U.S. patent application number 12/234987 was filed with the patent office on 2009-07-09 for high power microwave petroleum recovery.
This patent application is currently assigned to Colorado Seminary. Invention is credited to Ravi Varma.
Application Number | 20090173488 12/234987 |
Document ID | / |
Family ID | 40824621 |
Filed Date | 2009-07-09 |
United States Patent
Application |
20090173488 |
Kind Code |
A1 |
Varma; Ravi |
July 9, 2009 |
HIGH POWER MICROWAVE PETROLEUM RECOVERY
Abstract
Methods, systems, and devices are described for using high-power
microwave radiation to recover oil from an oil shale deposit.
Embodiments include a microwave generation system, adapted to
generate in situ, high-power microwave radiation. In some
embodiments, one or more antennae propagate the microwave radiation
into the oil shale deposit. The microwave radiation may heat the
oil shale, causing oil to be released. The released oil may then be
collected, refined, transported, or otherwise processed.
Inventors: |
Varma; Ravi; (Louisville,
CO) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP
TWO EMBARCADERO CENTER, EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
Colorado Seminary
Denver
CO
|
Family ID: |
40824621 |
Appl. No.: |
12/234987 |
Filed: |
September 22, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61018818 |
Jan 3, 2008 |
|
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|
Current U.S.
Class: |
166/60 ;
166/302 |
Current CPC
Class: |
E21B 43/2401
20130101 |
Class at
Publication: |
166/60 ;
166/302 |
International
Class: |
E21B 43/24 20060101
E21B043/24 |
Claims
1. A system for recovering oil from an oil shale deposit, the
system comprising: a microwave generation system, adapted to
generate microwave radiation substantially at a microwave frequency
and substantially at a power level; and a radiation system,
operatively coupled with the microwave generation system, and
comprising: an antenna, adapted to transmit at least a portion of
the microwave radiation at the microwave frequency into the oil
shale deposit, wherein the antenna is located within the oil shale
deposit and the at least a portion of the microwave radiation is
transmitted substantially omni-directionally; and a sheath, adapted
to be substantially transparent to the microwave frequency in at
least one transmission direction, and adapted to mitigate harmful
physical exposure of the antenna to the oil shale deposit and
released constituents, wherein the released constituents comprise
constituents of the oil shale deposit released during heating as a
result of the antenna transmitting at least a portion of the
microwave radiation at the microwave frequency into the oil shale
deposit, one of the released constituents being released oil.
2. The system of claim 1, wherein the microwave generation system
comprises: a klystron, adapted to generate microwave radiation at
the microwave frequency, the microwave frequency being
substantially 2.45 to 2.5 GHz.
3. The system of claim 1, wherein the microwave generation system
comprises: a klystron, adapted to generate microwave radiation at
the power level, the power level being selected from a group
consisting of: substantially one-half megawatt; substantially 100
kilowatt; and substantially 4.5 megawatt.
4. The system of claim 1, wherein the microwave generation system
comprises: a klystron, adapted to generate microwave radiation at
the microwave frequency as pulsed-wave radiation.
5. The system of claim 1, wherein at least a portion of the
microwave generation system is located within the oil shale
deposit.
6. The system of claim 1, wherein the radiation system further
comprises: a wave guide, operatively coupled with the microwave
generation system and the antenna, and adapted to guide the
propagation of substantially all of the microwave radiation at the
microwave frequency from the microwave generation system to the
antenna.
7. The system of claim 1, wherein the antenna comprises: a
rectangular cross-section having two wide faces and two narrow
faces; and a plurality of slots penetrating each of the wide faces
and adapted to transmit at least a portion of the microwave
radiation at the microwave frequency.
8. The system of claim 1, wherein the radiation system further
comprises: a plurality of antennae distributed throughout the oil
shale deposit, each of the plurality of antennae being operatively
coupled with the microwave generation system, wherein the antenna
is one of the plurality of antennae.
9. The system of claim 1, wherein: the microwave generation system
comprises a plurality of microwave generators; and the radiation
system further comprises: a plurality of antennae distributed
throughout the oil shale deposit, each of the plurality of antennae
being operatively coupled with at least one of the microwave
generators.
10. The system of claim 1, wherein the radiation system further
comprises: a reflector unit, located substantially within the oil
shale deposit and adapted to receive incident microwave radiation
in a first direction and transmit at least a portion of the
incident microwave radiation in a second direction, the second
direction being different from the first direction and oriented
towards a portion of the oil shale deposit, wherein the incident
microwave radiation comprises a portion of the microwave radiation
transmitted by the antenna into the oil shale deposit.
11. The system of claim 1, wherein the radiation system further
comprises: a first reflector unit, located substantially within the
oil shale deposit at a first distance from the antenna, and adapted
to: be substantially transparent to microwave radiation received in
a first direction; and be substantially reflective to microwave
radiation received in a second direction; and a second reflector
unit, located substantially within the oil shale deposit at a
second distance from the antenna, the second distance being greater
than the first distance, wherein the second reflector unit is
adapted to: be substantially reflective to microwave radiation
received in the first direction.
12. The system of claim 1, further comprising: a power management
system, operatively coupled with the microwave generation system,
and adapted to manage power supplied to the microwave generation
system.
13. The system of claim 1, further comprising: an oil extraction
system, adapted to transport the released constituents from the oil
shale deposit to a collection location.
14. The system of claim 13, further comprising: an oil collection
system, adapted to collect the released oil at the collection
location.
15. The system of claim 14, wherein the oil collection system
comprises a surface oil collector.
16. The system of claim 13, wherein the oil extraction system
further comprises: piping located in a bore hole bored into the oil
shale deposit and adapted to direct the flow of at least a portion
of the released constituents toward the collection location.
17. The system of claim 16, wherein the piping is substantially
sealed and comprises a region adapted to allow entry of at least a
portion of the released constituents into the pipe through the
region.
18. The system of claim 16, wherein the piping comprises a lower
end located substantially at the depth of oil shale deposit, the
lower end comprising a seal, wherein the sheath is operatively
coupled with the seal at the lower end of the piping and located
within the bore hole.
19. The system of claim 13, further comprising: an oil processing
system, adapted to process at least a portion of the released
constituents.
20. The system of claim 15, wherein the oil processing system is
further adapted to extract the released oil from the released
constituents and to at least partially refine the released oil.
21. The system of claim 15, further comprising: a power management
system, operatively coupled with the microwave generation system,
and adapted to manage power supplied to the microwave generation
system, wherein the oil processing system comprises a recycling
system, adapted to recycle at least a portion of the released
constituents for use by the power management system.
22. The system of claim 1, further comprising: a sensor system,
adapted to generate feedback information as a function of at least
one environmental condition.
23. The system of claim 22, wherein the at least one environmental
condition relates to at least one of: an amount of the released
constituents; a composition of the released constituents; a
temperature; or a pressure.
24. The system of claim 22, wherein the sensor system comprises a
plurality of dielectric probes, at least a portion of the
dielectric probes being located within the oil shale deposit.
25. The system of claim 22, wherein the sensor system comprises a
millimeter-wave spectrometer, adapted to determine a composition of
at least a portion of the released constituents.
26. The system of claim 22, further comprising: a feedback control
system, adapted to: receive feedback information from the sensor
system; and make a reconfiguration determination as a function of
the feedback information, wherein the reconfiguration determination
relates to at least one of: the microwave frequency; the power
level; a polarity of the microwave radiation; a direction of
propagation of the microwave radiation; a depth of transmission of
the microwave radiation; or a location of transmission of the
microwave radiation.
27. A method for recovering oil from an oil shale deposit, the
method comprising: generating microwave radiation substantially at
a microwave frequency; and transmitting at least a portion of the
microwave radiation substantially omni-directionally into the oil
shale deposit from an active radiation source located substantially
within the oil shale deposit, such that at least a portion of the
oil shale deposit heats to a temperature level at which released
constituents are released, the released constituents comprising
released oil.
28. The method of claim 27, further comprising: receiving incident
microwave radiation in a first direction from a radiation source;
and transmitting at least a portion of the incident microwave
radiation in a second direction, the second direction being
different from the first direction and oriented towards a portion
of the oil shale deposit.
29. The method of claim 28, wherein the incident microwave
radiation comprises at least a first portion of the microwave
radiation transmitted by the active radiation source, at least a
second portion of the microwave radiation transmitted by the active
radiation source having been absorbed by a portion of the oil shale
deposit.
30. The method of claim 27, further comprising: transporting at
least a portion of the released constituents from the oil shale
deposit to a collection location.
31. The method of claim 27, further comprising: processing at least
a portion of the released constituents.
32. The method of claim 27, further comprising: sensing feedback
information as a function of at least one environmental condition;
and making a reconfiguration determination as a function of the
feedback information, wherein the reconfiguration determination
relates to at least one of: the microwave frequency; the power
level; a polarity of the microwave radiation; a direction of
propagation of the microwave radiation; a depth of transmission of
the microwave radiation; or a location of transmission of the
microwave radiation.
33. A method for recovering oil from an oil reservoir site, the
method comprising: providing an oil collection system; pumping a
measured amount of water into the oil reservoir site, wherein the
oil reservoir site is underground and comprises oil; generating
microwave radiation substantially at a microwave frequency; and
transmitting at least a portion of the microwave radiation into the
oil reservoir site from a plurality of active radiation sources
located substantially within the oil reservoir site, such that at
least a portion of the water heats to a temperature level at which
sufficient steam is generated to force the oil into the oil
collection system.
34. The method of claim 33, wherein at least a portion of the
plurality of active radiation sources comprises a klystron and an
antenna.
Description
CROSS REFERENCES
[0001] This application claims priority from co-pending U.S.
Provisional Patent Application No. 60/018,818, filed Jan. 3, 2008,
entitled "HIGH POWER MICROWAVE PETROLEUM RECOVERY" (Attorney Docket
No. 026882-000300US), which is hereby incorporated by reference, as
if set forth in full in this document, for all purposes. This
application is also related to co-pending U.S. Non-Provisional
patent application Ser. No. ______, filed concurrently herewith,
entitled "HIGH POWER MICROWAVE PETROLEUM REFINEMENT" (Attorney
Docket No. 026882-000320US), which is hereby incorporated by
reference, as if set forth in full in this document, for all
purposes.
[0002] The present invention relates to petroleum recovery in
general and, in particular, to recovery of petroleum from oil shale
underground through in situ heating.
BACKGROUND
[0003] Oil shale may typically occur in sedimentary rocks
containing solid bituminous material. Some rich deposits may be
found underground in the western United States, as kerogen mixed
with minerals (e.g., halites, nahacolites, dawsonites, etc.). In
some cases, geologically trapped water, combined with water of
crystallization in the minerals, may constitute up to 3 percent by
weight of the deposits.
