Note: Descriptions are shown in the official language in which they were submitted.
CA 02823113 2013-08-09
HYDROCARBON RECLAMATION METHOD AND ASSEMBLY
FIELD
The present disclosure relates to a method and apparatus for recovery of
hydrocarbons found in mud, dirt, or tar sands; more specifically, for a method
of
mechanically and chemically treating hydrocarbon contaminated particles for
recovery of
the hydrocarbons and the environmentally acceptable disposal of the
particulate matter
utilizing a recirculating water stream.
BACKGROUND
Disposal and recovery of hydrocarbons found in oils, pit bottoms, pit sludge,
foul
sand, dirt around plants, drill cuttings, naturally occurring tar sands or
bitumen seams are
problematic in the industry because of the potential for contamination of
fresh water
bodies, and the waste of hydrocarbons bound up with the sand or drill
cuttings.
"Substrate" will be used herein to describe the constituent particles carried,
or which are
coated by, the hydrocarbon; and, it is believed that all forms of hydrocarbon-
coated
substrates could be remediated using this method. Drill cutting cleaning
methods and
apparatus are well known in the trade. Other prior forms of remediation of
these materials
depend on heating or incineration, or use abundant quantities of water or
other dangerous
chemicals.
The method and apparatus disclosed herein use neither heat nor noxious
chemicals,
and recirculates the water used for remediation of the hydrocarbons from the
substrate.
The chemical additives of this method are generally well known. Those
formulations
found in U.S. Patent No. 5,084,263 to McCoy et al. have been found to be
useful,
especially Solutions 1, 4, and 6, described in Cols. 7-9 of that patent which
is adopted by
reference herein. Other oil treating chemicals, such as commercially available
emulsion-
breakers and surfactants, can be adopted for use with this method.
SUMMARY
The described method for separating hydrocarbon-fouled particulate matter or
substrate comprises the steps of mixing the fouled substrate with water to
form a slurry
then placing the slurry in a contact tank to be fed through a vacuum eductor
with a water
1
CA 02823113 2013-08-09
=
and chemical mixture thus permitting a first separation of the hydrocarbons
from the
particulate matter. The slurry is allowed to settle in an oil separation tank.
The remaining
slurry output from the contact tank is mixed with additional water and moved
to a first
retention zone and cyclone system for additional separation of particulate
matter from the
slurry. From there, the output from the first retention zone and cyclone
system can move
to a mechanical shaker for separation of the solid particulate matter from the
remaining
water and return the water to a recirculating loop and collect hydrocarbons in
an oil
recovery tank by selective separation of the hydrocarbons from the particulate
matter for
removal. The hydrocarbon coating on the substrate is described as a "foulant"
but can be
economically valuable if removed from the substrate. Whether useful or subject
to
disposal the hydrocarbon foulant will be the material removed from the
substrate by this
process and the water and chemical mixture.
Specifically, a method for separating hydrocarbon-fouled particulate matter
can
comprise mixing the fouled particulate matter from a hopper by moving a water
and
chemical mixture through a vacuum-shearing eductor to form a slurry; placing
the slurry
in a contact tank to thoroughly coat the fouled particulate matter from the
eductor to form
a slurry of mixed water and chemical on a coated substrate; moving the slurry
into a series
of separation tanks permitting separation of the hydrocarbons from the
particulate matter
while allowing overflow of the separated hydrocarbon to the top of the each
successive
tank to a final collection tank and the particulate matter to be removed
through a vacuum
shearing eductor on the bottom of the each separation tank to an underflow
line;
selectively recycling the water and chemical mixture to the initial separation
tank and the
vacuum-shearing eductor on an inlet hopper from the final collection tank;
and, collecting
hydrocarbons in a recovery tank by skimming removal of the hydrocarbons from
each
separation tank in the series and moving the skimmed hydrocarbon to a
hydrocarbon
collection system. Additionally, the method can further comprise providing
sufficient
pressure to drive a water and chemical treatment mixture through a vacuum-
shearing
eductor on the series of separation tanks using one or more pumps; moving the
hydrocarbon-fouled particulate matter to at least one shaker and cyclone
separator,
separating solids from the water and chemical mixture; and discarding the
solids obtained
from the at least one shaker and cyclone separator and returning the water and
chemical
mixture to the initial vacuum shearing eductor for mixing with the hydrocarbon
fouled
particulates in the hopper.
