CA3089104A1 - A commercial oleophilic sieve separator - Google Patents

Abstract

The present patent describes large relatively cold rotating cages covered by oleophilic sieve and immersed in an effluent tank to quickly and efficiently separate oil sand slurry, tailings pond fluid fine tailings or a mixture of both. It also is suitable for commercial use to separate mineral mine or marine deposit and water slurries that contain oleophilic and hydrophilic particulates, adding for mine minerals separation feed a viscous liquid oleophilic scavenger to cause adhesion to oleophilic sieve of oleophilic minerals. The sieve and viscous oleophilic phase with minerals adhering to sieve surfaces passes through a hot zone to yield from the sieve good quality warm or hot oleophilic liquid product containing potentially valuable oleophilic mineral particulates.

Description

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Jan Kruyer, P.Eng., Thorsby, AB., CA.
A COMME .CIAL OLEOPHILIC SIEVE SEPARATOR
FIELD OF THE INVENTION
The present application relates generally to devices and methods for separating water and hydrophilic particulate mineral matter from viscous hydrocarbon (e.g. bitumen) and oleophilic particulate mineral matter. More particularly, the present invention relates to apparatus and method for very fast phase separation of a fluid mixture of oleophilic phase and hydrophilic phase using oleophilic sieve(s). Accordingly, the present invention involves the fields of process engineering, chemistry and chemical engineering.
PRIORITY
This patent application claims priority to Canadian patent 2,999,466 "AN
OLEOPHILIC SIEVE SEPARATION APPARATUS" of the same inventor, which is included here by reference. This prior filed patent application had several deficiencies which are overcome in the present patent to improve process performance. In the present patent, herein described and claimed, the separation apparatus is immersed in an effluent tank and oleophilic rods in rotating cage are elevated by and spilled from bench or benches inside the rotating cage of the present patent to transfer oleophilic phase from feed inside the cage to settling oleophilic rods for subsequent transfer to oleophilic sieve surfaces. The oleophilic phase covered sieve surfaces pass through a hot zone where heat causes oleophilic phase to leave sieve surfaces as fluid product. In the above referenced prior patent, oleophilic rods were not elevated by bench but revolved due to rotation of the cage inside the rotating cage which, unlike the present patent application, was not immersed in an effluent tank. As a result, the present invention is superior in separating oleophilic phase from hydrophilic phase.
BACKGROUND OF THE INVENTION
The present patent application relates to devices and methods for very fast continuous feed separation of viscous hydrocarbon and oleophilic particulates from water and from hydrophilic particulates inside a cage. More particularly, the present invention relates to oleophilic sieve(s) surrounding a rotating cage partly immersed in effluent in a tank at a temperature preferably below 40 degrees centigrade. Oleophilic rods spill from shelf or shelves inside the rotating cage and settle through feed inside the cage, collect . =
_ bitumen and oleophilic mineral particulates from the feed, and roll along cage bottom quadrant to transfer collected viscous oleophilic phase from oleophilic rods to oleophilic sieve.
The revolving sieve passes through a hot zone above the cage where collected viscous oleophilic phase on the oleophilic sieve becomes warm liquid product of separation due to viscosity reduction by heat. Hydrophilic mineral particulates and water flow as effluent from the cage through sieve apertures from the cage into the effluent tank.
Removal of effluent from the tank is controlled to keep the rotating cage and its contents mostly immersed in effluent in the tank with a level difference between cage and effluent tank to cause flow of processed feed into the tank.
COMPARISON WITH THE PRIOIR ART
Bitumen froth flotation, currently in commercial use for processing oil sand, heats up all water based oil sand slurry feed to 50 degrees C. for processing in flotation vessels, and then requires 360 minutes of process residence time inside these vessels to collect up to 95% of the contained bitumen as aerated froth product to be skimmed off the top. The process needs caustic to control pH of the flotation process for optimum bitumen froth production and deposits the high pH effluent water with suspended solids of separation into tailings pond for many decades of containment. The present patent application allows but does not require caustic in the separation process.
Unlike bitumen froth flotation which requires 360 minutes of process residence time at 50 degrees C., oleophilic sieve separation requires 15 minutes of process residence time at 35 degrees C. to achieve better bitumen product recovery and quality from oil sand slurry. It does not need caustic but it is tolerant of caustic. Both short processing time and absence of caustic makes oleophilic sieve separation an ideal candidate for mine face oil sand extraction. It will eliminate large pipe diameter abrasive transport of oil sand slurry to central processing, needing only a small diameter warm bitumen liquid pipeline to central upgrading. Not using caustic for commercial oil sand separation will allow reuse of process effluent water to process new oil sand after settling out mineral solids of prior oleophilic sieve separation for a few months, reducing or eliminating long duration tailings ponds.
BACKGROUND
Including prior granted Canadian patents of the instant inventor, the present invention differs from the prior art. It uses a not-previously patented separation concept of oleophilic rods spilling from bench or benches, inside a rotating cage. These rods settling through relatively cold feed inside the cage collect, on oleophilic rod surfaces, oleophilic phase from the feed, for subsequent transfer in cage bottom quadrant to oleophilic sieve or

2 sieves that cover exterior of the cage and project into cage interior. The oleophilic phase covered sieve surfaces then revolve through a hot zone for subsequent removal of oleophilic phase by heat from sieve surfaces as warm liquid product of separation. Unlike in prior patents of the present inventor, in the present patent application, hydrophilic phase of feed separation passes through sieve apertures of the relatively cold cage into an effluent tank in which the cage is immersed. Effluent, while passing from the cage through oleophilic sieve into the effluent tank also transfers residual bitumen to sieve surfaces upon contact, further improving oleophilic phase recovery.
OTHER PRIOR ART
Following are well-known examples of oleophilic phase adhesion, not to oleophilic sieves but to air bubbles or printing surfaces.
In 1860, William Hanes invented the separation of oleophilic sulfide from hydrophilic gangue material by rising air bubbles for froth flotation of oil wetted sulfide.
