Note: Descriptions are shown in the official language in which they were submitted.
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4883-45
This invention relates to a device for the com-
bustion of oil in the form of a slick on the surface of
open water or one which has sunk below that surface.
Oil spills are increasingly common and, espe-
cially with the huge capacity of modern oil tankers,
disastrous occurrences. ~Ihen a modern tanker runs
aground and breaks huge quantities of oil can be released
in the sea. However even accidental leakage of relati-
vely small quantities of oil can leave slicks of appre-
ciable size. The usual result is an environmental hazard
affecting fish and sea birds as well as wild life living
on the shore. Although several methods have been tried
for containing and removing the slicks these have proved
relatively costly and ineffective. Furthermore, other
than the method presented here, there exists no known
means for removal of a sunken oil slick. Also, no pre-
sent methods have been able to combust highly emulsified
oil slicks. The method outlined here will combust a 50%
emulsion of water and oil. The present known methods
include the use of containing the slick by a large number
of booms and its removal through application of oil
absorbing pads and detergents.
The present invention seeks to provide equip-
ment that is small, manouverable and can be transported
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to the site of an oil slick shortly after its release.
In this way the oil slick can be removed more easily. In
this regard it is particularly important to get to an oil
slick as soon as possible after the slick has been laid
down as at that time the volatile content of the slick is
high, thus assisting in combustion.
However if an oil slick has sunk because of an
increase in density with time or because of exposure to
sun and winds or because of its initially high specific
gravity, means is here provided to lift it to the sur-
face.
Accordingly, the present invention is a device
to combust an oil slick floating on a body of water, the
device comprising a hood; a container raised above the
water level to receive oil and water; a jet to force
mainly oil from the surface into the container or
containment ring; a combustion chamber; an atom;zing
gas transducer in the combustion chamber; means com-
municating the container and the atomizing gas
transducer; means to supply air or steam under pressure
to the atomizing transducer; a source of combustible gas
communicating with the combustion chamber; and means to
provide air to the combustion chamber.
The invention also enables floating a sunken
oil slick by providing a fine particle mist of oil and
air to be injected below the sunken slick to increase its
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buoyancy sufficiently to allow it to surface.
The present invention may be either mounted on
an independently movable vessel or may be adapted to be
towed by two other vessels in situations where a large
boom is required.
Aspects of the invention are illustrated,
merely by way of example, in the accompanying drawings in
which:
Figure 1 is a plan view illustrating generally
the use of the present invention in removing an oil
slick;
Figure la is a plan view of the means to
transport apparatus for lifting a sunken oil slick or
removing dangerous dissolved toxins;
Figure lb is a schematic view showing the means
of producing and injecting an oil air mixture below the
sunken oil or contaminant dissolved within the water;
Figure 2 is a schematic view illustrating the
main components of the device of the present invention,
Figure 2a is a schematic view illustrating an
alternative placement for the container receiving the
levitated oil;
Figure 2b is a schematic view illustrating an
alternative mounting method resulting from the use of a
flexible hose fuel intake allowed to float independently
of the main body;
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Figure 2c is a schematic view illustrating the
annular type of levitating jet;
Figure 2d is a schematic view illustrating a
method of concentrating the oil using a rectangular jet;
Figure 2e is a plan view of the apparatus shown
in Figure 2d;
Figure 3 is a side elevation of the device
mounted on a h~
Figure 4 is a plan view, partially in section,
of the embodiment of Figure 3; and
Figure 5 illustrates a detail useful on the
embodiment of Figures 3 and 4.
The drawings illustrate a device to combust an
oil slick 2 floating on a body of water 4. Referring
particularly to Figures 1 and 2 the device comprises a
hood 6 and a container 8, the container 8 being raised
above the water level to receive oil and water. There is
a jet 10 to force oil from the surface into the container
8. The jet 10 is annular and may be of rectangular or
circular cross section and is positioned by being
hingedly mounted at 12 and by the provision of floats 14.
This mounting permits the variation of the position of
the jet 10 below the water thus ensuring the correct
depth for proper operation is maintained.
There is a combustion chamber 16 which, as
shown in Figure 2, comprises a central stack 18 having an
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outer shell 20. There is a flap valve 22 positioned at
the top to control the temperature within the chamber 16;
opening it reduces the temperature. There is an ato-
mizing transducer 24 in the combustion chamber 16 which
is a sonic stem-jet atomizer. Although a stem-jet ato-
mizer is shown as an e~ample it will be appreciated that
other types of atomizers may be incorporated.
An annular ring 25 is suspended from the walls
of the combustion chamber and serves to redirect the
unburned gases downward to assure complete combustion and
to direct hot gases beneath the hood, through the lower
end of stack 18.
