Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
BACKGROUND OF THE INVENTION
The present invention relates to the treatment of hydro-
carbon material with electromagnetic energy, and more particularly
to a method and apparatus for recovering fractions from hydro-
carbon material, facilitating the removal and cleansing of hydro-
carbon fluids, insulating storage vessels, and cleaning storage
vessels and pipelines.
The existing techniques of heating hydrocarbon material
such as coal, lignite, peat, and kerogen or hydrocarbon fluids,
i.e., those having a kinematic viscosity in the range of about 20
seconds Saybolt Universal to about 500,000 seconds Saybolt Universal
at 100F, with conventional thermal conduction methods using steam,
hot water, ~lectric coils, plates, piping or tracers has only met
with limited success due to the poor thermal conductivity of the
hydrocarbon fluid. Further, even with extremely high temperature
gradients and therefore energy expenditure these techniques still
fail to æhieve penetration into the fluid to any great distance
when it is immobile. Hydrocarbon materials such as coal, oil sh~le
and tar sands remain locked in geological formations for somewhat
similar reasons, although some modest degree of success has been
achieved in in situ removal by using fire floods, solvents, poly-
mers, bacteria, water floods and steam floods, so-called "Huff
and Puff."
The physical characteristics of oil sands oil, bitumen,
oil shale, peat, and lignite, are quite different from those
of conventional crude oil. The oil sands bitumen, oil shale,
peat and lignite is much heavier and much more viscious than
conventional crude oil, sothat under reservoir conditions it is
essentially immobile. In fact, the oil sands bitumen, oil shale,
peat and lignite has essentially the consistency of tar and can be
induced to flow only if the reservoir conditions are suitably
altered, for instance by raising its temperature. Particularly
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in the last two decades, a variety of in situ recovery tech-
niques have been studied, including such methods as the under~
ground injection of steam, hot water and hot gas, ignition of
the oil within the formation, and underground atomic explosions.
A common goal of these techniques is to transfer heat to the
oil formation to raise the temperature of the very viscious oil
sufficiently above the in situ temperature of lO to 15~C so
that the oil can flow and be swept from the host formation by
a suitable pressurized gas or o-ther pressurized fluid driving
agent. Since the formation is quite impermeable and has very
low thermal conductivity, heat transfer by conduction and con-
vection, as in the foregoing methods, is a very slow process.
Moreover, control of the movement of -the injected hea-ting fluid
within the formation is difficult so that a major unsolved prob-
lem of in situ technology is that of directing the fluid to
the~egion which is to be heated, this region being generally
the volume of the formation between a system o~ injection and
production wells.
United States Patent Re. 31,241, reissued on May 17,
1983, discloses a method and apparatus for controlling the fluency
of hydrocarbon fluids by using electromagnetic energy. In accor-
dance with the method, hydrocarbon fluidpresent in a geological
substrate or container is heated by electromagnetic energy in
the frequency range of from about 300 megahertz to about 300
gigahertz to release the hydrocarbon fluid by increasing its
fluency. The released hydrocarbon fluid is then removed. A
heating system for an oil burner and an apparatus for increasing
the fluency by heating a contained hydrocarbon fluid is also
disclosed.
Heating with RF waves is generally an absorptive heat-
ing process which results from subjecting polar molecules to a
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high frequency electromagnetic field. As the polar molecules
seek to align themselves with the alternating polarity of the
electromagnetic field, work is done and heat is generated
and absorbed. When RF energy is applied to hydrocarbons
which are trapped in a geological formation, the polar molecules,
i.e., the hydrocarbons and connate water, are heated selectively,
while the non-polar molecules of the formation are virtually
transparent to the RF energy and absorb very little of the energy
supplied.
Unlike steam flooding, which depends on pressure to
maintain temperature, RE' waves can produce very high temperatures
within hydrocarbon materials, such as kerogen in shale formations,
without requiring pressure. So called "thief zones" which channel
off steam from the desired payzone or seam with conventional
techniques are of minor consequence in the case of RF waves
since most of the energy will be absorbed in the payzone or
seam to which it is directed.
There are numerous storage stock tanks, ship bunkers,
pipelines, tankers and vessels which contain varying amounts of
high viscosity oil which it is economically impractical to
salvage. The high viscosity oil and sludge found at the bottom
of oil tankers is presently removed by bulldozers which gain
access to the hold of the tanker through an opening created in
the hull. After removal of the sludge, the hull is resealed.
This process is time consuming, expensive and wasteful.
The present invention represents an improvement over
the method and apparatus disclosed in the aforementioned reissue
patent for facilitating the removal of hydrocarbon fluids as
well as providing a novel method and apparatus for recovering
fractions from hydrocarbon materials, facilitating the removal
and cleansing of hydrocarhon fluids, insulating storage vessels,
and cleaning storage vessels and pipelines.
SUMMARY OF THE INVEMTION
It is an object of the present invention to provide
an improved method and apparatus for heating hydrocarbon material
with electromagnetic energy.
It is a further object of the present invention to pro-
vide a method and apparatus for separating hydrocarbon material
into fractions.
It is a still further object of the present invention
to provide a method and apparatus for removing high viscosity
hydrocarbon fluids and sludge from oil tankers.
- It is a still further object of the present invention
to provide a method ~d apparatus for producing clean oil from
the contaminated oil obtained from a wellbore.
It is a still further object of the present invention
to provide an improved method and apparatus for removing paraffin
from the surfaces of oil storage tanks, transfer piping, heat
exchangers, pipelines, and separators.
It is a still further object of the present invention
to provide a method and apparatus capable of retorting materials
such as coal, oil shale, peat, lignite, tar and oil sands,
and sour crudes to remove moisture, sulfur, gases, ash and
provide clean oil.
It is a still further object of the present invention
to provide a method and apparatus for in situ separation and
removal of hydrocarbons, sulfur, water and other constituents
from geological substrates of coal, peat, lignite, oil shale,
tar sand and oil.
It is a still further object of the present invention
to provide a method and apparatus for decreasing the pour point
of a hydrocarbon fluid.
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It ls a still further object of the present invention
to provide a method and apparatus for removing rust and scale
from the metal surfaces of storage vessels.
It is a still further object of the present invention
to create an automatic insulating layer as required for a stor-
age vessel from the hydrocarbon fluid present in the vessel and
eliminate the need to externally insulate the storage vessel.
It is a still further object of the present invention
to provide a method and apparatus for separating oil from an
oil, sediment and water hydrocarbon fluid emulsion to effect-
ively de-emulsify and desulfurize the hydrocarbon fluid.
It is a still further object of the present invention
to provide a method and apparatus which produces a high quality
char from coa] and petroleum coke.
It is a still further object of the present invention
to provide a method and apparatus for cleansing hydrocarbon and
otn~r fluids of bacteria and algae.
It is a still further object of the present invention
to provide a method and apparatus for increasing the yield of
hydrogen from coal.
It is a still further object of the present invention
to provide a method and apparatus for dewatering coal slurry.
It is a still further object of the present invention
to provide a method and apparatus for removing a desired hydro-
carbon, such as acetone, from waterO
It is a still further object of the present invention
to provide a method and apparatus for in situ recovery of frac-
tions from hydrocarbon material which minimizes energy loss
during the recovery.
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It is a still further object of the present invention
to provide a method and apparatus for reconstituting drilling
mud.
Briefly, in accordance with the present invention,
a method and associated apparatus is provided for recovering
fractions from hydrocarbon material, including the steps of
generating electromagnetic energy generally in the frequency
range of from about 300 megahertz to about 300 gigahertz, in
accordance with the lossiness of the materia], transmitting
the generated electromagnetic energy to the hydrocarbon mat-
erial, exposing the hydrocarbon material to the electro-
magnetic energy for a sufficient period of time to sequent-
ially separate the hydrocarbon material into fractions, and
removing the resulting fractions. ~owever, i-t should be
understood that a plurality of frequencies within the afore-
mentioned frequency range or in combination with frequencies
outside this range may be utilized in accordance with the
lossiness of the fractions to be removed. Advantageously,
the temperature of the high viscosity hydrocarbon fluid may be
precisely controlled by changing the broadcast location for
the electromagnetic energy to effectively sweep the hydro-
carbon fluid to optimize oil production while decreasing its
viscosity to facilitate its separation and removal from a
vessel. Further, the electromagnetic energy may be used to
clean storage vessels of scale and rust and a metal shield
can be placed in the storage vessel to effectively create
an insulating layer for the storage vessel from a portion
of the hydrocarbon fluid present in the vessel. It should
be understood that in addition to use with land, air and
sea vessels, including pipelines, the present invention is
also useful for underwater,underground and in situ sub-
surface applications. Moreover, a plurality of RF fre~
quencies spaced far enough apart to preclude wave cancella-
tion and having varying field strengths may be used simultan-
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eously in accordance with their absorptivity by the various
fractions to be recovered so as to achieve maximum efficiencies
in recovering the fractions.
In accordance with a broad aspect of the invention
there is provided a method for sequen~ially recovering
fractions from hydrocarbon material, comprising the steps of:
generating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 gigahertz;
transmitting the generated electromagnetic eneryy to the
hydrocarbon material for exposure thereto;
exposing the hydrocarbon material to the electromagnetic
energy;
directing the electromagnetic energy to specified portions
of the hydrocarbon material;
sensing the temperature of the hydrocarbon materlal;
controlling the generation of electromagnetic energy as a
function of the sensed temperature;
: sequentially separating the hydrocarbon material into
fractions, including water and basic sediment and hydrocarbon
liquid, as a result of exposing the hydrocarbon material to ~he
electromagnetic energy for a sufficient period of time; and
; removing the fractions resulting from exposure of the
hydrocarbon material to the electromagnetic energy.
In accordance with another broad aspect of the
invention there is provided a method of recovering fractions
from hydrocarbon material found in a geological substrate,
comprising ~he steps of:
yenerating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 gigaher~z;
transmitting the generated electromagnetic energy to the
hydrocarbon materlal;
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broadcasting the electromagnetic material energy to
specified portions of the hydrocarbon material for a sufficient
period of time to sequentially separate the hydrocarbon
material into fractions;
sensing the temperature of the hydrocarbon material;
controlling the field strength of the electromagnetic
energy, the time of exposure and the volume of the hydrocarbon
material over which the electromagnetic energy is broadcast as
; a function of the sensed temperature to vaporize the water
present in the hydrocarbon material; and
removing the resulting fractions from the hydrocarbon
material.
