7 by the oil refining method shown in FIG. 1.
[0118] An ultra heavy crude (Orinoco oil) having an API gravity of
8.5, a sulfur content of 3.67 wt % and a vanadium content of 393 wt
ppm was used as feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1) in a topper thereby to
obtain distillate M1 and residue M2. The yield of the distillate M1
was 15.9 wt % of the feed oil and the sulfur content was 2.41 wt %.
The yield of the residue M2 was 83.5 wt % of the feed oil, while
the sulfur content was 4.07 wt % and the vanadium content was 472
wt ppm.
[0119] Then the distillate M1 thus obtained was desulfurized in
hydrorefining process 2 in the presence of hydrogen and catalyst,
thereby to obtain hydrorefined oils M3, M3 '. M3 ' was used as a
petroleum product, naphtha, without applying further processing.
The yield of the hydrorefined oil M3 was 13.0 wt % of the feed oil
and the sulfur content was 0.02 wt %. The yield of naphtha M3 ' was
2 wt % of the feed oil.
[0120] Apart from the hydrorefining process, the residue M2 was
subjected to the solvent deasphalting process 3 in a solvent
extraction tower using isobutane as the solvent, thereby to obtain
deasphalted oil M4 with 65% extraction ratio and asphaltene (pitch)
M5 as the residue. The ratio of the solvent to the residue M2
(solvent/M2) in the solvent deasphalting process was set to 8. The
yield of the deasphalted oil M4 was 54.3 wt % of the feed oil,
while the sulfur content was 3.60 wt %, the vanadium content was 66
wt ppm, and the extraction ratio was 14%. The yield of the
asphaltene (pitch) M5 was 29.2 wt % of the feed oil.
[0121] The deasphalted oil M4 thus obtained was introduced into a
reactor filled with a hydrodemetalizing catalyst and a
hydrodesulfurizing catalyst in a ratio of 3:7 in volume proportion,
thereby to obtain the HDMS refined oil M6 through
hydrodemetalizating/desulfurizing process 4 in the presence of
hydrogen and the catalysts. The process conditions were set to
partial pressure of hydrogen of 100 atm, and the H.sub.2 to oil
ratio of 800 Nl/l. The LHSV was 0.7/hr and the reaction temperature
was 370.degree. C. The yield of the HDMS refined oil M6 was 51 wt %
of the feed oil, the sulfur content was 0.4 wt %, and the vanadium
content was 0.7 wt ppm.
[0122] Then 15 wt % (in terms of yield from the fed oil) of the
HDMS refined oil M6 thus obtained was mixed with the hydrorefined
oil M3 (first mixing process 5) thereby to produce a gas turbine
fuel (GTF) with a yield of 28 wt % of the feed oil, a sulfur
content of 0.22 wt %, and a vanadium content of 0.38 wt ppm. The
remainder, namely 36 wt % (in terms of yield from the fed oil) of
the HDMS refined oil M6 was used as a feed stock for the fluid
catalyst cracking (FCC) process or a feed stock for the
hydrocracking (HCR) process without applying further
processing.
Experimental Example 2
[0123] A plurality of oil products including gas turbine fuel and
intermediate oil products to be used as the feed for a fluid
catalytic cracking or a hydrocracking process were produced as
shown in FIG. 8 by the oil refining method shown in FIG. 2.
[0124] The ultra heavy crude (Orinoco oil) having an API gravity of
8.5, a sulfur content of 3.67 wt % and a vanadium content of 393 wt
ppm was used as feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1) in a topper thereby to
obtain distillate M1 and residue M2. The yield of the distillate M1
was 15.9 wt % of the feed oil and the sulfur content was 2.41 wt %.
The yield of the residue M2 was 83.5 wt % of the feed oil, while
the sulfur content was 4.07 wt % and the vanadium content was 472
wt ppm.
[0125] Then the distillate M1 thus obtained was desulfurized in
hydrorefining process 2 in the presence of hydrogen and catalyst,
thereby to obtain hydrorefined oils M3, M3 '. M3 ' was used as a
petroleum product, naphtha, without applying further processing.
The yield of the hydrorefined oil M3 was 13.0 wt % of the feed oil
and the sulfur content was 0.02 wt %. The yield of naphtha M3 ' was
2 wt % of the feed oil.
[0126] Apart from the hydrorefining process, the residue M2 was
subjected to the solvent deasphalting process 3 in a solvent
extraction tower using pentane as the solvent, thereby to obtain
deasphalted oil M4 with a 76.6% extraction ratio and asphaltene
(pitch) M5 as the residue. The ratio of the solvent to the residue
M2 (solvent/M2) in the solvent deasphalting process was set to 8.