[0004] The composition of the oil shale may be such that petroleum
oil can be released on heating. The heating process may involve
heating kerogen trapped within the oil shale until it becomes hot
enough to convert (e.g., pyrolyse, decompose, etc.) into shale oil,
shale gas, solid residue, and/or other constituents. While the
kerogen may be a relatively useless hydrocarbon, the conversion to
shale oil will create a hydrocarbon that may be useful as a
non-conventional fuel oil. In some cases, the conversion may begin
at around 300.degree. C., but may become faster and more complete
as the temperature increases (e.g., to 450.degree. C.). Further,
some gasification may occur as temperatures continue to rise (e.g.,
to 575.degree. C.).
[0005] There are at least two categories of heating processes
relating to where the heating should occur: ex situ and in situ.
With ex situ heating, or ground-surface retorting, oil shale may be
mined at or below the surface and transported to a retorting
facility. In situ heating processes, however, may convert the
kerogen through a bore hole while the oil shale is still in the
ground, extracting crude oil straight from the oil shale deposit.
Some in situ retorting processes, called modified in situ processes
("MIS"), may involve creating a fractured area above the mined area
to aid in vapor/gas flow through the deposit.
[0006] In situ heating processes may differ in a number of ways.
For example, such processes may heat the oil shale deposit using a
variety of technologies, including conductive heating, steam,
combustion, microwaves, radiofrequency, and others. Further, some
processes may heat from the surface, while others may lower heating
elements to depths within the deposit. While many of these
processes may be effective for extracting crude oil, they may not
provide cost effective solutions (e.g., they use a lot of energy
per amont extracted) and may be environmentally undesirable (e.g.,
by causing groundwater pollution or producing toxic
by-products).
[0007] As such, it may be desirable to provide efficient and
effective in situ heating of oil shale deposits.
SUMMARY
[0008] Among other things, embodiments of the invention provide
systems, devices, and methods for using high-power microwave
radiation to recover oil from an oil shale deposit. One embodiment
includes a microwave generation system, adapted to generate
high-power microwave radiation. A radiation system may be coupled
with the microwave generation system. The radiation system may
include an antenna for transmitting the radiation into the oil
shale deposit, the antenna being located in situ (i.e., within the
oil shale deposit). A sheath may be provided to protect the antenna
from harmful exposure to the oil shale deposit and released
constituents, while being substantially transparent to the
microwave frequency. The high-power microwave radiation may heat
the oil shale, causing oil to be released. The released oil may
then be collected, refined, transported, or otherwise
processed.
[0009] One set of embodiments provides a method for recovering oil
from an oil shale deposit using in situ, high-power, microwave
heating. The method includes generating microwave radiation
substantially at a microwave frequency (e.g., approximately 2.45 to
2.5 GHz); and transmitting at least a portion of the microwave
radiation into the oil shale deposit from an active radiation
source located substantially within the oil shale deposit, such
that at least a portion of the oil shale deposit heats to a
temperature level at which released constituents are released, the
released constituents comprising oil.
[0010] Another set of embodiments provides a method for recovering
oil from an oil reservoir site. The method includes providing an
oil collection system; pumping a measured amount of water into the
oil reservoir site, wherein the oil reservoir site is underground
and comprises oil; generating microwave radiation substantially at
a microwave frequency; and transmitting at least a portion of the
microwave radiation into the oil reservoir site from a plurality of
in situ radiation sources (e.g., in proximity to the oil reservoir
site), such that at least a portion of the water heats to a
temperature level at which sufficient steam is generated (e.g., at
high pressure) to force the oil into the oil collection system. In
certain embodiments, at least a portion of the radiation sources
includes a klystron and an antenna. In certain of these
embodiments, the antenna is protected by an enclosure that is
substantially transparent to the microwave radiation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A further understanding of the nature and advantages of the
present invention may be realized by reference to the following
drawings. In the appended figures, similar components or features
may have the same reference label. Further, various components of
the same type may be distinguished by following the reference label
by a dash and a second label that distinguishes among the similar
components. If only the first reference label is used in the
specification, the description is applicable to any one of the
similar components having the same first reference label
irrespective of the second reference label.
[0012] FIG. 1 shows a simplified system block diagram of an oil
recovery system, according to various embodiments of the
invention.
[0013] FIG. 2 shows a simplified illustration of an oil recovery
system, according to various embodiments of the invention.
[0014] FIGS. 3A and 3B show illustrations of a front view and a
side view of an antenna, respectively, according to various
embodiments of the invention.
[0015] FIG. 4 shows an illustration of a top view of an oil shale
deposit with multiple distributed antennae, according to various
embodiments of the invention.
[0016] FIG. 5A shows an illustration of a top view of an oil shale
deposit with a single antenna and a single reflector, according to
various embodiments of the invention.
[0017] FIG. 5B shows an illustration of a top view of an oil shale
deposit with a single antenna, an outer reflector, and an inner
reflector, according to various embodiments of the invention.
[0018] FIG. 5C shows an illustration of a top view of an oil shale
deposit with multiple antennae, an outer reflector, and an inner
reflector, according to various embodiments of the invention.
[0019] FIG. 6 provides a flow diagram of a method for oil recovery,
according to various embodiments of the invention.
[0020] FIG. 7 provides a flow diagram of a method for oil recovery
from an existing reservoir site, according to various embodiments
of the invention.
[0021] FIG. 8 shows a simplified illustration of an oil recovery
system, modified for preprocessing of the recovered oil, according
to various embodiments of the invention.
[0022] FIG. 9 shows a simplified illustration of a partial oil
recovery system, modified with a generator 920 for preprocessing of
the recovered oil, according to various embodiments of the
invention.
[0023] FIG. 10 shows a simplified illustration of a partial oil
recovery system, modified with a generator 920 and a perforated
separator 1006 for preprocessing of the recovered oil, according to
various embodiments of the invention.
[0024] FIG. 11 provides a flow diagram of a method for processing
oil emulsions to separate oil and non-oil constituents of the
emulsion, according to various embodiments of the invention.
[0025] FIG. 12 provides a flow diagram of a method for processing
heavy oil into lighter oil, according to various embodiments of the
invention.
DETAILED DESCRIPTION
[0026] This description provides example embodiments only, and is
not intended to limit the scope, applicability, or configuration of
the invention. Rather, the ensuing description of the embodiments
will provide those skilled in the art with an enabling description
for implementing embodiments of the invention. Various changes may
be made in the function and arrangement of elements without
departing from the spirit and scope of the invention.
[0027] Thus, various embodiments may omit, substitute, or add
various procedures or components, as appropriate. For instance, it
should be appreciated that in alternative embodiments, the methods
may be performed in an order different from that described, and
that various steps may be added, omitted, or combined. Also,
features described with respect to certain embodiments may be
combined in various other embodiments. Different aspects and
elements of the embodiments may be combined in a similar
manner.
[0028] It should also be appreciated that the following systems,
methods, and apparatuses may individually or collectively be
components of a larger system, wherein other procedures may take
precedence over or otherwise modify their application. Also, a
number of steps may be required before, after, or concurrently with
the following embodiments.
[0029] Embodiments of Oil Recovery Systems and Methods
[0030] Among other things, embodiments of the invention provide
systems, devices, and methods for using high-power microwave
radiation to heat oil shale deposits. Some embodiments use
high-power klystrons to generate either continuous or pulsed
microwave radiation. The microwaves may be applied to the oil shale
deposits in situ, substantially at the depth of the oil shale
deposit. In some geographic locations, oil shale deposits may be
seen at relatively shallow depths (e.g., tens or hundreds of feet
below the ground surface), while in other geographic locations, oil
shale deposits may be significantly deeper (e.g., around 1000 feet
below the ground surface).
[0031] Heating the oil shale may cause oil to be released (e.g.,
from kerogen). The oil released from the oil shale deposit may then
be forced out to the ground surface by pressure from superheated
steam generated from the heating of the oil shale and mineral
deposits. For example, the heating of the oil shale deposit may
generate approximately sixty to three hundred atmospheres of
pressure. In some cases, this may provide sufficient pressure to
force the released oil from the oil shale deposit to the ground
surface without a need for additional sources of pressure (e.g.,
additional pumping of gases into the deposit).
[0032] In some embodiments, an oil recovery system is provided to
help direct the released oil into a collector when it is forced to
the ground surface. For example, the oil recovery system may
include one or more pipes and other components sunk into a bore
hole approximately to the depth of the oil shale deposit. The
released oil may be forced into and up the bore hole via pipes
and/or other components of the oil recovery system, and directed
into a surface collector.
[0033] FIG. 1 shows a simplified system block diagram of an oil
recovery system, according to various embodiments of the invention.
The oil recovery system 100 includes a number of subsystems for
heating an oil shale deposit to release oil and recovering the
released oil in a useful way. In some embodiments, a power
management system 104 provides power to a microwave generation
system 108, which generates a certain type of high-power microwave
radiation (e.g., pulse or continuous-wave). The radiation may be
transmitted into an oil shale deposit 116 via an in-situ radiation
system 112 (e.g., one or more antennae) for heating the oil shale
deposit 116. As the oil shale deposit 116 heats, physical and/or
chemical processes generate a set of released constituents 120
(e.g., oil, gases, etc.). The released constituents 120 may be
handled by an oil extraction system 124 adapted at least to direct
the released oil to an oil collection system 128. Oil collected in
the oil collection system 128 may then be refined, transported,
and/or otherwise processed by an oil processing system 132.
[0034] Embodiments of the oil recovery system 100 include a power
management system 104 adapted to provide and manage power to the
oil recovery system 100. Any useful power management system 104 may
be used, including power generators, converters, etc. In some
embodiments, the power management system 104 includes components to
generate power on-site (e.g., near the oil shale deposit); while in
other embodiments, the power management system 104 includes
components to generate power off-site and transport the power
on-site. In one embodiment, the power management system 104
includes components to couple with existing or supplemental utility
provisions (e.g., the electrical grid, on-site wind turbines, etc.)
and convert the power for use by the oil recovery system 100. In
another embodiment, the power management system 104 includes
components for recycling products of the oil recovery system 100
for use in generating power. For example, hot gases (e.g., fuel
bearing gases) generated by the oil recovery system 100 may be
recovered to generate electricity for the oil recovery system
100.
[0035] In some embodiments, the power management system 104 manages
power provided for operation of a microwave generation system 108.