In accordance with another broad aspect of the
invention there is provided a method of recovering oil from a
: contained high viscosity hydrocarbon fluid including oil, water
and basic sediment, comprising the steps of:
generating electromaynetic energy in the fre~uency ranye
of from about 300 megahertz to about 300 gigahertz;
transmitting the generated electromagnetic energy toward
the hydrocarbon fluid;
deflecting the transmitted electromagnetic energy into the
hydrocarbon fluid;
sensing the temperature within the hydrocarbon fluid;
; controlling the elec~tromagnetic energy as a function of
the sensed temperature;
~:~ varying the locations in the hydrocarbon fluid to which
the electromagnetic energy is deflected to control the
temperature of various layers within the hydrocarbon fluid to
prevent any water present from reaching its ~oiling point; and
removing the separated oil from the hydrocarbon fluid
after sufficient time has elapsed after exposure of the
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hydrocarbon fluid to the electromagnetic energy to allow the
water, any sulfur present and basic sediment to separate from
the oil.
In accordance with another broad aspect of the
invention there ls provided a method of increasing the fluency
of hydrocarbon fluid present in tankers, barges and similar
vessels to facilitate removal thereof, comprising the steps of 5
generating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 gigahertz;
transmitting the electromagnetic energy to the hydrocarbon
fluid through a ~lexible wavegulde and applicator;
; coupling the flexible waveguide to a manhole in the vessel
with a manhole sealing means to prevent the loss of the
: deflected electromagnetic energy which is transmitted into the
hydrocarbon fluld and prevent the entrance and exit of gases
and liquids;
: deflecting the transmitted electromagnetic energy into the
hydrocarbon fluld from a deflector positloned within the
applicator to heat the hydrocarbon fluid and decrease lts
viscosity; and
varying the location of the defle~tor within the
applicator to concentrate the electromagnetlc energy at varlous
levels within the hydrocarbon fluid to effectlvely heat all of
. the hydrocarbon fluid pre~ent.
: According to a another broad aspect of the invention ~:.
~ there is provided a method of removing rust and scale buildup
:` from the walls o~ barges, oil tankers, vessels, condenser tubes
and other metal surfaces, comprislng the steps o~,
generating electromagnetic energy in the ~requency range
; 30 of from about 300 megahertz to about 300 gigahertz;
providlng a waveguide for propagation of the
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72385-1
electromagnetic energy into the vessel
providiny a radiotransparent applicator attached to the
waveguide for recei~ing the electromagnetic energy;
providing a movable deflector within the applicator;
deflecting the electromagnetic energy propagated into the
applicator outwardly from the deflector toward the metal
surfaces having rust and scale buildup thereon for a sufficient
period of time to enable the electromagnetic energy to heat the
film of water trappecl under the scale and rust, causing the
water to expand and dislodge the scale and rust from the metal
surfaces; and
varying the position of the deflector to change the
broadcast location for the electromagnetic energy to enable the
: electromagnetic energy to sweep all of the metal surfaces to
remove rust and scale therefrom.
In accordance with another broad aspect of the
invention there is provided a method of removing paraffin from
sur~aces having a paraffin buildup thereon resultiny from
expo~ure to a paraffinic oil, comprising the steps of:
generating electromagnetic eneryy in the frequency range
of about 300 megahertz to about 300 gigahertz;
transmitting the electromagnetic energy toward the
paraffinic oil through a waveguide;
providing a radiotransparent applicator in communication
with the waveguide to receive the electromagnetic energy
transmitted through the waveguide;
` deflecting the electromagnetic energy toward the surfaces
containing the paraffin ~uildup to heat and remove the paraffin
therefrom; and
homogenizing the removed paraffin with other hydrocarb~ns
present in the paraffinic oil as a result of exposure to the
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alectromagnetic energy to cause the paraffin to remaln in
: solution in the oll.
In accordance with another broad aspect of the
invention there is provided a method of heating a hydrocarbon
fluid to provide a lower pour point, comprising the steps of,
generating electromagnetic energy ln the frequency range
of about 300 megahertz to about 300 gigaher~z;
transmitting the electromagnetic energy to the hydrocarbon
fluid through a waveguide;
providing a radiotransparent applicator in communication
with the waveguide to receive the electromagnetic energy
~; transmi~ted through the waveguide;
deflecting the electromagnetic energy into the hydrocarbon
: fluid by a deflector positioned within the applicator to heat
the hydrocarbon fluid;
controlling the time during which the electromagnetic
energy i5 applied to the hydrocarbon fluid; and
varying ~he portion of the hydrocarbon fluid over which
the electromagnetic energy is applied to effectively heat the
entire volume of the hydrocarbon fluid while controlling its
temperature;
ceasing the transmission of electromagnetic energy to the
hydrocarbon fluid; and
allowing the hydrocarbon fluid to return to its original
temperature, whereby the hydrocarbon fluid has a lower pour
point ~han it initially had at that temperature.
In accordance with another broad aspect of the
invention there is provided a method of recovering a
hydrocarbon fraation having a lower boiling point than water
from a hydrocarbon fluid which includes water, comprising the
steps of,
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72385-1
yenerating electromagnetic energy in the frequency range
of about 300 megahertz to about 300 gigahertz;
transmitting the electromagnetic energy to the hydrocarbon
fluid through a waveguide;
providing a radiotransparent applicator in
communication with the waveguide to receive the electromagnetic
energy transmitted through the waveguide;
deflecting the electromagnetic energy into the hydrocarbon
fluid by a deflector positioned within the applicator to heat
the hydrocarbon fluid;
controlliny the time during which the electromagnetic
energy is applied to the hydrocarbon fluid; and
varying the portion of the hydrocar~on fluid over which
the electromagnetic energy is applied ~o effectively heat the
entire volume of the hydrocarbon fluid while controlling the
temperature;
continuin~ the heating of the hydrocarbon fluid with
electromagnetic energy until the hydrocarbon fraction has been
boiled of~ from the water as a vapor; and
condensing the resulting hydrocarbon fraction after
xemoval from the water.
In accordance with another broad aspect of the
invention there is provided a method of reducing the viscosity
of oil flowing in an oil pipeline and removing paraffin from
the walls of the pipeline, comprising the step~ o~:
coupling a wavecJuide to the pipeline;
~ providing a radiotransparent sealing member between the
:~ waveguide and pipeline which is transparent to electromagnetic
energy but impermeable to the oil in the pipeline~
generating electromagnetic energy in the frequency range
of about 300 megahertz to about 300 gigahert~;
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72385-1
transmitting the electromagnetic energy into the pipeline
through the waveguide;
heating the oil in the pipeline and the paraffin on the
sidewalls of the pipeline as a result of exposure to the
electromagnetic energy; and
homogenizing the heated paraffin wi~h other hydrocarbons
in the oil as a result of exposure to the electromagnetic
energy to cause the paraf~in to remain in solution in the oil.
In accordance with another broad aspect o~ the
invention there is provided a method of recovering hydrocarbon
fractions from a geological substrate, comprising the steps of,
providing a borehole for access to a payzone o~
hydrocarbon ma~erial;
generating electromagnetic energy in the frequency range
; of from about 300 megahertz to about 300 gigahertz;
propagating the electromagnetic energy through a waveguide
position in the borehole;
providing a radiotransparent applicator in communlcation
with the waveguide to receive the electromagnetic energy;
providiny a deflec~or within the radiotransparent
applicator for deflecting the electromagnetic energy from the
radiotransparent application into ~he payzone;
varying the position of the deflector within the
radiotransparent applicator to concentrate the electromagnetic
energy on a particular portion of the payzone; and
injecting a pressurized gas into the borehole to
~acilitate movement of the resulting fractions toward the
surfa~e for recovery.
In accordance with another broad aspect of the
~ 30 invention there is provided a method of recovering hydrocarbon
: fluid from hydrocarbon material present in a geological
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.substrate, including the s~eps of:
providiny a bor~hole which ex~ends into the earth to a
position adjacent a payzone of hydrocarbon material;
generating electromagnetic eneray in the frequency range
of from about 300 megahertz to about 300 gigahertz;
propagating the electromagnetic energy through a coaxial
waveguide having hollow inner and outer conductors po~itioned
in the borehole;
providing a radiotransparent appllcator in communication
with the waveguide to receive the electromagnetic energy;
radiating the electromagnetic energy from the
radiotransparent applicator into the payzone; and
pumping ~he resulting hydroearbon fluid whose fluency has
been increased by application of the electromagnetic energy to
the surface through the inner conductox of the coaxial
waveguide to cool the inner conductor and supply further heat
to the resulting hydrocarbon fluld.
In accordance with another broad aspect of the
invention there is provided a method of automatically
insulating a ~torage vessel by using a portion of ~he
hydrocarbon fluid present in the ves~el to serve as an
insulating layer in response to cold temperature condltions,
; comprising the steps of:
generating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 gigahertz~
propagating the electromagnetic energy through a
waveguide;
providing a radiotran~parent applicator in commun~cation
with ~he wavegulde ~o receive the electromagnetic energy;
providing a perforated metal shleld concentrlc with the
sidewalls of the vessel and spaced therefrom a distance equal
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to the desired thickness of the insulating layer, the
perforation in the metal shield being dimensioned to allow the
hydrocarbon fluid to flow from one side to the other of the
metal shield during warm and mild temperature conditions when
.~ the hydrocarbon fluid has a low viscosity while at the same
time being smaller than the amplitude of the electrlc field;
deflecting the electromagnetic energy into the hydrocarbon
fluid to heat the hydrocarbon fluid present within the
perimeter of the metal shield while the metal shield reflects
the electromagnetic energy to prevent heating of the layer of
hydrocarbon fluid between the metal shield and the sidewalls,
thereby enabling this layer to remain solidified to provide an
automatic insulating layer for the vessel during cold
temperature conditions.
In accordance with another broad aspect of the
invention there is provided a method of separating fractions
from hydrocarbon material such as coal, lignite, peak, oil
shale, and tar/oil sands ln a geological substrate, comprising
the steps of:
~0 providing a borehole which extends into the earth to a
position adjacent a payzone of hydrocarbon material;
generating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 gigahertz;
~ transmitting electromagnetic energy into the borehole
: through a waveguide;
`~ deflecting the electromagnetic energy into the
hydrocarbon material;
` exposing the hydrocarbon material to the ele~tromagnetic
energy for a sufficient period of time to separate the
fractions present in the hydrocarbon material;
first separating water from the hydrocarbon material;
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72385-1
next separating sulfur in the form of gas from ~he
hydrocarbon material; and
then separating any condensible and noncondensible gases;
and
finally separating oil from the hydrocarbon material.
In accordance with another broad aspect of the
invention there is provided a method of reconstituting drilling
fluids removed from the boreholes of oil wells, comprising the
steps of~
removiny the drilling fluids from the borehole;
generatlng electromagnetic energy in the frequency range
of from about 300 megahertz ~o abou~ 300 gigahertz;
transmitting the electromagnetic energy to thq drilling
fluids through a waveguide;
providing a radiotransparent applicator in communication
with the waveguide to receive the electromagnetic energy
transmitted through the waveguide; and
de1ecting the electromagnekic energy into the drilling
fluld~ to heat the drllllng flulds to a sufficlent temperature
to remove the excess liquids therefrom leaving a slurry or
residue.