Many years later, in 1920, Dr. Karl Clark began his pilot plant study of separating Alberta oil sand at the Alberta Research Council in Edmonton, Canada, and subsequently invented and patented bitumen adhesion to air bubbles to separate a slurry of bitumen, water and sand into a bitumen froth product and a water and sand effluent.
Graphic artists and offset printing press developers, observing that oil based ink adheres to oil wet text and graphics but does not adhere to water wet surfaces, learning to repeatedly transfer ink wet images of a predominantly water wet master plate or marble tablet to many paper sheets in sequence.
None of the above methods used settling oleophilic rods to collect relatively cold oleophilic phase from feed inside a cage for transfer to an oleophilic sieve on cage circumference for subsequent removal from the sieve by heat as product, whilst hydrophilic effluent of separation and water flow through sieve apertures into an effluent tank surrounding most of the cage for controlled effluent removal.
OLEOPHILIC SIEVE SEPARATION
The concept of oleophilic sieve separation originated with the present inventor, who had operated an offset press, and therefore realized that oleophilic phase adhesion to oleophilic surfaces might be adapted to separate mined oil sand. He knew Dr.
Karl Clark, was familiar with bitumen froth flotation and had access to all the published and unpublished reports of Dr. Clark. About 10 years after Dr. Clark had retired and Suncor had built the first major commercial oil sands plant in Alberta, using bitumen froth flotation, the present inventor conceived and tested his oleophilic sieve separation concept for a year at the Alberta Research Council (ARC) while funding was made available. It resulted in his first Canadian oil sand separation patent application. When funding

3 terminated after a year of oleophilic sieve separation research, he entered into an agreement with ARC management to continue his research elsewhere. He assigned his pending first Canadian oil sand patent to the ARC and formed his own research establishment, employing engineers, chemists and technicians. Subsequent oleophilic sieve research lasting for decades resulted in many patent applications in progression filed by him and granted both in Canada, in the USA. The present Canadian patent application is his latest.
MODERN OLEOPHILIC SIEVE SEPARATION TECHNOLOGY
The present application for patent claims the unique use of a large number of long oleophilic rods inside a relatively cold rotating cage filled with feed for separation, which cage is covered with oleophilic sieve(s) that project into cage interior and with cage provided with ,one or more shelves inside the cage. During cage rotation, these shelf or shelves inside the cage assemble the oleophilic rods inside the cage, and subsequently spill from shelf or shelves the rods to settle through feed inside the cage during each cage complete revolution. During settling through feed, the rods collect from feed inside the age -- relatively cold viscous oleophilic phase on surface of the settling rods.
After settling through feed, the oleophilic phase coated rods roll along cage bottom quadrant and transfer, upon contact, viscous oleophilic phase from oleophilic rod surfaces to relatively cold oleophilic sieve, also transferring oleophilic phase between oleophilic rods for transfer to oleophilic sieve surfaces. After that, during each cage rotation, shelf or shelves again -- assemble oleophilic rods from along the cage bottom for subsequent spillage through feed as the cage continues to rotate.
More than one oleophilic sieve may cover side by side the cage exterior. Each oleophilic sieve contacting the cage has the shape of an incomplete polygon in which corners of each polygon are located at the longitudinal structural members of the cage and sides of each polygon project into the cage interior between adjacent longitudinal structural members to allow contact between oleophilic rods and oleophilic sieve. The polygon shape of each oleophilic sieve is incomplete since the oleophilic sieve leaves the cage near the top of the cage to pass through a hot zone above and/or beside the cage. In the hot zone, heat causes oleophilic phase to flow from the oleophilic sieve(s) as liquid product of separation.
Tension is provided in oleophilic sieve(s) to cause sieve movement as a result of cage rotation. After passing through the hot zone the oleophilic sieve, continue to revolve and return to the rotating cage.
The cage is immersed in effluent of oleophilic sieve separation in an effluent tank that surrounds bottom and sides of the cage. This immersion slows down liquid flow -- through oleophilic sieve from the cage into the tank by controlling level difference of feed inside the cage and of effluent in the effluent tank. Hydrophilic effluent of separation passes through apertures in oleophilic sieve and flows into the effluent tank, surrounding

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most of the cage, whilst uncollected residual oleophilic phase of the feed leaving the cage for the effluent tank is largely collected by oleophilic sieve surfaces.
Oleophilic phase sieving is a single stage continuous two temperature process which achieves very fast phase separations and is now ready for commercial development to reduce the cost of separating oil sands, tar sands, tailings pond fluid fine tailings, weathered oil spills, mine minerals and wet marine minerals. For processing mine, or sediment minerals, containing both hydrophilic and oleophilic mineral particulates, a viscous hydrocarbon such as petroleum jelly or bitumen, is added to the feed for collecting on oleophilic mineral particles for subsequent adhesion to oleophilic sieve surfaces as hydrophilic mineral particulates and water flow into the effluent tnak.
If needed, two oleophilic sieve separators may be used in series but normally this is not required to improve recovery of oleophilic phase. Fifteen minutes of residence time inside the rotating cage using a large number of settling oleophilic rods from shelf or shelves will recover most of the oleophilic phase present in a feed on oleophilic sieve.
Since feed for oleophilic sieve separation can be pH neutral (pH close to 7.0) the hydrophilic minerals in water effluent of oleophilic sieve separation, removed from the process, can settle relatively fast to the bottom of a tailings pond. This will allow, within a few weeks or a few months, recycle of a very high percentage of tailings pond water for reuse, in oleophilic sieve separation, to reduce demand for fresh water for oil sand or minerals separation. This serves to reduce the current negative environmental impact of oil sand development and tailings ponds expansion.
In some cases, water from existing old oil sand tailings pond fluid fine tailings (FFT), in large quantity may be considered as an optional source of process water to use for mined oil sand extraction by oleophilic sieve. Oleophilic sieve separation is tolerant of mineral fines and is generally not impacted much by process water pH, at least between 6 and 8. This could lead to the simultaneous recovery of new bitumen from mined oil sand and old bitumen from pond FFT. It is an option that should be considered as a future means to empty existing tailings ponds, thereby producing bitumen from both new mined oil sand ore and from old pond FFT, while benefitting from reduced fresh separation water demand.
