U.S. patent application number 15/274227 was filed with the patent office on 2017-03-30 for crude oil recovery device.
This patent application is currently assigned to HITACHI, LTD.. The applicant listed for this patent is HITACHI, LTD.. Invention is credited to Kazuhiro ENDOH, Yojiro HAYASHI, Kei HAYASHIDA, Hisashi ISOGAMI, Hideaki KUROKAWA, Tadashi SANO, Masatomo WATANABE.
Application Number | 20170088781 15/274227 |
Document ID | / |
Family ID | 58406804 |
Filed Date | 2017-03-30 |
United States Patent
Application |
20170088781 |
Kind Code |
A1 |
SANO; Tadashi ; et
al. |
March 30, 2017 |
CRUDE OIL RECOVERY DEVICE
Abstract
Provided is a crude oil recovery device for recovering crude oil
from an oil-containing mixture in a stable manner and at low
running cost. The crude oil recovery device for extracting crude
oil from an oil-containing mixture composed of crude oil and both
or one of water and solid, including an extraction tank for mixing
the oil-containing mixture with an extracting solvent, and an
evaporation/liquefaction unit for distilling an extraction solution
after extraction, wherein naphtha, which is a crude oil component
of the oil-containing mixture, is reused as the extracting solvent,
the naphtha being a distillate obtained by distillation of the
extraction solution.
Inventors: |
SANO; Tadashi; (Tokyo,
JP) ; ENDOH; Kazuhiro; (Tokyo, JP) ; HAYASHI;
Yojiro; (Tokyo, JP) ; ISOGAMI; Hisashi;
(Tokyo, JP) ; HAYASHIDA; Kei; (Tokyo, JP) ;
KUROKAWA; Hideaki; (Tokyo, JP) ; WATANABE;
Masatomo; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HITACHI, LTD. |
Tokyo |
|
JP |
|
|
Assignee: |
HITACHI, LTD.
Tokyo
JP
|
Family ID: |
58406804 |
Appl. No.: |
15/274227 |
Filed: |
September 23, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10G 1/045 20130101;
C10G 2300/44 20130101; C10G 2300/201 20130101; C10G 1/002 20130101;
C10G 31/10 20130101 |
International
Class: |
C10G 1/04 20060101
C10G001/04; C10G 31/10 20060101 C10G031/10; C10G 1/00 20060101
C10G001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 29, 2015 |
JP |
2015-190629 |
Claims
1. A crude oil recovery device for extracting crude oil from an
oil-containing mixture composed of water, solid and crude oil,
comprising: an extraction tank for mixing the oil-containing
mixture with an extracting solvent; and an evaporation/liquefaction
unit for distilling an extraction solution after extraction,
wherein naphtha, which is a crude oil component of the
oil-containing mixture, is reused as the extracting solvent, the
naphtha being a distillate obtained by distillation of the
extraction solution.
2. The crude oil recovery device according to claim 1, wherein an
aqueous phase containing solid is removed from the extraction tank
after completion of the extraction, a new oil-containing mixture is
introduced to the extraction tank, and an extraction operation is
performed at least once using a remaining extraction solution.
3. The crude oil recovery device according to claim 1, which is
provided with a reproduced naphtha tank for storing liquefied
reproduced naphtha in a downstream of a liquefaction unit.
4. The crude oil recovery device according to claim 1, which is
provided with a separation tank for separating a mixed solution
into an oil phase and an aqueous phase in a downstream of the
extraction tank.
5. The crude oil recovery device according to claim 1, which is
provided with a centrifugal separator for separating a mixed
solution into an oil phase and an aqueous phase in a downstream of
the extraction tank.
6. The crude oil recovery device according to claim 1, further
comprising a tank for storing the extraction solution containing
crude oil after the extraction, and reusing a part of or all of the
extraction solution as the extracting solvent.
7. The crude oil recovery device according to claim 1, wherein
evaporation temperature of the extraction solution is 80.degree. C.
or lower under normal pressure.
8. The crude oil recovery device according to claim 1, wherein
evaporation temperature of the extraction solution is 180.degree.