In accordance with another broad aspect of the
invention there is provided a method for lncreaslng the yleld
of hydrogen fro~ coal, comprising the step~ of:
: generating electromagnetic eneryy in the frequency range
:; of from about 300 meyahertz to about 300 gigahert7.;
providing a waveguide for propagation of the
electromagnetic energy toward the coal;
providing a radlotransparent applieator attached to the
30 waveyuide for receiving the electromagnetic energy;
providing a movable deflector with the applicator;
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723g5-1
deflectin~ the electromagnetic energy into the coal to
heat the same;
providing a plurality of sensors for detecting the
temperature at various points within the coal;
varying the position of the deflector to change the
broadcast location for deflecting the electromagnetic energy
into the coal in accordance with the temperatures sensed by the
sensors to provide suhstantially uniform heating of the coal;
and
removing ~he hydrogen gas emanating from the coal as a
result of the heating of the same with electromagnetic energy.
In accordance with another broad aspect of the
invention there is provided a method for desulfurizing
hydrocarbon material, comprising the steps of:
generating electromagnetic energy in the frequency range
of from about 300 megahertz to about 300 ~iyahertz;
providing a waveguide for propagation o~ the
electromagne-tic energy toward the hydrocarbon material;
providing a radiotransparent applicator attached to the
waveguide for receiving the electromagnetic energy;
providing a movable deflector within the applicator;
deflectin0 the electromagnetic energy into the hydrocarbon
material to heat the same;
sensing the temperature of the hydxocarbon material at
various locations;
varying the position of the deflector to change the
broadcast location for defleeting the electromagnetic energy
into the hydro~arbon material in accordanee with the
temperature sensed at the various locations to provide a
: 30 substantially uniform heating of the hydrocarbon ~aterial; and
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72385-1
removing the sulfur yas emanating from the hydrocarbon
material as a result of the heating of the same with
electromagnetic ener~y.
In accordance with another broad aspect of the
invention ~here is provided an apparatus for sequentially
recovering fractions from hydrocarbon material housed within a
container~ comprising.
radio frequency generator means for positioning proximate
to the container for generating electromagnetic energy in the
frequency range of from about 300 megahertz to about 300
gigahertz;
a radiotransparent applicator for positioning in the
container;
waveguide means for coupling said radio frequency
generator means to said applicator;
deflector means positioned in said applicator for
deflecting the electromagnetlc eneryy into the hydrocarbon
ma~erial wi~hln the container;
temperature sensing means arranged for detecting the
temperature of the hydrocarbon material at various levels
within the container; and
means for moving said deflector means within said
radiotransparent applicator in accordance with the temperature
ssnsed by said sensing means to change the broadcast location
of said de~lector means to control the temperature within the
hydrocarbon material at various levels to facilitate the
recovery of fractions from the hydrocarbon material.
In accordance with another broad aspect of the
invention there is provided apparatus for removlng high
viscosity hydrocarbon fluid from a barge, tanker and similar
vesselæ by increasing the fluency of the hydrocarbon fluid,
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72385-1
comprising:
radio frequency generator means for generating
electromagnetic energy in the frequency range of from about 300
megahertz to about 300 gigahertz;
waveguide means having one end coupled to said radio
frequency generator means to receive electromagnetic energy and
a remote end;
radiotransparent applicator means in the shape of a tube
for receiving electromagnetie energy from said waveguide means,
said radiotransparent applicator having one end a~fixed to said
remote end of said waveguide means and a closed end;
deflector means positioned in said radiotransparent
applicator means for deflecting the electromagnetic energy into
the hydrocarbon fluid;
means for moving said deflector means within said
radiotransparent applicator means; and
sealing means for coupling said waveguide means to a
manhole in the vessel to prevent the loss of electromagnetic
energy when said waveguide means and said radiotransparen~
applieator means are positioned within the vessel and said
radio frequency generator means is energized and to seal
against the entrance and exit of gases and liquids.
In accordance with another broad aspect of the
invention there is provided apparatus $or automatically
insulating a storage container when required by changes in
te~perature eonditions by utilizing a portion of the
: hydrocarbon fluid presen~ within the container to provide the
insulation, comprising:
perforated metal shield means concentricaIly arranged
within the storage container and spaced inwardly from the
sidewalls of the storage container a predetermined distance
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corresponding to the desired thickness of the insula-ting layer;
means for maintaining the position of said perforated
metal shield within the storage container;
radio fre~uency generator means for generating
electromagnetic energy in the frequency range of from ahout 800
megahertz to about 300 gigahertz;
waveguide means for transmitting the electromagnetic
energy to the s~orage container;
radiotransparent applicator means positioned within the
storage container for receiving electromagnetic energy from
said waveguide means;
deflector means positioned within said radiotran~parent
applicator to deflect the electromagnetic energy received by
said radiotransparent applicator means into the hydrocarbon
fluid;
said perforations in said metal shield being dimensioned
ko allow the hydrocarbon fluid between said metal shield and
the sidewalls of the storaye container to circulate
therethrough and mix with the hydrocarbon fluid interior o~
said perforated metal shield when the vi~cosity of the
hydrocarbon fluid is low during warm and mild temperature
conditions and preventing such circulation when the viscosity
of the hydrocarbon fluid increases during cold temperature
conditions, said perforations in said me~al shield having a
dimension smaller than the amplitude of the electric fleld so
that said metal shield wlll reflect the electromagnetic energy
inwardly preventing it from heating the layer of hydrocarbon
fluid between said metal shield and the sidewalls of the
storage container to allow the same to solidify and form an
insulating layer during cold temperature conditions.
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In accordance with another broad aspect of the
invention there is provided an apparatus for recovering
frac~ions from a payzone of hydrocarbon material in a
geological subs~rate by u~ing a borehole, comprising:
radio frequency generator means for generating
electromagnetic energy in the frequency range of about 300
megahertz to about 300 gigahertz;
: a waveguide coupled to said radio frequency generator
means for receiving electromagnetic energy;
a radiotransparent applicator having one end affixed to
said waveguide and a remote closed end arranged within the
borehole in the geological substrate;
deflector means positioned in said radio transparent
; applicator to deflect the electromagnetic energy;
moving means coupled to said deflector means for ralsing
and lowering the same in said radiotransparent applicator to
deflect khe electromagnetic energy in~o the payzone;
: temperature sensing means arranged proxlmate to said
deflector means to provlde temperature indications; and
controller means coupled to said radio frequency generator
: means, said controller means controlling said radio frequency
generator means and moving said deflector means in response to
" temperature indications from said temperature sensing means.
In accordan~e with another broad aspect of the
: invention there is provided an apparatus for reducing the
viscosity of oil flowing in a pipeline and removing paraffin
from the walls of the pipeline, comprising:
waveguide means for coupling to one end of the pipeline;
radiotransparent sealing means positioned be~ween said
waveguide means and the end of khe pipeline, said
radiotransparen~ sealing means being transparent to
8n
72385-1
electromaynetic energy buk impermeable to the oil in the
pipeline;
radio frequency generating means for generating
electromagnetic energy in the fxequency range of about 300
megaher~z to about 300 gigahertz;
said radio frequency generating means being coupled to
said waveguide to transmit electromagnetic energy into the
pipeline through said radiotransparent sealing means to heat
the oil in the pipellne and the paraffin on the sidewalls of
the pipeline so tha~ the paraffin ho~ogenizes with the other
hydrocaxbons in the oil and remalns in solution in the oil.
In accordance with another broad aspect of the
invention there is provided an apparatus for desulfurizing
hydrocarbon material including sulfur, comprising:
radio frequency generator means for generating
electromagnetic energy in khe frequency range o~ ~rom about 300
megahertz to about 300 gigahertz;
wavegulde means coupled to said radio frequency generator
means for propagation of the e}ectromagnetlc eneryy toward the
hydrocarbon material;
: radio~ransparent applicator means coupled to said
waveguide means for receiving the eleatromagnetic eneryy
therefrom;
energy deflector means positioned in said radlotransparent
applicator for deflecting the electromagnetic energy into the
hydrocarbon material;
temperature sensing means for sensing the temperature at
various locations in the hydrocarbon material; and
means ~or moviny said energy deflector means in said
radiotxansparent applicator means in response to the
73~
72385-1
temperatures sensed by said temperature sensing means to
control the temperature of the hydrocarbon material and provide
a substantially uniform heating of the hydrocarbon material.
Other objects, aspects and advantages of the present
invention will be apparent from the detailecl description
considered in conjunction with the drawings, as follows:
BRIEF DE5CRIPTION OF THE DRAWINGS
FIGURE 1 is a side eleva~ional view~ with parts
broken awayr of an apparatus in accordance with the present
invention for providing clean, separated oil from hydrocarbon
fluids stored in vessels;
FIGURE 2 is an enlarged .side elevational view of one
form of energy deflector which may be used in the apparatus of
Fig. 1 or in subsurface applications;
FIGURE 3 is an enlarged side elevational view of
another embodiment of an energy deflector which may be used in
the apparatus of Fig. 1 or in subsurface applications;
FIGURE 4 is an enlarged side elevational view of
another embodiment of an energy deflector which may be used in
the apparatus of Fig. 1 or in subsurface applications;
FIGURE 5 ls an enlarged side elevational view of
another embodiment of an energy deflector which may be used in
the apparatus of Fig. 1 or in subsurface application;
FIGURE 6 is an enlarged side elevational view of
another embodiment of an energy deflector which may be used in
the apparatus of Fig. 1 or in subsurface applications;
FIGURE 7 is a perspective view of an apparatus in
accordance with the present invention for increasing the
8p
735
fluency of high viscosity oi.l and sludge found in the hold
of a vessel, here illustrated as a barge;
FIGURE 8 is a side elevational view of an appara-
tus in accordance with the present invention for increasing
the fluency of oil in a pipeline;
FIGURE 9 is a side elevational view, with parts
broken away, oE an apparatus in accordance with the present
invention for in situ recovery of hydrocarbons from hydro-
carbon material;
FIGURE 10 is a schematic and side elevationalview,
with parts broken away, of an apparatus in accordance with
the present invention for in situ recovery of fractions from
oil shale, coal, peat, lignite and tar sands, showing the
separation and scrubbing of the fractions;
FIGURE 11 is an enlarged view of an applicator and
deflector in accordance with the present invention for ln
situ recovery of fractions from hydrocarbon material;
FIGURE 12 is an enlarged view of a coaxial wave-
guide applicator, deflector and pump in accordance with the
present invention for in situ recovery of fractions from hydro-
carbon material; and
FIGURE 13 is a side elevational view, with parts
broken away, of a storage vessel including metal shields
in accordance with the present invention for providing an
insulating layer of hydrocarbon fluid.
