Note: Descriptions are shown in the official language in which they were submitted.
CA 02610124 2007-11-09
MOBILE OIL SANDS MINING SYSTEM
Field of the Invention
This invention relates to mining technology and a method for the processing of
recovered bitumen bearing oil sands from the earth. More particularly, the
invention
relates to a mobile system of equipment for increasing the efficiency of the
ore mining
operation.
Background of the Invention:
The Northern Alberta Tar Sands are considered to be one of the world's largest
remaining oil reserves. The tar sands are typically composed of about 70 to
about 90
percent by weight mineral solids, including sand and clay, about 1 to about 10
percent
by weight water, and a bitumen or oil film, that comprises from trace amounts
up to as
much as 21 percent by weight. Typically ores containing a lower percentage by
weight of bitumen contain a higher percentage by weight of fine mineral solids
("fines") such as clay and silt.
Unlike conventional oil deposits, the bitumen is extremely viscous and
difficult to
separate frum the water and mineral mixture in which it is found. Generally
speaking,
the process of separating bitumen from the tar sands comprises six broad
stages. 1)
Initially, the oil sand is excavated from its location and passed through a
crusher or
comminutor to comminute the chunks of ore into smaller pieces. 2) The
comminuted
ore is then typically combined with hot process water to aid in liberating the
oil. The
combined tar sand and hot water is typically referred to as a "slurry". Other
agents,
such as flotation aids may be added to the slurry. 3) The slurry is then
passed through
a "conditioning" phase in which the slurry is allowed to mix and dwell for a
period to
create froth in the mixture. The term "conditioning" generally refers to a
state
whereby the slurry is sufficiently mixed and aerated that a commercially
viable
amount of the bitumen has left the mineral component to form an oily film over
the
bubbles in the slurry. 4) Once the slurry has been conditioned, it is
typically passed
through a series of separators for removing the bitumen froth from the slurry.
5) After
the slurry has been sufficiently processed to remove the maximum practical
amount of
bitumen, the remaining material, commonly known as the "tails", is typically
routed
1
CA 02610124 2007-11-09
into a tailing pond for separation of the sand and fines from the water. Due
to the time
required to clarify the tailings water, the process requires the continual
addition of
fresh water. 6) The separated bitumen and water is then delivered to a
secondary
extraction process that further removes mineral and water content and provides
a
diluted bitumen product for delivery to an upgrader that converts the bitumen
into a
commercially usable product.
It has been recognized for a long time that, since the bitumen comprises a
relatively
small percentage by weight of the ore initially extracted, separation of the
mineral
content from the ore as soon as possible after excavation would lead to the
most
efficient and cost effective mining process. It has also been recognized that
it would
be useful to immediately recycle the process water used to create the slurry
rather than
the current requirement of continually using fresh water due to the slow
process of
clarifying tailings water. While these advantages have been known, to date
there has
been no commercially viable method of extracting the mineral content soon
after
excavation and recycling the process water. Generally, the sand and fines
settle out of
the tails at different rates with the fines taking a long time to settle out.
This results in
a tailings pond comprised of a sand deposit, a suspension of fines and water,
and a
thin layer of clarified water on the top of the tailings pond. While the thin
layer of
clarified water is clean enough that it may be siphoned off and recycled as
process
water, the bulk of the water remains trapped in the suspension. Furthermore,
as
settling progresses, the settled fines trap a significant percentage by weight
of water.
The net result has been extensive tailings ponds that require significant
contaniriment
structures and associated ongoing maintenance as well as increasing
transportation
costs as the tails must be transported to new tailings deposition sites as
existing ponds
are filled. Handling the tails and transporting them to available tailings
ponds has
become a difficult and expensive logistical problem in mining the oil sands.
Additionally, a large volume of water is tied up in existing ponds,
necessitating a
large ongoing demand for fresh process water.
Over the years, a variety of methods have been used to process and transport
the sand
from the excavation site. Initially, oil sand excavation and transport were
completely
mechanical via conveyor belts extending from the mine face to a large facility
for
processing the mined ore. As mining progressed the conveyors lengths were
increased
2
CA 02610124 2007-11-09
to transport ore from the receding mine face to a large processing facility.
The use of
conveyors led to many difficulties including high energy costs and mechanical
breakdown which led to work stoppage. As mining continued, the use of
conveyors to
transport the ore over extended distances became unworkable.
Large ore trucks were instituted to replace the conveyor system for
transporting ore
from the mine face to the processing facility. The ore trucks, however, are
expensive
to purchase and operate and often create inefficiencies in the production
process.
As described in Canadian Patent No. 2,029,795, it was determined that it was
preferable to deliver the ore by truck from the mine face to an intermediate
site where
the ore would be crushed and combined with hot process water at a slurry
preparation
facility to create a pumpable slurry for transport through a pipe. This "hydro-
transport" process served the dual purpose of efficiently transporting the
slurry from
an intermediate site relatively near the mine face to the large processing
facility and
allowing time for the slurry to be sufficiently conditioned on route. Provided
the
hydro-transport was over a sufficiently large enough distance that the dwell
time in
the pipe was sufficiently long, typically at least 1 kilometre, the slurry
would arrive at
the processing facility already conditioned and ready for separation. Thus,
the
previously required separate conditioning step could be omitted from the
process.
While the hydro-transport solved some of the difficulties with transporting
the ore
from the mine site face to the separation facility, it did not solve the long
term need to
reduce the mechanical transport of large volumes of mined oilsand from the
mine face
to the intermediate site. As will be appreciated, continual excavation results
in the
active mine site face being located further and further from the crusher and
slurry
preparation facility. Solutions to date have typically relied on constructing
longer
conveyor belts to transport the ore, or use additional trucks, to move the ore
from the
mine face to the slurry facility at the intermediate site. Though these
solutions provide
temporary relief, they do not solve the inefficiency of transporting the
mineral
component further than required.
One concept was to do away with the transport step completely by locating all
of the
ore processing machinery near the mine face. An example of this concept is
disclosed
3
CA 02610124 2007-11-09
in Canadian Patent No. 2,092,121 and Canadian Patent No. 2,332,207. These
references disclose a single mobile excavator and bitumen extraction facility,
commonly referred to as a tar sand combine, that follows the mine face as
digging
progresses. This solution is not ideal as it requires the continuous transport
of a large
amount of extremely heavy machinery and water including a slurry preparation
facility. In addition, connections to the hydro-transport pipeline and process
water
supply line must be continuously extended as the combine advances. Further,
some
embodiments suggest separating the mineral component at the mine face. Since
the
slurry must first be conditioned prior to separation, these embodiments
require the
continual transport of large volumes of slurry as it is conditioned.
In Canadian Patent Application No. 2,453,697, the idea of a process line
comprising a
combination of mobile and relocatable equipment units at the face of an oil
sand mine
site is suggested. The '697 application proposes a process comprising a mobile
excavator that advances along a mine face, a mobile comminutor that advances
behind the excavator to crush the mined ore to a conveyable size, and a
relocatable
conveyor that extends along the mine face for receiving the crushed oil sand
and
conveying it to a relocatable slurry facility for preparing slurry for hydro-
transport.
The slurry facility may be connected directly to a fixed pipe for hydro-
transport. The
process line of the '697 application allows for relatively small components,
such as
the excavator and comminutor, to be mobile and follow the mine face as digging
progresses. Less transportable equipment such as the slurry facility and hydro-
transport pipe, are relocatable. That is, they are stationed in a fixed
location for an
extended period of time (months), but may be relocated once the excavator has
removed all of the ore within near proximity to the relocatable conveyor.
The disclosure of the '697 application suffers from several limitations.
First, the
dwell time of the slurry facility is determined solely by the rate of
excavation and the
length of the first relocatable conveyor. Thus, to increase the dwell time in
a
particular location, either the rate of excavation must be slowed or the
length of the
conveyor must be increased. The Northern Alberta region has extremely harsh
weather conditions and it has been found that extensive conveyors consume a
considerable amount of energy, and are prone to break down resulting in work
stoppage. For this reason, the length of the conveyor is preferably not overly
long.
4
CA 02610124 2007-11-09
However, it is also desirable that the slurry facility be relocated as seldom
as possible
necessitating a minimum length of conveyor in order to access a suitable
volume of
ore to supply the slurry facility. An additional limitation of the '697
application is that
a practical relocatable slurry facility or relocatable desanding facility is
not disclosed.
A further problem faced by the industry is the extensive use of water to
extract the
bitumen from the ore. While the sand portion of the mineral component may be
practically removed from the slurry, the fine tailings, clay and other fine-
sized
material, is difficult to remove from the tailings and tends to remain in
suspension.
The solution to date has been to store the tailings in ponds for a sufficient
period to
allow the fines to settle out of the water. It has been determined, however,
that it takes
an extremely long period of time for the fines to settle out, resulting in
ever increasing
tailings ponds. Additionally, water becomes trapped in the interstitial
spacing between
particles so that even after the fines have settled a large amount of water is
trapped in
the settled material. Other than the excessive water requirements, tailings
ponds create
an environmental and logistical challenge as tailings must be continually
disposed of
in the continuously growing volume of tailings ponds which must be contained
and
maintained for years. There thus exists a need for a method of processing oil
sands
that obviates the need for extensive tailings ponds and provides for the
recycling of
water from the tails soon after deposition at a deposition site.
A further limitation of the prior art is that there is no practical solution
provided for
handling tailings. Rather, current deposition methods result in a separation
of a course
tails and a fine tails, maintaining the need for extensive tailings ponds to
provide
settlement of the fine tailings component. There thus exists a need for a
method of
processing oil sands that produces a whole dry tails comprising both the sand
component and the fine tailings.
There thus exists a need to increase the efficiency of excavation and
transport
processes to reduce operating costs. There exists an additional need to
increase the
operating period for an excavator servicing a transportable slurry facility,
without
increasing the distance of ore transport from the excavator to the facility.
There exists
a further need for a process capable of removing the mineral component of the
oil
5
CA 02610124 2014-08-25
sands at a proximate location to the mine face without the creation of
extensive
tailings ponds.
Summary
In accordance with one aspect of the invention, there is provided a method of
increasing a dwell time of an ore handling apparatus between relocations
thereof
while keeping the ore handling apparatus within operational reach of at least
one
receding mine face. The method includes:
positioning a first mining conveyor having a first discharge end and a first
distal end such that the first discharge end is in communication with a first
ore
receiving location of the ore handling apparatus;
positioning a second mining conveyor having a second discharge end and a
second distal end such that the second discharge end is in communication with
a
second ore receiving location disposed along the first mining conveyor;
excavating a first body of ore within operational reach of the second mining
conveyor, and conveying the excavated first body of ore via the second mining
conveyor to the first mining conveyor, and via the first mining conveyor to
the first
ore receiving location of the ore handling apparatus;
repositioning the second mining conveyor and repositioning the second ore
receiving location along the first mining conveyor to maintain the second
discharge
end in communication with the second ore receiving location;
excavating a second body of ore within operational reach of the repositioned
second mining conveyor, and conveying the excavated second body of ore via the
second mining conveyor to the first mining conveyor, and via the first mining
conveyor to the first ore receiving location of the ore handling apparatus;
rotating the second mining conveyor generally about the second discharge
end; and
excavating a generally arc sector shaped third body of ore within operational
reach of the rotated second mining conveyor and conveying the excavated third
body
6
CA 02610124 2014-08-25
of ore via the second mining conveyor to the first mining conveyor and via the
first mining conveyor to the first ore receiving location of the ore handling
apparatus.