The microwave generation system 108 may generate microwave
radiation with certain characteristics (e.g., power, frequency,
waveform, etc.), which may be transmitted to an oil shale deposit
116 via an in situ radiation system 112. In various embodiments,
the microwave generation system 108 may include one or more
klystrons, magnetrons, and/or other microwave generation
components.
[0036] In certain embodiments, the microwave generation system 108
generates high-power microwave radiation. In one embodiment, a
1.5-4.5 megawatt, high-power klystron is used to generate
approximately 2.856 GHz pulsed-wave microwave radiation at an
efficiency of approximately forty-two percent (e.g., or 32 to 44
percent). In another embodiment, a one-hundred kilowatt (i.e.,
average power), high-power klystron is used to generate
approximately 2.45 GHz continuous-wave microwave radiation at an
efficiency of approximately sixty percent. It will be appreciated
that high-power klystrons may be more efficient than low-power
klystrons and may provide better penetration of the microwave
radiation into the oil shale deposit. Further, continuous wave
radiation may be generated more efficiently than pulse-wave
radiation. However, pulse-wave radiation may provide higher peak
electric field intensities for a given amount of energy expended,
as compared to continuous-wave radiation.
[0037] In some embodiments, the release of oil from the oil shale
deposit 116 may be related to the intensity of the microwave
electrical field used to heat the oil shale. Because pulsed waves
may tend to generate higher electrical field intensities than
comparable continuous waves, it may be desirable in certain
embodiments to use pulse-wave radiation. For a certain klystron,
using pulse-wave radiation may substantially reduce its efficiency
(e.g., from approximately sixty percent to approximately forty-four
percent) and reduce the average power of the output (e.g., from
approximately one hundred kilowatts to approximately twenty-two
kilowatts for twenty-microsecond pulses). The advantages gained by
an increase in field intensity, however, may offset or outweigh any
disadvantages due to a decrease in output power or efficiency, as a
net gain in output efficiency may result. For example, higher power
radiation may generate a higher intensity electric field, which may
in turn increase the rate of reaction (e.g., or reaction kinetics).
As such, use of pulse power may cause more oil to be recovered per
unit time (e.g., as compared with continuous-wave power), such that
the microwave generation system 108 may run for a shorter total
duration.
[0038] As such, some embodiments of the microwave generation system
108 are adapted to generate pulse-wave radiation, while other
embodiments of the microwave generation system 108 are adapted to
generate continuous-wave radiation. It will be appreciated that
other characteristics of the radiation may also affect its
usefulness for various purposes, including oil extraction
efficiency, power consumption efficiency, compatibility with
available components, compatibility with certain materials, etc.
For example, embodiments of the microwave generation system 108 may
be adapted to generate radiation of different polarities,
waveforms, frequencies, amplitudes, etc.
[0039] Embodiments of the microwave generation system 108 include
an in-situ radiation system 112 for transmitting the radiation
generated by the microwave generation system 108 into the oil shale
deposit 116. In some embodiments, the in-situ radiation system 112
includes one or more antennae. In certain embodiments, the antenna
or antennae are situated in a bore hole sunk into the oil shale
deposit 116 (e.g., see FIG. 3). In other embodiments, some or all
of the antenna or antennae are situated outside the bore hole
within the oil shale deposit 116. For example, a set of antennae
may be distributed throughout the oil shale deposit 116 to allow
for more efficient irradiating of certain parts of the oil shale
deposit 116 (e.g., see FIG. 5A).
[0040] In various embodiments, the antenna or antennae may be in
various proximities to one or more components of the microwave
generation system 108. In one embodiment, the microwave generation
system 108 includes a single generator (e.g., a single klystron),
coupled with a single antenna using a wave guide. The wave guide is
adapted to efficiently transmit the radiation from the klystron to
the antenna for transmission to the oil shale deposit 116 (e.g.,
with substantially no loss). In another embodiment, the microwave
generation system 108 includes a single generator coupled with
multiple antennae using multiple wave guides. In yet another
embodiment, the microwave generation system 108 includes multiple
generators, each coupled with one or more antennae via one or more
wave guides. It will be appreciated that, where there are multiple
generators, antennae, and/or wave guides, each may be the same or
different as the others, depending on known antenna design factors
and characteristics of the oil shale deposit 116 and the components
of the oil recovery system 100.
[0041] It will be appreciated that many types of antennae and wave
guides are possible, according to embodiments of the invention. For
example, the components of the in-situ radiation system 112 may be
adapted to optimize transmission of a particular frequency,
polarity, etc. In some embodiments, the shape, size, configuration,
and/or other characteristics of the in-situ radiation system 112
are designed to affect the radiation in a particular way. For
example, the shape may be selected to shape the radiation waveforms
(e.g., a rectangular waveguide for rectangular waves (TE/TM
modes)), the material may be selected for transmitting certain
frequencies (e.g., copper, etc.), the antenna may be sized,
slotted, and/or capped to increase transmission of certain
frequencies, etc.
[0042] Embodiments of the in-situ radiation system 112 may include
other components for added functionality. For example, it may be
desirable to shield the antenna from certain environmental
externalities, such as hot oil and gases being released from the
oil shale deposit 116. As such, some embodiments include a sheath
or other type of shield for surrounding an antenna. In certain
embodiments, the sheath is designed to allow propagation of
radiation, while shielding the antenna from the environmental
externalities. For example, in one embodiment, the sheath has a
ten-inch inner diameter and a wall thickness of 0.25 inches, and is
manufactured from a composition of fused silica that is
approximately one hundred percent transparent to the propagation of
2.45 GHz microwave radiation. In another embodiment, the sheath is
manufactured from polytetrafluoroethylene ("PTFE"), high-density
polyethylene (e.g., ECCO STOCK CPE from Emerson and Cummings), or
fused silica (e.g., for added durability). In other embodiments,
other components, like repeaters, optics, etc., are provided to aid
in the transmission of desired radiation into the oil shale deposit
116. For example, certain radiation reflectors may be situated in
the oil shale deposit 116 to reflect and/or focus unabsorbed
radiation back into the oil shale deposit 116 or into a certain
portion of the oil shale deposit 116.
[0043] Oil shale may typically manifest as a layered, deposited bed
of kerogen (a bituminous solid) in a porous rock matrix. The rock
matrix may contain associated free water and bound water, some of
the water being water of crystallization in minerals, including
carbonates, silicates, and phosphates mixed with pyrite. The
intertwined matrices may contain geologically trapped water of
around 1.5 to 3 percent by weight in the oil shale deposit 116, in
addition to the water of crystallization in mineral
constituents.
[0044] When high-power microwave radiation is propagated into the
oil shale deposit 116, the radiation may be absorbed, though
typically weakly, by the oil shale (which may have a low dielectric
loss of around 0.4). Super-heated steam may be generated by
vaporizing the geologically trapped water. The steam pressure may
cause oil shale layers to fracture as the radiation penetrates into
the oil shale deposit 116. Oil may begin to be released from the
oil shale when the localized temperature reaches a particular level
(e.g., around 450.degree. C. at approximately fifty atmospheres or
more). As the temperature continues to rise, more oil may be
released. Additionally, at higher temperatures (e.g., 525.degree.
C.), there may be further cracking and some gasification of
residual oil (e.g., promoted by catalysis from the minerals
present).
[0045] As such, irradiating, and thereby heating, the oil shale
deposit 116 may cause constituents 120 of the oil shale deposit 116
to be released. These released constituents 120 may include oil, as
well as solid particulates, gases (e.g., steam, CO.sub.2, etc.),
and other constituents. In some cases, the released constituents
120 are simply released from the oil shale deposit 116 (e.g.,
trapped kerogen may be released). In other cases, the released
constituents 120 include chemically generated and/or altered
constituents (e.g., trapped water may be released as steam and some
residual oil may be gasified).
[0046] Embodiments of the oil recovery system 100 include an oil
extraction system 124 for handling the released constituents 120.
In some embodiments, the oil extraction system 124 includes
components for directing the flow of at least a portion of the
released constituents 120. For example, the oil extraction system
124 may include pipes, conduits, drains, sieves, valves, pumps,
etc. In certain embodiments, an area around the bore hole is
treated to create high ground surface pressure. For example,
compressed concrete and soil may be provided in the vicinity of the
bore hole. In this way, pressure built up from the release of the
released constituents 120 (e.g., pressure from superheated steam
and other gases) may cause the released oil to find lower pressure
exit paths, which may force at least a portion (e.g., substantially
all) of the released oil into and up the bore hole (e.g., through
one or more pipes). Certain seals, valves, and/or openings may be
provided to control various pressures, to better direct the flow of
oil.
[0047] In some embodiments, the oil extraction system 124 is
adapted to direct the oil into an oil collection system 128. For
example, the oil collection system 128 may include a surface oil
collector for collecting any oil leaving the bore hole. Those of
skill in the art will appreciate that many oil collection systems
and techniques may be used in accordance with embodiments. For
example, the oil collection system 128 may include components for
storage, absorption, separation, skimming, etc.
[0048] For example, as gases are generated and/or released by the
heating of the oil shale deposit 116, pressure in the region of the
oil shale deposit 116 may increase. Appropriate management of this
pressure may cause fracture of the oil shale deposit 116, which may
cause the released constituents of the oil shale deposit 116,
including released oil, to be forced (e.g., upwards) to lower
pressure areas. By providing a low pressure environment within the
bore hole (e.g., using piping), oil and other released constituents
may be forced up the bore hole and into a surface collector.
[0049] Once the oil has been collected (e.g., or while the oil is
being collected) by the oil collection system 128, embodiments may
process the oil using an oil processing system 132. Some
embodiments of the oil processing system 132 include components for
refining the collected oil. It will be appreciated that the
collected oil may be an oil emulsion. For example, the oil may
contain various contaminants and/or impurities, the oil may be
heavy (e.g., containing highly viscous macromolecules of
hydrocarbons), etc. In these and other cases, the oil processing
system 132 may be used to partially or completely refine the oil
(e.g., into light crude oil, or some other form of useful oil).
Other embodiments of the oil processing system 132 may include
components for transporting the oil (e.g., pipelines, barges,
tankers, drums, pumps, reservoirs, etc.).
[0050] FIG. 2 shows a simplified illustration of an oil recovery
system, according to various embodiments of the invention. The oil
recovery system 200 is situated in substantial proximity to a bore
hole 202 which has been drilled into an oil shale deposit 206. The
bore hole 202 may be drilled in any useful way, and may follow any
useful path. In some embodiments, the bore hole 202 is drilled
vertically, following a substantially straight path into the oil
shale deposit. In other embodiments, the bore hole 202 is drilled
horizontally or at an angle and/or following a non-linear path. It
will be appreciated that the various components of embodiments of
the invention may be oriented and/or situated to account for the
direction of the bore hole 202 path (e.g., so as to ultimately
direct released oil into a vertical section of the oil recovery
system 200). In one embodiment, the bore hole 202 is approximately
one thousand feet deep and approximately sixteen inches in
diameter.