DETAILED DESCRIPTION
In the course of using electromagnetic energy to
heat hydrocarbon materials to increase their fluency, appli-
cant has discovered that with continued exposure to electro-
magnetic energy the fractions present within the hydrocarbon
_q _
L2,~73~
material sequentially separate ou-t at different points in
time providing purified or clean oil. Therefore, water,
acids, sulfur, chlorides, sediment and metals can be
readily separated and easily removed from the hydrocarbon
materials. This separation occurs as a result of the vary-
ing ability of these materlals to absorb electromagnetic
energy at different frequencies due to the differences in
the dielectric constants and loss tangents and therefore
the lossiness of the materials. Advantageously, by con-
trolling the;period of time during which the hydrocarbon
material is exposed to electromagnetic energy and/or vary-
ing the frequency and field strength thereof, the desired
fraction or fractions can be most efficiently separated
from the residual hydrocarbon material.
The residual products which remain after removal
of oil, gases, sulfur and condensates from coal with electro-
magnetic energy are coke and ash. The yield of hydrocarbon
resulting from the present invention has been found to be
much greater than that produced by conventional heating
techniques. The coke may be removed at a later date for
use in metal processing or for the production of briquettes.
The quality of the char resulting from heating coal and petro-
leum coke in accordance with the present invention is generally
far superior to that which is produced with conventional methods.
Further, it has been found that the temperature of
a hydrocarbon fluid having a kinematic viccosity in the
range of about 20 seconds Saybolt Universal to about 500,000
seconds Saybolt Universal at 100F can be more effectively
controlled to maximize production, minimize energy costs and
prolong the life of the magnetron filament by controlling
the broadcast location of the electromagnetic energy. I-t
has also been found that scale, rust and paraffin can be
~ 3 S
removed from metal surfaces in storage vessels by employ-
ing electromagnetic energy in accordance with the present
invention. It also has been discovered that the pour
point of the oil which results from exposing the hydro-
carbon fluid to electromagnetic energy in accordance with
the present invention is lower than that produced by con
ventional heating techniques. Advantageously, the present
invention may also be utilized to automatically create a
layer of insulation for a storage vessel from the hydro-
carbom fluid present therein, as required by ambient tem-
perature conditions.
Referring to Fig. 1, an apparatus in accordance
with the present invention is generally illustrated at 14
for use with a vessel or open or closed top oil storage
tank 15 or mud pit. The hydrocarbon fluid, such as oil,
stored in the tank 15 often contains water, sulfur, solids
and other undesired consitutents or contaminates, including
bacterial and algae, as well as scale and rust, all of which
may be considered as basic sediment. Moreover, during
storage, the contamination and viscosity of the oil will
often increase to the poin-t where the LACT (Lease Acquisi-
tion Custody Transfer) measurement is often too great for
pipeline acceptance. Advantageously, the apparatus 14 not
only heats the oil to ~crease its viscosity and increase
its fluency, but also separates water, sulfur and basic
sedimen-t from the oil in the tank lS, resulting in clean
oil. The exiting gases, including suflur, may be collected
via a collection line and holding tank (not shown) which are
in communication with the top of the tank 15.
The apparatus 14 includes a radio frequency (RF)
generator 16 which includes a magnetron 17 or klystron, or
other similar device, such as a solid state oscillator as
disclosed in the aforementioned reissue patent, which is
capable of generating radio waves in the frequency range
of from about 300 megahertz to about 300 gigahertz and
generally utilizing from lKW to lMW or more of continuous
f~ 7~5
wave power. However, it should be understood that a
plurality of magnetrons 17 or oscillators, or a klystron
may be used to generate a plurality of heating frequencies
which are far enough apart to prevent interference and
which may have greater absorptivity to certain fractions
which it is desired to remove. In this regard, the os-
cillator may be further modified or another oscillator may
be provided to generate a frequency outside of this range
for use with the aforementioned frequencies in accordance
with the lossiness of the fractions to be removed. The
magnetron 17 is mechanically coupled to an applicator 18
which is transparent to radio waves in the aforementioned
frequency range. Advantageously, the applicator 18 is in
the shape of an elongated tube with an open upper end 19
and a closed bottom end 20. The applicator 18 is prefer-
ably constructed from resin with glass fibers, fused alumina,
silicon nitride or similar radiotransparent materials so
that it is permeable to RF waves in the desired frequency
range but impermeable to liquids and gases. The applicator
18 is attached, e.g., by means of glass cloth and epoxy
resin, to a tubular metal waveguide 21, constructed of alum-
inum or nickel and iron, which passes through metal tank
cover 22. The tank cover 22 is bolted and grounded to the
tank 15 by a plurality of nuts and bolts indicated at 24.
A metal transition member 26, which includes a
flanged end 28, is bolted to one end of 90~ metal elbow
30 by bolts and nuts 32. The tubular end 33 of the trans-
ition member 26 is attached to the tubular waveguide 21,
e.g., by welding, threading or flanging, as desired. The
other end 34 of the 90 elbow 30 is bolted to one end of
rectangular metal waveguide portion 36, which may be formed of
6061-T6 aluminum,by nuts and bolts 38.
~26~L~73~
The other end of the rectangular waveguide 36 is
coupled to WR x coaxial transition member 40 with nuts and
bolts 42. Flexible coaxial member 44, which may have its
inner and outer conductors constructed of copper with poly~
ethylene covering, is fitted with flanged ends 46 and ~8
which advantageously have internal gas barriers to allow
the flexible coaxial member 44 to be charged with an inert
gas refrigerant, such as Freon, to increase its power carry-
ing capacity while preventing the flow of any gases emanating
from the hydrocarbon fluid back into the RF generator 16,
which may result from a rupture or leakage in the applicator
18. Flanged end 46 is coupled to the WR x coaxial transition
member 4~ with bolts and nuts 50 and flanged end 48 is
coupled to coaxial x WR transition member 52 with bolts
and nuts 54. The flanged end of the coaxial x WR trans-
ition member ~2 is coupled to the RF generator 16 through
a rectangular extension portion 56 which receives the elec-
tromagnetic energy generated by the magnetron 17.
A controller 58 controls the energization of the
RF generator 16 and receives signals from a plurality of
temperature sensors 60 A-E arranged within the tank 15.
The controller 58 may be coupled to the sensors 60 A-E by
interconnection wires or by fiberoptic transmission lines
62, as desired. The sensors 60 A-E are advantageously ver-
tically spaced at predetermined intervals or locations with-
in the tank 15.
A generally conically shaped energy deflector 64is arranged within the applicator 18 for upward and downward
movement to control the broadcast locations for the electro-
magnetic energy propagated through the applicator 18. This
upward and downward movement is provided by a motor 66 which
d~ives a pulley 68 causing it to wind or unwind cable 70
attached to the energy deflector 64, thereby controlling
-13
'73~
the vertical broadcast location of the deflector 64 within
the tank 15. However, as desired, a separate frequency
may be transmitted through the waveguide 36 to activate
the motor 66. Preferbly, the energy deflector 64 is ini-
tially located near the bottom of the applicator 14, i.e.,
at the bottom of tank 15, and moved gradually upward since
the lighter oil will tend to rise to the top and the heavier
water will sink to the bottom of the tank 15.
Advantageously, by broadcasting the energy in this
manner, the magnetron 17 may run continuously at full power
to operate at the greatest efficiency, the temperature at
various layers within the hydrocarbon fluid can be effect-
ively controlled, so that the production of oil is maximized,
and the life of the anode or filament of the magnetron 17
is prolonged.
The motor 66 is connec-ted to a power source (not
shown) through controller 58 by line 72. The controller 58
activates the motor 66 to move the deflector 64 thereby
changing the broadcast location for the electromagnetic
energy in response to the temperatures sensed by sensors
60 A-E. Further, the frequency and period of application
of the electromagnetic energy is controlled by the con-
troller 58 which may be preset or programmed for continuous
or intermittent upward and downward cycling to achieve homo
geneous heating of the hydrocarbon fluid or localized heat-
ing, as desired, to achieve the highest yield or best pro-
duction of oil at minimum energy cost. The broadcast location
of the energy deflector 64 may be preset to provide predetermined
controlled continuous or intermittent sweeping of the electro-
magnetic energy through the hydrocarbon fluid by employing a
conventionl timer and limit stops for the motor 66.
-14-
~ 3~5
Advantageously, valves 74 A-D may be located in
the vertical wall of the tank 15 to draw off the oil after
the treatment with electromagnetic energy has been completed.
After heating with elec~roma~netic energy in accordance with
the present lnvention, the results are illustrated in Fig.
1. Near the bottom of the tank 15 is a layer which is es-
sentially basic sediment and water, designa-ted as 76. Above
the bottom layer 76 is an intermediate layer designated 78
which is a mixture of mostly oi] with some basic sediment
and water Finally, above the layer 78 is a top layer desig-
nated 80 which represents the resulting oil which has been
cleansed and is free of basic sediment and water. Located in
the sidewall of the tank 15 near its bottom is an access hatch
73 for removing the resulting basic sediment, which may in-
clude !'drilling mud" solids. Advantageously, any bacteria and
algae present in the hydrocarbon fluid are disintegrated by
the RF waves, with their remains formin~ part of the basic
;~ sediment.
; To further aid circulation and cleansing of the layer
of oil 80, a conventional conduction heater, such as a gun
barrel heater 75 may extend into the tank 15. This heater 75
which may be gas or oil driven, circulates hot gases through
piping 77 to provide a low cost source of BTUs to further heat
the oil once the water and basic sediment has been separated
from the oil and the oil is sufficiently liquified or fluid for
convection currents to flow. (Steam coils may be used as an
al-ternative, as desired.) These convection currents further
aid in reducing the viscosity of the oil and removing fine sedi-
ment. A spark arrester 79 is provided in the piping 77 to
eliminate any sparks in the exiting gases. Further, the
cleansed oil may be passed through a Teflon filter to remove
any remaining fine sediment therefrom as a cake.
Oil which is extracted from well bores often contains
a considerable amount of basic sediment and water, and pos-
sibly a high concentration of paraffin as well. These
undesirable cons~ituents present a major problem for the oil
industry because the oil must meet certain minimum API speci-
fications, such as compliance with LACT measurements, before
it can be transferred to a pipelin~ for refining or distribu-
tion. Heater treaters, separators, expensive chemicals an~
filters have been used to meet these minimum specifications
with a limited degree of success.