2
CA 02823113 2013-08-09
=
This method for separating hydrocarbon-fouled particulate can also move the
remaining slurry output from the shaker through a desander/desilter system
into at least
one additional shaker for further removal of particulate matter to provide a
further
separation of water from the particulate matter; and, discard the solids
obtained from the
desander/desilter system and shaker and return the water and chemical mixture
to the
initial vacuum-shearing eductor for mixing with the hydrocarbon fouled
particulates in the
hopper.
The closed-loop hydrocarbon reclamation system is fashioned by combining a
collection hopper for the deposit of a hydrocarbon-contaminated substrate in a
slurry; a
vacuum-shearing eductor to coat each particle of the substrate with the water
and chemical
to facilitate separation of hydrocarbons from hydrocarbon-contaminated
substrate; a
hydro-cyclone retention tank connected to the vacuum-shearing eductor for
complete
mixing of the water and chemical mixture and hydrocarbon-contaminated
substrate; a
plurality of settling tanks connected to the hydro-cyclone for removal of
hydrocarbon-
contaminated substrate from the water and chemical mixture taken from the
bottom of
each settling tank through a vacuum-shearing eductor, permitting the
hydrocarbons
floating on the top of each successive settling tank to flow into a final
collection tank and
allowing the water and chemical mixture to be re-circulated to continue the
process and
the cleaned substrate to be discarded. Returned water is processed through an
ionizer to
facilitate breaking of an emulsion of hydrocarbon and water by electrochemical
means.
The ionizer is connected to a first settlement tank to ionize water flowing
through the
settlement tank. The hydrocarbon reclamation system permits each vacuum-
shearing
eductor on any separation tank to be independently controlled by a centralized
control
system to facilitate control of the movement of separated water from the
hydrocarbon
overflow from each separation tank. The output of any vacuum-shearing eductor
on any
separation tank can also move from each eductor to an accumulator which allows
the
output to flow into a scalping shale shaker allowing removal of particulate
matter from the
water and chemical transporting the particulate matter, then flow into a
desander/desilter
on a second shale shaker permitting the water to be returned to the first
settlement tank
and the remaining particulate matter to be removed from the water and chemical
stream.
3
CA 02823113 2013-08-09
=
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic process flow diagram of the apparatus to recover
hydrocarbons from particulate materials and water.
Fig. 2 is top plan view of the entire apparatus used for performing this
method.
Fig. 3 is a perspective view of the entire apparatus for accomplishing this
method.
Fig. 4 is a schematic process flow diagram of an alternative apparatus without
the
particulate handling devices of the apparatus shown in Fig. 1.
DETAILED DESCRIPTION
As shown in Fig. 1, this closed loop system uses water to wash and strip
hydrocarbons from sand or particulate matter through a combined weir and
shaker
system, assisted by a chemical bath to break the adhesion of the hydrocarbons
to the
particles. Input stream 10 provides the tar sands, bitumen, or contaminated
soils or clay
into a macerator 31 driven by motor 32 to break the larger pieces of material
into a smaller
grained material in hopper 30. This system is fabricated with an inlet tank 30
where
hydrocarbon substrate is introduced to the system, accomplished by a front-end
loader,
augur delivery systems or any other method of moving the hydrocarbon-coated
substrate
into the inlet tank 30. Water and chemical mixture, which is provided from
water source
185 and chemical tank 80, is circulated through the primed system to hopper 30
for the
initial wetting of the slurry.