Oleophilic sieve slurry separation of oil sand slurry as disclosed in the present patent requires about 15 minutes of process residence time and does not need caustic. The hydrophilic minerals in the effluent of oleophilic sieve separation, using fresh water, settle relatively quickly and the resulting effluent water of separation can then be reused as process water for separating fresh oil sand after first settling the effluent water for a few months. Recycling process water in that manner will reduce in a major way the environmental impact of oil sand processing.

5 Unlike froth flotation, which requires all feed at 50 degrees C, oleophilic sieve separation temperature inside its cage normally is around 40 degrees C. or lower, depending on feed composition. Product leaving the hot zone of oleophilic sieve separation may be at a much higher temperature beneficial for further processing. Since the relatively cold cage handles the bulk of the feed for processing, and the hot zone only heats the product, commercial oleophilic sieve separation energy demand will be relatively low.
Because of caustic use, current effluent of commercial oil sand separation by froth flotation cannot be safely discarded but requires permanent impounding of its fluid fine tailings (FFT) in large tailings ponds to prevent toxic release to the environment. After years of minerals settling, only the upper layers of oil sand tailings pond are currently reused as part of water make up for froth flotation of oil sand slurry. The oil sand tailings ponds are very large and are considered an environmental problem. When oleophilic sieve separation of mined oil sand is implemented commercially, the negative environmental impact of oil sand tailings will be reduced.
The oleophilic sieve was very effective for processing existing tailings ponds fluid fine tailings (FFT) to recover discarded bitumen in a two year field pilot project costing well over $1 million. Removing bitumen from tailings pond effluent (FFT) is expected to result in cleaner tailings ponds that represent less of an environmental hazard, and recovering in the process a substantial amount of valuable bitumen. An episode of a large number of migrating ducks landing on and dying in an oil sand tailings pond is still remembered by many.
TYPES OF OLEOPHILIC SIEVES
There are at least three types of conveyor belts suitable for use as oleophilic sieves.
These include conventional metal belts formed from strips of metal shaped in the form of an almost square square wave with holes punched in the metal strips to accept rods to pass through the holes to join the metal strips and form a flexible endless belt.
The square wave shape is lightly tapered to allow the formed strips to mesh into adjacent formed strips and thus form a long belt of hinges that can be made endless by joining belt end to belt beginning. Another type of belt is formed from flattened metal coils that are joined by rods passing through adjacent flat coils to form a multitude of interconnected flat coils with the starting coil connected to the last coil by rod.
A more preferred belt for use as an oleophilic sieve comprises multiple wraps of a rope made endless by joining the end of the rope to the beginning of the same rope. This type of oleophilic sieve is shown in the drawing of Figure 1 and especially in Figure 11 and may be made from plastic rope, from metal rope or from carbon fiber rope.
Figure 11

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shows two such sieves made endless by joining the start of each rope to the end of the same rope. As shown in Figure 11 two rope wrap redirecting guide rollers are needed to keep each sieve of equally spaced sieve wraps on cage from rolling off a drum or cage.
A nice feature of an endless oleophilic sieve of parallel rope wraps is that, at the rakes the space between adjacent wraps is fixed by rake tine and valley spacing but, between rakes on a cage, two adjacent wraps can spread to allow passage of hydrophilic particles much larger in size than distance between adjacent rake valleys.
When this happens, space between the spread wraps is increased locally and space between each spread wrap and adjacent neighbor wraps is reduced. It allows oversize mineral particles much larger than distance between rake valleys to spread sieve wraps for such particles to leave the cage and enter the effluent tank. Rake valley spacing prevents wrap spacing at the rakes but allows, between rakes, local wrap spreading and corresponding adjacent local wrap crowding between rakes for oversize mineral particles to leave the cage.
As shown in Figure 11, two pulleys on each oleophilic sieve of rope wraps redirect sieve wraps so that those wraps never roll off the cage nor off the rollers that guide the sieve wraps between cage and hot zone. When conventional endless conveyor aperture metal belts are used for oleophilic sieves, such pulleys are not needed.
ROPE WRAP COMMERCIAL OLEOPHILIC SIEVE SEPARATORS
Three sizes of commercial oleophilic separators are detailed in Table Figure 8 with cages respectively 2, 4 and 8 meters in diameter each using endless oleophilic ropes for the sieve(s) similar to Figure 11 on cages detailed in Figures 1, 2, 3 and 12 instead of on aperture drums. The cages are immersed in an effluent tank as detailed in Figures 3 and 12.
All three cages feature a strong central shaft for cage construction, two strong end walls and a number of longitudinal structural members equally spaced along the periphery of the cage end walls provided with rakes to space the rope wraps. The diameter of the longitudinal structural members of the cage should be small enough to allow oleophilic rods to roll and tumble in cage bottom quadrant for directly or indirectly transferring oleophilic phase to the oleophilic sieve(s); but are sufficiently strong to support without observable bending oleophilic sieve wraps in tension that take the form of incomplete polygons supported on the structural longitudinal members. The central shaft prevents bending of the cage. The weight of settled oleophilic rods inside the cage is mainly carried by the central shaft of the cage in bearings, since hoops or flat bar welded to the cage end walls transfer weight of settled oleophilic rods inside the cage to the central shaft via the end walls.
When more than one oleophilic sieves is used on a cage, a hoop or an assembly of flat bars also is located between adjacent sieves to space the sieves, to give room for

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bearings and bearing mounts of sieves and to prevent spillage of feed into the effluent tank between adjacent sieves. Hence, when two oleophilic sieves are used on a cage, three sets of hoops or three assemblies of flat bars are needed. When three oleophilic sieves are used on a cage, four sets of hoops or four assemblies of flat bars are needed, etc.