[0051] In some embodiments, at the surface of the bore hole 202 and
extending outward for some distance, there may be layers of
compacted soil and concrete 204. These layers of compacted soil and
concrete 204 may help mitigate seepage of liquids and gases (e.g.,
oil, steam, etc.) through the ground surface in proximity to the
bore hole 202. It will be appreciated that the layers of compacted
soil and concrete 204 may be supplemented or supplanted by other
materials to help minimize seepage through the surrounding ground
surface. It will be further appreciated that, as discussed above,
the layers of compacted soil and concrete 204 may cause underground
pressure to develop to help direct the flow of released oil into
oil extraction and collection components.
[0052] In some embodiments, a power supply 210 is provided. The
power supply 210 may be part of a power management system, like the
power management system 104 of FIG. 1. In some embodiments, all or
part of the power supply 210 is situated outside the bore hole 202
on or near the ground surface (e.g., on the layers of compacted
soil and concrete 204). In some embodiments, some or all of the
power supply 210 is situated in close proximity to the bore hole
202 to minimize the distance between the power supply 210 and
components requiring power (e.g., the generator 220).
[0053] Embodiments of the power supply 210 may include any system
or group of systems capable of generating or supplying adequate
power for the oil recovery system 200. In certain embodiments, the
power supply 210 may include components (e.g., a transformer)
capable of interfacing with an existing power grid. In other
embodiments, the power supply 210 may include power generating
components, like wind turbines, battery-coupled solar cells,
nuclear reactors, hydroelectric generators, or any other useful
power generator. The power supply 210 may also include back-up
systems, fail safes, rectifiers, and other components to help
maintain substantially constant power with certain characteristics
(e.g., certain voltage, frequency, and lack of interference).
[0054] In some embodiments, the power supply 210 outputs power
through one or more power cables 212. As such, one end of the power
cable 212 may be coupled with the power supply 210. In some
embodiments, all or a portion of the power cable 212 may be
shielded (e.g., by additional tubing, conduit, or other shielding)
to protect the cable from externalities that may damage the power
cable 212 or affect the transmission of power or other signals
through the power cable 212. By way of example, these externalities
may include heat, moisture, or electromagnetic fields. In certain
embodiments, the power cable(s) 212 may be manufactured or adapted
to provide added functionality. For example, the power cable 212
may be split into multiple cables that can be coupled using
integrated connectors. This may allow parts of the oil recovery
system 200 to be more easily installed in pieces (e.g.,
subassemblies). In other examples, added functionality may be
provided by supplying redundant power cables; including data cables
or data transmission capabilities; insulating and/or shielding
cables for handling electromagnetic interference, chaffing,
exposure to environmental externalities, etc.; or in many other
ways.
[0055] In some embodiments, the power cable 212 may be coupled with
a generator 220, allowing the provision of power from the power
supply 210 to the generator 220. Embodiments of the generator 220
may be included in a microwave generation system like the microwave
generation system 108 of FIG. 1. In some embodiments, the generator
220 may be sunk into the bore hole 202 and situated in proximity to
the depth where oil will be extracted from the oil shale deposit
206. In other embodiments, the generator 220 may be located at or
near the ground surface. However, it will be appreciated that
situating the generator 220 in proximity to the oil shale deposit
206 may increase the efficiency of the production of oil from the
oil shale deposit 206.
[0056] Embodiments of the generator 220 are adapted to generate
high-power microwave radiation. In some embodiments, a high-power
klystron is used for generating approximately 2.45 GHz radiation at
approximately one-half megawatt (e.g., or 100 kilowatts) of power.
Certain embodiments of the generator 220 provide continuous-wave
radiation, while other embodiments provide pulse-wave radiation.
The generator 220 may be adapted to operate only at around one
frequency or it may be adjustable (e.g., tunable). Further, the
generator 220 may be adapted to generate particular polarizations,
shapes, amplitudes, and other characteristics of radiation.
[0057] It will be appreciated that different types of radiation may
be desirable depending on certain characteristics of the oil shale
deposit 206. For example, high-power, 2.45-2.5 GHz radiation (e.g.,
at approximately 4.5 megawatt of power) may be desirable for oil
shale deposits 206 of a certain type found at around one thousand
feet below ground level. However, for shallower oil shale deposits
206 (e.g., tar sands, shallow pits, etc.), lower powers or
different frequencies may be more desirable.
[0058] In some embodiments, the microwave radiation is propagated
into the oil shale deposit 206 from the generator 220 via an
antenna 224. The antenna 224 may be adapted to optimize the amount
and direction of microwave radiation into the oil shale deposit
206. In some embodiments, the antenna 224 may be capped at the
bottom to increase its effectiveness. It will be appreciated that
many types and configurations of antenna 224 are possible,
according to embodiments of the invention. An illustrative
embodiment of the antenna 224 can be seen in FIG. 3.
[0059] FIGS. 3A and 3B show illustrations of a front view and a
side view of an antenna, respectively, according to embodiments of
the invention. For clarity, FIGS. 3A and 3B will be discussed in
parallel. It will be appreciated that the illustrated antenna 300
is only one of many possible antennae, and should not be construed
as limiting the invention in any way. For example, the specifics of
the antenna 300 design may be adjusted for transmission of
different frequencies, wave shapes, polarizations, directionality,
etc.
[0060] In some embodiments, the antenna 300 may have a housing 330
with a length 302 of approximately one meter and a rectangular
cross-section. The housing 330 may be manufactured separately or as
part of a wave guide. In one embodiment, the antenna 300 is a
linear portion of a WR 340 copper wave guide. The antenna 300 may
be designed to transmit microwave radiation at 2.45 GHz.
[0061] In some embodiments, the housing 330 has two wide faces 306
opposite each other, each having an inner width 304-1 of
approximately 3.40 inches, and two narrow faces 308, each having an
inner width 304-2 of approximately 1.70 inches. The housing 330 may
also be shorted at the bottom by an adjustable plug 332, and may be
fused at the top to a flange 334 (e.g., attached to the wave
guide). The housing 330 may further include a plurality of slots
310 which pierce the housing 330 and may be adapted to
directionally propagate microwave radiation into an oil shale
deposit 206 of FIG. 2. In some embodiments, the housing 330 and
slots 310 are configured to generate substantially omni-directional
radiation (e.g., by providing substantially 180-degree radiation
from each of the wide faces 306).
[0062] In one embodiment, the housing 330 includes eight slots 310
on each of its two wide faces 306 and no slots 310 on its narrow
faces 308. Each of the slots 310 may have a slot length 312 of
2.407 inches and a slot width 314 of 0.245 inches. The housing 330
may also provide a headspace 320 between the top of the antenna 300
and the top of the uppermost slot 310-1 of approximately 3.667
inches, a vertical spacing 322 of approximately 3.667 inches, and a
bottom offset 324 between the bottom of the antenna 300 and the
bottom of the lowest slot 310-8 of approximately 3.667 inches.
Further, the slots 310 may each have a horizontal offset 326 from
the centerline 328 of the antenna 300 of approximately 0.197
inches. It will be appreciated that many shapes, sizes, quantities,
and positions of slots are possible for providing similar or
different results.
[0063] Returning to FIG. 2, in some embodiments, microwave
radiation output from the generator 220 propagates through a wave
guide 222 before reaching the antenna 224. In certain embodiments,
a flange 226 may be provided at an end of the wave guide 222 with
which the antenna 224 may be coupled to the flange 226. In one
embodiment, the antenna 224 may be engraved on the end of the wave
guide 222 past the flange.
[0064] The wave guide 222 may be any useful shape to aid in the
propagation of the microwave radiation. For example, the wave guide
222 may include a curve of approximately ninety degrees. This may
be desirable where the output of the generator 220 propagates the
microwave radiation in a direction substantially orthogonal to the
orientation of the antenna 224. In one embodiment, the wave guide
222 is a WR 340-type copper wave guide with high surface finishes.
However, it will be appreciated that the wave guide 222 may be
manufactured from any effective material (e.g., copper).
[0065] In certain embodiments, other components may be added to
assist the propagation of the microwave radiation into the oil
shale deposit 206. For example, additional antennae may be provided
in one or more locations throughout the oil shale deposit 206.
Further, it may be desirable to monitor certain characteristics of
the oil recovery system 200, and adjust the radiation
accordingly.
[0066] In some embodiments, various monitor probes (e.g.,
dielectric probes) may be placed within the oil shale deposit 206
for monitoring the amount and/or characteristics of microwave
radiation reaching certain parts of the oil shale deposit 206. For
example, monitoring devices may be used at the ground surface to
monitor the progress of oil release from the oil shale deposit 206
and the associated gasification and/or cracking of the oil shale
deposit 206 (e.g., or other constituents associated with the
kerogen in the oil shale). In one embodiment, dielectric probes are
provided to identify different constituents of a deposit by
exploiting differences in dielectric constants (e.g., water may
have a dielectric constant of approximately 80, wet sand may have a
dielectric constant of approximately 10-30, and shale may have a
dielectric constant of approximately 5-15).
[0067] In another embodiment, a compact, portable, millimeter-wave
spectrometer may be used at the ground surface to quantitatively
monitor and detect the composition of the released oil emulsion.
This quantitative monitoring may include the various proportions of
the constituents in a gaseous volatile stream as they exit the oil
transport pipe 230. Similarly, the various proportions of the
constituents in a gaseous volatile stream may be monitored after
being otherwise processed (e.g., by the oil processing system 132
of FIG. 1). For example, the volatiles may be captured in a quartz
cell at very low pressures for millimeter-wave double-resonance
spectroscopy to provide on-line dynamic data relating to the
quantitative monitoring of the volatile stream.
[0068] In still other embodiments, millimeter-wave radiation is
used for remote sensing. For example, sensors at the ground surface
may be adapted to locate potentially rich deposits of oil shale
rocks underground for exploration. This may help predict the
potential of oil before installing an oil recovery system 200.
Millimeter-wave radiation of known spectral distribution may be
sent through a transmission line to suspected sites and the
reflected radiation may be compared with the incident radiation.
The comparison may tell if the deposit is rich in oil shale. This
may provide a cost effective and reliable methodology to be used in
oil exploration, including for finding oil deposits in oil shale
underground.