By utilizing the method and apparatus of the present
invention, clean oil is readily and easily separated from
basic sediment and water. This is ac~omplished by heating
the hydrocarbon fluid in the tank 15 with electromagnetic
energy which causes the water molecules which are normally
encapsulated within the oil to expand rupturing the encap-
sulated oil film. It is difficult to heat the encapsulated
water by conventional conduction or convection ~echniques
because the oil functions as an insulator. ~Iowever, such
heatiny can be readily accomplished with radio frequency
waves because water has a greater dielectric constant and
greater loss tangent than oil, which results in a high loss-
iness, thereby allowing it to absorb significantly more energy
than the oil in less time resulting in rapid expansion of
the volume of the water molecules within the oil film, causing
the oil film to rupture. The water molecules then combine
into a heavier than oil mass which sinks to the bottom of the
tank, carrying most of the sediment present in the oil with
it. However, to further facilitate removal of the basic
~ediment, particularly fines, brine or salt water may be
spread across the surface of the top layer of oil 80 after
the viscosity of the oil 80 has been lowered, through heat-
ing with electromagnetic energy in accordance with the present
invention. The heavier salt water will rapidly gravitate
through the layer 80 of oil toward the bottom of the tank
15, carrying the fine sediment with it.
Layers 76l 78 and 80 have resulted from treating
hydrocarbon fluid containing oil, basic sediment and water
stored in tank 15, by sweeping the fluid with electromagnetic
735;
energy in accordance with the apparatus in Fig. 1 having a
power output of 50 KW for approximately 4 hours. However,
it should be understood that the power output and time of
exposure will vary with the volume of the tank 15, the con-
stituents or contaminates present in the hydrocarbon fluid,
and the length of time during which the hydrocarbon fluid
has been stored in the tank 15.
Since hydrocarbons, sulfurs, chlorides, water
(fresh or saline~, and sediment and metals remain passive,
reflect or absorb electromagnetic energy at different rates,
exposure of the hydrocarbon fluid to electromagnetic energy
in accordance with the present invention will separate the
aforementioned constituents from the original fluid in
generally the reverse order of the constituents listed abo~e.
Further, acids and condensible and non-condensible gases are
also separated at various stages during the electromagnetic
energy heating process. For Bayol the optimum frequencies
for separation according to the lossiness of the oil in des-
cending order are 10 GHz, 100 Hz and 3 GHz; for Diala Oil the
optimum frequencies for separation in descending order are
25 GHz, 10 GHz, 300 MHz, 3 GHz and 100 MHz. For water, both
temperature and the frequency are significant for absorption
of RF energy. The opti~um frequencies, loss tangents and
boiling points for the various fractions present in the hydro-
carbon material which it is desired to recover can be obtained
from Von ~ippel, TABLES OF DIELECTRIC MATERIALS, (1954) pub-
lished by John Wiley & Sons, Inc., and ASHRAE HANDBOO~ OF
FUNDAMEN~rALS, (1981), published by the American Society of
Heating, Refrigerating and Air Conditioning Engineers, Inc.
Referring to Fig. 2, the applicator 18 and energy
deflector 64 are shown enlarged relative to that illustrated
in Fig. 1. The deflector 64 is suspended within the appli-
'~Z~i~735cator by the dielectric cable 70 which is constructed of
glass fibers or other similar radiotransparent materials
which are strong, heat resistant and have a very low di-
electric constant and loss tangent. The height of the energy
deflector 64 will determine the angle of deflection of the
electromagnetic energy.
Referring to Fig. 3, an alternative embodiment
for the deflector ~4 shown in Fig. 1 is illustrated as 82.
The deflector 82 has a greater angle of deflection (lesser
included angle) than the deflector 64 to cause the de-
flected waves to propagate from the applicatox 18 in a
slightly downward dixec-tion below a horizontal plane through
the deflector 82. This embodiment enables the radio fre-
quency to penetrate into payzones which may be positioned
below the end of a well bore, when the method and apparatus
is utilized for ln situ heating in a geological substrate.
The energy~eflector 82 is suspended by a fiberoptic
cable 84 which not only facilitates movement of the RF de-
flector 82, but also provides temperature readings. In
this respect, the individual fiberoptic strands 83 of the
fiberoptic cable 84 are oriented to detect conditions at
various locations in a vessel or borehole. The information
transmitted to the remote ends of the fiberoptic strands 83 can
be converted into a digital readout with an analog to digital
converter for recording and/or controlling power output
levels as well as for positioning the deflector 82. For
example, it may be desired to provide a vertical sweep
pattern of the RF energy in response to the temperature
gradients sensed by the fiberoptic strands 83. Advan-
tageously, the frequency ~or use with the fiberoptic strands
83 is selected to be sufficiently different from the fre-
quency of the RF generator 1~ to prevent interference or
cancellation.
Referring to Fi~. 4, the radiotransparent applica-
a ~
for downhole applications where the high temperatures en-
countered would be detrimental to fiberglass. Advantage-
ously, the waveguide 21 may be an alloy of 42~ nickel with
the remainder being iron and the applicator 18 may be formed
from 995 alumina metallized with molydenum manganese or
from silicon nitride. The brazing material 86 which may
be, e.g., 60% silver, 30% copper and 10~ tin,is applied be-
tween the applicator 18 and the waveguide 210 Arranged with-
in the applicator 18 is another embodiment of an energy de-
flector designated 88 whi¢h is constructed of pyroceram or
other similar dielectric material with a helical or spiral
band of reflective material 90, such as stainless steel, which
is wound around the ceramic material of the conically shaped
deflector 88 from its base to its apex for the purpose of
broadcasting a wide beam of RF energy over a large vertical
layer in a wellbore or vessel in order to broadcast over a
greater volume of the hydrocarbon fluid with less concentrated
energy, in effect diffusing the electromagnetic energy to
provide an energy gradient. Advantageously, instead of pro
viding the aforementioned band of metal 90, a spiral portion
of the alumina or silicon nitride energy reflector 88 may be
sintered and metallized to provide the desired reflective
band by conventional vacuum deposition techniques.
It should be understood that other means may be
employed to raise and lower the deflector to accomplish the
sweeping function, including hydraulic, vacuum, air pressure
and refrigerant expansion lifting systems. Further, the wave-
guide coupling from the RF generator 16 may also be utilized
to send control signals from the controller to the motor or
other mechanism for raising and lowering the ~F deflector.
However, it should be understood that the frequency for such
--19--
3~i
control signals must be selected to be sufficiently differ-
ent from the frequency or frequencies selected for the
electromagnetic energy which heats the hydrocarbon fluid
to prevent interference or cancellation. Thus, the wave-
guide coupling can be utilized to carry signals having dif-
ferent bandwidths without having one frequency interfere
with another. For example, an oscillator may be coupled
to the waveguide to provide K band frequency for tempera-
ture sensing while C bank frequency is generated by the RF
generator 16 for heating the hydrocarbon fluid.
Referring to Fig. 5, another form of energy de-
flector is indicated at 91. This deflector 91 is essentially
a right angle triangle in cross section with a concave sur-
face 93 for focusing all of the deflected electromagnetic
energy in a particular direction to heat a predetermined
volume in a vessel or a particular payzone or coal seam in
subsurface applications.
Referring to Fig. 6, another form of energy de-
flector is indicated at 94. This deflector 94 includes in-
terconnected segments 95A-95D which provide one angle for
deflection of the electromagnetic energy when the deflector
is abutting the applicator 18, as shown in Fig. 6, and an-
other angle of deflection for the electromagnetic energy
when the cable 70 is pulled upwardly causing the segments
95~--95D to retract. However, it should be understood that
other means may be employed to change the angle of deflection
of the deflector 94, such as a remote controlled motor.
The disposal of drilling fluids known as "drilling
mud" has become a severe problem for the oil industry. ~d-
vantageously, the apparatus shown in Fig. 1, modified to
incorporate any of the energy deflectors illustrated in Figs.
2-6, may be utilized to reconstitute drilling mud for reuse
735
by application of radio frequency waves to remove the excess
liquids and leave a slurry of bentonite, barite salts, etc.
If desired, some of the chemical additives, as well as
water and oil, can be reclaimed in this manner from the mud
and well bore cuttings by removing substantially all of the
liquids. The removed water which is in the vapor or steam
phase may be compressed into high pressure steam suitable
for running a turbine to generate electricity.
Referring to Figure 7, apparatus in accordance
with the present invention, designated as 100, can be advan-
tageously employed to remove high viscosity hydrocarbon
fluid or sludge from vessels, such as oil tankers or barges
102. A mobile RF generator 104, which includes an oscillator,
klystron or magnetron 106, has attached thereto at its out-
put 110 a flexible coaxial waveguide 108 which may be formed
of copper. The other end 112 of the flexible coaxial wave-
guide 108 extends through a manhole cover sealing connection
114 position in a manhole 115 in the barge 102. The sealing
connection 114 is fluid tight to seal against the escape
of liquids and gases and also radio frequency tight to pre-
vent the escape of RF energy when the sealing connection 114
is positioned in the manho~e 115. Typical power supplied to
the RF generator 106 may be 480 V, 3 phase, 60 Hz at 100 amps.
The flexible waveguide 108 is affixed at its other end to a
tubular waveguide 116 which in turn is attached to a radio-
transparent applicator 118. Positioned within the applicator
118 is an energy deflector 120 which is capable of upward
and downward broadcast movement, as desired, and may be of
any one of the types disclosed in FigsO 2-6. A suitahle
mechanism for moving the energy deflector 120 upwardly and
downwardly, such as disclosed in Fig. 1, is employed. More-
over, it is advantageous to provide inert gas shielding for
~ 3
the flexible coaxial waveguide 10~ as disclosed with refer~
ence to Fig. 1.
The oil heated by RF waves may be removed from
the respective compartment of the barge 102 by a suction
pump 122 for storage in a tank (not shown). The pump 122
has a flexible hose 124 which is positioned within a second
manhole 126 in the same compartment for extraction of the
heated oil. For clarity, the pump 122 and hose 124 are
shown positioned in a manhole of another compartment, although
it should be understood that oil can be removed from the com-
partment being heated, as desired.
The arrows emanatin`g outwardly from the deflector
120 and the applicator 118 indicate a typical pattern for
the radio frequency waves. As the waves leave the radio-
transparent applicator 118 they are absorbed by the oil/
water mixture or penetrate slightly into the inner tank skin
of the sidewalls heating the oil trapped in the pores where
they are absorbed or reflected by the metal walls of the com-
partment until all of the RF energy is eventually converted
into heat in the hydrocarbon fluid. It should be understood
that although the present invention is illustrated in Fig.
7 for use with a barge it can be used with any type of ship,
vessel or enclosure.
Moreover, it has also been discovered that the
rust and scale buildup on the walls of oil tanker or barge
compartments can be removed, leaving bare metal walls, by
employing the method and apparatus of the present invention.
In this regard, when condensation results in oxidation of
the steel walls of a compartment, a film of water is trapped
under the resulting layer of rust or scale. By directing RF
energy to the walls, this water film is heated and expands
forming steam which causes the scale or rust layer to flake
,~ r ~
off in large sheets, similar to parchment with the corners
curled inward, until a clear base metal surface is left.