The yield of the deasphalted oil M4 was 64 wt % of the feed oil,
the sulfur content was 3.9 wt %, the vanadium content was 130 wt
ppm and the extraction ratio was 27.5%. The yield of the asphaltene
(pitch) M5 was 19.5 wt % of the feed oil.
[0127] The deasphalted oil M4 thus obtained was introduced into a
reactor filled with a hydrodemetalizing catalyst and a
hydrodesulfurizing catalyst in a ratio of 5:5 in volume proportion,
thereby to obtain the HDMS refined oil M6 through
hydrodemetalizating/desulfurizing process 4 in the presence of
hydrogen and the catalysts. The process conditions were set to
partial pressure of hydrogen of 100 atm, H.sub.2 to oil ratio of
800 Nl/l. The LHSV was 0.5/hr and reaction temperature was
370.degree. C. The yield of the HDMS refined oil M6 was 59 wt % of
the feed oil, the sulfur content was 0.45 wt %, and the vanadium
content was 8 wt ppm.
[0128] Then the HDMS refined oil M6 thus obtained was distilled in
a vacuum (vacuum fractional distillation process 6) thereby to
obtain a vacuum gas oil (VGO) M7 and the vacuum residue M8. The
yield of the vacuum gas oil M7 was 25 wt % of the feed oil, the
sulfur content was 0.24 wt %, and the vanadium content was 0.3 wt
ppm.
[0129] All of the vacuum gas oil M7 was mixed with the hydrorefined
oil M3 (second mixing process 7) thereby to produce gas turbine
fuel (GTF) with a yield of 38 wt % of the feed oil, a sulfur
content of 0.16 wt %, and a vanadium content of 0.19 wt ppm. The
vacuum residue M8 obtained in the vacuum fractional distillation
process was used as a feed stock for the fluid catalyst cracking
(FCC) process or a feed stock for the hydrocracking (HCR) process
without applying further processing. The feed stock for the fluid
catalyst cracking (FCC) process or the feed stock for the
hydrocracking (HCR) process may also be obtained by mixing a part
of the deasphalted oil M4 or a part of the HDMS refined oil M6 with
the vacuum residue M8. The feed stock for the fluid catalyst
cracking (FCC) process or the feed stock for the hydrocracking
(HCR) process that is obtained in this way showed yield of 34 wt %
of the feed oil, a sulfur content of 0.60 wt %, and a vanadium
content of 13.7 wt ppm.
Experimental Example 3
[0130] A plurality of oil products including gas turbine fuel and
intermediate oil products to be used as the feed for a fluid
catalytic cracking or a hydrocracking process were produced as
shown in FIG. 9 by the oil refining method shown in FIG. 3.
[0131] An ultra heavy crude (Arabian heavy) having an API gravity
of 28, a sulfur content of 2.9 wt % and a vanadium content of 69 wt
ppm was used as feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1) in a topper thereby to
obtain distillate M1 and residue M2. The yield of the distillate M1
was 41 wt % of the feed oil and the sulfur content was 0.79 wt %.
The yield of the residue M2 was 58.5 wt % of the feed oil, while
the sulfur content was 4.72 wt % and the vanadium content was 117
wt ppm.
[0132] Then the residue M2 thus obtained was subjected to vacuum
fractional distillation process 20 thereby to obtain a vacuum gas
oil M11 and vacuum residue M12 . The yield of the vacuum gas oil
M11 was 28.2 wt % of the feed oil, the sulfur content was 3.37 wt
%, and the vanadium content was 1.5 wt ppm. The yield of the vacuum
residue M12 was 30.6 wt % of the feed oil, the vanadium content was
223 wt ppm, (V+Ni) content was 294 wt ppm, residual carbon content
was 24.4% and the sulfur content was 6.04 wt %.
[0133] Fractions of LPG, naphtha, kerosene, and gas oil obtained
from the distillate M1 were refined separately by hydrogenation
(hydrorefining process 2) thereby to obtain corresponding
hydrorefined oils (light fractions) M3, M3 '. The yield of the
hydrorefined oil M3 was 20.3 wt % of the feed oil and the sulfur
content was 0.05 wt %. The yield of the gasoline, kerosene, and gas
oil from the hydrorefined oil M3 ' was 6.0 wt % and 13.7 wt %,
respectively, of the feed oil.