Rotating the second mining conveyor may include rotating the second mining
conveyor generally about the first distal end of the first mining conveyor.
The method may further involve positioning a third mining conveyor having a
third discharge end and a third distal end such that the third discharge end
is in
communication with the first ore receiving location of the ore handling
apparatus.
The method may further involve positioning a fourth mining conveyor having
a fourth discharge end and a fourth distal end such that the fourth discharge
end is in
communication with a third ore receiving location along the third mining
conveyor.
The method may further involve rotating the fourth mining conveyor
generally about the fourth discharge end to extend the operational reach of
the fourth
mining conveyor to facilitate excavating a generally arc-sector shaped fourth
body of
ore within operational reach of the rotated fourth mining conveyor, and
conveying the
excavated fourth body of ore via the fourth mining conveyor to the third
mining
conveyor, and via the third mining conveyor to the first ore receiving
location of the
ore handling apparatus.
The method may further involve initiating excavation of ore using a mobile
excavator, comminuting excavated ore with a mobile comminutor having a
discharge
end in communication with the second mining conveyor, causing the excavator to
take multiple relocation steps to excavate a body of ore about the mobile
comminutor
while the mobile comminutor remains in a first location until substantially
all ore
within operation reach of the mobile comminutor at the first location has been
excavated, relocating the mobile comminutor to a second location closer to a
new
mine face exposed by the excavator, and relocating the mobile excavator to
excavate
the new mine face.
The method may further involve relocating the ore handling apparatus from a
first ore handling location to establish a new ore handling location for the
ore
handling apparatus, relocating the first and second mining conveyors to
facilitate
excavation of new bodies of ore including at least one arc-sector shaped body
of ore
6a
CA 02610124 2014-08-25
within operational reach of the new ore handling location for the ore handling
apparatus, and conveying the excavated new bodies of ore via the second and
first
mining conveyors to the new ore handling location for the ore handling
apparatus.
The method may further involve positioning at least one mining conveyor to
facilitate excavation of unexcavated ore located between the third and fourth
bodies
of ore, wherein a discharge end of the at least one conveyor is placed in
communication with the first ore receiving location of the ore handling
apparatus, and
excavating while rotating the at least one conveyor until substantially all of
the ore
between the third and fourth bodies of ore has been excavated and conveyed via
the at
least one conveyor to the first ore receiving location of the ore handling
apparatus.
The method may further involve simultaneously conveying ore via the first,
second, third and fourth mining conveyors to the first ore receiving location
of the ore
handling apparatus.
The method may further involve operating the first and second mining
conveyors to convey excavated ore to the first ore receiving location of the
ore
handling apparatus while the third and fourth conveyors are inoperative, and
operating the third and fourth mining conveyors to convey excavated ore to the
first
ore receiving location of the ore handling apparatus while the first and
second
conveyors are inoperative.
The first and second mining conveyors may be of substantially different
length to facilitate excavating a mine face wall having an orientation that is
parallel to
neither the first nor the second mining conveyor.
The method may further involve repositioning the first mining conveyor while
maintaining communication of the first discharge end with the first ore
receiving
location of the ore handling apparatus, and repositioning the second mining
conveyor
to facilitate excavation of ore at a series of locations within operational
reach of the
repositioned second mining conveyor while maintaining alignment of the second
discharge end with the first mining conveyor.
The method may further involve rotating the second mining conveyor
generally about the first distal end of the first mining conveyor.
6b
CA 02610124 2014-08-25
The method may further involve excavating a first mine face along the first
mining conveyor until substantially all high yield ore within operational
reach of the
first mining conveyor has been mined up to a low yield body of ore, and
rotating the
second mining conveyor generally about the second ore receiving location to
facilitate excavating a second mine face along the second mining conveyor
until
substantially all high yield ore within operational reach of the second mining
conveyor has been excavated up to the low yield body of ore, wherein the first
mine
face is oriented in a different direction than the second mine face.
The method may further involve rotating the second mining conveyor
generally about a movable mobile hopper on the first mining conveyor.
The method may further involve rotating the first mining conveyor generally
about the first ore receiving location of the ore handling apparatus to
further facilitate
excavating substantially all the high yield ore up to the low yield body of
ore.
The first ore receiving location may include a transfer conveyor associated
with the ore handling apparatus.
The ore handling apparatus may include a mobile slurry facility.
At least one of the first and second mining conveyors may include a mobile
mining conveyor having at least one powered drive operable to reposition the
mobile
mining conveyor.
The second and fourth mining conveyors may be of substantially different
lengths to facilitate excavating a maximum amount of high yield ore located
around a
low yield body of ore while minimizing conveyor movement.
The ore handling apparatus may include a transfer conveyor.
The ore handling apparatus may include a slurry facility. The slurry facility
may be configured to be mobile.
The ore handling apparatus may include a comminuting device.
The first ore receiving location may include a hopper adapted for receiving
ore.
6c
CA 02610124 2014-08-25
In accordance with another aspect of the invention, there is provided a method
of increasing a dwell time of an ore handling apparatus between relocations
thereof to
keep the ore handling apparatus within operational reach of at least one
receding mine
face, wherein the method involves:
positioning a first mining conveyor having a first discharge end and a first
distal end such that the first discharge end is in communication with a first
ore
receiving location of the ore handling apparatus;
positioning a second mining conveyor having a second discharge end and a
second distal end such that the second discharge end is in communication with
a
second ore receiving location disposed along the first mining conveyor;
excavating a first body of ore within operational reach along a length of the
second mining conveyor, and conveying the first body of excavated ore via the
second mining conveyor to the first mining conveyor, and via the first mining
conveyor to the first ore receiving location of the ore handling apparatus;
repositioning the second mining conveyor to reposition the second ore
receiving location along the first mining conveyor, excavating a second body
of ore
within operational reach along a length of the repositioned second mining
conveyor,
and conveying the second body of excavated ore via the repositioned second
mining
conveyor to the first mining conveyor, and via the first mining conveyor to
the first
ore receiving location of the ore handling apparatus; and
rotating the second mining conveyor generally about the second discharge end
while keeping the second discharge end in communication with the first mining
conveyor to facilitate excavating a generally arc-shaped third body of ore
within
operational reach along a length of the rotated second mining conveyor,
excavating
the third body of ore including from a plurality of excavation locations
alongside the
rotated second mining conveyor, depositing excavated ore from the plurality of
excavation locations onto the second mining conveyor at a corresponding
plurality of
ore receiving locations along the length of the rotated second mining
conveyor, and
conveying the third body of excavated ore from the plurality of ore receiving
locations along the length of the rotated second mining conveyor to the first
mining
6d
CA 02610124 2014-08-25
conveyor, and via the first mining conveyor to the first ore receiving
location of the
ore handling apparatus.
Rotating the second mining conveyor may include rotating the second mining
conveyor generally about the first distal end of the first mining conveyor.
The method may further involve excavating a first mine face along the first
mining conveyor until substantially all high yield ore within operational
reach of the
first mining conveyor has been mined up to a low yield body of ore, and
rotating the
second mining conveyor generally about the second ore receiving location of
the first
mining conveyor to facilitate excavating a second mine face along the second
mining
conveyor until substantially all high yield ore within operational reach of
the second
mining conveyor has been excavated up to the low yield body of ore, wherein
the
second mine face is oriented in a different direction than the first mine
face.
The method may further involve rotating the first mining conveyor generally
about the first ore receiving location of the ore handling apparatus to
facilitate
excavating substantially all high yield ore up to the low yield body of ore.
Each of the plurality of excavation locations may be operationally proximate
to a respective one of the corresponding plurality of ore receiving locations
along the
length of the second mining conveyor.
Excavating the first, second and third bodies of ore may include excavating at
least first, second and third mine faces, respectively, and wherein the second
and third
mine faces are not generally parallel to each other.
The steps of repositioning and rotating the second mining conveyor may
together facilitate mining along a mine boundary that is neither parallel nor
perpendicular to the first mining conveyor.
The mine boundary may be in a generally straight line.
6e
CA 02610124 2014-08-25
Brief Description of the Drawings
In drawings which illustrate, by way of example only, illustrative embodiments
of the
invention,
Figure 1 is an illustration of an embodiment of the process of the present
invention.
Figure 2 is a top view illustration of an embodiment of the process line of
the present
invention.
Figure 3 is a top view illustration of an embodiment of the present invention.
Figure 4 is a side view illustration of an embodiment of the present
invention.
Figure 5 is a side view illustration of an embodiment of the present
invention.
Figure 6 is a side view illustration of an embodiment of the present
invention.
Figure 7 is a side view illustration of an embodiment of the present
invention.
Figure 8 is a side view illustration of an embodiment of the present
invention.
Figures 9a-9c are top view illustrations of an embodiment of the present
invention.
Figures 10a-10f are top view illustrations of an embodiment of the present
invention.
Figure 11 is a top view illustration of an embodiment of the present
invention.
Figure 12 is a process illustration of an embodiment of the present invention.
Figure 13 is an isometric illustration of an embodiment of the present
invention.
Figure 14 is a side view illustration of an embodiment of the present
invention.
Figure 15 is a bottom view illustration of an embodiment of the present
invention.
Figure 16 is a side view illustration of an embodiment of the present
invention.
6f
CA 02610124 2014-08-25
Figure 17 is a schematic view showing an embodiment of a modular, mobile
extraction system according to an aspect of the present invention
incorporating a
plurality of mobile cyclone separation stages forming a mobile cyclone
separation
facility and a mobile froth concentrator vessel defining a mobile froth
concentration
facility.
Figures 18a to 18f are schematic plan views showing embodiments of the present
invention.
Figures 19a to 19c are schematic plan views showing embodiments of the present
invention.
Figures 20a and 20b are schematic plan views showing an embodiment of the
present
invention.
Detailed Description
In one embodiment, a process line is provided for mining an oil sands ore
body,
the process line comprising an excavator for mining oil sands ore; a
comminutor for
receiving mined ore from the excavator, comminuting the mined ore to
conveyable
size and transferring the comminuted ore to a mobile conveyor for transporting
the
comminuted ore; the mobile conveyor having a free end, a discharge end and at
least
one drive for advancing the conveyor through an operational arc generally
about the
discharge end; whereby the excavator mines a section of ore within operational
reach
along the length of the mobile conveyor and supplies the mined ore to the
comminutor, and the comminutor supplies conveyable ore to the mobile conveyor,
and whereby the mobile conveyor is periodically moved about the discharge end
to
locate another portion of the ore body within operational reach of the mobile
conveyor until substantially all of the ore body within the operational arc
has been
mined.