The atomizer transducer receives oil and some
water from the container 8 through conduit 26. The oil
is driven along conduit 26 by pump 28. In this regard
the container 8, which receives oil and water through the
open top from the jet, has an outlet 3~ in its top so
that oil may enter the conduit 26 and an outlet 32 at its
base so that water may return to the body of water 4.
There is a supply of compressed air 34 to the
atomizing transducer 24. The air impinges on the resona-
tor of the transducer causing a shock wave to be
generated atomizing the oil. The compressed air is fed
through conduit 36, controlled by valve 38 to the trans-
ducer 24.
There is a source of combustible gas, for
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lX69~318
example propane, contained in container 40. The gas
passes through conduit 42 controlled by valve 44 to a
burner jet 46.
It is desirable to provide a means to preheat
the oil and to this effect, as indicated in Figure 2, the
conduit 26 passes through passageway 64 between wall of
the stack 18 above the burner jet 46 having an associated
spark igniter 47 with its own high voltage supply (not
shown). A portion of the oil, suitably heated, is then
passed to the atomizing transducer through branch conduit
48. The rest passes through the conduit 26 back to the
jet 10 through check valve 50.
To further increase the efficiency of the
method, means is provided to generate steam from the heat
resulting in the combustion of the oil. Coils 51
(Figure 2) for this purpose are placed within the stack
and inlet 53 allows sea water to enter. The sea water is
changed to steam and drives turbine 55. This is coupled
by drive shaft 57 to drive fan 60. The steam generated
may also be used (instead of compressed air) to create
the required shock wave within the resonator of the stem-
jet transducer. A further benefit of producing steam is
better control of stack temperatures, thus eliminating
the need for exotic metals to withstand temperatures
above 2000F.
There is a pump 52 and a solvent container 54
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communicating through conduit 56 containing valve 58 with
conduit 26.
Combustion air is provided to the combustion
chamber 16 by the use of high volume fan 60 feeding air
through conduit 62. The fan 60 draws air through an
outer passageway 64 formed around the combustion chamber
16 and having an inlet 66. In this manner the fan 60
feeds warm air to the combustion chamber 16.
As a means of warming the temperature of the
air, and thus of the oil s'ick, under the hood 6 a
bypass 82 is provided on the outlet side of fan 60. The
bypass 82 is controlled by butterfly valve 84. At the
outlet of the bypass 82 there is a burner jet 86 supplied
by conduit 88 through valve 90. A source of combustible
gas, again for example propane, is stored at 92.
As shown particularly in Figures 1 and 2 the
device may be stabili~ed by the use of floats 94.
Furthermore the device may be towed by towing vessels 95
by lines 98. Electrical power supply may be passed
through the line 98 from the towing vessels 95.
In use the device is brought to the vicinity of
an oil slick 2. It may be towed or self-propelled as
discussed later. Flap valve 22 is closed to seal com
bustion chamber 16. Flap valve 84 is opened. Valves 44
and 90 are opened to allow propane to communicate with
the jets 46 and 86. The propane is ignited by a spark.
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The hot air resulting from the combustion of the propane
is directed under the hood 6 where it is trapped. The
high volume fan 60 is started and draws fresh air through
the inlet 66 through passageway 64 surrounding the com-
bustion chamber 16 and into the combustion chamber and to
the propane burner 46. Because it is drawn past the com-
bustion chamber 16 the air is heated before being
directed under the hood and to the jets 46 and 86. The
trapped hot air heats the underlying oil slick and thus
improves its fluidity. If necessary the solvent pump 5
is started, valve 58 is opened, and solvent is Eorced
through the jet 10 to lift oil from the water. The cross
sectional outlet of the jet is typically an annular rec-
tangle or circle - see Figure 2c - and it is a feature of
the present invention that it shows for the first time
that oil can best transfer mOmentum to oil and thus ele-
vate it higher, with less water and no emulsification.
After an initial injection of the solvent by jet 10 the
oil slick itself is used as the cleansing means and the
valve 58 may be closed and the pump 52 switched off.
Conduit 26 has a flexible portion near jet 10 and this,
together with the hinged mount 12 and the use of floats
14, permits positioning of the jet 10 at an appropriate
level beneath the surface. Valve 38 is opened and
compressed air or steam provided to transducer 24.
In the container 8 oil is skimmed from the top
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to enter conduit 30 and water passes through outlet 32.