[0134] Apart from the hydrorefining process, the vacuum residue M12
was subjected to the solvent deasphalting process 21 in a solvent
extraction tower using isobutane as the solvent, thereby to obtain
deasphalted oil M13 with a 60% extraction ratio and asphaltene
(pitch) M14 as the residue. The ratio of the solvent to the vacuum
residue M12 (solvent/M12 ) in the solvent deasphalting process was
set to 8. The yield of the deasphalted oil M13 was 18.4 wt % of the
feed oil, the sulfur content was 4.62 wt %, the vanadium content
was 22 wt ppm and the extraction ratio was 19%. The yield of the
asphaltene (pitch) M14 was 12.2 wt % of the feed oil.
[0135] A mixture of the deasphalted oil M13 and the vacuum gas oil
M11 was introduced into a reactor filled with a hydrodemetalizing
catalyst and a hydrodesulfurizing catalyst in a ratio of 1:9 in
volume proportion, thereby to obtain the HDMS refined oil M15
through hydrodemetalizating/desulfurizing process 4 in the presence
of hydrogen and the catalysts. The process conditions were set to
partial pressure of hydrogen of 90 atm, the H.sub.2 to oil ratio of
800 Nl/l. The LHSV was 0.7/hr and reaction temperature was
370.degree. C. The yield of the HDMS refined oil M15 was 44 wt % of
the feed oil, the sulfur content was 0.6 wt %, and the vanadium
content was 1.0 wt ppm.
[0136] Then 15 wt % (in proportion to the fed oil) of the HDMS
refined oil M15 thus obtained was mixed with the hydrorefined oil
M3 thereby to produce gas turbine fuel that included sulfur content
of 0.28 wt %, and a vanadium content of 0.42 wt ppm with a yield of
45 wt % of the feed oil. The remainder, specifically, 29 wt % of
the HDMS refined oil was used as a feed stock for the fluid
catalyst cracking (FCC) process or hydrocracking (HCR) process.
[0137] Now experimental examples that used low-sulfur content crude
oil will be described below.
Experimental Example 4
[0138] A plurality of oil products including gas turbine fuel and
intermediate oil products to be used as the feed for a fluid
catalytic cracking or a hydrocracking process were produced as
shown in FIG. 10 by the oil refining method shown in FIG. 4.
[0139] A low-sulfur content crude oil (Arabian light) having a
sulfur content of 1.79 wt % and a vanadium content of 13.5 wt ppm
was used as feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1A) in a topper thereby
to obtain distillate M1A and residue M2A. The yield of the
distillate M1A was 53.5 wt % of the feed oil and the sulfur content
was 0.63 wt %. The yield of the residue M2A was 45.4 wt % of the
feed oil, while the sulfur content was 3.20 wt % and the vanadium
content was 30.0 wt ppm.
[0140] The distillate M1A thus obtained was separated in a flasher
30 thereby to obtain distillates M3 A, M3 A'. M3 ' was used as a
petroleum product, naphtha, without applying further processing.
The yield of the distillate M3 A was 50.9 wt % of the feed oil and
the sulfur content was 0.66 wt %. The yield of naphtha M3 ' was 2.6
wt % of the feed oil.
[0141] The residue M2A was subjected to the solvent deasphalting
process 3A in a solvent extraction tower using isobutane as the
solvent, thereby to obtain deasphalted oil M4A with 65% extraction
ratio and asphaltene (pitch) M5A as the residue. The ratio of the
solvent to the residue M2A (solvent/M2A) in the solvent
deasphalting process was set to 8. The yield of the deasphalted oil
M4A was 38.6 wt % of the feed oil, the sulfur content was 2.80 wt
%, and the vanadium content was 5.9 wt ppm. The yield of the
asphaltene (pitch) M5A was 6.8 wt % of the feed oil.
[0142] The deasphalted oil M4A thus obtained was introduced into a
reactor filled with a hydrodemetalizing catalyst and a
hydrodesulfurizing catalyst in a ratio of 1:9 in volume proportion,
thereby to obtain the HDMS refined oil M6A through
hydrodemetalizating/desulfurizing process 4A in the presence of
hydrogen and the catalysts. The process conditions were set to
partial pressure of hydrogen of 100 atm, H.sub.2 to oil ratio of
800 Nl/l. The LHSV was 0.5/hr and the reaction temperature was
370.degree. C. The yield of the HDMS refined oil M6A was 36.3 wt %
of the feed oil, the sulfur content was 0.10 wt %, and the vanadium
content was 0.9 wt ppm.