In a further embodiment, a mobile conveyor is provided for transferring mined
oil
sands ore from a mine face, the conveyor comprising: two or more
conveyor
sections; each of the two or more sections having at least one drive for
advancing the
conveyor, and at least one alignment device for detecting misalignment between
at
7
CA 02610124 2014-08-25
least one adjacent section and controlling the drive responsive to a detection
of
misalignment to align adjacent sections.
In a further embodiment, a method is provided of mining oil sands ore with a
mobile conveyor, the method comprising:
at a first conveyor position:
excavating and sizing ore at a mine face within operational reach of the
first position;
transferring the sized ore to the conveyor;
conveying the sized ore along the conveyor; and
discharging the sized ore;
after excavating, sizing and transferring substantially all the ore within
operational reach of the conveyor in the first conveyor position, advancing
the
conveyor generally about the discharge end to a second conveyor position; and,
excavating, sizing and transferring substantially all the ore within
operational reach of
the conveyor at the second position.
In a further embodiment, a method is provided of mining oil sand ore with a
mobile conveyor, the method comprising: excavating, sizing and transferring to
the
conveyor all ore within operational reach along the length of the conveyor;
conveying
the sized ore along the conveyor to a discharge end of the conveyor; advancing
the
conveyor generally about the discharge end to locate the conveyor within
operational
reach of a further section of oil sand ore; excavating, sizing and
transferring to the
conveyor all ore in the further section within operational reach along the
length of the
conveyor; continuing to advance the conveyor about the discharge end to locate
the
conveyor within operational reach of additional sections of oil sand ore and
after each
advancement excavating, sizing and transferring the respective additional
section of
oil sand ore, until substantially all ore within an operational arc sector
generally about
the discharge end has been excavated, sized and transferred to the conveyor.
8
CA 02610124 2014-08-25
In a further embodiment, a method is provided of extracting a body of oil sand
ore for conveyance to a mobile slurry facility, the method comprising:
locating the
mobile slurry facility near a mine face of a body of oil sand ore; positioning
a mobile
conveyor within operational reach of a section of the ore body and locating a
discharge end of the mobile conveyor to convey mined ore to the mobile slurry
facility; extracting the section of the ore body and conveying it to the
mobile slurry
facility; advancing the mobile conveyor generally about the discharge end to
locate
the mobile conveyor within operational reach of a further section of the ore
body;
extracting the further section of the ore body and conveying it to the mobile
slurry
facility; continuing to advance the conveyor and convey additional sections of
the ore
body to the mobile slurry facility until the ore within an arc sector about
the discharge
end of the conveyor has been extracted.
In a further embodiment, a method is provided of increasing the effective
length
of a mobile conveyor for conveying a mined ore, the method comprising:
(a) Locating a mobile conveyor within operational reach of a section of
ore;
(b) Extracting the section of ore within operational reach of the conveyor
and transferring the extracted ore to the conveyor;
(c) Advancing the conveyor generally about the discharge end to locate
the conveyor within operational reach of a further section of ore;
(d) Repeating steps (b) and (c) until substantially all ore within
operational
reach of the conveyor has been extracted. and,
(e) relocating the discharge end of the conveyor to a substantial center of
the arc.
In a further embodiment, a method is provided for increasing the mineable
volume of ore capable of being transported from the mine site to a discharge
point
using a mobile conveyor, the method comprising: Locating the mobile conveyor
near
a mine face with a discharge end located in communication with the discharge
point;
Excavating a section of ore within operational reach of the mobile conveyor
9
CA 02610124 2014-08-25
along the length of the conveyor, Repeatedly advancing the mobile conveyor
through
an operational arc generally about the discharge end to locate and extract
additional
sections of ore within operational reach along the length of the conveyor;
and,
Relocating the mobile conveyor to locate the discharge end in communication
with a
new discharge point located near the perimeter of the operational arc.
In a further embodiment, a process line is provided for excavating and
processing
oil sands ore near a mine face, the process line comprising:a mobile excavator
for
excavating ore along the length of a mobile mining conveyor; a mobile
comminutor for receiving and comminuting excavated ore and transferring
comminuted ore to the mobile mining conveyor; the mobile mining conveyor
conveying the comminuted ore to a transfer conveyor, the transfer conveyor
conveying the comminuted ore to a mobile slurry facility; the mobile slurry
facility
converting the comminuted ore into a slurry and pumping and conditioning the
slurry
through a hydro-transport pipeline to a mobile extraction facility; the mobile
extraction facility receiving the slurry and combining with a water stream to
separate
a bitumen stream and a tailings stream from the slurry; herein the bitumen
stream is
directed to a separation facility and the tailings stream is directed to a
tailings
treatment facility.
In a further embodiment, a process line is provided for excavating and
processing
oil sands ore near a mine face, the process line comprising: a mobile
excavator for
excavating ore along the length of a mobile mining conveyor; a mobile
comminutor
for receiving and comminuting the excavated ore and transferring the
comminuted ore
to the mobile mining conveyor; the mobile mining conveyor conveying the
comminuted ore to a transfer conveyor; the transfer conveyor conveying the
comminuted ore to a mobile slurry facility; at the mobile slurry facility
combining the
comminuted ore with process water to produce a slurry and pumping and
conditioning
the slurry through a hydro-transport pipeline to a mobile extraction facility
as a slurry
feed; at the mobile extraction facility receiving the slurry feed and
directing the slurry
feed and a water stream as inputs to a three stage countercurrent cyclone
separator;
the cyclone separator producing a bitumen rich stream and a tailings stream;
the
bitumen rich stream being directed to a froth concentration unit the froth
concentration unit separating the bitumen rich stream into a bitumen product
stream, a
CA 02610124 2014-08-25
recycled water stream and a fine tailings stream; the fine tailings stream
being
combined with the tailings stream to produce a tailings product stream; the
tailings
product stream being directed to a tailings treatment facility, the tailings
treatment
facility receiving the tailings product and combining the tailings product
with an
additive to produce a treated tailings stream; the treated tailings stream
being directed
to a tailings pond; the treated tailings stream being separated into a dry
tails phase and
a water phase; and, the water phase being collected at the tailings pond and
recycled
as industrial process water.
Figure 1 is an illustration of a process overview of one preferred embodiment.
The
aim of this embodiment is to provide a closed loop mining process that
minimizes the
transport tithe mineral component of the ore from the mine face and treats
the tails to
release the water component for reclamation as industrial process water. The
process
may be described as comprising the following main stages:
= excavating the ore 10;
= conveying the excavated ore to a slurry facility 12
= slurrying the comminuted ore 14;
= hydro-transporting the slurry to condition the slurry and transport it to
an
extraction facility 16;
= extracting from the slurry an enriched bitumen froth feed and a tailings
feed
18;
= treating the tailings feed with an additive 20;
= depositing the treated tailings feed at a deposition site 22; and,
= recycling the reclaimed water as industrial process water 24.
Figure 2 depicts the process line of one embodiment comprising a mobile
excavator 200 that excavates ore from a mine face 101 and transfers the
excavated ore
to a mobile comminutor 500. The mobile comminutor 500 comminutes the ore to
transportable size for delivery to a mobile mining conveyor 580. The mobile
mining
11
CA 02610124 2014-08-25
conveyor 580 delivers the crushed ore to a mobile slurry facility 800 where
the
crushed ore is converted into a slurry with the addition of hot process water
and
further comminuting and screening. Optionally process agents or conditioning
aids
may be added to the slurry at the mobile slurry facility 800. The slurry is
pumped
through a hydro-transport pipeline 850 to a mobile extraction facility 900
where the
bitumen is separated from the mineral component. The separated bitumen is
diverted
to a secondary extraction facility 1500 while the mineral component is
directed for
tailings treatment 1100 prior to being deposited at a tailings deposition site
1150.
Tailings treatment 1100 preferably comprises the addition of an additive to
the
tailings to assist in separation of the water component of the tailings from
the sand
and fines. The treated tailings are then deposited at tailings deposition site
1150. After
separation of the water from the solid component of the tailings, the water
may be
collected at the tailings deposition site and recycled as industrial process
water, either
back into the process, for instance to be used in the slurry and extraction
stages, or
else directed for other industrial process water uses.
The stages of the process will now be described in more detail.
Referring to figure 3, a top view of the excavation portion of one embodiment
is
shown. A mobile excavator 200, for instance a shovel, removes ore from the ore
body
100 at the mine face 101. The mobile excavator 200 transfers the ore to a
mobile
comminutor 500 before it is transported to the mobile slurry facility 800. The
ore is
deposited into the apron feed hopper 520 of the mobile comminutor 500 that
feeds an
apron feeder 530 to deliver the mined ore to primary comminuting rolls to
comminute, or crush, the ore down to transportable size. The apron feed hopper
520
serves the dual purpose of receiving the excavated ore and acting as a "dry"
surge or
inventory of excavated ore by receiving buckets of excavated ore and
delivering a
steady stream of excavated ore to the primary comminuting rolls. The
comminuted
ore falls onto the discharge conveyor 550 for conveyance from the mobile
comminutor 500 to a mobile mining conveyor hopper 570 for delivery to mobile
mining conveyor 580. The mobile mining conveyor 580 conveys the comminuted ore
to a transfer conveyor that delivers the ore to the mobile slurry facility
800.
12
CA 02610124 2014-08-25
Referring to figure 4, a side view of the excavation portion of the present
embodiment is
shown. The mobile excavator 200 is within close proximity of an ore body 100
and
within operational reach of a mine face 101. The mobile excavator 200
excavates ore
from the mine face 101. Prior to transport, the excavated ore must be sized
and
screened for reject material such as metal. The mobile excavator 200 directs
the
excavated ore to the mobile comminutor 500 which comminutes and screens the
ore.
Generally, the mobile comminutor 500 preferably includes tracks 510, an apron
feeder hopper 520, an apron feeder 530, primary comminuting rolls 540 and a
discharge conveyor 550. Cable reels 575 transported by the mobile mining
conveyor
hopper 570, supply power and communication cables to the excavator 200, and
mobile comminutor 500.
Figure 5 is an illustration of a preferred embodiment of a mobile comminutor
500
in accordance with the invention. The ore is initially deposited by the
excavator 200
into the apron feeder hopper 520 which directs the ore onto an apron feeder
530. The
apron feeder 530 conveys the ore to the primary comminuting rolls 540 which
comminutes the ore down to a conveyable size typically limiting ore pieces to
a
diameter of approximately less than about 350 mm. The apron feeder 530 and
primary comminuting rolls 540 also preferably includes at least two level
detectors.