C. or lower under normal pressure.
9. The crude oil recovery device according to claim 3, wherein the
reproduced naphtha tank is provided with a pump or a valve for
taking out the reproduced naphtha from a system.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the foreign priority benefit under
Title 35, United States Code, .sctn.119 (a)-(d) of Japanese Patent
Application No. 2015-190629, filed on Sep. 29, 2015, the disclosure
of which is herein incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a crude oil recovery device
for recovering crude oil from sludge containing crude oil by using
hydrocarbon.
BACKGROUND ART
[0003] For example as the crude oil recovery device, there are
Patent Document 1 and Patent Document 2. Patent Document 1
discloses a method of extracting oil content from a mixture of
solid, water and oil content by using hydrocarbon. Patent Document
2 discloses a method and device configuration for recovering oil
from oil-contaminated soil.
CITATION LIST
Patent Literature
[0004] [Patent Document 1]
[0005] Japanese Patent Application Publication No. H02-273502
[0006] [Patent Document 2]
[0007] Japanese Patent Application Publication No. 2005-081166
SUMMARY OF INVENTION
Technical Problem
[0008] As a method for recovering oil from a mixture of oil, water
and solid, such as extraction of bitumen from tar sand, and
separation of organic matter from refinery sludge, Patent Document
1 discloses a method of using hydrocarbon as an extracting solvent,
obtaining an extraction solution containing oil (solute) extracted
from the mixture by the extracting solvent, separating the
extraction solution into the solute and the extracting solvent by
distilling the extraction solution, and reusing the obtained
extracting solvent for an extraction operation. However, in this
method, since low boiling point hydrocarbons contained in the
solute are also evaporated during reproduction of the extracting
solvent, they are mixed into the reproduced extracting solvent, and
a composition of the extracting solvent constantly changes. When
the composition of the extracting solvent changes, extraction
performance and evaporation characteristics also change, and thus
appropriate extraction operation and evaporation operation are
difficult.
[0009] As a method of recovering oil from the oil-contaminated
soil, Patent document 2 discloses a method of extracting oil
(solute) in the soil by mixing hydrocarbon such as kerosene as the
extracting solvent with the oil-contaminated soil. However, in this
method, since a new solvent is always used as the extracting
solvent, running cost is increased.
[0010] Therefore, an object of the present invention is to provide
a crude oil recovery device for recovering crude oil from an
oil-containing mixture in a stable manner and at low running
cost.
Solution to Problem
[0011] In order to solve the above problems, the present invention
is a crude oil recovery device for extracting crude oil from an
oil-containing mixture composed of water, solid and crude oil,
including an extraction tank for mixing the oil-containing mixture
with an extracting solvent, and an evaporation/liquefaction unit
for distilling an extraction solution after extraction, wherein
naphtha, which is a crude oil component of the oil-containing
mixture, is reused as the extracting solvent, the naphtha being a
distillate obtained by distillation of the extraction solution.
Advantageous Effects of Invention
[0012] According to the present invention, with the crude oil
recovery device for recovering crude oil from the oil-containing
mixture, it is possible to provide the crude oil recovery device
which can be stably operated and can reduce running cost.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is an example of a configuration diagram of a crude
oil recovery device according to an embodiment of the present
invention; and
[0014] FIG. 2 is another example of a configuration diagram of a
crude oil recovery device according to an embodiment of the present
invention.
DESCRIPTION OF EMBODIMENTS
[0015] An example of an embodiment of the present invention will be
described with reference to FIG. 1.
[0016] At first, sludge as an extraction feed and naphtha as an
extracting solvent are introduced into a mixing tank 1 and are
stirred, and thus crude oil in the sludge is dissolved and
extracted by the naphtha. After they are sufficiently stirred and
extraction is completed, a valve 21 is opened so that a mixed
solution is transferred to a liquid-liquid separation tank 2. In
the liquid-liquid separation tank 2, the mixed solution is
separated into an oil phase and an aqueous phase primarily by
gravity. Since a solid contained in the sludge has a high density,
the solid is stored in the aqueous phase side. After the mixed
solution is sufficiently left to stand and separation is completed,
a valve 22 is opened so that the solid is discharged together with
water. After water discharge is completed, the valve 22 is closed
and a valve 23 is opened, so that the naphtha containing crude oil,
which is an extraction solution, is transferred to a recirculation
tank 3.