The removed rust or scale settles to the bottom of the
vessel as basic sediment. It should be understood tha-t
this technique can also be utilized to clean other metal
surfaces, including condenser tubes and the like.
Referring to Fig. ~, the present invention is
shown for use with an oil pipeline, specifically with a T
connection indicated at 130; the oil flow is as illustrated
by the solid arrows. However, it should be understood that
the present invention may be used with any pipeline including
an offshore oil rig. A waveguide 132 having a flanged end 134
is coupled to a mating flange 136 of the T connection 130.
A radiotransparent sealing disc 138, such as silicon nitride,
is sandwiched between the flanges 134 and 136 by bolts and
nuts 140. A metal RF shield ring 142 is arranged circum-
jacent the sealing disc 138 and sandwiched between the flanges
134 and 136. This RF shield ring 142 prevents the loss of
RF waves which are propagated along the waveguide 132 and
through the radiotransparent sealing disc 138 into the T
connection 130. The RF waves propagate through the oil in
the T connection 130 and through the oil in the pipeline 144.
Advantageously, such an arrangement heats the oil to de~
crease its viscosity, thereby requiring less pumping energy
to drive the oil through the pipeline 144, and further cleans
the walls of the T connection 130 and pipeline 144 of paraffin
causing the same to homogenize and remain in solution.
~`
Referring to Fig. 9, an apparatus in accordance
with the present invention, designated as 150, is shown posi-
tioned in an injection well 152 which is located adiacent at
least one producing well 154. The apparatus 150 includes
~ 73 ~
an RE generator 158 which is electrically coupled to a power
source (not shown) which supplies 3 phase, 460V, 60 Hz current
thereto. A magnetron 160 positioned within the RF generator
158 radiates microwave ener~y from an antenna or probe 162
into waveguide section 164 for propagation. A waveguide ex-
tension 166 has one end coupled to the waveguide section 164
with bolts and nuts 168 and its other end coupled to a wave-
guide to coaxial adapter 170 with bolts and nuts 172. A flexi-
ble coaxial waveguide 174, e.g., copper, is coupled at one end
to the adapter 170 through a gas harrier fitting 176. The
other end of the flexible waveguide 174 is coupled to a coaxial
to waveguide adapter 178 through a gas barrier member 180. A
transformation member 182 is coupled at one end to the adapter
178 with bolts and nuts 184. The other end of the transfor-
mation member 182 is coupled to a tubular waveguide 186, which
may be, e.g., at 915 MHz, 10 inches in diameter, for instance
by welding. A radiotransparent applicator 188 is attached to
the tubular waveguide 186 at 187, e.g., by brazing, for with-
standing the high temperatures encountered in downhole appli-
cations. The applicator 188 and energy deflector (not shown)
may include any of the types illustra~ed in Figs. 2-6 for broad-
casting RF waves. Further, the energy deflector will be coupled
to a raising and lowering meansr e.g., of the type illustrated
in Fig. 1.
The waveguide 186 is positioned within a casing 190
formed in the well 152. The well head 191 is capped by a sealing
gland 192 which effectively seals the waveguide 186 therein. A
plurality of thermocouples 194 are positioned in the well 152
between the casing 190 and the waveguide 186 and extend to a
location adjacent the bottom of the well 152. Leads 196 con-
nect the thermocouples 194 to a controller (not shown). The
leads 196 extend thr~ugh a packer seal 198 arranged between
the waveguide 186 and casing 190 near the bottom of the well
-24-
152. However, the packer seal 198 would not be used if it
is desired to produce the resulting oil, water and gases
through the annular space 199 between the casing 190 and
waveguide 186. Alternatively, in the absence of the packer
seal 198, the expansion of the oil, water and gases will drive
the same up through the annulus 199 until the constituents
in the immediate vicinity of the applicator 188 are removed.
Subsequently, the annulus 199 can be packed off with the packer
seal 198 and the hydrocarbons further heated to drive the re-
sulting oil, water and gas to the producing well 154. For
example, if the temperature of the oil is increased to 400F,
there is approximately a 40% increase in the volume of the
oil.
The RF energy emanating from the applicator 188, as
represented by the arrows, will heat the hydrocarbon material
in the geological substrate causing the release of water, gases,
and oil, with the hot oill water and gas flowing into the bottom
of the producing well 154 after the deflected RF energy melts
sufficiently through the solidified oil to establish a flow
path or communication path tothe producing well 154. The
volume increase in oil and water as a result of heating with
RF energy further aids in establishing such a flow path. The
pump set 200 of the producing well 154 pumps the oil, water
and gas mixture through a perforated gas pipe 202, centered
in the well casing 210 by centralizer 204 and production string
206 l~cated in well casing 210 to a takeout pipe 208. Specif-
ically, the pump set 200 moves a sucker rod 212 up and down
in the production string 206 to draw oil, water and gas through
the production string 206 into the take-out pipe 208 for trans-
mission to a desired oil treating facility, such as a storage
tank ~not shown). This storage tank may also include an ap-
paratus in accordance with the present invention, such as
the apparatus shown in Fig. 1, to provid~ separation of the
resulting constituents.
-25-
735
It should be understood that the injection well
152 illustrated in Fiy. 9 may be ~itted with supplementary
drive means, such as pressurized steam or carbon dioxide for
injection into the geological substrate through the annulus
199 formed between the well casing 190 and the waveguide 186
to aid in further heating the hydrocarbon material, but more
importantly to drive the heated water, gas and oil to the pro-
ducing well 154. Heating with electromagnetic energy will
normally cause the resulting products to move upwardly in
the annulus due to expansion of the oil, water and gas caused
by heating. This expansion will continue until the volumn
increasing ability of the hydrocarbons in the immediate vicin-
ity of the applicator 188 is xhausted. Thereafter, the annulus
199 can be packed or sealed off except for the supplementary
drive means, e.g., a steam pipe (not shown), which extends
therethrough. This approach aids in further reducing the
viscosity of the resulting hydrocarbonfluid by providing ex-
ternally heated steam in addition to the steam produced by
heat expansion of the oil and the connate water in the forrna-
tion. Carbon dioxide may be advantageously employed as the
driving medium in those environments where it is not desired
to introduce additionalw~ter (steam) which absorbs some of
the RF energy, reducing its efficiency in heating the hydro-
carbons.
~ eferring to Fig. 10, an apparatus in æcordance
with the present invention for in situ production of oil, gas
water and sulfur from oil shale, coal, peat, lignite or tar
sands by co-generation is illustrated generally at 220. Ad-
ditionally, this arrangement may be readily utilized to supply
additional electricity to local utilities. A well 222 is formed
in the earthextending through the overburden 224 and into the
bedding plane 226. The well 222 includes a cemented in steel
casing 230 and a waveguide 232 positioned within the casing 230
and coupled to a radiotransparent applicator 234 housing an
-26-
~ 7 3 ~
energy deflector 236, as described with refere~ce to Figs. 1-6.
Means to raise and lower the energy deflector 236, as described
with reference to Fig. 1 should be included, but the same has
beeneliminated for clarity. The waveguide 232 is affixed to
the well head 238 with a packing gland seal 2~0 and to a transi-
tion elbow 242 which includes a gas barrier. Coupled to the
remote end of the transition elbow 242 is a flexible coaxial
waveguide 244 which is coupled to an RF generator 246 which
includes a magnetion, klystron or solid state oscillator (not
shown~ for generating RF waves. Current is supplied to the
RF generator 246 from an electric generator 248 driven by a
turbine 250. High pressure steam is supplied to the turbine
250 from a boiler 252 which is preferably oil or gas fired, using
as fuel the fuel oil or gas received from the well 222~
Low pressure extraction steam which exits from
the turbine 250 is supplied to the annulus 254 between the
casing 230 and the waveguide 232 in the well 222 by a steam
line 251. The application of low pressure steam to the oil
shale, coal, peat, lignite or tar sands, in addition to the
RF energy serves to decrease the viscosity of the kerogen or
oil in the formation, causing the water, oil and gas to expand
and flow into the open hole sump 256, where it is forced up-
wardly under its own expansion and by the steam pressuxe to the
surface with the oiland gas entering exit oil line 258 and the
steam entering steam return line 260. The steam entering
the steam return line 260 can be demineralized in demineralizer
262, condensed in condensate tank 264 and resupplied to the
boiler 252, as desired.
The entering oil and gas is transmitted from the
oil line 258 to a conventional liqui.d/gas separator 260. The
-27-
7;~
separated oil is then transmitted to a storage tank for pipeline
transmission, as desired. The gas is treated by a conventional
cooler, saturator, absorber and desorber separa-ting system 262
to produce additional oil, naphthalerles, phenols, hydrogen,
and sulfur, as well as fuel oil for the boiler 252. In addition
to producing its own fuel oil and water, the co-generation
method and apparatus of Fig. 10 produces oil, gasoline, gas
condensates and sulfur which can be further stored, sold or
further used, as desired.
Referring to Fig. 11, a canted or angled energy de-
flector 280 is illustrated. The canted energy deflector 280
has a particular use in a well bore 282 in which the payzone
284 is inclined or offset relative to the well bore 282 so
that the radio frequency energy can be directed to the seam
or payzone 284. The deflector 280 is arranged at the bottom
of an applicator 286 which is coupled to a waveguide 288
with an E.I~A. flange 290. A corrosion resistant covering 292
advantageously surrounds the waveguide 288 and flange 290.
Extending downwardly from the casing 292 is a perforated
liner 294 which is transparent to RF waves and protects the
applicator 286.
Referring to Fig. 12, a coaxial waveguide arrange-
ment is illustrated at 300 for in situ production of oil
through a small diameter well bore 302. The well bore ~02
includes a casing 304 and a perforated radiotransparent liner
306 which extends downwardly therefrom. ~ coaxial waveguide
308 is positioned within the well bore 302 and coupled to a
radiotransparent applicator 310 with an E.~.A. flange 312.
A fiberglass or other corrosion resistant covering 314 sur-
rounds the waveguide 308 and the flange 312. The waveguide
308 includes a hollow central conductor 316 which is main-
tained in a spaced relationship from an outer conductor
317 with dielectric spacers 319, only one of which is shown.
The hollow central conductor 316 extends through the applicator
~ 2 ~ ~7 ~ S
310 for interconnection with a submersible pump 318 posi-tioned
within the liner 306. The interior of the central conductor
316 includes a fiberglass or polyethylene lining 320 to pro-
vide a production conduit through which oil is pumped to the
surface. The oil pumped therethrough also helps to cool the
inner conductor 316 by absorbing heat therefrom which in turn
helps to maintain a lower viscosity in the producing oil by
further heating it. Highly advantageous here is the cooling
effect of the oil on the central conductor 316 which prevents
overheating and dielectric breakdown of the dielectric spacers
319.