To ensure that only water returns through the outlet 32
the rate of inflow and rate of outflow of the oil down
the conduit 26 are used to determine an ideal nozzle
diameter. Oil pump 28 delivers the collected oil and
solvent through conduit 26, to the transducer 24. The
transducer 24 ato-nizes the oil to form an extremely fine
mist. The mist is combusted by the flame issuing from
burner jet 46. Jets 46 and 86 o~ burning prop~ne may be
turned off once the combustion is underway. Small flap
valve 84 may be closed as the necessary heat 7'0r the oil
is now provided by the heat of the combustion chamber 16.
This is further controlled by opening or closing damper
22. As indicated the solvent pump 52 can be turned off
and the valve 58 closed unless the oil is heavily
weathered in which case it may be necessary to use the
solvent continuously.
The device is towed back and forth through the
oil slick 2 until all the oil is combusted.
While burning oil, any hazardous chemical con-
taminant in or with the oil may also be disposed of by
pumping it through coils 99 via port 105 (Figure ~) where
it is vaporized and conducted by conduit 101 and valve
103 to be used as a source of compressed gas for the
resonator of the stem-jet transducer. Thus both the oil
and toxic contaminant may be eliminated together.
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Further embodiments of the invention are
illustrated in Figures 2a and 2b. Figure 2a depicts a
sectioned view of an apparatus essentially the same as
that disclosed with the exception that nozzle 10 levita-
tes oil into container 8 which is secured directly to the
shell 20 of stack 18. Conduit 26 is thus greatly shor-
tened and lacks the spiral portion which surrounds stack
18. This embodiment is for use with small confined
slicks as all the oil removed by nozzle 10 and deposited
in container 8 is burned in the combustion chamber.
Accordingly only solvent issues from nozzle 10. The
spiral portion of conduit 26 is removed as the need for
heating of the oil is much reduced since the container 8
abuts and receives radiated heat. Otherwise the appara-
tus is operationally and structurally identical to that
previously disclosed.
Figure 2b illustrates a further embodiment of
the invention which makes the device suitable for opera-
tion by a single person. Container 8 is suspended from
floats (not shown) directly beneath stack 18 and is pivo-
tally mounted to arm 128 which is in turn secured to hood
6. In this instance conduit 26 comprises a flexible por-
tion extending from container 8 to the pump 28, and a
flexible portion extending from the pump to the nozzle
10. Conduit 48 extends from the container to the trans-
ducer 24. Conduit 48 is highly flexible and is attached
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to container 8 to float with it. Nozzle 10 is pivotally
mounted to container ~ by means of arm 129. Again, the
spiral portion of conduit 26 is omitted as the container
8 is sufficiently close to combustion chamber 16 to
receive radiated heat.
The attachment of the jet 24 by a flexible pipe
48 reduces the inertia of the system. The arrangement
ensures that the jet 24 does not have to follow the wave
motion which means it can operate in rough seas. In the
Figure 2d and 2e embodiment sea water is drawn through
intake pipe 26 and delivered by pump 28 to the rec-
tangular jet lO (shown in Figure 2c). This jet is
disposed almost horizontally 60 as to direct the oil
slick forward but inclined sufficiently upward to create
a mound 29 of water and oil at the entrance of a modified
horseshoe-shaped container 8a. Jet lO is preferably
pivotally mounted to this container 8a by arms 129. The
operation of this jet differs from the aforementioned
levitating jet in that sea water and not oil is used for
imparting a forward momentum to the slick. An advantage
of this embodiment is that the depth of this jet is less
critical than that of the levitating jet of Figures 2a and
2b and thus may be fixed if so desired. Regardless of
whether it is rigidly secured to the container or not,
the nozzle serves to eff~ctively "sweep" a surface face
of an oil slick. The advantages of this type of jet in
18
comparison to those conventional types which direct water
downwardly are that the oil slick is not driven below the
surface, no water-oil emulsion is formed, and there is no
aeration of the emulsion. The latter can cause a
decrease in fluidity and therefore a problem in pumping
or handling the collected oil slick. The rectangular
shape of the jet results in laminar rather than turbulent
flow, thus greatly increasing the rate of herding of the
slick. It also enables the formation of a stable mound
29 (Figures 2d and 2e~ of water which acts as a barrier to
prevent the accumulated oil from escaping from the con-
fined area formed between the walls of container 8a and
the mound of water. Containment results in sufficient
thickening of the oil layer to allow the floating branch
conduit 48 to remove mostly oil. The thickened oil also
results in less thermal loss to the underlying water
since thick oil acts as an insulator and thus aids in
maintaining a high under hood temperature. The structure
and operation of this device is otherwise identical to
that illustrated in Figure 2b.