MINE FACE OLEOPHILIC SIEVE SEPARATION
Oleophilic sieve separation appears thus far to be the only hot water process replacement technology suitable for mine face oil sand extraction because of its simplicity and its very short processing residence time. As detailed in Table Figure 8, each commercial 8 meter diameter, 24 meter long oleophilic sieve separator is designed to process 83,000 cubic meters of oil sand slurry per day. When three such separators are used, one at each mine face, total oil sand slurry for mine site extraction will amount to about 250,000 cubic meters of slurry per day, each separator producing good quality bitumen product for shipment by liquid pipeline to central upgrading. Using skid mounted units at the mine face, and enclosing each unit as needed, will allow oleophilic sieve separation equipment to move with an advancing mine face. An important feature of oleophilic sieve separation is that slurry production for oleophilic sieve separation is simpler and faster than slurry production for bitumen froth flotation.
In pilot plant studies of the present inventor, separating mined oil sand slurries by oleophilic sieve, the presence or absence of caustic in the feed made little difference. It indicated that for commercial oleophilic sieve separation of mined oil sand slurry, caustic will not be needed either. When caustic is not needed for commercial oleophilic sieve separation of mined oil sand, mineral particulates in the water effluent of oleophilic separation at neutral pH will settle rapidly and will allow tailings pond water to be reused in commercial oil sand extraction after settling for a few months. This reduces in a major way the need for fresh water in commercial mined oil sand separation by oleophilic sieve.
In pilot plant studies, not 360 minutes, but less than 15 minutes of oleophilic sieve separation of oil sand slurry yielded a very acceptable bitumen product and clean tailings.
Field piloting by oleophilic sieve separation of tailings pond FFT also retrieved in a few minutes a high percentage of prior discarded bitumen from froth flotation extraction. All this indicates that existing tailings pond fluid fine tailings (FFT) may be considered a potential source of useful water to process mined oil sand to recover new bitumen from mined oil sand and old bitumen from FFT at the same time.
Water washing the bitumen product with clean water, optionally including a chemical reagent, may thereafter remove hydrophilic mineral from the resulting bitumen product, as was achieved in our pilot plant when cleaning up bitumen produced from pond FFT.

8 OTHER USES
The cages described above may also, instead of sieves of endless rope, use endless conventional open area (i.e. aperture) metal conveyor belts, of the type described in this patent, on cage longitudinal structural members and projecting into cage interior similar to sieves of endless rope. In that case rope guide pulleys, (73a and 73b) shown in Fig. 11, are not needed. These conveyor belts have a selected constant opening size which prevents hydrophilic particulates beyond a given particle size age. In some cases a punched metal sheet conveyor may be used or an open area woven plastic belt. However, an oleophilic sieve of multiple wraps of oleophilic rope is more versatile and long lasting, especially when the oleophilic rope comprises twisted metal wire to which bitumen will adhere.
An oleophilic sieve separator designed for processing oil sand slurry may be used to recover bitumen from tailings pond FFT without the need for a slurry tumbler.
In side by side field testing to separate 120 metric tons of tailings pond FFT, the bitumen froth flotation pilot plant had a process residence time of 26 minutes and the oleophilic sieve pilot plant had a process residence time of 2 minutes. The product of froth flotation contained 25% bitumen and the product of oleophilic sieving contained 58%
bitumen. In other words, oleophilic sieve separation was 13 times as fast, irrespective of equipment size and the bitumen product was twice as pure. Process residence time is a process parameter independent of equipment size and is used for evaluating process performance.
Oleophilic sieve separation may also be used to clean up oil spills but that is not its current development objective. For separating mine minerals, bitumen or viscous other hydrocarbon is added to a water wet slurry of mine minerals for oleophilic sieve separation.
Such oleophilic phase addition will coat the oleophilic mine minerals in the slurry for subsequence adherence to oleophilic rods and to oleophilic sieve surfaces whilst hydrophilic minerals remain water wetted and flow with water as effluent of separation through apertures of the oleophilic sieve into the effluent tank.
THE PRESENT PATENT APPLICATION
The present patent application describes the construction and operation of oleophilic sieve(s) wrapped around part of a rotating cage, and passing through a hot zone; including an effluent tank in which the cage is immersed. The present claims are specific to a rotating cage in part filled with feed and in part filled with oleophilic rods. Shelf or shelves supported inside the cage collect the oleophilic rods on shelf for subsequent spillage from bench into cage interior due to cage rotation. The spilled oleophilic rods settle through feed inside the cage and collect oleophilic phase on rod surfaces from the feed. At least half of

9 the cage circumference is void of shelf or shelves, which allows the rods to roll and tumble along bottom quadrant of the cage for transfer of oleophilic phase between oleophilic rods and from oleophilic rods to oleophilic sieves, for conveyance of the sieve and contents through a hot zone to yield warm good quality oleophilic product flowing from the sieve.
This further results in a relatively clean hydrophilic effluent of water and hydrophilic minerals, which after the minerals have settled may be used to process more feed since caustic is not needed for oleophilic sieve separation. Minerals settle reasonably fast in aqueous effluent of separation when its pH is close to 7Ø
In the hot zone, heat removes the oleophilic phase as product of separation from the sieve. The cage is immersed well over half in a tank containing the hydrophilic effluent of oleophilic sieve separation.
Immersion of a rotating cage in effluent, combined with oleophilic sieve(s) on an immersed cage exterior and with sieve projecting into cage interior to improve bitumen collection, and combined with collection of bitumen from processed feed entering the effluent tank, while passing through oleophilic sieve, was not disclosed in any other currently pending or granted patents of the present inventor.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a drawing of an oleophilic sieve cage. It consists of two circular disc types end walls with eight longitudinal structural members equally spaced along cage circumference and attached to each end wall inside face. Five of the eight structural members are shown. The other three are hidden by the shown structural members.
The cage has a central shaft, to mount the cage in secured bearings and to drive slow cage rotation, using a gear box and motor (not shown). A manhole with cover is provided in at least one of the end walls for inserting and removing long oleophilic rods to and from the cage. One and preferably two or more oleophilic sieves surround most of the cage in the form of either multiple wraps of endless oleophilic rope that are supported by longitudinal structural members and are equally spaced by rakes on the longitudinal structural members, or in the form of aperture metal conveyor belts. The oleophilic rope may be made from plastic or from metal. Two oleophilic sieves of equal length on a separator simplify construction and keep the hot zone parallel with the cage in this Figure.