[0017] When concentration of crude oil in the extraction solution
stored in the recirculation tank 3 is low, the extraction solution
can be reused for extraction as the extracting solvent. Therefore,
when the sludge is introduced into the mixing tank 1, the
extraction solution is transferred to the mixing tank 1 by a pump
32 and is reused as an alternative of the naphtha to be introduced
into the mixing tank 1.
[0018] The above-described operation can be repeated a plurality of
times, however, since the concentration of the crude oil in the
extraction solution is gradually increased and viscosity thereof is
increased, extraction efficiency is reduced. Therefore, when the
number of repetitions exceeds a predetermined number of times, when
the concentration of the crude oil in the extraction solution
exceeds a predetermined concentration of the crude oil, or when the
viscosity thereof exceeds a predetermined viscosity, a valve 24 is
opened so that the extraction solution is transferred to an
extraction solution tank 4.
[0019] Next, flash evaporation is performed to separate the
extraction solution into the extracting solvent and a solute. The
extraction solution stored in the extraction solution tank 4 is
transferred by a pump 31, and temperature of the extraction
solution is increased through a heat exchanger 11 and a heat
exchanger 12 by receiving heat from a distillate and bottom product
to be described below. Further, the extraction solution is heated
to a predetermined temperature by a heater 13, and is transferred
to a gas-liquid separator 5 while low boiling point naphtha is
evaporated. In the gas-liquid separator 5, since heavy component in
the crude oil remaining without evaporation accumulates in a bottom
thereof, the heavy component is discharged as the bottom product
from the bottom thereof by adjusting an open degree of a valve 25
as needed. Further, the heavy component is cooled by the extraction
solution in the heat exchanger 12 and can be recovered as the crude
oil. Meanwhile, vaporized naphtha is discharged from a top of the
gas-liquid separator 5, and is cooled in the heat exchanger 11 and
a cooler 14 to be the distillate, and then is stored in a
reproduced naphtha tank 6.
[0020] When there is not the extraction solution to be used as the
extracting solvent in the mixing tank 1, reproduced naphtha is
transferred to the mixing tank 1 using a pump 33, and is reused as
the extracting solvent.
[0021] As described above, in the present embodiment, almost all of
the naphtha to be used as the extracting solvent circulates in the
device, and further naphtha in the sludge is also incorporated into
a circulation cycle of the extracting solvent by distillation.
Therefore, a total amount of the naphtha in a circulation system
increases, and thus it is possible to properly maintain the total
amount of the naphtha in the circulation system and to recover
surplus naphtha by opening a valve 26 as needed.
[0022] Further, by reducing a control temperature of the heater 13,
it is possible to decrease an amount of circulating naphtha, and to
increase an amount of crude oil to be recovered. Further, when
there is a lot of heavy component in the crude oil in the sludge,
there is a possibility that a portion of the naphtha is discharged
as the bottom product, and the amount of the naphtha in the
circulation cycle of the extracting solvent is decreased, however,
in this case, it is possible to make up for insufficient naphtha by
increasing the control temperature of the heater 13. In general, it
is preferable to distill the extraction solution at 80.degree. C.
or lower, since heat loss is increased as the temperature is
increased. When there is a lot of heavy component in the crude oil
in the sludge, extraction capability is improved if the extracting
solvent contains aromatic compounds, and thus it is preferable to
set the control temperature of the heater 13 to about 180.degree.
C. at which the aromatic compounds are evaporated.
[0023] This device is characterized in that since component
(naphtha) contained in the solute is used as the extracting
solvent, when a maximum temperature in the distillation is set to
be constant, the component of resulting distillate is substantially
constant, and the extraction capability and a specific heat of the
circulating naphtha in the device are substantially constant, and
thus temperature control of distillation and mixing control in the
mixing tank are very easy.
[0024] Further, the liquid-liquid separation tank 2 used here may
be improved in separation performance by using an inclined plate or
the like. Further, it is possible to improve the separation
performance among the oil phase, the aqueous phase and a solid
phase by using a centrifugal separator instead of the liquid-liquid
separation tank 2.
[0025] As described above, the present invention can recover the
crude oil at high efficiency from the sludge containing crude
oil.