[0069] In still other embodiments, the input and/or output of the
generator 220 may be monitored to determine generator efficiency,
power usage, output characteristics, etc. In any or all of the
various embodiments that include monitoring, monitored information
may be fed back to components or systems of the oil recovery system
200. In some embodiments, the information may be used to directly
or indirectly adjust characteristics of the radiation supplied to
the oil shale deposit 206. For example, components of the oil
recovery system 200 may be adjusted to change the frequency, power,
intensity, and/or other characteristics of the radiation.
[0070] In some embodiments, the antenna 224 may be enclosed within
a sheath 228. The sheath 228 may be adapted to shield the antenna
224 from externalities, like superheated steam, CO.sub.2, H.sub.2,
oil, and rock. Shielding the antenna 224 may require manufacturing
the sheath 228 from certain materials and to certain
specifications. For example, in one embodiment, the sheath 228 is
cylindrical with a ten-inch inner diameter and a wall thickness of
0.25 inches.
[0071] In certain embodiments, the sheath 228 is adapted to be
substantially transparent to a predetermined frequency of microwave
radiation. For example, certain types of silica (e.g., fused
silica) may be approximately one hundred percent transparent to the
propagation of 2.45 GHz microwave radiation. In some embodiments,
portions of the sheath 228 may include an opening which allows the
passage of the wave guide 222, pipes, cables, and/or other
components into or out from the sheath 228. These openings may be
adapted to maintain the overall seal around the antenna 224 by
using mechanical or chemical sealing components (e.g., sealing
rings, grommets, etc.).
[0072] In some embodiments, the sheath 228 is sunk into the bore
hole 202 and situated in proximity to the depth where oil will be
extracted from the oil shale deposit 206. In certain embodiments,
the generator 220 may be coupled with the outside of the sheath
228. The wave guide 222 may then be coupled between the generator
220 and the antenna 224 such that it passes through a sealed
opening in the wall of the sheath 228. In this way, a sealed
environment may be created for the propagation of the microwave
radiation.
[0073] It will be appreciated that many types and configurations of
sheath 228 are possible, according to embodiments of the invention.
For example, the sheath 228 may be manufactured in any useful
shape, size, material, thickness, etc. In some embodiments, the
sheath 228 surrounds the generator 220 and/or other components of
the oil recovery system 200. In embodiments that include multiple
antennae 224, multiple sheaths 228 may be used to surround some or
all of the antennae, individually or in groups.
[0074] In some embodiments, an oil transport pipe 230 is sunk into
the bore hole 202. Oil released from the oil shale deposit 206 may
be forced upward through the oil transport pipe 230 and into a
surface oil collector 208. In one embodiment, the oil transport
pipe 230 may have an approximately ten-inch inner diameter, may be
manufactured from corrosion-resistant steel (e.g., 316 L steel),
and may have a wall thickness of approximately 0.25 inches. It will
be appreciated that the oil transport pipe 230 may be manufactured
in any useful size and of any material capable of handling the
pressure and heat required to force the released oil into the
surface oil collector 208. Further, it will be appreciated that the
oil transport pipe 230 may include multiple pipes, insulators,
connectors, and/or other components for added effectiveness, ease
of manufacture, ease of assembly and transport, etc.
[0075] In some embodiments, the surface oil collector 208 is
situated at the surface opening of the bore hole 202. The surface
oil collector 208 may be any of the types of surface oil collectors
known in the art capable of collecting oil from the oil recovery
system 200. In certain embodiments, the surface oil collector 208
may also help seal the top of the oil transport pipe 230 and the
surrounding bore hole 202. This seal may help isolate the bore hole
202 environment, including the oil transport pipe 230, from
externalities and may help maintain pressure within the bore hole
202 and the oil transport pipe 230.
[0076] In some embodiments, an outer pipe seal-off 236 may be
provided to seal the bottom of the oil transport pipe 230. In one
embodiment, the outer pipe seal-off 236 includes openings (e.g.,
1/4-inch diameter holes) to allow the flow of released oil emulsion
into a region of the bore hole 202 above the outer pipe seal-off
236. In this way, the oil emulsion may be permitted to flow into
the oil transport pipe 230. Further, the outer pipe seal-off 236
may provide cover and support to the generator 220.
[0077] In some embodiments, the outer pipe seal-off 236 is larger
in diameter than the oil transport pipe 230. The outer pipe
seal-off 236 may be coupled to the bottom of the oil transport pipe
230 in any manner known to the art to be effective for sealing the
bottom of the outer pipe seal-off 236. The outer pipe seal-off 236
may further be coupled to the top of the sheath 228, helping to
seal the top of the sheath 228 and to couple the sheath 228 with
the oil transport pipe 230. In some embodiments, the outer pipe
seal-off 236 may include one or more openings to allow passage of
components (e.g., cables, pipes, etc.) through the outer pipe
seal-off 236 from the oil transport pipe 230 to the sheath 228. It
will be appreciated that the openings in the outer pipe seal-off
236 may be sealed in any effective way to maintain the bottom seal
of the oil transport pipe 230 and the top seal of the sheath
228.
[0078] In certain embodiments, a conduit 232 may be provided. The
conduit 232 may be situated within the oil transport pipe 230 and
may be similarly sealed (e.g., by the surface oil collector 208 at
the top and by the outer pipe seal-off 236 at the bottom). In one
embodiment, the conduit 232 may provide a sealed region within the
oil transport pipe 230 as a conduit for the power cable 212. In
this embodiment, the conduit 232 may have a five-inch inner
diameter and a wall thickness of 0.25 inches. Further, in this
embodiment, the power cable 212 may pass through the oil transport
pipe 230 via the conduit 232, thereby being shielded from the
environment in the remaining portion of the oil transport pipe
230.
[0079] It will now be appreciated that the power cable 212 may run
from the power supply 210 to the generator 220 through a sealed
environment. More specifically, in one embodiment, the power cable
212 may run from the power supply 210, through the surface oil
collector 208, into the sealed conduit 232, through a sealed
opening in the outer pipe seal-off 236, into the sheath 228,
through a sealed opening in the sheath 228, and into the generator
220.
[0080] Various embodiments may provide improved shielding and/or an
improved seal, particularly for the routing of the power cable 212
from the power supply 210 to the generator 220. In one embodiment,
the generator 220 may be coupled in a sealed way to the side of the
sheath 228 (e.g., still providing space for air cooling of the
generator). In another embodiment, a sealed conduit 232 may be
provided to enclose the power cable 212 as it routes between the
power supply 210 and the surface oil collector 208. In yet another
embodiment, a sealed conduit 232 may be provided to enclose the
power cable 212 as it routes between the outer pipe seal-off 236,
through the sheath 228, and to the generator 220.
[0081] It will be appreciated that these sealed regions and
conduits 232 may be used for routing and/or sealing components
other than the power cable 212. In some embodiments, thermal
management components are run through and/or incorporated with the
conduit 232. For example, pipes, vents, fans, and/or other
components may be used to maintain a desirable operating
temperature for the generator. In another embodiment, signal cables
are run through the conduit 232. For example, cables may be run
through the conduit 232 to communicate control signals, feedback
signals, emergency shutdown signals, remote monitoring signals,
etc.
[0082] In some embodiments, a perforated region 234 (e.g., a
perforated pipe, perforations in the oil transport pipe 230, etc.)
is provided to allow oil to flow into the oil transport pipe 230.
It will be appreciated that the perforated region 234 may be
adapted to allow the flow of oil while still maintaining pressure
within the oil transport pipe 230. In one embodiment, the
perforated region 234 is a one-meter region in the lower portion of
the oil transport pipe 230. The perforated region 234 may be
situated in proximity to the depth where oil will be extracted from
the oil shale deposit 206.
[0083] In certain embodiments, a flow ring seal 238 is provided.
The flow ring seal 238 may be coupled with and may surround the
outside of the oil transport pipe 230. Further, the flow ring seal
238 may be situated at a shallower depth than the perforated region
234 to help direct the flow of released oil into the oil transport
pipe 230.
[0084] In various embodiments, the oil recovery system 200 may be
assembled in different ways. In one embodiment, the bore hole 202
is drilled and the area surrounding the bore hole 202 (on the
surface) is reinforced with the layers of compacted soil and
concrete 204. All or a portion of the components of the oil
recovery system 200 may then be lowered into the bore hole 202 with
the exception of the power supply 210 and the surface oil collector
208.
[0085] In one embodiment, the generator 220, wave guide 222,
antenna 224, power cable 212, and sheath 228 may be pre-coupled
into a first subassembly. The oil transport pipe 230, conduit 232,
perforated region 234, and flow ring seal 238 may be pre-coupled
into a second subassembly. The power cable 212 may be passed from
the first subassembly, through a sealed opening in the outer pipe
seal-off 236, and through the conduit 232 in the second assembly.
The two subassemblies may then be fused together at the outer pipe
seal-off 236 to form a third subassembly. This third subassembly
may then be lowered into the bore hole 202 to place all the
components in the third subassembly in their appropriate locations.
The power cable 212 may then be passed through the surface oil
collector 208, and the surface oil collector 208 may be installed
to seal the top of the oil transport pipe 230 and to seal the top
of the bore hole 202. The power supply 210 may then be installed at
the ground surface and the power cable 212 may be coupled to the
power supply 210.
[0086] In other embodiments, assembly of the oil recovery system
200 may include lowering components into the bore hole 202
individually, in groups, or as subassemblies. For example, the
generator 220, wave guide 222, antenna 224, and sheath 228 may then
be sunk into the bore hole 202 before being coupled with other
components of the oil recovery system 200. Further, the shape and
size of the bore hole 202 may be related to or may dictate how the
oil recovery system 200 is assembled.
[0087] In one embodiment, the bore hole 202 is approximately
sixteen inches in diameter and one thousand feet deep. In this
embodiment, the flow ring seal 238 and outer pipe seal-off 236 have
approximately the same diameter as the bore hole 202 (i.e., sixteen
inches), and the oil transport pipe 230 and sheath 228 have
diameters of approximately ten inches. A subassembly with these
dimensions, incorporating the components of the third subassembly
described above, may fit tightly into the bore hole 202. It will be
appreciated that components of various embodiments may be modified
to fit bore holes 202 of different shapes, sizes, and depths.
[0088] Some embodiments, at least through the use of appropriately
sized and oriented components, may provide a substantially sealed
environment when installed. The substantially sealed environment
may then allow the microwave radiation to propagate into the oil
shale deposit 206, and may allow pressure from super-heated steam
to force the released oil from the oil shale deposit 206 to flow
upward through the oil transport pipe 230 and into the surface oil
collector 208. Further, certain components of the oil recovery
system 200 (e.g., the outer pipe seal-off 236, the conduit 232, and
the sheath 228) substantially protect other components of the oil
recovery system 200 (e.g., the generator 220, the antenna 224, and
the power cable 212) from coming into contact with the high
temperatures and pressures relating to the flow of released oil,
steam, and gases.