Figure 2A is a drawing of the cage viewed from inside the cage with oleophilic sieve wraps at least covering the cage bottom and sides, showing a metal hoop surrounding the longitudinal structural members. This metal hoop is shown as a thin line to allow showing the thick dashed line sieve. The cage contains some oleophilic rods in the cage to show curvature of sieve due to oleophilic rod weight but constrained by the hoop.

Figure 2B is the same drawing as Figure 2 except that the metal hoop is replaced by eight straight flat bars mounted between longitudinal structural members and projecting for a short distance beyond the inside face of each end wall to support the weight of oleophilic rods on the flat bars between longitudinal structural members due to contact between oleophilic rod ends with the straight flat bars. It shows a single oleophilic sieve which hides the straight metal bars except near the top of the cage. The circles with a cross in each represent oleophilic rods inside the cage.
Figure 3 shows the cage immersed in an effluent tank and shows a hot zone above and beside the cage. The cage also shows a single shelf that, due to cage rotation, has collected all the oleophilic rods in the cage ahead of shelf inside the cage.
As the cage rotates slowly, all the oleophilic rods will gradually spill from the shelf to collect relatively cold oleophilic phase from the feed. After each spill, settled oleophilic rods directly or indirectly transfer collected oleophilic phase to the sieve as a result of transfer of oleophilic phase between rolling oleophilic rods in cage bottom quadrant. This sequence is repeated with every cage rotation. Oleophilic sieve(s) convey viscous oleophilic phase into a hot zone where heat converts the viscous oleophilic phase into warm liquid product of separation.
Figure 4A illustrates a cage with a curved single bench connected between the cage central shaft and one of the longitudinal structural members. This bench, in its simplest form consists of two or three curved bars attached to the central shaft and to one of the longitudinal structural members. The bench has collected all oleophilic rods due to cage rotation.
Figure 4B illustrates gradual spilling of the oleophilic rods from the curved bench inside the cage due to cage rotation. The use of a curved shelf allows for longer duration of spillage of rods from the shelf during each rotation of the cage.
Figure 5 illustrates the use of four curved benches inside the cage. Enough rods are provided in the cage to fill almost all four benches with rods. During about half of each cage rotation, each bench in sequence spills rods inside the cage interior to settle through feed and collect oleophilic phase from the feed, and then allows, during the other half of each cage rotation, transfer of collected viscous oleophilic phase between oleophilic rods rolling along cage bottom quadrant and from rods to oleophilic polygon shaped sieve projecting into cage interior.
Figure 6 illustrates a typical rake to space the rope wraps of an oleophilic sieve.
Such a rake is normally inserted and fastened in a groove of every, or alternate longitudinal structural member of a cage, with depth of insertion into the longitudinal structural member, indicated by the dashed line. A rake with tines of sloping sides tends to provide extra friction between tines and rope wraps. When a conveyor is used for the oleophilic sieve, the rake is adapted to accept surfaces of such a conveyor.
Figure 7 illustrates a longitudinal structural member of the cage in the form of a round bar or half round bar (above dashed line at bar center). A rake is shown inserted in the longitudinal structural member and the heavier dashed line shows a sieve wrap in the rake.
Figure 8 is a table of recommended commercial separator sizes with details and estimated separation capacities.
Figure 9 provides details of a typical oleophilic sieve separator effluent tank end wall to allow immersion of the cage into effluent of separation.
Figure 10 provides details of mounting a rotary seal and a shaft bearing in the end wall of the effluent tank.
Figure 11 provides details of prior patented art of the inventor to prevent oleophilic sieve from rolling off an aperture drum. Only two pulleys in total keep the wraps of a sieve from rolling off rotating drum and associate rollers. This concept of using only two wrap directing pulleys or sheaves is also used in the present patent by the inventor to prevent oleophilic sieve wraps from rolling off an immersed cage.
Figure 12 is similar to Figure 3 except that in Figure 12 the cage rotates in opposite direction (counter clockwise), resulting in bitumen loaded sieve entering the hot zone as the top flight for product removal, whereas in Figure 3 the cage rotates clockwise, resulting in the bitumen loaded sieve entering the hot zone as the bottom flight for product removal. In most cases the more effective method is illustrated in Figure 12, since it reduces heating of the empty sieve prior to returning from the hot zone to the cold cage.
DETAILED DESCRIPTION OF THE FIGURES
Figure 1 is a drawing of one of the smallest of the three oleophilic sieve cages detailed in Table Figure 8. It consists of two circular disc type end walls (10,11), two meters in diameter and six meters long with eight longitudinal structural members (1,2,3,4,5,6,7.8) equally spaced along cage circumference and attached to each end wall (10,11) inside faces (10a, 11a). Five of the eight structural members (1,2,3,4,5) are shown.