The pump 318 as shown in Fig. 12 is electrically
driven, receiving power through a power cable 322. However,
it should be understood that the pump 318 may be pneumatically
or hydraulically operated if it is desired to eliminate the
cable 322, e.g., in deep wells where too much friction may be
present. Further, if desired, the pump 318 may be actuated
by a magnetic field produced by RF waves which have a different
frequency than that of the RF waves used for heating. The
magnetic field can be used to rotate a magnetic drive mechanism
to pump oil to the surface. Advantageously, the coaxial wave-
guide 308 is smaller in diameter than the waveguide illustrated
in Fig. 11 to allow access to wells 302 having small diameter
bores.
Preferably, the pump 318 is supported by support wires
324 or rods coupled between eyelets 323 affixed to the pump 318
and eyelets 315 affixed to the flange 312. A dielectric oil
pipe 326 has one end coupled to the pump 318 with a flange 328
and passes through a central opening 330 in the energy deflector
332. A liquid tight seal, such as silcon nitride is applied there-
between. The other end of the oil pipe 326 is coupled to the
central conductor 316 with a dielectric coupling member 334.
The electric field resulting from the propagation
of the radio frequency waves through the waveguide 308 is atten-
uated along the central conductor 316. Normally, this attenuation
would tend to overheat the dielectric spacers 319, eventually
causing dielectric breakdown and arcing between the inner con-
ductor 316 and outer conductor 317, and ultimately a breakdown
of the coaxial waveguide 308. Advantageously, by having the oil
pass through the inner conductor 316, the oil acts as a coolant
to sufficiently cool the inner conductor 316 to eliminate the
problem of overheating the dielectric spacers 319.
The RF waves propagated through the waveguide 308
are radiated or broadcast outwardly from the portion of the cen-
tral conductor, designated 336, which functions as a 1/4 wave
monopole antenna. Any RF waves thattravel past the antenna 336
are deflected by the energy deflector 332.
Referring to Fig. 13, the present invention can be
used in a vessel containing hydrocarbon fluid to effectively
utilize a portion of the hydrocarbon fluid to provide an automatic
layer of insulation for the vessel, as needed. One apparatus
for accomplishing this function is generally illustrated in Fig.
13 as 350. It has been found that the resulting insulating value
is often greater than the R value of the usual mineral or cellulose
type insulators that are commonly used for this purpose. Conven-
tional practice with large oil storage or day tanks, and particularly
those used to store high viscosity No. 6 residual fuel oil (Bunker
C), is to fit the same with heating coils and heater sets to main-
tain the oil in liquid form for transportation to a pipeline. A
substantial amount of heat energy is lost through the metal walls
and roof of the tank unless it is insulated. Such insulation is
typically attached to the outer wall surfaces with stud welded
clips. The insulation is then cavered with a waterproof metallic
lagging. However, during this covering process moisture is trapped
between the tank walls and waterproof metallic lagging sothat
temperature variations between the enclosed space andanbient
-30
~ 3 5
causes wator vapor to condense on the tank walls. This leads
to oxidation of the wall surface and eventual rust out. I'hus,
an uninsulated tank will normally last for a much longer period
of time.
The method and apparatus of the present invention may
be employed to provide a specific thickness of immobile oil
in contact with and adjacent to the interior tank walls when
the ambient temperature or temperature conditions are low.
The R value of the insulation and the U factor will vary in
accordance with the k factor of the oil. For No. 6 oil, the
k factor is 0.070.
The tank 352 includes a perforated metal shield or
wire mesh 354 arranged concentric with the tank side walls 356
and spaced interiorly therefrom a predetermined distance. The
shield 354 is held at the required distance from the sidewall
356 by standoff brackets 358 which may be afflxed therebetween
by welding. S1milarly, perforated metal shields 355 and 357
may be positioned a predetermined distance from the bottom sur-
face 359 and top surface 366, respectively, as desired. Stand-
off brackets 361 and 363 may be arranged betweenthe metal shield
355 and bottom surface 359 and metal shield 357 and top surface
366, respectively. The perforations 360, 365 and 367 in the
shields 354, 355 and 359, respectively, are dimensioned relative
to the amplitude of the RF waves to prevent the same from pas-
sing therethrough by causing them to encounter the metal shield
and undergo reflections back therefrom.
During mild and warm temperature conditions, the oil
can expand and contract without restriction and flow through
the perforations 360, 365 and 367 so that it is available for
use. However, when the temperature conditions are cold and the
tank walls 356, 359 and 366 become cold, the viscosity of the
oil will increase so that the oil will not be able to flow through
the perforations 360, 365 and 367 and will tend to solidify in-
waxdly toward the shields 354, 355 and 357 forming a thick in-
sulation layer which is no longer capable of transferring ex-
q3~
Apparatus in accordance with Fig. 1 may be utilizedto maintain the fluency of the oil in the tank 352 which is lo-
cated interiorily of the shields 354, 355 and 357. As illus-
trated in Fig. 13, it is preferred to introduce RF waves from the
top of the tank 352 into a radiotransparent applicator 362 which
is liquid tight at its bottom end. Such an arrangement insures
against oil leakage from the tank 352 should the applicator 362
be damaged or fractured. The RF waves propagated through the
radiotransparent applicator 362 are deflected into the oil by the
energy deflector 364 where they are absorbed and converted into
thermal energy. However, the RF waves will not penetrate beyond
the shields 354, 355 and 357 but will be reflected back into the
oil by shields 354, 355 and 357, if -they have not already been
absorbed. As desired, ~e shield 357 across the top surface 366
of the tank 352 may be eliminated since the heated oil when it
cools will form a solid layer near the top surface 366. How-
ever, a small passage must be provided thr~ugh this top solid layer
for communicaticn with the heated oil below to provide a vapor
flow path to prevent implosion of the tank 352 should a void
develop between the heated oil below and the oil that has solidi-
fied to form the top solid layer. One technique for providing
such a liquid flow path is to provide piping 372 which transmits
heat from the anode cooling system of the magnetron 368 of the
RF generator 370 to the tank 352. The piping 372 e~tends
for a predetermined distance below the top surface 366 to pene-
trate any resulting solid oil layer by recirculating the deioni2ed
anode cooling solution through the piping 372 submerged in the
oil.
In applying the method and apparatus of the present
invention to coal, the order of production of the various fractions
present in the raw deposit has been found to be close to ideal.
-32-
~ 7~i
First water vapor and water is heated and expan~s to fracture
the substrate or bedding plan forming numerous flow paths through
which the water and the other fractions will flow into the well
bore. The resulting water which is condensed after distillation
is a high quality distillate with very low contamination. In
this regard, it should be noted that some of the lower order
lignites and subbituminous coals have a very high percentage of
water content, e.g., 30% or more. Sulfur gas is produced next
at approximately 230F. It can be stored in a closed system un-
til it is condensed and run through a kiln to reduce it to ele-
mental sulfur after which it can be stored in a stockpile. It
has been observed that when free sulfur gas is added to calcined
petroleum coke, it contacts the organic sulfur released by
pyrolysis and for some unknown reason, speeds the reaction.
Advantageously, the electromagnetic energy heating process
of the present invention removes sulfur at very low temperatures
to provide exceedingly rapid and efficient sulfur removal, ex-
hibiting characteristics similar to those of the aforementioned
reaction.
Next, the various gases and oil are produced. The gases
will vary accoraing to the particular coals from which they are
produced. The condensible end products such as propanes~ gaso-
lines and coal tars are separated and scrubbed. The non-
condensibles such as methane, carbon dioxide, carbon monoxide
and hydrogen sulfide can be used as fuel for electric genera-
ting equipment or stored for future use. Moreover, this fuel
is cleansed of contaminates so that the need for stack gas
scrubbers or electrostatic precipitators is eliminated.
The method and apparatus of the present invention can
be advantageously utilized for de-emulsifying hydrocarbon fluid
which consists of oil, basic sediment and water to separate the
the oil therefrom. However, it has been found critical when
heating the containea hydrocarbon liquid with RF energy, to
control the heating so that the water does not reach its boiling
point. If the water is heated above its boiling point, the
resulting steam will beyin to pen~trate the oil thereby further
creatin~ or assisting in maintalning the oil, ~asic sediment and
water emulsion. (However, it should be understood that in remov-
ing fractions from coal, the water in the coal can be heated beyon~
its boiling point, as desired, to facilitate the removal of water
as steam.) After such heating and a dwell time which may be fol-
lowed by additional heating as desired to optimize separation and
oil production, the liquid will separate into a top layer of clean
oil, a second layer of mostly oil with some water and basic sedi-
ment, and a bottom layer of clear water with basic sediment at
the bottom of the vessel. To speed up the removal of basic sedi-
ment ~rom the oil and further remove fines, salt water or brine
may be introduced into the top of the vessel and spread over the
separated and heated top layer of oil. The brine rapidly gravi-
tates downwardly through the oil due to its heavier weight so
that it accumulates and carries with it sediment present in the
oil.
The disposal of drilling mud has become a severe problem
for the oil industry. The method and apparatus of the present
invention can also be advantageously utilized for reconstituting
oil well drilling fluids such as drilling mud for reuse. This
is accomplished by applying RF waves to heat the liquids (pri-
marily water) in the drilling mud to their boiling point to boil
out the excess liquids, e.g., approximately 50~ of the water,
leaving behind a usable composition of bentonite r bairite salts,
etc., which may then be reclaimed. As desired, oil can also be
separated from the drilling mud and well bore cuttings. The re-
moved water which is in its vapor or steam phase may be compressed
into high pressure steam suitable for running a turbine.
Further, it is known that as oil is heated its volume
expands. Therefore, if ambient temperature oil is heated to 400~F,
the increase in volume would be nearly 40% greater than the
original volume. A 100F temperature increase fromambient causes
approximates a 5% expansion in the volume of the oil. The RF
energy heating process of the present invention can be effectively
-34-
3~
utilized to increase the yield of the oil due to the low eneryy
costs associated with generating RF waves to accomplish this
heating and the resulting expansion.
It is also known that water volume increases with in-
creasing temperature and that water has a much grea-ter dielectric
constant and loss tangent than oil, and therefore greater loss-
iness or ability to absorb electromagnetic energy than oil.
Therefore, RF energy will penetrate the oil film encapsulating
any water molecules and first heat the water molecules result-
ing in expansion of the same and rupture of the oil film. The
freed wa-ter molecules will combine with other water molecules
and sink to the bottom of the container, carrying basic sediment
with them. Moreover, the expansion of both oil and water dur-
ing the heating process will aid in removal of the oil from a
geological substrate. However, a supplementary drive mechanism,
such as steam injection which is shown in Fig. 10, may be used
to further facilitate removal, particularly after the expan-
sionary volume increase in the oil and water immediately ad-
jacent the end of the borehole has been exhausted.