The feeder level detector 532 is directed down the apron feeder 530 to detect
large
lumps of ore travelling up the apron feeder 530. When a large lump is
detected, the
feeder level detector 532 alerts the apron feeder 530 to slow down, to allow
the
material to be processed by the primary comminuting rolls 540. Similarly,
sizing level
detector 534 is directed across the primary comminuting rolls 540 to detect a
build-up
of material at the primary comminuting rolls 540. If the level of ore begins
to build up
above the primary comminuting rolls 540, the comminuting level detector 534
alerts
the apron feeder 530 to slow down the delivery of ore to allow time for the
primary
comminuting rolls 540 to process the built up ore. Preferably the speed of the
apron
feeder 530 is also controlled by a weight sensor located on the discharge
conveyor
550. By controlling the speed of the apron feeder 530 using the level
detectors and
weight sensor, a steady supply of transportable sized ore may be provided to
the
mobile mining conveyor 580. Optionally, heaters 522 may be provided at the
hoppers
13
CA 02610124 2007-11-09
and elsewhere as required to minimize build-up of ore when operating under
extreme
cold conditions.
The mobile comminutor 500 preferably includes tracks 510 to permit relocation
of the
mobile comminutor as the excavator 200 works the ore body. Figures 19a to 19c
illustrate an embodiment where the mobile comminutor 500 relocates each time
the
excavator 200 relocates to work a section of the ore 'body. As illustrated in
Figures
19a to 19c, the excavator 200 excavates all ore within its operational reach
at a
particular location, and then relocates closer to the newly exposed mine face
101. As
the excavator 200 relocates, the comminutor 500 and mobile mining conveyor
hopper
570 also relocate to pace the excavator 200. In the embodiment of Figures 19a
to 19c
the mobile comminutor 500 takes multiple short relocation steps at the same
time that
the excavator is relocating.
Figures 20a and 20b illustrate an alternate embodiment in which the excavator
200
excavates all ore within its operational reach at a particular location, and
then
relocates closer to the newly exposed mine face 101, but remaining within
operational
reach of the mobile comminutor 500. In this fashion, the excavator takes
multiple
relocation steps excavating about the mobile comminutor 500 location until all
ore
within operational reach of the mobile conuninutor 500 has been excavated.
Once the
ore has been excavated, both the mobile comminutor 500 relocates to a new
location
closer to the newly exposed mine face 101. In the embodiment of Figures 20a
and
20b, the mobile comminutor 500 takes less relocation steps to access all ore
within
operational reach of the mobile mining conveyor 580. The excavator 200 may,
however, take additional relocation steps or face some periods of down time
while
waiting for the mobile comminutor 500 to relocate closer to the newly exposed
mine
face 101.
Optionally the mobile conuninutor 500 includes supports 515 that are
preferably
lowered during operation while the excavator 200 is working a section of the
ore body
100 to stabilise the mobile comminutor 500. The supports 515 may preferably be
raised to permit the mobile comminutor 500 to relocate when the excavator 200
moves to a new section of the ore body 100. It will be appreciated that
supports 515
14
CA 02610124 2007-11-09
may be replaced by additional tracks 510, or dispensed with entirely,
depending upon
the weight distribution and stability of the mobile comminutor 500.
The sized ore is directed to a discharge conveyor 550 for delivery to the
mobile
mining conveyor 580. Ore that is too large, or too hard to be crushed in the
primary
comminuting rolls 540, is directed to a reject door and discharged out the
reject chute
to the ground below the mobile comminutor 500. Preferably the ore is also
screened at
the mobile comminutor 500 for metal contaminant, such as excavator teeth. As
will be
appreciated, other methods of screening the ore for metal and discarding metal
are
possible, such as screening the ore downstream after conveyance by the mobile
mining conveyor 580. Most preferably, however, the mobile comminutor 500
includes a metal detector 552 to examine the sized ore on the discharge
conveyor 550
for metal contaminants. If metal is detected by metal detector 552, the apron
feeder
530 and discharge conveyor 550 may be temporarily halted and a reject chute in
the
mobile mining conveyor hopper 570 may be aligned under the discharge point of
the
discharge conveyor 550. The discharge conveyor 550 then advances until the
metal is
discarded off the discharge conveyor 550 and into the reject chute. The
discharge
conveyor 550 is then temporarily halted again while the mobile mining conveyor
hopper 570 is re-aligned to direct discharged ore to the mobile mining
conveyor 580.
Referring to figure 6, the sized ore is first delivered to a mobile mining
conveyor
hopper 570 by the discharge conveyor 550. The mobile mining conveyor hopper
570
preferably traverses along rails or tracks that run the length of the mobile
mining
conveyor 580. As the excavator 200 advances along the mine face, the mobile
comminutor 500 follows the progress of the excavator. The mobile mining
conveyor
hopper 570 traverses along the transfer conveyor 580 to receive the crushed
ore from
the discharge conveyor 550 and deliver it to the mobile mining conveyor 580
for
conveyance. Preferably, the mobile mining conveyor hopper 570 conveniently
includes cable reels 575 to spool out power and communication cables to the
mobile
comminutor 500 and excavator 200 as they traverse along the mine face 101. In
this
manner, the power generation or transmission connection may be conveniently
located at the discharge end 590, of the mobile mining conveyor 580,
minimizing the
need to move such equipment. The mobile mining conveyor 580 also preferably
comprises crawler tracks 600 distributed along the length of the conveyor
which
CA 02610124 2007-11-09
enables the mobile mining conveyor 580 to advance laterally or to advance
about and
end of the mobile mining conveyor 580. Optionally, the mobile mining conveyor
580
may be accompanied by a fluid trailer 585 that supplies water or glycol to be
sprayed
on the transfer conveyor 580 belt to prevent material from sticking to the
belt in
extreme weather conditions.
In a preferred embodiment the mobile mining conveyor 580 is comprised of
multiple
conveyor sections that are connected together to create a chain of conveyor
sections
that collectively comprise the mobile mining conveyor 580. A continuous belt
is
supported by the sections to convey ore to the discharge end of the mobile
mining
conveyor 580. Preferably, each section includes at least one crawler track 600
to
reposition that section. More preferably the crawler tracks 600 are provided
with
independent height adjustable supports connecting the crawler tracks 600 to
the
mobile mining conveyor 580. In a preferred embodiment the sections are joined
by
pivot joints and an alignment gauge 585, such as string pots, is used to
determine
whether a section is inline with its adjacent sections. If the section is not
inline, the
section's crawler track 600 is repositioned until the section is inline and
horizontal. In
this way, the mobile mining conveyor 580 may be advanced generally about the
discharge end 590 by manually advancing the free end to a desired location.
With the
advancement of the free end crawler track, the adjacent section will no longer
be
inline with the end section. Upon detecting mislevel or misalignment, the
adjacent
section crawler track is also repositioned to maintain level alignment with
the end
section. Similarly, the next section in the chain detects a misalignment with
the
adjacent section and its crawler track is repositioned to maintain level
alignment. In
this way the mobile mining conveyor 580 may be advanced about the discharge
end
590 by manually advancing the free end crawler until it is in operational
proximity to
the current mine face 101. Alternatively the crawler tracks 600 may be
controlled by a
central motion controller to co-ordinate the advancement of all crawler tracks
600.
One advantage of employing a mobile mining conveyor 580, over a relocatable
conveyor, is that material that spills over the sides of the mobile conveyor
does not
significantly accumulate in a particular location. Depending upon the duration
of
operation the amount of spilled material that may accumulate around a
relocatable
16
CA 02610124 2007-11-09
conveyor may be considerable. By mining with a mobile mining conveyor 580, the
process avoids the need to clear spilled material prior to relocating the
conveyor.
Referring to Figures 7 and 8, at the discharge end 590 of the mobile mining
conveyor
580, the sized ore is deposited into a transfer conveyor hopper 610 that feeds
the sized
ore onto a transfer conveyor 620 that transports the material to the feed
chute of a
mobile slurry facility 800.
The mobile mining conveyor 580 conveys sized ore along its length to the
discharge
end 590. The discharge end 590 is in communication with a discharge point such
that
as sized ore is discharged off the discharge end 590, it continues in a
projectile motion
to the discharge point a short distance from the discharge end 590. In
operation the
mobile mining conveyor 580 is positioned such that the discharge point of the
mobile
mining conveyor is aligned with a target, in this case approximately the
center of the
transfer conveyor hopper 610. Preferably a location sensor is included to
assist in
locating the discharge point of the mobile mining conveyor 580 central to the
transfer
conveyor hopper 610, and maintaining its alignment with respect to transfer
conveyor
hopper 610, while advancing the mobile mining conveyor 580 about the discharge
end 590.
According to a preferred embodiment of the present invention, the mobile
mining
conveyor 580 consists of multiple independent sections. One of the advantages
of the
preferred embodiment is that each section may be individually powered and
operated
depending upon the location of the mobile mining conveyor hopper 570.
Similarly,
since each section is independently mobile, each section may be replaced as
necessary
if it breaks down while in service. Alternatively, a section may be removed
from the
mobile mining conveyor 580 and operation may continue, albeit with a mining
conveyor of shorter length. Preferably the conveyor belt is a continuous belt
as known
in the art. Conveyor sections may be added or removed by adding or removing
sections of the belt to accommodate the change in the length of the conveyor.
In a preferred embodiment the location sensor is optical sensor 595 located at
the
discharge end 590 that monitors the location of a positioning ring 605 located
around
the transfer conveyor hopper 610. As the mobile mining conveyor 580 is
advanced
17
CA 02610124 2007-11-09
about the transfer conveyor hopper 610, the optical sensor 595 monitors the
location
of the positioning ring 605 and provides feedback to control the advancement
of the
tracks 600 on the discharge conveyor section 597 so as to maintain the
discharge point
in the transfer conveyor hopper 610. Since the discharge end 590 is located
with
reference to the transfer conveyor hopper 610, the geometry of the transfer
conveyor
hopper 610 may effect the path through which the discharge end 590, and hence
the
mobile mining conveyor 580, may travel. For instance, the transfer conveyor
hopper
610 may be circular in which case the discharge end 590 will travel in a
generally
circular fashion. Alternatively, the transfer conveyor hopper 610 may be
elongate in
which case the discharge end 590 may travel in a generally arcuate fashion.
As described above, the mobile mining conveyor 580 conveys the sized ore off
the
discharge end 590 to a discharge point aligned with the transfer conveyor
hopper 610
of a transfer conveyor 620 for delivery to the mobile slurry facility 800
where it is
converted into a slurry and pumped into pipe-line 850 for transport to a de-
sanding
facility en route to a bitumen upgrader facility.. Since the mobile mining
conveyor
580 advances about the transfer conveyor hopper 610, the transfer conveyor 620
may
remain stationary throughout the execution of an operational arc. Preferably
the
transfer conveyor 620 is provided with a platform 630 on its underside for
engaging a
crawler when the transfer conveyor 620 is to be repositioned. In this
embodiment it is
unnecessary to include a motive drive on the transfer conveyor 620 since it
remains
stationary for extended periods of time.