[0143] Then 22.7 wt % (in terms of yield from the fed oil) of the
HDMS refined oil M6A thus obtained was mixed with the distillate M3
A (fourth mixing process 5A) thereby to produce gas turbine fuel
(GTF) that included a sulfur content of 0.49 wt %, and a vanadium
content of 0.28 wt ppm with a yield of 73.6 wt % of the feed oil.
The remainder of the HDMS refined oil M6A, namely 13.6 wt % (in
terms of yield from the fed oil) thereof was used as a feed stock
for the fluid catalyst cracking (FCC) process or a feed stock for
the hydrocracking (HCR) process without applying further
processing.
Experimental Example 5
[0144] A plurality of oil products including gas turbine fuel and
intermediate oil products to be used as the feed for a fluid
catalytic cracking or a hydrocracking process were produced as
shown in FIG. 11 by the oil refining method shown in FIG. 5.
[0145] The low-sulfur content crude oil (Arabian light), the same
oil as that used in the fourth experimental example, having a
sulfur content of 1.79 wt % and a vanadium content of 13.5 wt ppm
was used as the feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1A) in a topper thereby
to obtain distillate M1A and residue M2A. The yield of the
distillate M1A was 53.5 wt % of the feed oil and the sulfur content
was 0.63 wt %. The yield of the residue M2A was 45.4 wt % of the
feed oil, while the sulfur content was 3.20 wt % and the vanadium
content was 30.0 wt ppm.
[0146] The distillate M1A thus obtained was separated in the
flasher 30 thereby to obtain distillates M3 A, M3 A'. The
distillate M3 A was used as a petroleum product, naphtha, without
applying further processing. The yield of the distillate M3 A was
50.9 wt % of the feed oil and the sulfur content was 0.66 wt %. The
yield of naphtha M3 A' was 2.6 wt % of the feed oil.
[0147] Apart from the hydrorefining process, the residue M2A was
subjected to the solvent deasphalting process 3A in a solvent
extraction tower using pentane as the solvent, thereby to obtain
deasphalted oil M4A with 65% extraction ratio and asphaltene
(pitch) M5A as the residue. The ratio of the solvent to the residue
M2A (solvent/M2) in the solvent deasphalting process was set to 8.
The yield of the deasphalted oil M4A thus obtained was 38.6 wt % of
the feed oil, the sulfur content was 2.80 wt %, and the vanadium
content was 5.9 wt ppm. The yield of the asphaltene (pitch) M5A was
6.8 wt % of the feed oil.
[0148] The deasphalted oil M4A was introduced into a reactor filled
with a hydrodemetalizing catalyst and a hydrodesulfurizing catalyst
in a ratio of 1:9 in volume proportion, thereby to obtain the HDMS
refined oil M6A through hydrodemetalizating/desulfurizing process
4A in the presence of hydrogen and the catalysts. The process
conditions were set to partial pressure of hydrogen of 100 atm,
H.sub.2 to oil ratio of 800 Nl/l. The LHSV was 0.7/hr and the
reaction temperature was 360.degree. C. The yield of the HDMS
refined oil M6A was 36.3 wt % of the feed oil, the sulfur content
was 0.30 wt %, and the vanadium content was 1.5 wt ppm.
[0149] Then the HDMS refined oil M6A thus obtained was distilled in
a vacuum (vacuum fractional distillation process 6A) thereby to
obtain a vacuum gas oil (VGO) M7A and the vacuum residue M8A. The
yield of the vacuum gas oil M7A thus obtained was 23.0 wt % of the
feed oil, the sulfur content was 0.10 wt %, and the vanadium
content was 0.2 wt ppm.
[0150] All of the vacuum gas oil M7A was mixed with the distillate
M3 A (fifth mixing process 7A) thereby to produce gas turbine fuel
(GTF) that included a sulfur content of 0.49 wt % and a vanadium
content of 0.06 wt ppm, with a yield of 73.9 wt % of the feed oil.
The vacuum residue M8A obtained in the vacuum fractional
distillation process was used as a feed stock for the fluid
catalyst cracking (FCC) process or a feed stock for the
hydrocracking (HCR) process without applying further processing.
The feed stock for the fluid catalyst cracking (FCC) process or the
feed stock for the hydrocracking (HCR) process may also be obtained
by mixing a part of the deasphalted oil M4A or a part of the HDMS
refined oil M6A with the vacuum residue M8A. The feed stock for the
fluid catalyst cracking (FCC) process or the feed stock for the
hydrocracking (HCR) process obtained in this way showed yield of
13.3 wt % of the feed oil, a sulfur content of 0.65 wt %, and a
vanadium content of 3.7 wt ppm.