[0026] Next, another example of an embodiment of the present
invention will be explained with reference to FIG. 2.
[0027] At first, the sludge as the extraction feed and the naphtha
as the extracting solvent are introduced into the mixing tank 1 and
are mixed, and thus the crude oil in the sludge is dissolved and
extracted by the naphtha. After they are sufficiently stirred and
the extraction is completed, they are left to stand. When they are
sufficiently left to stand, they are separated into the oil phase
and the aqueous phase containing the solid under influence of
gravity. After separation is completed, the valve 22 is opened so
that the solid is discharged together with the water. Here, the
naphtha containing the crude oil remains as the extraction solution
in the mixing tank 1. At this time, when the concentration of the
crude oil in the extraction solution is low, the extraction
solution can be reused as the extracting solvent, and thus it is
possible to repeat the same operation after introducing the sludge
into the mixing tank 1 again. When this operation is repeated, the
concentration of the crude oil in the extraction solution is
gradually increased and a viscosity thereof is increased, and thus
the extraction performance is reduced. Therefore, when the number
of repetitions exceeds a predetermined number of times, when the
concentration of the crude oil in the extraction solution exceeds a
predetermined concentration of the crude oil, or when the viscosity
thereof exceeds a predetermined viscosity, the valve 23 is opened
so that the extraction solution is transferred to the extraction
solution tank 4.
[0028] Next, flash evaporation is performed to separate the
extraction solution into the extracting solvent and the solute. The
extraction solution stored in the extraction solution tank 4 is
transferred by the pump 31 to be heated to a predetermined
temperature by the heater 13, and is transferred to the gas-liquid
separator 5 while the low boiling point naphtha is evaporated. In
the gas-liquid separator 5, the heavy component in the crude oil
remaining without evaporation accumulates in the bottom thereof,
and thus it is possible to recover the crude oil as the bottom
product by adjusting the open degree thereof. Meanwhile, vaporized
naphtha is discharged from the top of the gas-liquid separator 5,
and is cooled by the cooler 14 to be the distillate, and then is
stored in the reproduced naphtha tank 6.
[0029] When the extracting solvent used in the mixing tank 1 is
transferred to the extraction solution tank 4, the reproduced
naphtha is transferred to the mixing tank 1 by the pump 33 and is
reused as the extracting solvent.
[0030] As described above, in the present embodiment, almost all of
the naphtha to be used as the extracting solvent circulates in the
device, and naphtha in the sludge is also incorporated into the
circulation cycle of the extracting solvent by distillation.
Therefore, the total amount of the naphtha in the circulation
system increases, and thus it is possible to properly maintain the
total amount of the naphtha in the circulation system and to
recover the surplus naphtha by opening the valve 26 as needed.
[0031] This device is characterized in that since the component
(naphtha) contained in the solute is used as the extracting
solvent, when the maximum temperature in the distillation is set to
be constant, the component of resulting distillate is substantially
constant, and the extraction capability and the specific heat of
the circulating naphtha in the device are substantially constant,
and thus temperature control of the distillation and mixing control
in the mixing tank are very easy.
[0032] The distillation of the present invention has been described
with an example of flash evaporation, but it may be simple
distillation if it is allowed to sacrifice stability of composition
of a circulating extracting solvent. Further, when the naphtha
cannot be prepared at start-up of the device, it is possible to use
low boiling point hydrocarbons other than the naphtha or a mixture
thereof as the extracting solvent although stability of the device
is reduced.
[0033] Note that, the present invention is not limited to the
embodiments described above, but includes various modifications.
For example, the heat exchanger 11 and the heat exchanger 12 are
provided to improve thermal efficiency of the whole device, but
they can be omitted. Further, the recirculation tank 3 and the
extraction solution tank 4 are separately provided to improve
stability of operation of the device, but they can be integrated
into one.
REFERENCE SIGNS LIST
[0034] 1: mixing tank [0035] 2: liquid-liquid separation tank
[0036] 3: recirculation tank [0037] 4: extraction solution tank
[0038] 5: gas-liquid separator [0039] 6: reproduced naphtha tank
[0040] 11: heat exchanger [0041] 12: heat exchanger [0042] 13:
heater [0043] 14: cooler
* * * * *