Referring to figures 9a -9b, preparation of an ore body according to a
preferred
embodiment of the present invention is presented. Preferably, the ore body is
prepared
by initially excavating a "pocket" 55 into the mine face 101 with the
excavator 200
and mobile comminutor 500 to remove all of the ore within operational reach of
the
excavator 200 and mobile comminutor 500 while a discharge point off the
discharge
conveyor 550 is located outside the pocket 55 being excavated. The purpose of
excavating the pocket 55 is to permit location of the mobile slurry facility
800 as
close as possible to the mine face to facilitate removing the greatest
possible volume
of ore while the mobile slurry facility 800 remains in a single location.
While it is
possible to operate the excavator 200 and mobile comminutor 500 further into
the ore
body beyond the operational reach of the excavator 200 and mobile comminutor
500,
18
CA 02610124 2014-08-25
limiting excavation to their operational reach with the discharge point being
located
outside the pocket 55 minimises the need to employ additional equipment to
transport
the ore clear of the pocket 55.
As illustrated in figure 9c, after excavation of the initial pocket, the
mobile slurry
facility 800 and transfer conveyor 620 may be positioned such that the
transfer
conveyor hopper 610 is located in the pocket, thus locating the mobile slurry
facility
800 at an optimal location for removing a maximum volume of ore before having
to
move the mobile slurry facility 800. Optionally, as illustrated in figure 9c,
the
excavator 200 and mobile cornminutor 500 may continue to work the ore body to
enlarge the pocket 55 without the mobile mining conveyor 580 by locating a
discharge point off the discharge conveyor 550 in the apron feed hopper 610.
An
additional volume of the ore body is within operational reach of the excavator
200 and
mobile comminutor 500 when the discharge point is located in the transfer
conveyor
hopper 610 within the pocket 55. The advantage of excavating an enlarged
pocket by
delivering the ore directly from the mobile conuninutor 500 to the transfer
conveyor
hopper 610 is that it consumes less energy and results in less wear and tear
on
equipment. Optionally, the ore excavated during the initial pocket excavation,
illustrated in figures 9a-9b, may be fed into the mobile slurry facility 800
at this time
by depositing the ore in the transfer conveyor hopper 610. Alternatively, the
initially
excavated ore may be retained as a dry surge to feed to the mobile slurry
facility
during excavation down time such as excavator shovel repairs or conveyor
maintenance.
Referring to figures 10a -10e a top view schematic of one embodiment of the
process is presented. Figure 10a illustrates a close-up top view of a mining
cell
according to an embodiment of the present invention with the ore body 100 and
the
mobile mining conveyor 580 in an initial position. The excavator 200 removes
ore
from a mine face 101 and delivers it to a mobile comminutor 500 by depositing
it in
the apron feed hopper 520 to be directed to an apron feeder 530. The apron
feeder 530
carries the ore to primary comminuting rolls 540, not shown in this view, for
crushing
before the ore is directed to the discharge conveyor 550 to be transferred to
the mobile
mining conveyor hopper 570 to direct the ore to the mobile mining conveyor 580
for
delivery off the discharge end 590 of the mobile mining conveyor 580 to a
discharge
19
CA 02610124 2007-11-09
point. Preferably, the mobile mining conveyor 580 is oriented to position the
discharge point in a transfer conveyor hopper 610. Most preferably the mobile
mining
conveyor 580 positions the discharge point at or near the center of the
transfer
conveyor hopper 610. The transfer conveyor hopper 610 supplies the conveyable
ore
to a transfer conveyor 620 that delivers the ore to a mobile slurry facility
800. The
mobile slurry facility 800 adds HPW to convert the ore into a slurry that is
pumped
into a pipe-line 850 for hydro-transport.
Figure 10b illustrates the mining cell in a top view with the ore body 100 to
be
excavated and the excavator 200, mobile comminutor 500 and mobile mining
conveyor hopper 570 starting at an end of the mobile mining conveyor 580 and
removing ore within operational reach along the length of the mobile mining
conveyor 580.
Figure 10c illustrates the mining cell in a top view after all the ore within
operational
reach of the mobile mining conveyor 580 in the first position has been
excavated and
the conveyor has been advanced about the discharge end 590 to position a
further
section of ore within operational reach of the mobile mining conveyor 580
while
locating the discharge point in the transfer conveyor hopper 610. As
illustrated, once
the mobile mining conveyor 580 has been advanced, the excavator 200, mobile
comminutor 500 and mobile mining conveyor hopper 570 move along the mobile
conveyor 580 and excavate the ore within operational reach of the mobile
mining
conveyor 580. After all the ore within operational reach of the mobile mining
conveyor 580 has been excavated, the mobile mining conveyor 580 is again
advanced
about the discharge end.
Figure 10d illustrates the mining cell in a top view with the ore body 100 and
the
mobile mining conveyor 80 having been advanced to a further position and the
excavator 200, mobile comminutor 500 and mobile mining conveyor hopper 570
having completed excavating all the ore within operational reach of the mobile
mining
conveyor 580 in the further position.
Figure 10d illustrates the mining cell in a top view with the ore body 100 and
the
mobile mining conveyor 80 having been advanced to a further position and the
CA 02610124 2014-08-25
excavator 200, mobile comminator 500 and mobile mining conveyor hopper 570
having completed excavating all the ore within operational reach of the mobile
mining
conveyor 580 in the further position.
Figure 10e illustrates the mining cell in a top view with the ore body 100 and
mobile
mining conveyor 80 having been advanced through an operational arc about the
discharge end and the excavator 200 and mobile comminutor 500 having
excavated,
comminuted and transferred to the mobile mining conveyor hopper 570 an
operational
arc sector of ore.
Figure 10f illustrates the mining cell in a top view with the ore body 100
after the
excavator 200 and mobile comminutor 500 have prepared an initial pocket at the
perimeter of the excavated arc sector. The mobile slurry facility 800 has been
moved
from its prior location to be in close proximity to the mine face 101 with the
transfer
conveyor 620 located in the pocket. The excavator 200 and mobile comminutor
500
are initiating excavation of an enlarged pocket about the transfer conveyor
hopper
610. The mobile mining conveyor 580 has been positioned in close proximity to
the
mobile slurry facility 800 and transfer conveyor 620 to begin operation after
the
excavator 200 and mobile comminutor 500 have completed the enlarged pocket.
Figure 11 illustrates the mining cell in a top view with the ore body 100
after the
mobile mining conveyor 580 has been advanced through an operational arc sector
about a mobile slurry facility 800. In comparison to the embodiment
illustrated, a
conventional fixed conveyor 575 of similar length is illustrated with the
operational
reach of the conventional fixed conveyor 575 illustrated with cross-hatching
585. As
will be appreciated the effective length of the mobile mining conveyor 580 is
greater
than that of a conventional fixed conveyor 575 since a greater volume of ore
may be
excavated before relocating the mobile slurry facility 800 with a mobile
mining
conveyor 580 in this embodiment.
As described above, the discharge end 590 of the mobile mining conveyor hopper
580
delivers conveyable ore to the transfer conveyor hopper 610 of the transfer
conveyor
620. The transfer conveyor 620 supplies the conveyable ore to the mobile
slurry
facility 800. Since the mobile slurry facility 800 preferably utilises gravity
to assist in
21
CA 02610124 2007-11-09
slurrying the ore, the transfer conveyor 620 serves to elevate the conveyable
ore to the
height of the mobile slurry facility 800 ore input chute. The use of a
transfer conveyor
620 to offset the mobile slurry facility 800 from the discharge end 590 also
provides
the opportunity to increase the operational arc of the mobile mining conveyor
hopper
580. Furthermore, a single mobile slurry facility 800 may be used to process
ore from
multiple mobile mining conveyors 580. In such an embodiment, the transfer
conveyor
620 may be longer than the minimum length required for supplying conveyable
ore to
a mobile slurry facility 800 fed by a single mobile mining conveyor 580.
Figure 18a is an illustration of a mobile mining conveyor 580 combined with an
extended transfer conveyor 623 feeding the transfer conveyor 620. The
embodiment
of Figure 18a allows a mobile mining conveyor 580 to access a greater volume
of ore
before the mobile slurry facility 800 requires relocation. An additional
feature of
traversing the mobile mining conveyor 580 along the extended transfer conveyor
623
before rotating the mobile mining conveyor 580 about the distal end 623b of
the
extended transfer conveyor 623, is that it provides access to a section of ore
body
having straight sides. Among other uses, such an arrangement may be useful to
access
a volume of ore from a given mobile slurry facility 800 location when the ore
body is
of a relatively narrow width. The extended transfer conveyor 623 allows a
larger
volume of ore to be accessed than would otherwise be the case for the mobile
mining
conveyor 580 of a given length.
Figure 18b illustrates an embodiment where a single mobile slurry facility 800
may
be used to process ore from multiple mobile mining conveyors 580a, 580b. In
the
embodiment illustrated, two mobile mining conveyors 580a, 580b access adjacent
volumes of ore. Each of the discharge ends 590a, 590b pivot about a separate
discharge point for transferring ore to conveyors 625a, 625b that convey the
mined
ore to their discharge ends 592a, 592b to feed transfer conveyor 620. The
discharge
points may be fixed at a point along the conveyors 625a, 625b, as illustrated
in Figure
18b, or alternatively as illustrated in Figure 18f, mobile conveyor hoppers
may be
used to allow the discharge points to traverse along the conveyors 625a, 625b.
After
the mobile mining conveyors 580a, 580b have completed an arc sector as
suggested in
Figure 18b, one of the mobile mining conveyors 580a, 580b may be positioned to
pivot about a discharge end 592c located at the transfer conveyor 620 to
remove a
22
CA 02610124 2007-11-09
further section of ore between the arc sectors illustrated within reach of the
mobile
mining conveyors 580a, 580b. The embodiment of Figure 18b allows for a large
volume of ore to be processed with a single mobile slurry facility 800 at a
location,
increasing the time between moves for a given length of mobile mining
conveyors
580a, 5801). The embodiment may be implemented in a variety of methods,
including
operating both mobile mining conveyors 580a, 580b simultaneously, to feed
twice as
much ore to the mobile slurry facility 800, or alternately operating each
conveyor to
ensure a steady feed of ore, for instance when one conveyor is inoperative,
such as
when equipment is moving or a shift change occurs.