Experimental Example 6
[0151] A plurality of oil products including gas turbine fuel and
intermediate oil products used as the feed for a fluid catalytic
cracking or a hydrocracking process were produced as shown in FIG.
12 by the oil refining method shown in FIG. 6.
[0152] The low-sulfur content crude oil (Arabian light), the same
oil as that used in the fourth experimental example, having a
sulfur content of 1.79 wt % and a vanadium content of 13.5 wt ppm
was used as feed oil that was first distilled under atmospheric
pressure (fractional distillation process 1A) in a topper thereby
to obtain distillate M1A and residue M2A. The yield of the
distillate M1A was 53.5 wt % of the feed oil and the sulfur content
was 0.63 wt %. The yield of the residue M2A was 45.4 wt % of the
feed oil, while the sulfur content was 3.20 wt % and the vanadium
content was 30.0 wt ppm.
[0153] The residue M2A thus obtained was distilled in a vacuum
(vacuum fractional distillation process 20A) thereby to obtain a
vacuum gas oil M11 A and vacuum residue M12 A. The yield of the
vacuum gas oil M11 A was 30.4 wt % of the feed oil, while the
sulfur content was 2.70 wt % and the vanadium content was 0.1 wt
ppm. The yield of the vacuum residue M12 A was 15.0 wt % of the
feed oil, while the vanadium content was 91.0 wt ppm and the sulfur
content was 4.10 wt %.
[0154] The distillate M1A was separated in the flasher 30 thereby
to obtain distillates M3 A, M3 A'. The distillate M3 A' was used as
one of the petroleum product, naphtha, without applying further
processing. The yield of the distillate M3 A was 50.9 wt % of the
feed oil and the sulfur content was 0.66 wt %. The yield of naphtha
M3 A' was 2.6 wt % of the feed oil.
[0155] Apart from the hydrorefining process, the vacuum residue M12
A was subjected to the solvent deasphalting process 21A in a
solvent extraction tower using isobutane as the solvent, thereby to
obtain deasphalted oil M13 A with a 60% extraction ratio and
asphaltene (pitch) M14 A as the residue. The ratio of the solvent
to the vacuum residue M12 A (solvent/M12 A) in the solvent
deasphalting process was set to 8. The yield of the deasphalted oil
M13 A was 10.5 wt % of the feed oil, the sulfur content was 3.30 wt
%, and the vanadium content was 11.0 wt ppm. The yield of the
asphaltene (pitch) M14 A was 4.5 wt % of the feed oil.
[0156] A mixture of the deasphalted oil M13 A and the vacuum gas
oil M11 A was introduced into a reactor filled with a
hydrodemetalizing catalyst and a hydrodesulfurizing catalyst in a
ratio of 1:9 in volume proportion, thereby to obtain the HDMS
refined oil M15 A through hydrodemetalizating/desulfurizing process
22A in the presence of hydrogen and the catalysts. The process
conditions were set to partial pressure of hydrogen of 100 atm,
H.sub.2 to oil ratio of 800 Nl/l. The LHSV was 0.5/hr and the
reaction temperature was 375.degree. C. The yield of the HDMS
refined oil M15 A was 38.4 wt % of the feed oil, while the sulfur
content was 0.10 wt %, and the vanadium content was 0.9 wt ppm.
[0157] Then 22.7 wt % (in proportion to the fed oil) of the HDMS
refined oil M15 A thus obtained was mixed with the distillate M3 A
thereby to produce gas turbine fuel that included a sulfur content
of 0.49 wt % and a vanadium content of 0.28 wt ppm, with a yield of
73.6 wt % of the feed oil. The remainder of the HDMS refined oil,
namely 15.7 wt % thereof was used as a feed stock for the fluid
catalyst cracking (FCC) process or hydrocracking (HCR) process
without applying further processing.
Industrial Applicability
[0158] The oil refining method according to the present invention
makes it possible to produce, for example, oil product (gas turbine
fuel) having vanadium (V) content of 0.5 wt ppm or lower, and
intermediate oil products having metal (V+Ni) content of 30 wt ppm
or lower that is suitable as the feed stock to be used in the fluid
catalyst cracking (FCC) process or in the hydrocracking (HCR)
process, from a heavy feed oil such as Orinoco tar or a feed oil
having low sulfur content.
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