[0089] It will be appreciated that other components may be added to
the oil recovery system 200 to increase its effectiveness. In some
embodiments, multiple antennae 224 are distributed throughout the
oil shale deposit 206 to more directly irradiate certain portions
of the oil shale deposit 206. Because field intensities may
drop-off as a function of distance from the source, placing more
sources (e.g., antennae) throughout the oil shale deposit 206 may
increase the average field intensity across the oil shale deposit
206.
[0090] FIG. 4 shows an illustration of a top view of an oil shale
deposit 410 with multiple distributed antennae 440, according to
various embodiments of the invention. In some embodiments, a bore
hole 420 is located in a location central to the oil shale deposit
410. In other embodiments, the bore hole 420 is located in some
other location (e.g., for added convenience, for easier drilling,
to avoid surface uses of the land, etc.). An oil transport pipe 430
and/or other oil recovery systems and components may be situated in
or near the bore hole 420. In some embodiments, each antenna 440 is
surrounded (e.g., and shielded) by a sheath 445.
[0091] Some embodiments of the oil recovery system (e.g., oil
recovery system 200 of FIG. 2) include one or more radiation
handling components situated in the oil shale deposit (e.g., oil
shale deposit 206 of FIG. 2). The radiation handling components may
be adapted to direct radiation in the oil shale deposit 410. For
example, the radiation handling components may reflect, deflect,
focus, polarize, or otherwise affect the direction or other
characteristics of the radiation as it passes through the
deposit.
[0092] In various embodiments, oil recovery systems like the one
shown in FIG. 4 are used to recover oil from oil shale deposits 410
or reservoirs, where the oil is difficult to access. For example,
the oil shale deposit 410 or reservoir may be at the site of a
previously drilled well, a spent well, an old serviced and
abandoned well, a difficult-to-access find, etc. In these
embodiments, water (e.g., some a measured amount) may be pumped
into the vicinity of the oil shale deposit 410. A number of
microwave sources (e.g., klystrons, antennae, etc.) and/or
accessories may be placed at appropriate depths and locations to
generate microwaves adapted to be readily absorbed by the water.
For example, klystrons may be provided, each klystron being adapted
to generate approximately 2.45 GHz radiation at approximately 100
kilowatts of continuous-wave power.
[0093] The absorption of the radiation by the water may cause the
water to heat and generate steam. The steam, along with the in situ
microwave heating of the oil in the oil shale deposit, may cause
the oil emulsion to be forced into an oil transport pipe 430. In
various embodiments, the oil transport pipe 430 may be suitably
oriented in an existing (e.g., previously drilled) well or the
wells may be dug out in appropriate orientations and/or depths.
[0094] It will be appreciated that other additional components may
improve the efficacy of the oil recovery system. For example, only
a portion of the microwave radiation may be absorbed by the oil
shale deposit 410, and the remainder may be essentially wasted.
However, it may be possible to provide one or more reflectors to
reflect the unabsorbed radiation back into the deposit. This may
increase the amount of radiation absorbed by the deposit and
decrease the amount of waste.
[0095] FIG. 5A shows an illustration of a top view of an oil shale
deposit 510 with a single antenna 540 and a single reflector 550,
according to various embodiments of the invention. An oil transport
pipe 530 is situated in a bore hole 520 located in the oil shale
deposit 510. The reflector 550 is situated outside the bore hole
520. In some embodiments, the reflector 550 surrounds the bore hole
520 at some distance. It will be appreciated that the reflector 550
may be any useful shape and any useful distance from the bore hole
520.
[0096] As radiation leaves the antenna 540, some is absorbed by the
oil shale deposit 510 (e.g., causing it to heat), while other
radiation is not absorbed. In fact, a low dielectric loss in some
oil shale deposits 510 may result in a low percentage of the
radiation being absorbed. However, when the unabsorbed radiation
reaches the reflector 550, it may be reflected back into the oil
shale deposit 510 for increased absorption. The reflector 550 may
be manufactured from any suitable material for reflecting the
radiation. In one embodiment, the reflector 550 is an aluminum
cylinder. In certain embodiments, the reflector 550 is further
treated (e.g., coated) to be better compatible with the environment
of the oil shale deposit 510 (e.g., to avoid corrosion).
[0097] FIG. 5B shows an illustration of a top view of an oil shale
deposit 510 with a single antenna 540, an outer reflector 550, and
an inner reflector 560, according to various embodiments of the
invention. An oil transport pipe 530 is situated in a bore hole 520
located in the oil shale deposit 510. The outer reflector 550 is
situated outside the bore hole 520. In some embodiments, the outer
reflector 550 surrounds the bore hole 520 at some distance. The
inner reflector 560 may also be situated outside the bore hole 520,
but in closer proximity to the bore hole 520 than the outer
reflector 550. In some embodiments, the inner reflector 560
surrounds the bore hole 520 at a relatively close distance. The
inner reflector 560 is manufactured to be substantially transparent
to certain microwave radiation in one direction, while being
substantially reflective to the microwave radiation in the other
direction. For example, the inner reflector 560 may include
multiple layers (e.g., which may be separated) to provide this
functionality.
[0098] As radiation leaves the antenna 540, it passes through the
inner reflector 560 in the direction in which the inner reflector
560 is substantially transparent to the radiation. As the radiation
passes into the oil shale deposit 510, some is absorbed by the oil
shale deposit 510, while other radiation is not absorbed. When the
unabsorbed radiation reaches the outer reflector 550, it may be
reflected back into the oil shale deposit 510 for increased
absorption. On the second pass, additional radiation may be
absorbed by the oil shale deposit 510 and some radiation may still
remain unabsorbed. The remaining unabsorbed radiation may come back
in contact with the outside of the inner reflector 560 (e.g., the
direction in which the inner reflector 560 is substantially
reflective to the radiation). The remaining unabsorbed radiation
may be once again reflected back into the oil shale deposit 5 10.
In this way, the radiation may essentially remain trapped in the
oil shale deposit 510, potentially increasing the efficiency of
absorption by the oil shale deposit 510.
[0099] FIG. 5C shows an illustration of a top view of an oil shale
deposit 510 with multiple antennae 540, an outer reflector 550, and
an inner reflector 560, according to various embodiments of the
invention. An oil transport pipe 530 is situated in a bore hole 520
located in the oil shale deposit 510. The outer reflector 550 is
situated outside the bore hole 520. In some embodiments, the outer
reflector 550 surrounds the bore hole 520 at some distance. The
inner reflector 560 may also be situated outside the bore hole 520,
but in closer proximity to the bore hole 520 than the outer
reflector 550. In some embodiments, the inner reflector 560
surrounds the bore hole 520 at a relatively close distance. As
illustrated, the antennae 540 may all be located outside the bore
hole 520.
[0100] In some embodiments, the antennae 540 are located outside
the bore hole 520, between the inner reflector 560 and the outer
reflector 550. Because all the antennae 540 may be situated on one
side of the inner reflector 560, the inner reflector 560 may be
manufactured to be substantially reflective to certain microwave
radiation from either one or both directions. In this way,
radiation from any or all of the antennae 540 may reflect between
the inner reflector 560 and the outer reflector 550 to be more
efficiently absorbed by the oil shale deposit 510.
[0101] FIG. 6 provides a flow diagram of a method for oil recovery,
according to various embodiments of the invention. The method 600
begins at block 610 by generating microwave radiation. For example,
the microwave radiation may be generated by a klystron or other
microwave generator. As discussed above, in some embodiments, the
radiation is generated at block 610 in situ. For example, the
radiation may be generated from a depth of approximately one
thousand feet, rather than attempting to propagate the microwave
radiation from the surface through one thousand feet of depth
(e.g., via a wave guide).
[0102] The microwave radiation generated at block 610 may then be
transmitted at block 620 into an oil shale deposit. In some
embodiments, the microwave radiation is transmitted at block 620 by
an antenna, adapted to transmit radiation at a particular microwave
frequency. The antenna may be further adapted to transmit radiation
at a certain amplitude, polarity, etc. In some embodiments, the
generation at block 610 and/or the transmission at block 620 may be
tunable based on one or more conditions relating to the oil
recovery.
[0103] When the radiation propagates into the oil shale deposit at
block 620, the oil shale may be heated. Environmental changes may
result from the heating. For example, water trapped within the
deposit may become super-heated steam. The pressure of the steam
may cause cracking and other events within the oil shale. For this
and other reasons, oil and other gases may be released from the oil
shale. Pressure from released gases may also cause the oil and
other released constituents to be forced from the oil shale deposit
into a lower pressure environment.
[0104] At block 630, the released oil may be extracted and/or
collected. Extracting the oil at block 630 may include providing a
lower pressure environment (e.g., piping in a bore hole) into which
the oil and other released constituents may flow. The oil may then
be pumped or otherwise forced to the surface for collection. In
some embodiments, pressure from the super-heated steam may force
the released oil up to the surface for collection.
[0105] It will be appreciated that the released oil may not be pure
or refined. Rather, the released oil may contain impurities, or it
may be mixed with other liquids, solids, or gases. For this and
other reasons, it may be desirable to refine and/or process the oil
at block 640. Refining the oil at block 640 may remove or separate
impurities (e.g., water, CO.sub.2, CH.sub.4, C.sub.2H.sub.6, oxides
of sulfur, etc.), or perform any other function useful for
improving the usefulness of the released oil for some purpose. For
example, processing the oil may include transporting the oil or
other constituents to another location, or recycling a portion of
the released constituents to provide power for steps of the oil
recovery method 600.
[0106] In some embodiments, certain information may be monitored at
block 650 and fed back to steps of the method 600 for use in
adapting the method to changing conditions. For example, it may be
desirable to adapt characteristics of the generated radiation, how
or where the radiation is transmitted into the oil shale deposit,
how released constituents are processed, etc.
[0107] FIG. 7 provides a flow diagram of a method for oil recovery
from an existing reservoir site, according to various embodiments
of the invention. The method 700 begins at block 710 by providing
an oil collection system. At block 720, water is pumped into an
underground oil reservoir site. Microwave radiation is generated at
block 730 at a power and/or frequency adapted for converting the
pumped water into steam.