The wetted slurry is moved out of hopper 30 from a flow of water and chemical
through shearing eductor 40 into line 50 and thereafter to hydro-cyclone 60
for continued
wetting and mixing. The hydro-cyclone 60 serves as an agitation retention tank
rather than
for separating or categorizing the outflow from the feed hopper 30. This could
be a mixer
or agitated tank without departing from the spirit or intent of this
disclosure.
The slurry, after leaving the hydro-cyclone 60, is moved through line 70 to
the first
separation/separation tank 110. The amount of chemical loaded into the system
from tank
80 through line 90 is controlled by automatic valve 100 which uses signals
from a
programmable logic control or centralized control system (PLC) to maintain the
proper
level of saturation within the system.
The first separation/settlement tank 110 allows the first separation of
hydrocarbons
from the particulate material which settle to the bottom where it is moved
through the
second shearing eductor 114 through line 118 to accumulator box 160'. From the
4
CA 02823113 2013-08-09
accumulator box 160' the water and chemical soaked particulate material moves
to the
scalping shaker screen 160 where the particulate matter that separates is
moved through
line 164 to the disposal line for solids 174. If the automatic sensors detect
excessive
hydrocarbon coating of the particulate matter moving through the discharge
line 174, a
second chemical tank 155 can be activated to coat the material prior to
disposal. Solids
sent from each of the shale shakers 160, 170 to the solids collection facility
where they can
be either disposed safely or, if useable as aggregate, to be recycled. This
final chemical
treatment can be made of the cuttings removed to assure complete removal of
residual
hydrocarbons on the particulate substrate removed through the shale shaker
output from
this second chemical tank 155, prior to disposal or recycling.
The finer particles, along with the water/chemical solution, are captured and
moved through line 168 to a desanding/desilter combination 171 where, after
removal of
material, they are moved into the second shale shaker 170. The finer
particulate material is
removed from the second shale shaker 170 through line 174 to be discarded in
the
particulate dump and the resulting water/chemical solution with the remaining
contamination is moved back into the first separation tank 110 where the
process
continues. Separated hydrocarbons which are less dense than the water float on
the top of
the first separation/settlement tank 110 and are moved from the first
separation/settlement
tank 110 to the second separation/settlement tank through an overflow skim
line 119. In a
similar fashion, the heavier and more dense particulate material with the
water/chemical
solution moves to the bottom of the second separation tank 120 where it is
removed
through the third shearing eductor 124 and moved through line 128 to
accumulator box
160' then through line 159 to the scalping shaker 160 where the process
described above is
repeated. The lighter hydrocarbon overflow from the second settlement tank 120
moves
through overflow line 129 to third settlement tank 130, where as previously
described, the
settled portion of water/chemical solution and particulate are removed from
the tank 130
with shearing eductor 134 and then through line 138 to accumulator box 160'
where the
shaker process is repeated.
The quiescent overflow from the third tank of hydrocarbons moves through line
139 to the final tank 140 where the top is removed through line 150 to the
hydrocarbon
collection system 150 which could be a pipe system or storage battery
depending on the
amount of hydrocarbons recovered from this process. The heavier water/chemical
solution
is returned to the closed loop system through line 184 where it is combined
with as much
5
CA 02823113 2013-08-09
fresh water from line 185 as needed to continually move the particulate
material through
the system through control valve 187. Motive force is provided by pump 186,
which, in
this embodiment, is a 40 HP motor moving the solution through line 188 to the
settlement
tanks and the original hopper 30. The initial shearing eductor moving the most
contaminated materials is provided a flow through pump 200 which in this
embodiment is
a 100 HP pump. This system also provides an ionizer 99 on the water/chemical
feed line
into first settlement tank 110. The ionized water facilitates the breaking of
the emulsified
oil/water mixture found in the re-circulated water/chemical mixture as a
function of the
zeta (C) potential from the ionizer 99.
Fig. 2 is a top view of the system described above. Inlet tank or hopper 30 is
filled
with the substrate having a coating of hydrocarbons as previously described.