The other three (6,7,8 ) are hidden by the five shown structural members, The cage has a central shaft (9). The central shaft (9) is securely mounted in bearings and bearing mounts (not shown) to be slowly driven to rotate, using a gear box and a motor (not shown). A
manhole with cover (12) is provided in at least one of the end walls (10, 11) for inserting and removing long oleophilic rods to and from the cage. One such rod (15) is shown inside the cage. It is long enough to be prevented by hoop (13) or eight flat bars (See Fig 2) from leaving the cage. A hoop (14) or eight flat bars at cage mid length provides for spacing the two sieves (18, 19) for mounting of components to position two sieves. The two oleophilic sieves (18, 19) surround most of the cage circumference. The sieves (18,19) are illustrated in the form of dashed lines that are supported by the longitudinal structural members (1 to 8) and, when in the form of endless rope are equally spaced by rakes (not shown) on the longitudinal structural members. Hoop or eight straight bars (13) of limited width are used between the longitudinal structural members (1,2,3,4,5,6,7,8) as detailed in Figures 2A and 2B, These flat bars are welded to the inside face (10a, 1 1 a) of each end wall (10,11), and/or are welded to the longitudinal structural members (1,2,3,4,5,6,7,8) for a short distance on each of those members near cage end walls inside surfaces (10a, 11 a) to prevent oleophilic rods from putting excess stress on the oleophilic sieve and to prevent rods from getting caught between sieve(s) and cage end wall circumference. Similar hoop or eight straight bars (14) indicated in black on Figure 1 are shown at cage mid length to separate the two sieves (18,19). The hoops or bars (13) at cage end walls prevent weight of oleophilic rods from putting excess stress on sieve(s) (18, 19) when the cage rotates. The single hoop or eight straight flat bars (14) at cage midpoint allow for mounting roller supports at sieve edges and to prevent spillage of unprocessed feed into the effluent tank. The hoops or flat bars at midpoint also provide rigidity to the cage by connecting to all longitudinal structural members at cage midpoint. More detail is provided with Figures 2A and 2B. The longitudinal structural members (1,2,3,4,5,6,7,8,) normally are of small diameter, using high tensile steel, and provide support for the oleophilic sieves (18,19) on the cage to encourage contact between settled oleophilic rods and oleophilic sieve wraps mainly in the bottom quadrant of the cage, while minimizing obstruction to oleophilic rods rolling along cage bottom quadrant. The central shaft and the two end walls provide most of the structural integrity of the cage. For large diameter cages the number of longitudinal structural members may be increased, still allowing oleophilic sieve to project into cage interior. For example, a four meter diameter cage could have 12 longitudinal structural members, still allowing the oleophilic sieve(s) (18, 19) to suitably project into cage interior.
Each sieve thereby takes on the form of an incomplete polygon with straight polygon sides between the longitudinal structural members, with the structural members (1 to 8) forming the corners of each incomplete polygon, as illustrated in the next Figures.
The polygon of each sieve wrap is incomplete since each sieve wrap leaves the cage to pass through a hot zone and back to the cage.
Figure 2A is a drawing of the cage viewed from inside the cage showing one oleophilic sieve (18). It shows a central shaft (9) and circumference of end wall (10). It shows eight longitudinal structural members (1,2,3,4,5,6,7,8) and shows a hoop (61) of metal, which is attached to each end wall (10) and attached over a short distance from cage end wall along each longitudinal structural member (1 to 8) to said members.
These hoops (61) support the oleophilic rods (15) near oleophilic rod ends and prevent rods from misaligning and attempting to leave the cage. Oleophilic rods (15) are illustrated in Figure 2A by circles, each with a cross inside. Noteworthy is that along cage bottom the sieve(s) (18) deflects and conforms to the hoop (61) along cage bottom due to weight of oleophilic rods (15).
Figure 2B is similar to Figure 2A except that the hoop of Figure 2A is replaced by eight straight flat bars (13) of limited width, welded to the end wall and welded for a short distance to the longitudinal structural members (1,2,3,4,5,6,7,8) of the cage.
A single oleophilic sieve (18) is added to the Figure to show the location and shape of each incomplete polygon of sieve along the cage. Figure 2B uses eight flat bars instead of a hoop. Each sieve (18) in the Figure hides the metal flat bars (13), except along the top of the cage where the wraps leave the cage to move to and from the hot zone above the cage.
As in Fig. 2A, in Fig. 2B, each sieve (18) forms a polygon with straight sides between longitudinal structural members (1 to 8) but aligns with the metal flat bars (13) in Fig. 2B
which are welded to the end wall inside faces (10a, 11 a) and for a short distance to the longitudinal structural members. Noteworthy in Figure 2B is that the oleophilic rods do not put pressure on the sieve since the oleophilic rods are supported by the flat bars (13). Only near the top of the cage are two flat bars (13) clearly visible, not hidden behind the sieve (18). In both Figures, the oleophilic rods can roll along the cage bottom quadrant of the rotating cage. Less stress is imposed on the oleophilic in Figure 2B but more contact is achieved between oleophilic rods and oleophilic sieve in Figure 2A. Both methods (Figure 2A and Figure 2B) may be used in the cages of the present invention to keep oleophilic rods inside the cage and provide contact between rods and sieve for oleophilic phase transfer.
Figure 3 shows the cage immersed in an effluent tank (30) and a hot zone (37) above and beside the cage (68). The cage also shows a single bench (20) that, due to clockwise cage rotation, has collected together all the oleophilic rods (23) in the cage. As the cage (68) rotates further and the bench (20) approaches a horizontal position and beyond, all the oleophilic rods (23) will in sequence spill from the bench (20) to settle through feed inside the cage (68) to collect oleophilic phase from the feed inside the cage on the rod (23) surfaces. A typical bench (20) comprises two or three widely spaced straight parallel bars between the cage central shaft (9) and one of the longitudinal structural members, member (1) in this case. The hot zone (37) in this figure uses heat radiators (38) above the sieve (18) entering the hot zone (37) as the bottom flight, after passing over a guide roller (33). A heat reflecting surface (39) covered by insulation (40) above the heat radiators (38) in the hot zone limits further heating in the hot zone of oleophilic sieve surface returning to the cage before passing over guide roller (34). The oleophilic phase depleted sieve passing over guide roller (34) may next be pre-coated with oleophilic phase supplied by a slip stream (21) of feed controlled by a valve (22). The long distance between roller (34) and cage (68) provides time for pre-coating of the warm, oleophilic phase depleted, oleophilic sieve with cold fresh oleophilic phase from a slip stream of feed. Pre-coating the sieve surfaces with bitumen reduces the flow of oleophilic phase through sieve apertures after these return to the cage along the right quadrant of the cage, especially when a curved optional containment baffle (17) along cage exterior restricts the flow of feed through the sieve returning to the cage along the cage right cage quadrant.