[0108] At block 740, the microwave radiation is transmitted into
the reservoir site using multiple in situ radiation sources. The
radiation may be absorbed by the water, causing the water to
convert to steam. The same or other radiation (e.g.,
radiofrequency) may be used to heat the oil in the oil reservoir
site. Pressure from the steam may cause the oil to be forced into
the oil collection system.
[0109] Embodiments of Oil Refinement Systems and Methods
[0110] In various embodiments of the invention, heating an oil
shale deposit may cause an oil emulsion to be released. For
example, volatile products (e.g., water, steam, hydrogen, methane,
etc.) may be formed underground and may become mixed with the
released oil. In fact, any type of oil extraction from an
underground oil source (e.g., oil shale or a reservoir) may produce
an oil emulsion containing both oil and other constituents.
Additionally, the released oil may, in some cases, contain large
macromolecules, which may cause the released oil to be heavy,
viscous, and difficult to transport to the ground surface. For at
least these reasons, oil (or an oil emulsion) extracted from a site
may require certain processing before it may be used in various
applications. The processing may be used to refine the oil,
including removing impurities and breaking down macromolecules.
[0111] It will be appreciated that it may be desirable to
preprocess the emulsion while still underground. In this way, the
extracted product may be better compatible with direct shipment to
refineries or other uses. FIG. 8 shows a simplified illustration of
an oil recovery system, modified for preprocessing of the recovered
oil, according to various embodiments of the invention. The oil
recovery system 800 may include all the same or similar components
to those in the oil recovery system 200 of FIG. 2, including the
oil transport pipe 230, the generator 220, the antenna 224, and the
surface oil collector 208. Therefore, it will be appreciated that
some or all of the additional components of the oil recovery system
800 may be additions or modifications to the oil recovery system
200 of FIG. 2.
[0112] In some embodiments, the generator 220 is adapted to provide
a second radiation output, other than the radiation transmitted
into the oil shale deposit 206. For example, the second radiation
output may have the same or different radiation characteristics,
including frequency, polarization, amplitude, etc. The
characteristics of the second radiation output may be determined as
a function of the type of refinement desired. For example, it may
be desirable to set the radiation characteristics to gasify certain
constituents of the released oil emulsion, to separate the oil from
the non-oil constituents, to break down large macromolecules in the
oil, etc. In one embodiment, the second radiation output is at the
same frequency as the first radiation output (e.g., 2.45 GHz), but
a significantly lower amplitude (e.g., two to five kilowatts of
power).
[0113] It will be appreciated that many ways are possible for
generating the two outputs from a single generator 220 or microwave
generation system. For example, a single generation system may
include multiple generators, which may or may not be collocated. In
another example, a single generator may use various components
(e.g., optics, filters, transformers, antennae, etc.) to change the
characteristics of the radiation passing through one or both
outputs. It will be further appreciated that similar or different
techniques may be used to generate more than two radiation
outputs.
[0114] In some embodiments, the second radiation output propagates
through a wave guide 822. In one embodiment, the wave guide 822 is
a WR 284-type wave guide. In some embodiments, the end of the wave
guide 822 is coupled with a window 826. The window 826 may be
adapted to be substantially transparent to the second radiation
output coming from the generator 220. In one embodiment, the window
826 is manufactured from high-density polyethylene with substantial
transparency to 2.45 GHz microwave radiation.
[0115] The window 826 may further be manufactured or installed such
that the window 826 may handle the temperatures, pressures, and
other environmental conditions which may at times be present within
the oil transport pipe 230. For at least this reason, the coupling
between the wave guide 822 and the window 826 may form a seal or
may be enclosed within a sealing assembly 824. In one embodiment,
the sealing assembly 824 may be a flange "O"-ring assembly.
[0116] In some embodiments, a shield 828 is provided between the
window 826 and the contents of the oil transport pipe 230. Certain
embodiments of the shield 828 are substantially opaque to the
output radiation passing through the window 826, thereby preventing
the radiation from reaching the contents of the oil transport pipe
230 when engaged. Other embodiments of the shield 828 are further
adapted to protect the window 826 from certain conditions within
the oil transport pipe 230. For example, when the oil level gets
too close to the window 826, it may be desirable to engage (e.g.,
close) the shield 828 over the window 826 to protect the window 826
from being damaged by exposure to the contents of the oil transport
pipe 230 (e.g., the heated oil and other constituents).
[0117] In some embodiments, the shield 828 is electrically
controlled, such that it may be opened and closed (or otherwise
moved out of the way) using electromechanical or similar control
mechanisms. For example, the shield 828 may include a set of
louvers placed in parallel with one another (like window blinds)
which may be rotated by a motor. In certain embodiments, some or
all of the control mechanisms for the shield 828 may be located
remotely to the shield 828. In one embodiment, a switch may be
located in proximity to the ground surface in operative
communication with a motor located at the shield 828. The switch at
the ground surface may be used to remotely open and close the
shield 828. In this way, it may be possible to adjust the amount
and timing of radiation which reaches the contents of the oil
transport pipe 230 without directly controlling the output of the
generator 220.
[0118] By allowing the second radiation output to flow into the oil
transport pipe 230, the second radiation output may be absorbed by
any oil emulsion that has collected within the oil transport pipe
230. When the second radiation output is absorbed, the oil emulsion
may release water, hydrogen, steam, light hydrocarbons (e.g.,
methane and ethane), and other constituents of the emulsion. In
this way, the oil may be refined and/or separated from other
constituents of the oil emulsion. The processed (e.g., refined) oil
may be forced up the oil transport pipe 230 separately from the
other components released from the oil emulsion.
[0119] Embodiments of the oil recovery system 800 include an oil
exit pipe 830 for allowing the oil to escape from the oil transport
pipe 230. In certain embodiments, the oil may then be collected at
the surface in a surface collector 208 in processed form. In some
embodiments, a volatiles exit pipe 840 may be provided to allow the
escape of some or all of the constituents of the oil emulsion other
than the processed oil. In certain embodiments, the non-oil
constituents may then be collected. For example, the non-oil
constituents may be collected in a separate surface collection unit
or in a separate area of the surface collector 208. In certain
embodiments, either or both of the volatiles exit pipe 840 and the
oil exit pipe 830 may include a plurality of pipes or other
transport components.
[0120] It will be appreciated that the other components may be
processed and/or transported for use in other applications. For
example, the gaseous products may contain fuels that can be used to
provide electricity. Additionally, energy generated from those
other components (e.g., through conversion into fuel, by using the
gas flow to generate power, etc.) may be recycled into the power
supply 210 to improve the efficiency of the oil recovery system
800.
[0121] It will be appreciated that other types of oil refinements
systems are possible according to embodiments of the invention.
FIG. 9 shows a simplified illustration of a partial oil recovery
system, modified with a generator 920 for preprocessing of the
recovered oil, according to various embodiments of the invention.
In some embodiments, the partial oil recovery system 900 includes
components and/or functionality similar to the oil recovery system
of FIG. 2. In other embodiments, the partial oil recovery system
900 includes any components and/or functionality useful for
extracting an oil emulsion into an oil transport pipe 230.
[0122] In some embodiments, the generator 920 is adapted to provide
multiple radiation outputs. In certain embodiments, the generator
920 may be provided in addition to a first generator (e.g., like
the generator 220 of FIGS. 2 and 8). It will be appreciated that,
in embodiments where there are multiple generators (e.g., generator
920 and generator 220 of FIG. 8), each generator may be powered by
the same or different power supplies 210. In certain embodiments, a
single power supply 210 (or power management system) provides
multiple outputs to the multiple generators. In other embodiments,
some or all of the generators are coupled with separate power
supplies.
[0123] The radiation outputs may have the same or different
radiation characteristics from one another, including frequency,
polarization, amplitude, etc. The characteristics of the second
radiation output may be determined as a function of the type of
refinement desired. For example, it may be desirable to set the
radiation characteristics to gasify certain constituents of the
released oil emulsion, to separate the oil from the non-oil
constituents, to break down large macromolecules in the oil, etc.
In one embodiment, the second generator is a magnetron, adapted to
generate approximately 2.45 GHz at approximately five kilowatts of
power. In another embodiment, multiple generators 920 are provided,
each being adapted to generate one or more radiation outputs.
[0124] In some embodiments, the radiation outputs propagate through
wave guides 822 (e.g., WR 284-type wave guides). In certain
embodiments, the ends of the wave guides 822 are coupled with
windows 826. The windows 826 may be adapted to be substantially
transparent to the radiation outputs coming from the generator 920.
In one embodiment, the windows 826 are manufactured from
high-density polyethylene with substantial transparency to 2.45 GHz
microwave radiation.
[0125] The windows 826 may further be manufactured or installed
such as to handle the temperatures, pressures, and other
environmental conditions which may at times be present within the
oil transport pipe 230. For at least this reason, the coupling
between the wave guides 822 and the windows 826 may form a seal or
may be enclosed within sealing assemblies 824. In one embodiment,
the sealing assemblies 824 include flange "O"-ring assemblies.
[0126] In some embodiments, shields 828 are provided between the
windows 826 and the contents of the oil transport pipe 230. Certain
embodiments of the shields 828 are substantially opaque to the
output radiation passing through the windows 826, thereby
preventing the radiation from reaching the contents of the oil
transport pipe 230 when engaged. Other embodiments of the shields
828 are further adapted to protect the windows 826 from certain
conditions within the oil transport pipe 230.
[0127] For example, when the oil level in the oil transport pipe
230 is below the lower window, it may be desirable to engage (e.g.,
close) the upper shield 828-1, thereby effectively closing the
upper window 826-1. This may cause microwave radiation to be
transmitted only from the lower window 826-2. When the oil level
rises too close to the level of the lower window 826-2, it may be
desirable to engage the lower shield 828-2 over the lower window
826-2 to protect the lower window 826-2 from being damaged by
exposure to the contents of the oil transport pipe 230 (e.g., the
heated oil and other constituents). The upper shield 828-1 may then
be disengaged from the upper window 826-1, thereby effectively
re-opening the upper window 826-1 and causing microwave radiation
to be transmitted only from the upper window 826-1.
[0128] In some embodiments, some or all of the shields 828 are
electrically controlled, such that it may be opened and closed (or
otherwise moved out of the way) using electromechanical or similar
control mechanisms. In certain embodiments, some or all of the
control mechanisms for the shields 828 may be located remotely to
the shields 828. In this way, it may be possible to adjust the
amount and timing of radiation which is transmitted to the contents
of the oil transport pipe 230 from the various windows 826 without
directly controlling the output of the generator 920.