It has further been found that the application of RF
energy in accordance with the method and apparatus of the present
invention to paraffinic oils causes the paraffin to homogenize
with the other hydrocarbons present in the oil so that it remains
in solution after application of the RF energy is terminated.
Such paraffin deposits often ultimately result in clogging or
a stoppage of flow. Thus, apparatus in accordance with the pres-
ent invention can be effectively used to clean pipelines, ves-
sels and other surfaces upon which paraffin is deposited. This
method is in stark contrast to heating by conduction which causes
the paraffin in paraffinic oils to cloud out of the fluid and
build up in pipelines, vessels and on other surfaces.
Advantageously, hydrocarbon fluids treated with RF en-
ergy in accordance with the present invention exhibit lower
pour points than hydrocarbon fluids treated with other conven-
tional heating techniques. This effect is particularly striking
~ 3 5
in oil produced from the kerogen present in oil shale. Moreover,
coal treated with RF energy in accordance with the present i.n-
vention enjoys a substantial increase in the yield of hydrocar-
bon as compared with conventional techniques
In operating the apparatus illustrated in Fig. 1,
the RF waves generated by the RF generator 16 are transmitted
to the radiotransparent applicator 18 through the waveguide por-
tions 44, 36 and 21. These waves are deflected outwardly into
the hydrocarbon fluid by the energy deflector 64. The temperature
rise in the various layers of the hydrocarbon fluid is then sensed
by the temperature sensors 60A-D which transmit signals represent-
ing temperature information to the controller 58. The controller
58 then controls the actuation of the motor 66 to move the energy
deflector 64 upward or downward to insure that the boiling point
of the fluid is n-ot exceeded in any portion thereof and to maximize
production and de-emulsification of the hydrocarbon fluid into
layers of clean oil, mostly oil with some basic sediment, and water
and basic sediment, while maintaining continuous full power of the
magnetron 17 to provide the greatest efficiency and prolong the
life of the filament or anode. Moreover, a gun barrel heater
75 may be utilized to further heat.the oil once the water has
been separated from the oil by electromagnetic energy heating and
the oil is sufficiently liquified to enable convection currents to
flow and aid in further reducing the viscosity and dropping out
fine sediment present in the oil. The oil may then be removed
through valves 74C and 74D. Additionally, gases and acids may be
removed, as desired. Any remaining residue of drilling mud or
basic sediment can be removed via access hatch 73.
The energy deflector 64 illus-trated in Fig. l is
enlarged in Fig. 2. However, it should be understood that the
energy deflector can be constructed as shown in Fig. 3 to con-
centrate the RF waves in a below horizontal payzone or coal seam
-36-
735
as shown in Fig. 4 to increase the volume over which the waves
are broadcast by diffusing the concentration of the RF energy;
as shown in Fig. 5 to provide a segmented or unidirectional broad-
cast which concentrates the RF energy over a specific broadcast
zone, e.g., over 30, and as shown in Fig. 6 to provide an ad-
justable angle of deflection to the energy deflector so that
the RF waves can be deflected upwardly, downwardly or at an an-
gle of 90, as desired.
In operating the apparatus 100 illustrated in Fig~
7, the output of the magnetron 106 is transmitted to the coaxial
waveguide 108 and tubular waveguide 116 and from there through the
radiotransparent applicator 118 to the energy deflector 120 where
the electromagnetic energy is deflected into the hydrocarbon fluid.
~fter the fluency of the hydrocarbon fluid has increased suf-
ficiently for ease of flow, the heated oil may be discharged
by, e.g., a suction pump 122. The deflected RF waves are ab-
sorbed by the oil and water mixture or penetrate slightly into the
inner skin of the internal walls, heating the oil trapped in
the pores, and then reflecting to another internal surface un-
til all of the energy is converted into heat in the fluid. If
desired, the energy deflector 120 may be preprogrammed to con-
tinuously or intermittently cycle to broadcast RF waves over
predetermined portion of the fluid volume. Further, as pre-
viously discussed, the RF energy will also remove rust and scale
from the interior walls of the vessel 102 to provide clean metal
surfaces in the oil stora~e compartments. The rust and scale
settles to the bottom of the vessel as basic sediment.
In operating the apparatus of Fig. 8 with oil yipe-
lines 144, RF energy (dotted arrows) is transmitted through the
waveguide 132 and the radiotransparent disc 138 into the T con-
nection 130 and the pipeline 144. The RF energy heats the oil
-37-
~ Z~3~735
reducing its viscosity while at the same time melking the paraffin
on the sidewalls of the pipeline 144 and in the T connection 130
to cause the same to homogenize with the other hydrocarbons in
the o.il and remain in solution.
In operating the apparatus of Fig. 9, RF waves gener-
ated by the magnetron 160 are transmitted to the applicator 188,
which includes an energy deflector (not shown), through waveguide
164, extension 166, adapter 170, flexible coaxial waveguide 174,
adapter 178, transition member 182, and waveguide 186. The posi-
tion of the energy deflector is adjusted in the applicator 188
in accordance with the output from a controller ~not shown)
which receives input signals from thermocouples 194, as described
with reference to Fig. 1. As described with reference to Fig. 1,
control sig~als are sent to a motor to drive a pulley which winds
or unwinds a cable to raise or lower the RF deflector attached
thereto in accordance with the temperature sensed by the therm-
ocouples 194. Additionally, the angle or incline of the conically,
shaped energy deflector may be adjusted to concentrate the RE'
waves in a particular payzone or to intercept the dip in a
coal seam. This adjustment can be accomplished by a remote or
proximate motor which moves the segments 95A-D of the deflector
93 illustrated in Fig. 6 inwardly and outwardly to change the
angle of deflection in response to output signals from the con-
troller.
The RF waves are deflected radially outward from
the applicator into the pay~one to heat the hydrocarbon material
causing the release of steam and gas, and increasing the fluency
of the hydrocarbon fluid so that the fluid flows into the bottom
of adjacent producing wells 154 (only one of which is shown in
Fig. 9). It should be understood that there will normally be
a plurality of producing wells adjacent to the injection well
-38
735
152 to receive the released hydrocarbon fluid. The pump set 200
of the producing well 154 will then pump the oil, water and gas
mixture through a production string 206 by movement of a sucker
rod 210. Advantageously, a supplementary gas drive system may
be used to inject gas into the annulus 199 between the injec~
tion well casing 190 and the waveguide 186 to aid in driving the
hydrocarbon fluid to the production well 154.
In operating the injectionwell 220 illustrated in
Fig. 10 to recover fractions from oil shale, coal, peat, lig-
nite or tar sands, the generated RF waves are transmitted to the
radiotransparent applicator 234 through a flexible coaxial wave-
guide 244, transition member 242 and waveguide 232. The RF waves
propagated through the applicator 234 are deflected by the energy
deflector 236 into the desired payzone 226 below the overburden
224. The resulting water, gas and oil fractions resulting from
the solidified oil in the vicinity of the applicator 234 flow
into the open hole sump 2~6, and expand upwardly in theannulus
254. Further, under the influence of drive means such as low
pressure extraction steam which is supplied through annulus 254,
additional fractionsare forced upwardly through the annulus 254.
The steam is received in a water line 260 which carries the vapor
and condensate to a demineralizer 262 and then to a condensate
tank 264 prior to application to the boiler 252. The boiler 252
produces high pressure steam to drive turbine 250 which drives
electrical generator 248 enabling it to supply power to the ~F
generator 246. The low pressure steam existing from the tur-
bine is applied to the annulus 254 through steam line 251.
Oil and gases, including hydrogen and sulfur, are
removed from thea~nulus 254 by line 258 which supplies the sa~e
to a separator 261 where the oil and gases are separated. The
oil is then transmitted to storage tan}~s prior to pipeline trans-
mission. The gases exiting from the separator 261 are applied to
a conventional gas separating system to provide oil, naphthalenes,
phenols, hydrogen, sulfides, and fuel oil.
735
The angled energy deflector Z80 shown in Fig 11
may be advantageously used in radiotransparent applicators for
geological substrates in which the payzone 2~4 is inclined rel-
ative to the injection well bore 282 to concentrate the RF en-
ergy in the payzone 284.
The coaxial waveguide 300 of Fig. 12 provides a
central conductor 316 or conduit through which oil can be pumped
to the surface, thereby eliminating the need for a supplementary
drive system. This arrangement can be used with above ground
vessels as well as for _ situ applications, as desired.
Further, referring to Fig. 13, in storage vessels
where it is desired to provide an insulating layer for the hydro-
carbon fluid contained therein, a portion of the hydrocarbon
fluid may be utilized to serve this function by utilizing a per-
forated metal shield 354 which is affixed to the interior side~
wall 356 of the tank 352. The shield 354 effectively shields
the layer of hydrocarbon fluid positioned between the sidewall
356 and the shield 354 from exposure to the RF waves. If in-
sulation is desired along the top surface 366 and bottom sur-
face 359, shields 357 and 355, respectively, can also be em-
ployed.
Under warm temperature conditions, the hydrocarbon
fluid within the vessel 352 has a sufficiently low viscosity to
enable the oil to freely flow through the perforations 360. How-
ever, in cold weather or under cold temperature conditions, the
viscosity of the oil will increase to the point where it can no
longer readily flow through the perforations 360. Additionally,
the shield 354 prevents the RF waves from heating the layer of
hydrocarbon fluid trapped between the interior sidewall 356 and
the metal shield 354. Thus, an insulating layer is formed by
the hydrocarbon fluid exterior to the shield 354 while the hydro-
carbon fluid interior of the shield 354 is heated by the RF waves
-40-
~ 3 ~
to maintain its fluency. The solid layer serves to insulak~ -the
interior heated oil, preventing heat loss to the surrounding
environment. If employed, the shields 357 and 355 function to
insulate the top and bottom surfaces 366 and 359, respectively,
in the same manner as shield 354 functions to insulate the side-
walls of the vessel 352. The heated anode fluid is circulated
into the vessel 352 through piping 372 which extends a sufficient
distance below the surface of the oil to provide a vapor passage
through the solidified top layer of oil to prevent implosion.
As previously discussed, the electromagnetic energy
to be employed will have a frequency or frequencies in the range
of 300 megahertz to 300 gigahertz depending upon the lossiness
of the fractions to be removed from the hydrocarbon material.
Such frequencies are selected for the most efficient absorption
of energy by the fractions to accomplish separation of two or
more dissimilar materials in the most efficient manner. How-
ever when employing multiple frequencies it may be desired to
also use electromagnetic energy having a frequency below 300
megahertz, e.g. such as 100 hertz for Bayol, with varying field
strengths, in accordance with the lossiness of the material.
It should be understood by those skilled in the art
that various modifications may be made in the present invention
without departing from the spirit and scope thereof, as described
in the specification and defined in the appended claims.