All the feed (24) for separation, except for the slip stream (21), enters through a control valve (25) and a feed distributor (26) to fill the cage to a desired level (27) and initially also fills the effluent tank to that level, depositing some oleophilic phase (bitumen and bitumen coated particulates) to the sieve (18) as it enters the effluent tank (29). A
tension roller (35) provides tension (45) to the sieve, which enters the hot zone by passing over guide roller (33) and returns to the cold cage by passing over guide roller (34). Warm oleophilic product (43) leaves the hot zone for collecting through a chute (44) for further processing or upgrading. When the hot zone contains flammable gasses, an inert gas (41) is introduced into the hot zone to remove flammable gasses from the hot zone through a stack (42) Once the separator is operating, the contents of the effluent in the tank (29 is dropped to a desired level (28) that is lower than the level (27) of feed being processed inside the cage, so as to encourage outflow of effluent from the cage into the effluent tank.
Thereafter, most of residual oleophilic phase that leaves the cage with effluent is captured by the oleophilic sieve before it enters the tank. A control valve (32) controls the outflow of effluent (31) from the tank. Normally a computer is used to control the flow of feed into the cage by valve (25) and the flow of effluent (30) out of the tank controlled by a valve (32) to become the effluent (31) of oleophilic sieve separation. These flow monitors control the difference in level (27) inside the cage and level (28) in the tank. When large hydrophilic mineral particles are present in the effluent, a conveyor may be used to remove these from the tank (29). Alternately, the effluent exit valve may be controlled to cycle from fully open to fully closed, under computer control to allow mineral particles with effluent to pass through the effluent exit valve (32). Similarly the feed distributor (26) may be adapted to accommodate entry of hydrophilic particulates into the cage by cycling the feed entry valve (25) from the fully open to the fully closed position, using suitable valves for that purpose. Alternately the feed (24) is pre-screened to remove particle of a given size before feed enters the cage.
During operation the rotating cage spills all the contained oleophilic rods from bench during each cage rotation to collect oleophilic phase from feed inside the cage as the rods settle though feed inside the cage. The rods (23), after reaching the bottom of the cage roll along the bottom quadrant of the cage to transfer oleophilic phase collected from the feed to the sieve upon contact, including the transfer of oleophilic phase between oleophilic rods for transfer to the sieve. As shown in the Table Fig. 8, it is estimated that during every 15 minutes of operation the 2 meter diameter, 6 meter long cage, rotating at

10 RPM, spills 460 cubic meters of oleophilic rods inside the cage (during 150 cage rotations) and, as a result, captures nearly all the bitumen or oleophilic phase from the feed for transfer to the sieve which conveys it into the hot zone (37) to produce warm oleophilic phase product.
The effluent of separation, when it still contains oleophilic phase transfers oleophilic phase to the sieve upon contact whilst the effluent flows into the effluent tank.
Large cages of Table Figure 8 rotate at a slower rate than small cages since the oleophilic rods need to settle for a longer distance in the large cages but spill more oleophilic rods every 15 minutes because of the larger cage volume.
Circumference surface speed of all cages is initially set at 1 meter per second to minimize effluent turbulence in the tank. This speed may be increased if shorter residence of feed in the cage is desired, or may be decreased if longer residence of feed in the cage is desired. During some pilot plant tests, only a few minutes of residence time was needed in small diameter cages to achieve good product recovery and effluent that contained very little product.
Figure 4A illustrates the cage provided with a curved single shelf (58) connected between the cage central shaft (9) and one of the longitudinal structural members (2). This shelf (58), in its simplest form consists of two or three spaced bars, each in the form of a half circle attached to the central shaft (9) and to the same longitudinal structural member (2) which may be increased in diameter as needed for strength. In the Figure the shelf (58) has collected all the oleophilic rods in the cage due to cage rotation. Again, the dashed line, representing a sieve, hides the bars (13) between the longitudinal structural members, which bars support the oleophilic rods (23). Near the top of the cage, where the sieve (18) leaves for or returns from the hot zone, are the flat bars (13) clearly visible Figure 4B illustrates gradual spilling of oleophilic rods (65) from the curved bench.
The curved bench (58), instead of being a straight shelf allows for more gradual rod spillage inside the cage during cage rotation. A dashed line (64) illustrates how large a percentage of the rods (23) on shelf (58) have spilled from the shelf and settle as settling rods (65) through feed to collect oleophilic phase from feed inside the rotating cage after the cage has rotated one eight of a turn to transfer collected oleophilic phase from settled rods to sieve (18).
Figure 5 illustrates the use of four curved short shelves (58) inside the cage to allow during each cage rotation gradual spillage of rods inside the cage interior that contains feed for separation to collect on their surfaces oleophilic phase from feed inside the cage. In this case, the number of oleophilic rods inserted in the cage does not exceed a volume of rods that can be contained on the four shelves in total. Each of the four benches in sequence then collect its allotted number of oleophilic rods during each single cage rotation and spill these in sequence into the feed contained in the rotating cage. As with other types of shelf or shelves in the cages of the present invention, the spilled oleophilic rods, after collecting oleophilic phase from the feed inside the cage roll along the cage bottom quadrant to transfer oleophilic phase between the rods and from the rods to a metal oleophilic sieve or to oleophilic sieve rope wraps. Oleophilic phase not captured by the oleophilic rods is collected by oleophilic sieve as effluent of processed feed flows into the effluent tank.
Multiple shelves in a cage tend to extend the time of total rod spillage inside a cage during each 360 degrees of revolution of the cage.
Figure 6 illustrates a typical rake with tines (49) and valleys (50) to space wraps (51) of oleophilic sieve when wraps instead of aperture conveyor belts are used. Such a rake is normally inserted in the groove of every, or alternate longitudinal structural members of a cage, with depth of insertion indicated by the dashed line (59).
Valleys between rake tines may taper to put pressure on sieve wraps for friction between rakes and wraps for sustained movement of wraps with cage circumference.
Figure 7 illustrates a longitudinal structural member of the cage in the form of a round bar (52) or a half round bar (53 above the dashed line). A rake (48) for a sieve of rope wraps, shown inserted in the longitudinal structural member is normally contained therein by friction, by an adhesive bond, by silver or brass solder or by spot welding.
Figure 8 is a table of proposed commercial oleophilic sieve separation cages.