An apparatus for floating a submerged oil slick
is also provided (see Figure lb). Parts common to
Figures discussed above have the same reference numerals
as in those Figures. A stem-jet 24a is placed in a
sealed compartment 120 below the oil slick 2. The com-
partment 120 is contiguous with a tube 122 having a
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plurality of holes or outlets 124. The compartment 120
and tube 122 are held in position below the water's sur-
face by weights 123 and towline 125. Compressed air from
supply 34, oil and solvent from container 54 are supplied
to the stem-jet 24a resulting in removal of any sea water
within the compartment. A shock wave is set up in the
resonating of the stem-jet transducer. A very fine mist
of oil and air is produced. This is fed through the
system of holes and is released into the water below the
sunken oil slick. This fine distribution of oil and air
attaches to the sunken slick resulting in its movement to
the surface. The solvent and very light oil result in an
increase of the oil slicks fluidity at the surface. This
apparatus is towed as shown in Figure la.
When all the oil slick has risen the procedure
for burning is the same as for an oil slick found origi-
nally on the surface. In the event that the sunken slick
is a very great distance from the surface, which might
result in static pressures too high for compressed air,
then a mechanical emulsifier (not shown) using light oil
and water may be employed. The oil and water mixture
replaces the compressed air of the aforementioned method
while the apparatus operates in an identical manner. The
light oil can be relatively harmless vegetable oil, for
example.
The same procedure is used to remove toxins
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such as D.D.T. The oil absorbs D.D.T. about lO00 times
more readily than water and will thus cause it to leave
the latter after exposure to oil which is distributed
within it. Since emulsified oil and water take a while
to surface this process is speeded up by a demulsifica-
tion process. A suitable demulsifier is injected through
conduit 26 and ejected as a fine spray through 24a. To
allow this valve 160 controls a supply of demulsifier
from a container 162 to feed into conduit 26. The
apparatus of Figure lb also has a power amplifier 164
connected by line 166 to a row 168 of sonic transducers,
for example ceramic or magnetostrictive transducers.
As the demulsifier spreads the row 168 of sonic
transducers are activated by power amplifier 164. The
sonic energy created is beamed upwards causing not only
the demulsifier to increase its activity but also in
absorption of the D.D.T. resulting in a rapid surface
layer formation of D.D.T. (or other toxin) which can then
be burned as described.
Referring to the remaining Figures, the vessel
of Figures 3 and 4 has a hull 96 but otherwise has the
features shown in Figure 2. In addition the device may
desirably use a plurality of atomizing transducers 24 as
shown particularly in Figure 4. As shown particularly in
Figure 3 the control valves 38, 44, 58, 90 and the like,
propane supply for jets 46, and 86, oil pump 28 and the
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control valves may be positioned in the hull 96 in com-
partments 126.
The device, as shown particularly in Figure 4,
also features a plurality of jets 10 to force oil from
the surface to container 8. Burner jets 46 are also pro-
vided in the area adjacent jets 10 to provide heat and
thus reduce the viscosity of the oil.
The jets 10 are mounted on a boom or fin 100 so
that they may be pivoted to govern their position rela-
tive to the water surface. The mechanism is hingedly
attached at 102 and, as shown particularly in Figure 5,
each jet is mounted on a rigid rod 104. The rod pivots
at 106 and a distal end of the rod is attached to
piston 108 within cylinder 110. ~ydraulic fluid enters
the other end of the cylinder 110 through conduit 114
communicating with master cylinder 116. Hydraulic fluid
is driven from the master cylinder 116 by motor 118.
Whether to drive fluid is determined by computer 120,
shown schematically but designed to sense the speed of
the hull 96 relative to the water and to send the
appropriate signal to the motor 118. The motor 118
speeds or slows, as required, thus varying the supply of
hydraulic fluid from the master cylinder 116 to the
cylinder 110. In this way the pis~on 108 is moved in the
cylinder 110 to move rod 104 to vary the depth of the
jet 10.
1~i99~8
The present invention thus provides a simple
craft that can be used to burn large quantities of oil
quickly. By use of the atomizing transducer the oil is
provided as a fine spray which can be easily ignited by
the combustion means described. It should be noted that
the oil slick itself is used for its own removal. The
discovery that oil can best transfer momentum to oil and
thus lift it at a very high velocity îs a particular
feature of the present invention. The use of oil to lift
oil above its surface enables the use of jets th~t are
rectangular in shape and yet maintain lifting power.
This rectangular jet is ideal for lifting large volumes
of oil in very thin oil slicks. In addition, the annular
design of the levitating jet enables performance in oil
which has very little fluidity. A further result of this
new type of jet is that highly aerated liquid (froth)
may be easily levitated, improving the separation process
in mining and bitumin extraction processes.
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