Figures 18c and 18d are plan view schematics, illustrating an embodiment where
multiple mobile mining conveyors 580, 581 are deployed in series. The
conveyors
580, 581 may be of similar length, or may comprise different lengths as is
convenient
for excavating a particular ore body 100. The excavator 200 and mobile
comminutor
500 work the ore body 100 feeding mobile mining conveyor hopper 571.The use of
multiple mobile mining conveyors 580, 581 allows for efficient mining of an
ore
body, including avoiding low yield volumes 105 (shown in plan views as an
area). As
illustrated in Figure 18c, the mobile mining conveyor 580 may be deployed as a
face
conveyor to allow mobile mining conveyor 581 to pivot about the mobile mining
conveyor hopper 570 to access ore around the low yield volume 105. Figure 18d
illustrates an embodiment where the mobile mining conveyor 580 is pivoting
about
the transfer conveyor 620, and the mobile mining conveyor 581 is pivoting
about the
mobile mining conveyor hopper 570. In an embodiment, mobile mining conveyor
581
may be advanced through all of the ore within operational reach of the mobile
mining
conveyor hopper 570 as it traverses along the mobile mining conveyor 580 which
is
held in a fixed position for the duration of the advancement. Alternatively,
the mobile
mining conveyors may both be advanced by pivoting about the transfer conveyor
620
providing an effective mobile conveyor length a length equivalent to the
combined
lengths the mobile mining conveyors 580, 581.
Figure 18e illustrates an embodiment where multiple mobile mining conveyors
580,
581 are deployed to excavate ore along mine wall limit 102. As illustrated,
the
conveyors 580, 581 may be of differing lengths as required to efficiently mine
the
wall limit 102.
23
CA 02610124 2014-08-25
Figure 18f illustrates an embodiment where multiple conveyors are working an
ore
body 100 around low yield sections 105. In the embodiment illustrated, the
mobile
mining conveyors 580a and 580b are of differing length to better work between
low
yield sections 105. Mobile conveyor hoppers 570 traverse along conveyors 625a,
625b to allow access to minable ore in the ore body 100 and avoid the low
yield
sections 105.
A mobile slurry facility 800 converts the conveyable ore delivered by the
transfer
conveyor 620 into a slurry for hydro-transport. In a preferred embodiment of
the
mobile slurry facility 800 the conveyable ore is first discharged from the
transfer
conveyor 620 into the roller screen feed chute 720. The roller screen feed
chute 720
feeds the roller screen 740 to crush the ore to a convenient size for
slurrying (typically
less than 65 mm in diameter) and allow the crushed and sized ore to fall
through the
screen. Oversize material that does not fall through the roller screen 740
passes to an
oversize comminutor 760 that crushes the lumps of oversize down to acceptable
size.
Hot Process Water (HPW) is typically introduced at the roller screen feed
chute 720
and additional HPW is added directly over the roller screen 740 and oversize
comminutor 760. The additional HPW assists in processing the ore,preventing
ore
buildup and defining the slurry density. The majority of the wet sized ore
passes
directly through the roller screen 740 for conversion to slurry in the slurry
pump box
780. The remaining oversize is wetted and crushed by the oversize comminutor
760
before falling into the slurry pump box 780 for conversion to slurry. While it
is
possible to provide for an overflow chute to discard oversize, it is
preferable to size
the roller screen 740 and oversize comminutor such that they are capable of
processing all of the ore supplied by the transfer conveyor 620.
Typically, HPW will be proportionately distributed approximately 70% at the
roller
screen feed chute 720, 20% at the roller screen 740 and 10% at the oversize
comminutor 760. Where the embodiment includes a metal detector and reject ore
discharge mechanism at the mobile comminutor 500, all of the ore received by
the
mobile slurry facility 800 may be processed using the roller screen 740 and
oversize
conuninutor 760. While it is possible to detect metal in the ore at the roller
screen
740, it is preferable to discard reject material as soon as possible in the
process.
Furthermore, it is preferable to discard reject material prior to processing
by the
24
CA 02610124 2014-08-25
primary comminuting rolls 540. One advantage of the combination of the mobile
comminutor 500 and mobile slurry facility 800 of this embodiment is that
reject
material is discarded near the location of excavation. As the excavator 200
works an
ore body, detected reject material will be discarded near the location of its
excavation.
Not only does this avoid transporting reject material along the mobile mining
conveyor 580 where it can damage equipment but it eliminates the need for
reject
material handling equipment at the mobile slurry facility 800 where it would
be much
more difficult to incorporate such equipment.
The sized ore and HPW falls into the slurry pump box 780 that is sized for a
slurry
retention time of approximately one minute. The slurry pump box 780 supplies
the
hydro-transport pump 820 with slurry. A one minute retention time is the
preferred
minimum to provide a wet surge capability to continuously supply slurry to the
pump.
When the level of slurry falls below a low level, Cold Process Water (CPW) may
be
added to maintain the level in the slurry pump box and ensure the hydro-
transport
pump 820 does not cavitate. As required, HPW may be added along with CPW to
maintain a working temperature under cold conditions.
Emergency ponds are preferably located near the mobile slurry facility 800 to
allow
dumping of slurry from the mobile slurry facility 800 or the pipeline 850
under
emergency conditions. The size of the emergency ponds is preferably large
enough to
accommodate the directed drainage of the contained volume of any one of the
following: a drainable section of hydro-transport pipeline (24"), a drainable
section of
HPW pipeline (24"), a drainable section of CPW pipeline (20"), or the volume
of the
slurry pump box 780. The size of the drainable sections of the pipelines are
site
specific due to logistical and geographical features. The emergency pond is
preferably serviced by a submersible pump which is able to return the pond
fluids
back to the process through the slurry pump box at the end of the emergency.
The slurry is pumped through the hydro-transport pipeline 850 to an extraction
facility. As mentioned above, in addition to transporting the slurry, the
hydro-
transport process serves the secondary purpose of conditioning the slurry. The
length
of hydro-transport required to condition the slurry depends on several factors
including the grade of ore, temperature of the ore, temperature of the process
water
CA 02610124 2007-11-09
and the size of ore being delivered to the slurry pump box. Typically, to be
fully
conditioned the slurry requires at minimal distance of one kilometre of hydro-
transport distance.
Preferably the extraction facility is a mobile extraction facility 900 that
receives as
inputs the conditioned slurry as an ore slurry feed 1200 and process water
1205, and
produces as outputs an enriched bitumen stream 1400 and a tailings stream
1450. In a
preferred embodiment, the mobile extraction facility 900 comprises separate
portable
modules that may be transported to a location separately and then connected
together
in series to provide a single extraction facility. Preferably the mobile
extraction
facility 900 comprises a primary separation facility connected to a froth
concentration
facility. More preferably, the primary separation facility comprises two or
more
separate separation cyclone modules that are combinable in situ to comprise
the
primary separation facility. Most preferably, the primary separation facility
comprises
three separate separation cyclone modules connected in series in a
countercurrent
configuration. The use of separate modules allows for ease of portability and
allows
the process to be flexible to tailor the extraction facility to the ore body
being
excavated. For instance, a high grade ore body that contains very little fine
solids/mineral component may not require the rigor of a three cyclone circuit,
and in
such a case the extraction facility may comprise only one or two of the
modules.
Generally, to accommodate all ore types, a three cyclone system is preferred.
The
modules preferably comprise transportable platforms, such as skids, that may
be
transported by crawlers or other motive modules. Alternatively, the modules
may be
provided with driven tracks.
In an alternate embodiment, the mobile extraction facility 900 comprises a
single
facility, containing all separation vessels and primary froth concentration
equipment.
Use of a three stage cyclonic system is further advantageous in a mobile
extraction
system for several reasons. First, the size of each individual cyclone stage
may be
reduced since a three stage counter- current process results in a separation
efficiency
either equivalent to, or better than, current extraction methods. Second, each
of the
three cyclones may be transported separately, greatly improving the ease of
relocating
the extraction facility. Third, the use of a three stage countercurrent
cyclonic system
26
CA 02610124 2014-08-25
allows a mobile extraction facility to operate with a variety of ore grades.
Fourth, as
mentioned above, the number of stages may be tailored to match the separation
efficiency with the grade of ore being processed.
As described above, the slurry that is fed to mobile extraction facility 900
is generally
formed using HPW. In conventional bitumen extraction equipment such as primary
separation vessels (PSV), where bubble attachment and flotation are used for
bitumen
extraction, temperature can affect the efficiency of the extraction process.
In the
preferred extraction embodiments described above, the extraction process is
not as
temperature sensitive since the cyclone equipment provides solid/liquid
separation
based on rotational effects and gravity. Extraction efficiency tends to be
maintained
even as temperature drops making the cyclone extraction process more amendable
to
lower temperature extraction. This has energy saving implications at the
mobile
extraction facility 900 where water feed 1305 or recycled water stream 1370 do
not
have to be heated to the same extent as would otherwise be necessary to
maintain a
higher process temperature.
Preferably each of the cyclone separation modules are self-contained and
include a
cyclone, as well as associated connections, pump boxes, and pumps. This way,
if one
unit has a mechanical failure, the extraction facility may be brought back
online by
simply replacing the faulty cyclone separation unit. Preferably the cyclone
separation
modules are connected in series in a countercurrent configuration in which the
water
stream and slurry stream enter at opposite ends of the three cyclone
combination.
Thus, for example, water entering the process (either make-up, recycled, or
both) is
first contacted with a bitumen-lean feed at the last cyclone separation unit
in the
series. The cyclonic separation units are preferably vertical cyclones, which
have a
reduced footprint. Suitable cyclonic separation vessels include those
manufactured by
Krebs Engineers (www.krebs.com) under the trade-mark gMAX.
This modular arrangement of the extraction system provides for both mobility
of the
system and flexibility in efficiently handling of different volumes ofi ore
slurry. For
example, as illustrated in Figure 17, a preferred setup according to an
embodiment of the
invention in which each cyclone separation stage 106, 108 and 110 is mounted
on its
own independent skid 160 to form a mobile module. Positioned between each
27
CA 02610124 2007-11-09
cyclone separation stage skid 160 is a separate pump skid 162 which provides
appropriate pumping power and lines to move the froth streams and solid
tailings
streams between the cyclone separation stages. It is also possible that any
pumping
equipment or other ancillary equipment can be accommodated on skid 160 with
the
cyclone separation stage. In the illustrated arrangement of Figure 17, groups
of three
mobile modules are combinable together to form cyclone separation facilities
102,
102', 102" to 102" as needed. Also associated with each cyclone separation
facility is
a mobile froth concentration facility 130 mobile modules comprising skids or
other
movable platforms with appropriate cyclone stage or froth concentration
equipment
on board may be assembled as needed to create additional mobile extraction
systems
200', 200" to 200n to deal with increasing ore slurry flows provided by hydro-
transport line 850. Ore slurry from the transport line 850 is fed to a
manifold 103
which distributes the slurry to a series of master control valves 165. Control
valves
165 control the flow of ore slurry to each mobile extraction system 200 to
20011. This
arrangement also permits extraction systems to be readily taken off-line for
maintenance by switching flow temporarily to other systems.