The
macerator is not shown in this view. Hydro-cyclone 60 is situated between the
outflow of
the hopper 30 and the first settlement tank 110. Inlet tank 30 feeds to a
hydro-cyclone 60
which both continues the agitation and coating of the hydrocarbon-covered
substrate with
the water/chemical mixture before moving into the first separation/settlement
tank 110
where the initial separation occurs. Separated water and particulate matter
are moved into
the accumulator box 160' through line 118 and then into the scalping shale
shaker 160,
where the initial separation of particulate from the slurry of mixed
particulate and
water/chemical mixture occurs. The remaining slurry is then moved into the
desander/desilter 171 combination atop the second shale shaker 170 allowing
the water to
be returned through line 162 to the first precipitation/settlement tank 110.
The separation
of the hydrocarbon begun in the first separation/settlement tank 110 also
continues in the
second tank 120 where it is allowed to further separate from the
water/chemical mixture.
Settlement particulate matter is moved from tank 120 through line 128 into
accumulator
box 160' where it drops into the scalping shaker 160 and thereafter to the
desander/desilter
171 and the second shale shaker 170 permitting separated water to be returned
through
line 162 to the first precipitation/settlement tank 110. The same
separation/settlement
processing of the increasingly refined water occurs in the third tank 130
where the wetted
particulate matter is moved through line 138 in a similar manner into the
accumulator box
160' thence to scalping shaker 160 and then desander/desilter 171 and the
second shale
shaker 170 and back to the initial tank 110 to continue the process. As water
floats over
from tank 110 to 120 and from tank 130 through overflow lines 139 to tank 140,
it is
increasingly clarified and the particulate matter sinking to the bottom of the
tanks to be
6
CA 02823113 2013-08-09
removed through lines 118, 128, and 138 to the shaker system is increasingly
finer. The
water and chemical treatment is pumped through a vacuum-shearing eductor 40
where it is
mixed with the gravity-fed coated substrate and sheared as it moves through
the vacuum-
shearing eductor 40, and then into a separation/settlement tank 110. The
precipitated
particles of the substrate remaining in the water flow move in flow line 118
to the
accumulator box 160' and first shale shaker 160 (not shown in this view), and
then into the
desander/desilter combination 171 atop the second shale shaker 170 allowing
the water to
be returned to precipitation/settlement tank 110. Water continues to flow over
from the top
of each tank through tanks 110 to 120 then to 130 and finally into catch tank
140 where
the precipitated particles of the substrate remaining in the water are removed
through flow
lines 118, 128, 138 to accumulator 160'. At each step of the flowing over the
water is
clarified as more and more particulate matter settles out of the water. This
progressive
coating, settling, and separation steps may be repeated serially through any
number of
individual separation tanks and shale shakers without departing from the
spirit of this
disclosure which is only limited by the space required for its installation.
At least three
separation tanks and at least two shale shakers are considered optimal. The
final flow path
from tank 130 flows through the overflow lines 139 into the final catch tank
140. Pump
186 moves the remaining clarified water back into the process loop to continue
the
flushing process started in tank 110.
As shown in the front perspective details of Fig. 3, the system commences with
the
loading of the substrate from a process stream through macerator (not shown in
this view
for clarity purposes) into a feed hopper 30 which mixes the substrate with the
chemical
and water stream clarified by cycling through the system from line in vacuum-
shearing
educator 40. Water and treatment chemical from a water source tank move into
the
primed system before admission of substantial quantities of slurry in hopper
30 with the
hydrocarbon particles coating the sand. The mixed substrate and water mixture
is moved
through a line to a hydro-cyclone (not visible in this view) where it
continues to
thoroughly coat the slurry with the chemical introduced in the primed system
from the
water source tank and is fed to the first separation/settlement tank 110.