[0129] As in the oil recovery system 800 of FIG. 8, allowing the
radiation output or outputs to flow into the oil transport pipe 230
may cause the oil emulsion to release oil and non-oil constituents
of the emulsion. In some embodiments, oil may exit through an oil
exit pipe 830 and non-oil constituents may exit through a volatiles
exit pipe 840. In certain embodiments, the oil and or non-oil
constituents may then be collected in a surface collector 208.
[0130] FIG. 10 shows a simplified illustration of a partial oil
recovery system, modified with a generator 920 and a perforated
separator 1006 for preprocessing of the recovered oil, according to
various embodiments of the invention. In some embodiments, the
partial oil recovery system 1000 includes components and/or
functionality similar to the oil recovery system of FIG. 2. In
other embodiments, the partial oil recovery system 1000 includes
any components and/or functionality useful for extracting an oil
emulsion into an oil transport pipe 230.
[0131] In some embodiments, the generator 920 is adapted to
generate a radiation output. In certain embodiments, the generator
920 is provided in addition to a first generator (e.g., like the
generator 220 of FIGS. 2 and 8). The radiation outputs may have the
same or different radiation characteristics from one another,
including frequency, polarization, amplitude, etc. The
characteristics of the second radiation output may be determined as
a function of the type of refinement desired. For example, it may
be desirable to set the radiation characteristics to gasify certain
constituents of the released oil emulsion, to separate the oil from
the non-oil constituents, to break down large macromolecules (e.g.,
by catalytic action) in the oil, etc. In one embodiment, the second
generator is a magnetron, adapted to generate approximately 2.45
GHz at approximately five kilowatts of power.
[0132] It may be desirable, in some cases, to locate the generator
920 at the ground surface, or otherwise remotely to the oil
transport pipe 230. In some embodiments, the radiation output
propagates into the oil transport pipe 230 through a wave guide 822
(e.g., a WR 284-type wave guide). In certain embodiments, the end
of the wave guide 822 is coupled with a window 826. The window 826
may be adapted to be substantially transparent to the radiation
outputs coming from the generator 920. In one embodiment, the
window 826 is manufactured from high-density polyethylene with
substantial transparency to 2.45 GHz microwave radiation.
[0133] The window 826 may further be manufactured or installed such
as to handle the temperatures, pressures, and other environmental
conditions which may at times be present within the oil transport
pipe 230. For at least this reason, the coupling between the wave
guide 822 and the window 826 may form a seal or may be enclosed
within a sealing assembly 824. In one embodiment, the sealing
assembly 824 includes a flange "O"-ring assembly.
[0134] In some embodiments, a shield 828 is provided between the
window 826 and the contents of the oil transport pipe 230. Certain
embodiments of the shield 828 are substantially opaque to the
output radiation passing through the window 826, thereby preventing
the radiation from reaching the contents of the oil transport pipe
230 when engaged. Other embodiments of the shield 828 are further
adapted to protect the window 826 from certain conditions within
the oil transport pipe 230.
[0135] In some embodiments, the oil transport pipe 230 includes a
perforated separator 1006. The perforated separator 1006 may
provide one or more functions, including dividing the oil transport
pipe 230 into an upper region 1002 and a lower region 1004. An oil
emulsion may enter the lower region 1004 of the oil transport pipe
230 (e.g., through the perforated region 234 of FIG. 2). Pressure
from super-heated steam or some other source may then force the oil
emulsion upward through the oil transport pipe 230 from the lower
region 1004 to the upper region 1002 for surface collection by a
surface collector 208. It is worth noting that, where the oil
transport pipe includes a perforated region (e.g., the perforated
region 234 of FIG. 2), perforations in the perforated separator
1006 may be similar to or different from perforations in the
perforated region of the oil transport pipe 230.
[0136] It will be appreciated that, while the perforations in the
perforated separator 1006 may be sized large enough to permit the
flow of oil and/or other constituents from the lower region 1004 to
the upper region 1002, the perforations may be sized small enough
to substantially prevent microwave radiation propagated into the
lower region 1004 from leaking into the upper region 1002. For
example, in one embodiment, the perforated separator is
manufactured with perforations having approximately 1/8-inch
diameters. This size of perforation may be substantially opaque to
2.45 GHz radiation. As such, the perforations may cause radiation
coming through the window 826 to be substantially trapped in the
lower region 1004, while still allowing the flow of oil into the
upper region 1002.
[0137] In certain embodiments, wave guide 822, the window 826, the
shield 828, and/or the sealing assembly 824 are installed within an
opening in the perforated separator 1006. This may allow
propagation of radiation from the generator 920 into the lower
region 1004 of the oil transport pipe 230 through the wave guide
822 and the window 826 (i.e., without being blocked by the
perforated separator 1006). Using the sealing assembly 824 in this
way may, for example, create a seal at the opening in the
perforated separator 1006, or may shield the wave guide 822 and/or
window 826 from direct contact with the perforated separator
1006.
[0138] In one embodiment, the distance 1050 from the ground surface
204 to the window 826 (and the perforated separator 1006) is
approximately 100 feet. As microwave radiation propagates through
the wave guide 822, there may be significant attenuation. As such,
situating the window 822 and the perforated separator 1006
relatively close to the ground surface level 204 may allow
propagation of radiation into the lower region 204 without
significant attenuation.
[0139] As in the oil recovery system 800 of FIG. 8 and the partial
oil recovery system 900 of FIG. 9, allowing the radiation output or
outputs to flow into the oil transport pipe 230 may cause the oil
emulsion to release oil and non-oil constituents of the emulsion.
In some embodiments, oil may exit through an oil exit pipe 830 and
non-oil constituents may exit through a volatiles exit pipe 840. In
certain embodiments, the oil and or non-oil constituents may then
be collected in a surface collector 208.
[0140] FIG. 11 provides a flow diagram of a method for processing
oil emulsions to separate oil and non-oil constituents of the
emulsion, according to various embodiments of the invention. The
method 1100 begins at block 1110 by receiving an oil emulsion at an
oil extraction system (e.g., in an oil transport pipe). The oil
emulsion may be received in any effective way. In some embodiments,
the oil emulsion is received by a process similar to that of method
600 of FIG. 6 (e.g., by performing steps 610, 620, and 630).
[0141] At block 1120, microwave radiation is generated, the
microwave radiation being of a type adapted to refine an oil
emulsion. For example, the microwave radiation may be five-to-100
kilowatt microwave (e.g., 2.45 GHz) radiation. The microwave
radiation may be transmitted into the oil emulsion at block 1130 to
process the oil emulsion. For example, heating the oil emulsion
with the radiation may cause oil and non-oil constituents of the
emulsion to separate. The oil may be collected at block 1140 by a
first collection system, and the non-oil constituents may be
collected at block 1150 by a second collection system. In some
embodiments, the first and second collection systems may be
separate regions of one collection system.
[0142] In some embodiments, the composition of the oil emulsion may
be analyzed at block 1160. For example, the composition of the oil
emulsion may be analyzed before and/or after processing.
Information from the analysis may, in certain embodiments, be fed
back to other steps of the method 1100 to adjust, tune, or
otherwise affect performance of the step of the method 1100. For
example, the information may be fed back to block 1120 or block
1130 to affect the generation and/or transmission of radiation,
respectively.
[0143] FIG. 12 provides a flow diagram of a method for processing
heavy oil into lighter oil, according to various embodiments of the
invention. The method 1200 begins at block 1210 by receiving heavy
oil at an oil extraction system (e.g., in an oil transport pipe).
The heavy oil may be received in any effective way. For example,
large reservoirs of heavy oil may exist in multiple locations
around the world.
[0144] At block 1220, microwave radiation is generated, the
microwave radiation being of a type (e.g., continuous-wave or
pulse) adapted to refine heavy oil. For example, large
macromolecules (e.g., of hydrocarbons) may cause heavy oil to be
highly viscous and difficult to transport and/or extract. The
microwave radiation may be configured (e.g., tuned) to break up the
large macromolecules in the oil into smaller molecules. For
example, microwave radiation, coupled with effects from trace
amounts of elements in the vicinity of a well (e.g., silicates,
pyrites, phosphates, manganese, nickel, etc.) may catalyze the
reaction rates of conversion from heavy oil into lighter (e.g.,
more liquidous) oil. The microwave radiation may be transmitted
into the oil emulsion at block 1230. The resulting lighter oil may
be collected at block 1240 by a collection system.
[0145] In some embodiments, the composition of the oil may be
analyzed at block 1250. For example, the composition of the oil may
be analyzed before and/or after refining. Information from the
analysis may, in certain embodiments, be fed back to other steps of
the method 1200 to adjust, tune, or otherwise affect performance of
the step of the method 1200. For example, the information may be
fed back to block 1220 or block 1230 to affect the generation
and/or transmission of radiation, respectively.
[0146] It should be noted that the methods, systems, and devices
discussed above are intended merely to be examples. It must be
stressed that various embodiments may omit, substitute, or add
various procedures or components as appropriate. For instance, it
should be appreciated that, in alternative embodiments, the methods
may be performed in an order different from that described, and
that various steps may be added, omitted, or combined. Also,
features described with respect to certain embodiments may be
combined in various other embodiments. Different aspects and
elements of the embodiments may be combined in a similar manner.
Also, it should be emphasized that technology evolves and, thus,
many of the elements are examples and should not be interpreted to
limit the scope of the invention.
[0147] Specific details are given in the description to provide a
thorough understanding of the embodiments. However, it will be
understood by one of ordinary skill in the art that the embodiments
may be practiced without these specific details. For example,
well-known processes, algorithms, structures, and techniques have
been shown without unnecessary detail in order to avoid obscuring
the embodiments.
[0148] Merely by way of example, many additions or modifications
are possible to any of the oil recovery systems of FIGS. 1, 2, 8,
9, and 10 without departing from embodiments of the invention. For
example, additional conduits may be passed from the ground surface
to one or more generators and/or other components of the systems
for added functionality (e.g., a conduit may provide cool air to
cool generator 220 of FIG. 2 during operation).
[0149] Also, it is noted that the embodiments may be described as a
process which is depicted as a flow diagram or block diagram.
Although each may describe the operations as a sequential process,
many of the operations can be performed in parallel or
concurrently. In addition, the order of the operations may be
rearranged. A process may have additional steps not included in the
figure.
[0150] Having described several embodiments, it will be recognized
by those of skill in the art that various modifications,
alternative constructions, and equivalents may be used without
departing from the spirit of the invention. For example, the above
elements may merely be a component of a larger system, wherein
other rules may take precedence over or otherwise modify the
application of the invention. Also, a number of steps may be
undertaken before, during, or after the above elements are
considered. Accordingly, the above description should not be taken
as limiting the scope of the invention.
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