According to a preferred embodiment, the cyclone separation units 1210, 1220,
1230
are connected as illustrated in figure 12. The slurry is delivered by the
hydro-transport
pipeline 850 as an ore slurry feed 1200 to the first cyclone separation unit
1210. The
first cyclone 1210 separates the ore slurry feed 1200 into a first bitumen
froth stream
1300 and first tailings stream 1310. The first tailings stream 1310 is pumped
to a feed
stream of a second cyclone 1220. The second cyclone 1220 produces a second
bitumen froth stream 1320 and a second tailings stream 1330. The second
bitumen
froth stream 1320 is combined with the ore slurry feed 1200 as the feed stream
of the
first cyclone 1210. The second tailings stream 1330 is combined with a water
feed
1305 as the feed stream of a third cyclone 1230. The third cyclone 1230
produces a
third bitumen froth stream 1340 and a third tailings stream 1350. The third
bitumen
froth stream 1340 is combined with the first tailings stream 1310 as the feed
stream of
the second cyclone 1220. The third tailings stream 1350 from the third cyclone
1230
forms a tailings stream 1400 that is pumped to a tailings treatment facility
1100.
Optionally a "scalping" unit 1205, such as a pump box or the like, may be
included on
the ore slurry feed 1200 to remove any froth formed in the slurry feed 1200
during the
28
CA 02610124 2007-11-09
hydro-transport process and divert the bitumen froth directly to be combined
with the
first bitumen froth stream 1300. Removal of the bitumen rich froth at the
scalping unit
1205 assists in further increasing the recovery efficiency of the primary
separation
facility. Preferably, as indicated, the scalping unit 1205 is located upstream
of the
infeed of the second bitumen froth stream 1320.
The first bitumen froth stream 1300 is directed to a froth concentration
facility to
reduce the water content, remove remaining fines, and produce an enriched
bitumen
product stream 1400. Preferably, the froth concentration facility is located
proximate
to the primary separation facility. Most preferably, the froth concentration
facility
comprises a separate portable unit that may be combined with the primary
separation
facility units to comprise the mobile extraction facility 900. Typically the
froth
concentration facility comprises at least a froth concentration vessel 1240,
such as a
flotation column, a horizontal decanter, an inclined plate separator, or other
similar
device or system known to be effective at concentrating bitumen froth. In
addition to
the first bitumen froth feed, an air feed 1355 or chemical additive stream may
also be
introduced into the froth concentration vessel 1240. Optionally the froth
concentration
facility may comprise a combination of effective devices. In a preferred
embodiment,
as illustrated in figure 12, the froth concentration vessel 1240 comprises a
flotation
column. In a further preferred embodiment for a mobile extraction facility a
horizontal decanter is used to separate an enriched bitumen stream from the
first
bitumen froth stream. The selection of a series of countercurrent cyclone
separators
results in a compact separation facility that remains able to remove the
majority of the
mineral component from the ore slurry feed 1200. The low solids content of the
first
bitumen froth stream permits the use of a horizontal decantor as the froth
concentration vessel with a low risk of plugging due to sedimentation. Use of
a
horizontal decantor is desirable due to its small footprint, thus allowing for
the
potential of the vessel being made movable, and still result in a robust
extraction
facility that has a low propensity of being fouled with silt or other mineral
component.
Within the froth concentration vessel 1240, the froth is concentrated
resulting in an
enriched bitumen froth product stream 1400, that may optionally be transported
to a
secondary separation facility (not shown) to increase the hydrocarbon
concentration in
the froth before being pumped to an upgrader facility. Typically, the
secondary
29
CA 02610124 2014-08-25
separation facility will be a larger, more permanent facility. One advantage
of the
process of some embodiments is that an enriched bitumen froth stream 1400 is
produced relatively close to the excavation site, greatly reducing the current
requirement to transport large volumes of water and mineral component to the
permanent separation facility.
Froth concentration vessel 1240 also produces a fine tailings stream 1360 that
comprises water and fine solids contained in the first bitumen froth stream
1300. In
one embodiment, any known chemical additives may also be used in the froth
concentration facility to enhance the separation of fines from the water.
Preferably the fine tailings stream 1360 is diverted to a water recovery unit
1250,
which separates the fine tailings stream 1360 into a recycled water stream
1370 and a
fine tailings stream 1380. In a preferred embodiment, the water recovery unit
1250 is
a hydrocyclone to separate small sized particulate since the majority of the
mineral
component is removed by the primary separation facility. The fine tailings
stream
1380 is preferably combined with the third tailings stream 1350 to produce a
tailings
stream 1450 from the mobile extraction facility 900, The recycled water stream
1370
is preferably combined with the water feed 1305 for input to the third
cyclone. As
necessary, the recycled water stream 1370 may also be combined with the third
tailings stream 1350, fine tailings stream 1380 or tailings stream 1450 as
necessary to
control the water content of the streams. Preferably density meters (not
shown)
monitor the streams to determine whether, and how much, recycled water 1370
should
be added. The addition of water to the third tailings stream 1350 and tailings
stream
1450 may be necessary to maintain a pumpable stream, as the primary separation
facility removes most of the water from the third tailings stream 1350 and
fine tailings
stream 1380. The water recovery unit 1250 provides significant efficiencies in
that the
process water used in the mobile extraction facility 900 is preferably heated.
The
recycled water stream 1370 is typically warm or hot, so that reintroducing the
recycled water stream 1370 reduces the heat lost in the extraction process.
An advantage of this preferred embodiment of the present invention is that
water may
be recycled in the extraction process, and the mobile extraction facility 900
produces
a single tailings stream 1450.
CA 02610124 2007-11-09
In a further optional embodiment, the ore slurry feed 1200 may be provided
with any
number of known additives such as frothing agents and the like prior to being
fed to
the primary separation facility to prepare the ore slurry feed 1200 for
extraction. An
example of such additives would be caustic soda, geosol, or other additives as
described in U.S. Patent No. 5,316,664.
As mentioned above, the tailings stream 1450 is pumped to a tailings treatment
facility 1100. The tailings treatment facility 1100 may be located at the
mobile
extraction facility 900, or some distance from the mobile extraction facility
900
depending upon the availability of a tailings deposition site 1150. As will be
appreciated, the location of the tailings deposition site 1150 is preferably
close to the
mobile extraction facility 900 to minimize the distance the tailings stream
1450 must
be transported. However, the tailings treatment facility 1100 may be located
distant
from the mobile extraction facility 900 if it is necessary to locate the
tailings
deposition site 1150 at a distant location.
While the tailings treatment facility 1100 may comprise a known method or
process
of handling tailings, preferably tailings treatment facility 1100 comprises
the addition
of a rheology modifier or other such additive to the tailings stream 1450
prior to
deposition at the tailings deposition site. An example of a suitable additive
is
described in PCT publication WO/2004/969819 to Ciba Specialty Chemicals Water
Treatment Limited.
In a further preferred embodiment, the third tailings stream 1350 and fine
tailings
stream 1380 are mixed to ensure a homogenous distribution of coarse and fine
particulate in the tailings stream 1450. A preferred additive is a rheology
modifier
additive such as a water soluble polymer that may be added and mixed with the
tailings stream 1450 to produce a treated tailings stream. The additive may be
mixed
into the tailings stream 1450 either during a pumping stage, or subsequently
added in
liquid form near the tailings deposition site. Preferably the treated tailings
are
deposited at the tailings deposition site and allowed to stand and rigidify
thereby
forming a stack of rigidified material. The addition of the additive results
in a whole
dry tails that rigidifies relatively quickly to produce a relatively
homogenous tailings
deposition. After application of the additive, the water separates from the
mineral
31
CA 02610124 2014-08-25
component free from the fines. Unlike conventional tailings ponds, after
addition of
the additive the treated tailings produced according to the present embodiment
release
water that is sufficiently clear to be recycled as industrial process water
almost
immediately after tailings deposition. Furthermore, the recycled industrial
process
water is often still warm, reducing the energy required to be added to produce
hot
process water. The industrial process water may be recycled back into the
mobile
extraction facility 900, the mobile slurry facility 800 or other industrial
processes as
required. Furthermore, after separation of the water, the mineral component is
comprised of both sand and fines, and is thus more stable than typical
tailings
produced by known processes. This provides the unique opportunity to reclaim
the
solid tailings relatively soon after excavation.
A suitable mobile slurry facility may comprise the slurry apparatus 10
illustrated in
figures 13 to 16 and further described in applicant's co-pending application
METHOD AND APPARATUS FOR CREATING A SLURRY, filed November 9,
2006 and claiming priority from CA2,526,336.
As shown in figure 13, the slurry apparatus 10 provides a frame 20 having a
base 22.
The frame 20 may optionally also be provided with sides 24. The frame 20 is
preferably formed from steel girders or I-beams having the required load-
bearing
capacity, welded, bolted, or otherwise suitably affixed together. The frame
supports a
slurry box 30, which may be a conventional slurry box constructed to support
the
desired slurry load. The slurry box 30 essentially acts as a wet surge,
maintaining the
required constant supply of slurry to the slurry pump 39. The slurry box 30
provides a
slurry outlet 38 which feeds the slurry pump 39, and the slurry pump 39 in
turn
provides a slurry outlet 41 to which a hydrotransport conduit (not shown) is
detachably coupled by suitable means, for example a bolted flange.
An ore size regulating apparatus such as a screen or comminuting apparatus 50
is
suspended above the slurry box 30. For example, in the preferred embodiment
the
comminuting apparatus may be a screening/sizing roller screen such as that
described
in Canadian Patent Application No. 2,476,194 entitled "SIZING ROLLER SCREEN
ORE PROCESSING" published January 30, 2006, which is incorporated herein by
reference, which both screens and crushes ore. In the preferred embodiment the
32
CA 02610124 2014-08-25
comminuting apparatus 50 is supported on the frame 20 of the slurry apparatus
10,
with the output face of the comminuting apparatus 50 in communication with the
open top of the slurry box 30 such that comminuted ore fed to the comminuting
apparatus 50 is directed into the slurry box 30 under the force of gravity.
Alternatively, as screen may be provided to screen the incoming ore flow as an
initial
step before crushing.
Because the slurry apparatus 10 in this embodiment is moveable, it is
advantageous to maintain a low centre of gravity in the slurry apparatus 10
and
therefore if the comminuting apparatus 50 is suspended above the slurry box 30
it is
advantageous to provide the comminuting apparatus 50 as close as possible
(vertically) to the open top of the slurry box 30. The comminuting apparatus
50 may
be oriented close to the horizontal, or alternatively may have either a
positive or
negative angle to the horizontal. In a preferred embodiment the comminuting
apparatus 50 is oriented at an angle to the horizontal such that comminuted
ore is fed
at the higher end of the comminuting apparatus 50. The comminuting apparatus
50
may be supported on its own separate frame, may be solely supported by a side
24 of
the slurry apparatus frame 20, or may be supported on the slurry box 30.