Water circulates
through this closed loop system from the final settlement tank 140 with pump
186 and is
supplemented with additional water through a flow line which returns through
the water
return line through an ionizer, all as previously described. The fully mixed
or coated
hydrocarbon and substrate is sheared in the vacuum-shearing eductor 40 then
moved into
7
CA 02823113 2013-08-09
=
=
the hydro-cyclone into the first separation/settlement tank 110. A variable
flow automatic
valve system permits the water/chemical mixture to be moved through a second
shearing
vacuum educator which again mixes the settled portion of the first
separation/settlement
tank 110 with additional fluid which is moved into the accumulator box 160'
through line
118, then to a scalping shaker 160. The mixture of particulates and
water/chemical
treatment is moved into the scalping shale shaker and again agitated to allow
heavier
particulate matter to be separated out and moved into the disposal line. In
this view the
scalping shaker is obscured from view by accumulator box 160', but the
desander/desilter
171, common in the fluids-handling art, are readily identifiable on the second
shaker 170
from which the solids are removed for disposal and the water/chemical solution
coating
the remaining finer solids are returned to the collection of separation tanks
commencing
with first separation tank 110 for recycling and further separation.
As shown in Fig. 4, an alternative embodiment of the described hydrocarbon
recovery system can also be fabricated from a similar arrangement of a
plurality of settling
tanks 110, 120, 130, and 140, into which a series of flows of hydrocarbon-
fouled
particulate matter or substrate 10 is allowed to progressively separate from
the water and
chemical carrier. As shown in the process diagram of Fig. 4, the overall
similarity of this
arrangement removes the particulate handling or removing devices shown in
Figs. 1-3 as
generally macerator on the initial hopper 30, accumulator box 160', shaker
160, and the
desanding/desilting filter system and shaker combination 170, 171, but retains
the
vacuum-shearing eductors 40 on the initial hopper, the hydro-cyclone 60,
before moving
the slurry into the first settling tank 110. A PLC system controls the rate of
flow both into
and out of each of the settling tanks 110, 120, 130 allowing them to remove
the particulate
matter from the bottom and allowing the separated hydrocarbon to rise to the
top and flow
from each tank in turn until collected in the final settlement tank. Water is
recycled from
the final settlement tank 140 to drive the shearing eductors 114, 124, and 134
on the
separation tanks while the separated oil is skimmed from the top of the final
settlement
tank 140. Particulate matter or cuttings are removed from the system by
selectively
diverting water from the bottom of the final settlement tank 140 through the
shearing
eductors on the settlement tanks to move particulates to the underflow line
118 filled with
the particulate matter coming off each settling tank 110, 120, and 130.
Additional water needed to keep the recirculation of the system is provided
through inlet 485 into first settlement tank 110. Water separated in each
settlement tank is
8
CA 02823113 2013-08-09
recycled through the initial vacuum-shearing eductor 40 from pump 200 on
return line 490
for moving the hydrocarbon-fouled slurry from hopper 30 into the hydro-cyclone
60 for
complete mixing, thence through line 70 into the first settlement tank 110.
Treating
chemicals for breaking the oil/water emulsion can be added from treating
chemical
injection system 480 as needed to maintain separation of the constituent parts
of the slurry.
Ionizer 499 provides an ionized electrochemical charge to the emulsion flowing
into the
first settlement tank to assist in separation of the water and hydrocarbon
emulsion.
Separated oil commences rising to the top of each settlement tank and moves
progressively through lines 119, 129, and 139 to the final separation tank
where it is
finally skimmed off and contained within a recovered oil collection system
150. This
could be either a tank system, or pipeline for moving the collected oil for
further
processing.
In the preceding description, for purposes of explanation, numerous details
are set
forth in order to provide a thorough understanding of the embodiments.
However, it will
be apparent to one skilled in the art that these specific details are not
required.
The above-described embodiments are intended to be examples only. Alterations,
modifications and variations can be effected to the particular embodiments by
those of
skill in the art without departing from the scope, which is defined solely by
the claims
appended hereto.
9