Alternatively, the comminuting apparatus 50 may be in communication with the
slurry box 30 via one or more interposed conveyor mechanisms, such as a
transfer
conveyor (not shown).
The comminuting apparatus 50 may alternatively be housed in a separate
structure
and maintained in communication with the slurry box 30 by a conveying
apparatus
such as a transfer conveyor (not shown). Similarly, while the illustrated
embodiment
shows the slurry pump 39 and electrical transformers 9 housed in the structure
of the
slurry facility 10, it is possible to house these components in one or more
separate
structures that are detachably connected to the relevant systems in the slurry
facility
10 when the slurry facility 10 is in operating mode. It is advantageous to
provide
transformers 9 within or immediately adjacent to the slurry facility 10, which
will
gradually be moved away from any permanent transformer substation as mining
progresses.
33
CA 02610124 2007-11-09
A water supply 60, for example a hood with a spray header (shown in Figure
14), is
positioned to apply hot process water to the ore as it is fed into the
comminuting
apparatus 50, assisting in the comminuting process and so that ore is already
wetted
when it enters slurry box 30. As is well known in the art, the hot process
water is
mixed with the ore in a proportion which provides the desired slurry
consistency for
conditioning during transport to an extraction facility. The water supply 60
may be
provided in any convenient location for dispensing the process water over the
ore,
preferably before comminution or optionally after comminution.
The slurry box 30 is mounted to the floor 22 of the slurry apparatus frame 20
in the
desired position. As illustrated in Figure 14, the frame 20 is supported on a
first set of
spaced apart support points 21, for example adjacent to the corners where the
sides 24
meet the base 22, which may be mounted on crane mats 23 as in the embodiment
illustrated in Figures 13 and 14, to support the frame 20 in stationary mode,
or
alternatively may be mounted on pontoons 27 or other suitable support. The
slurry
box 30 may be disposed anywhere within the frame 20, as long as the centre of
gravity CG I of the slurry apparatus 10 when the slurry box 30 is filled is
within the
area bounded by the first set of spaced apart support points 21 (as shown in
Figure
14).
The frame 20 further contains other apparatus incidental to the operation of
the slurry
facility, which may for example include a gland water supply for the slurry
pump 39,
cooling units for conditioning the air within the facility to make it suitable
for
workers, electrical transformers for powering the equipment used in the slurry
facility
10, safety equipment, overhead cranes for maintenance and so on. The
distribution of
equipment about the frame 20 of the slurry apparatus 10 determines a first
center of
gravity CG1 for the slurry apparatus 10 in a stationary mode, in which the
slurry box
is filled and operational. Preferably the amount and size of equipment are
minimized to keep the weight of the facility 10 as low as possible; for
example, the
facility 10 may house a single hydrotransport pump 39 (or the hydrotransport
pump
39 may be supported on a separate structure as noted above). The heaviest
equipment
30 should be as low as possible within the frame 20, to keep the centre of
gravity CG1
and CG2 low. In the stationary mode, when the frame 20 is supported on the
first set
of spaced apart support points 21 and the slurry box 30 is filled with slurry
and
34
CA 02610124 2007-11-09
operational, a considerable additional amount of weight is concentrated in the
region
of the slurry box 30, which determines the position of the first center of
gravity CGI.
The frame 20 thus supports all the on-board equipment, plus the weight of the
slurry,
on the first set of spaced apart support points 21.
In a moving mode, with the slurry box 30 empty, the centre of gravity is
disposed at
CO2. The base 22 of the frame 20 is provided with a lifting region 70, shown
in
Figure 15, which is formed by a series of beams affixed to the main girders 28
of the
base 22. The entire slurry apparatus 10 can thus be lifted by a single moving
device
such as a mobile crawler 80, for example that produced by Lampson
International
LLC (hereinafter referred to as a "Lampson Crawler"), lifting solely at the
lifting
region 70, without substantial deformation of the frame 20. The lifting region
70
defines a second set of spaced apart support points 72, which is directly
beneath (and
preferably centered under) the second center of gravity CO2. The Lampson
Crawler,
which is essentially a hydraulic lifting platform having a propulsion system
and
mounted on tracks as illustrated in Figure 9B, can be positioned under the
lifting
region 70 using locator tabs 74, shown in Figure 15, and raised to lift the
frame 20
while maintaining the stability of the facility 10.
In the operating mode, ore is fed to the comminuting apparatus 50 in any
desired
fashion, for example via a transfer conveyor 6 as shown in Figures 13 and 4.
Preferably the transfer conveyor 6 is freestanding and not connected to the
slurry
apparatus 10, but suspended in communication with the slurry apparatus 10. The
ore
is processed by the comminuting apparatus 50, preferably to reduce the
particle size
of the entire inflow of ore to a maximum of 2" to 2Y2" (although larger ore
sizes can
also be processed). The comminuting apparatus 50 may include an oversize
conuninuting component 52 (shown in Figure 14) to comminute oversized ore and
eliminate rejected ore.
The comminuted ore is mixed with water from the water supply 60 and fed into
the
slurry box 30. A slurry of the consistency desired for hydrotransport is thus
created
within the slurry box 30. The slurry progresses through the slurry box 30 over
the
selected retention interval and egresses through the slurry outlet to a
hydrotransport
pump 39, which in turn feeds the slurry into a hydrotransport outlet 41 to
which a line
CA 02610124 2007-11-09
(not shown) is detachably connected for transport to an extraction facility
(not
shown). The hydrotransport line is detachable from the hydro transport outlet
41 to
allow for periodic movement of the slurry apparatus 10 to a new site as the
mine face
moves away from the slurry apparatus 10.
The electrical supplies including all power lines (and optionally
telecommunications
cables) are preferably contained in a power cable that detachably connects to
a local
connection (not shown) on the slurry facility 10, which may for example be
adjacent
to the transformers 9, to facilitate easy connection and disconnection of all
electrical
systems to a standard power source remote to the movable facility 10.
Preferably the
electrical power system is grounded via cable to a local transformer station
or
platform, rather than directly into the ground, either via the power cable or
via a
separate grounding cable, to facilitate detachment and reattachment of the
ground
connection during the relocation procedure. Similarly, water supplies and
connections
to fluid outlets (for example emergency pond outlet 45) are not welded but are
instead
detachably coupled via bolted flanges, quick-connect couplings or other
suitable
detachable connections as desired to facilitate detachment and reattachment
during the
relocation procedure.
When it is desired to move the slurry apparatus 10 to a new location, the
transfer
conveyor 6 is deactivated to discontinue the ore flow, and the slurry box 30
is empty
and flushed. Preferably the slurry apparatus 10 includes a cold water supply
43 for use
in flushing the slurry apparatus (and in case of emergency; an emergency
outlet 45 is
also preferably provided for directing contaminated water to a nearby
emergency
pond if needed). When the slurry box 30 has been completely emptied and
flushed,
the hydrotransport line (not shown) is disconnected from hydrotransport pump
39.
All electrical and water supplies are disconnected from the apparatus 10. Once
all
water supplies and electrical supplies have been disconnected, the slurry
apparatus 10
is ready to be moved to a new location.
A path to the new location is prepared, for example by compacting and laying
down a
suitable bed of gravel, if necessary. The new location is surveyed to ensure
it is level
(using gravel if necessary to level the site), and in the embodiment
illustrated in
36
CA 02610124 2007-11-09
Figures 13 and 14 crane mats are laid optionally covered by metal sheeting
(not
shown) to avoid point-loading the crane mats 23. In this embodiment hydraulic
jacks
29 are provided generally under the first set of spaced apart support points,
supported
on the crane mats 23. The jacks 29 are actuated, either in unison or
individually in
increments, to raise the frame 20 to a height that will allow a moving device
80 such
as a Lampson Crawler, with its hydraulic platform 82 in retracted mode, to be
driven
beneath the base 22 of the frame 20 and positioned under the lifting region 70
using
locator tabs 74 (shown in Figure 15) as a guide to position the hydraulic
platform 82.
The hydraulic platform 82 is raised, lifting the entire frame 20. When the
frame 20
has been raised to support the frame the hydraulic jacks 29 are retracted (as
shown in
Figure 16), the propulsion system in the Lampson Crawler 80 is engaged and the
slurry apparatus 10 is moved toward the new location. Preferably the slurry
apparatus
10 comprises on-board levels (not shown) at locations visible from the
exterior of the
apparatus 10, and/or a water level comprising a flexible tube filled with
water and
extending across the entire frame 20 (not shown), which are carefully
monitored by
operators to ensure that the facility 10 remains level within the tolerances
permitted
by the second set of spaced apart support points 72 (as described below).
As illustrated in Figure 16 the slurry apparatus 10 may be tilted, preferably
up to or
potentially more than 8 from the vertical, while maintaining the center of
gravity in
moving mode CG2 over the lifting region 70. This allows the slurry apparatus
10 to
be moved up or down a grade, and to tolerate variations of the ground surface.
The
hydraulic lifting platform 82 on the Lampson Crawler also has the ability to
lift
differentially, and thus compensate to some extent for the angle of a grade as
shown
in Figure 16. However, the slurry apparatus 10 itself may be tilted up to the
point
where the center of gravity CG2 reaches the periphery of the lifting region
70, beyond
which the apparatus 10 will become unstable.
When the new site is reached the hydraulic jacks 29 are extended to support
the frame
on the crane mats 23 which have been placed on the ground beneath the first
set of
support points 21, the hydraulic lifting platform 82 is lowered and the
Lampson
Crawler is driven away from the site. The slurry facility 10 is fully
supported by the
first set of spaced apart support points 21, and can be returned to the
operating mode
by extending (from the previous site) and reconnecting the hydrotransport line
and all
37
CA 02610124 2014-08-25
electrical and water supplies. An ore feeder such as a transfer conveyor is
positioned
in communication with the comminuting apparatus 50, and operation of the
slurry
facility 10 is resumed. When the slurry box 30 is once again filled with
slurry, the
center of gravity will shift from CO2 back to CGI, shown in Figure 14.
In a further embodiment of the apparatus, the frame 20 is provided with
pontoons 27
onto which the frame 20 is set instead of crane mats 23. This reduces the
steps
required to both lift the slurry apparatus 10 and to prepare the new
relocation site.
This also has the advantage of adding weight to the bottom of the frame 20,
lowering
the centres of gravity CG I and CO2. The operation of this embodiment is
otherwise
as previously described.
A suitable system, apparatus and process for extraction is described and
claimed in
applicant's co-pending application entitled SYSTEM, APPARATUS AND PROCESS
FOR EXTRACTION OF BITUMEN FROM OIL SANDS, filed November 9, 2006
and claiming priority from CA2,526,336.
Illustrative embodiments of the invention having been thus described by way of
example only, it will be appreciated that variations and permutations may be
made
without departing from the invention, as set out in the appended claims. All
such
variations and permutations are intended to be included within the scope of
the
invention.
38