The table provides structural dimensions, cage sizes and capacities, predictions of cage performance and number of rod spills from shelf during 15 minutes of oleophilic sieve separation residence time in each cage. The larger the cage, for a given cage surface speed, the slower the rotation RPM, and the longer the settling time of rods in a cage and the larger the volume of rods spilled from each shelf. The foot note in the table identifies yellow jacket pipe as the preferred source for producing oleophilic rods.
Yellow jacket pipe has a very strong bond between the parent steel pipe and its yellow plastic cover for long lasting use as oleophilic rods and is readily available. Threading each steel pipe end and putting a threaded pipe cap or threaded or inserting a pipe plug at each end closes each yellow jacket pipe to form an oleophilic rod for the present invention.
Oleophilic rod density is then controlled by the selection of yellow jacket pipe diameter for Schedule 40 pipe, which is the common type of yellow jacket pipe. Normally the yellow jacket pipe is dense enough not to require added weight inside the pipe, but filling each pipe with some weight is an option. For Schedule 40 empty yellow jacket pipe the capped pipe density will tend to be determined by the pipe outside diameter. As the need arises, yellow jacket pipe or tube may yet be produced in schedules 5, 10 and 20 grades to allow the use of smaller diameter pipes for a desired empty pipe density at a given pipe diameter, Fiber glass pipe, sandblasted on the outside to increase adhesion of oleophilic phase to its outside surface, is another source for fabricating oleophilic rods. In that case, the fiber glass pipe normally needs inside loading to achieve a desired oleophilic rod density for settling through feed inside a rotating cage at a desired rate.
Alternately oleophilic rods that may be used in cages of the present invention are capped steel tubes or steel pipes covered with a plastic (PVC, urethane, polypropylene or other plastic) pipe slid over the steel pipe or tube OD. Painting an oleophilic coating on a steel pipe or tube tends to wear too fast for use in commercial oleophilic sieve cages unless applied in a thick abrasion resistant layer.
Figures 9 and 10 provide details that may be used for mounting the cage in an effluent tank. Figure 9A shows one of the two end walls (66) cut with cut-out to accept a bearing and rotary seal plate (Fig. 9B). "Figure 9B enlarged" shows the same seal plate and Figure 10 shows side view of the seal plate provided with a rotary seal (71) at one face and a flange mount bearing on the other face. During construction a seal plate, complete with rotary seal and flange mount bearing is inserted over each projecting central shaft end, such that the seal faces inward into the tank near the cage end wall. Then, the separator cage, with hot zone and oleophilic sieves attached, is lowered into the tank and seal plates are bolted to both tank end walls. Then, motor and gear box(es) are attached to drive rotation of the cage. If desired, a heavy shaft mount gear box may be mounted on the shaft of the cage external to the tank, with additional gearing and/or belt or roller chain to drive slow rotation of the cage to achieve a desired cage surface speed without creating too much turbulence in the effluent tank. Other ways of mounting the rotatable cage inside a stationary effluent tank may be used without invalidating the present patent.
Figure 11 illustrates prior art of the present inventor for preventing oleophilic sieve wraps (18 or 19) from rolling off drum, cage or roller, using two pulleys or sheaves (73a and 73b) for each sieve (18 or 19) to redirect a wrap about to roll off the end of a cage.
Figure 12 is similar to Figure 3 except that the cage rotates counter clockwise, such that each oleophilic phase loaded sieve enters the hot zone as the top flight by passing over top guide roller (34) to travel under heat generators (38) covered with a heat reflector (39) mounted along the top of the hot zone enclosure (37). Warm product (46) leaving sieve top flight(s) flows over enclosed insulation (40) and thereafter sideways out of the hot zone ahead of the sieve tension roller (35) to be collected in the product exit (44) for leaving the hot zone as product (43) of separation. As a result, each bottom flight in the hot zone of Figure 12 is colder than each top flight in the hot zone of Figure 3, which enhances subsequent adhesion of oleophilic phase to sieve surfaces leaving the hot zone for the cold cage. An optional slip stream (21) of feed with control valve (22) impacts the sieve surfaces leaving the hot zone returning to the cage. Similar to Figure 3, an optional baffle (17) along sieve (18) returning to the cage prepares the returning sieve for optimum collection of oleophilic phase from effluent leaving the cage for the effluent tank, slowing by baffle (17) the flow between cage (68) and tank (29). Since the cage (68) of Figure 12 rotates counter-clockwise, the oleophilic rods collect to the right of the bench (20) during cage rotation. Noteworthy is that in Figure 3 the sieve hotter wraps returning from the hot zone to the cage have a longer distance of travel for cooling than the cooler wraps in Figure 12. Each of the two separators (Fig 3 and Fig 12) may be adapted for use with a specific feed.
THE HOT ZONE
Various types of hot zones were described in previous patents of the inventor, which used internally heated drums and guided oleophilic sieves differently than in the hot zones shown in Figures 3 and 12 of the present patent. Many such prior types of hot zones are suitable for use with the present invention. In Figures 3 and 12 the hot zones use non contacting heating elements to warm the oleophilic sieve and its adhering product by radiant heat. This new design allows for more effective release of oleophilic product from sieve surfaces, with less wear and tear on oleophilic sieve(s). Compared with previous patents, for example Canadian 2,999,466 or US 10,399,008, the present invention allows more sieve coverage of cage circumference, using a shorter distance of uncovered cage for feed to enter the cage. More sieve coverage on a cage allows for higher feed levels inside the cage for feed processing. Unlike the above quoted patents, having an effluent tank, with effluent of oleophilic separation surrounding most of the cage, improves efficiency of the separation process, as compared with a cage not surrounded by effluent and also allows for simpler cage construction. The cage of the present invention, being immersed in effluent of separation, provides buoyancy and slows the outflow of effluent from the cage for more efficient feed separation. Unlike the above quoted patents, the use of bench or benches in the present invention to elevate oleophilic rods for settling through feed, for subsequent rolling along cage bottom quadrant to transfer oleophilic phase between rods and from rods to sieve, also provides for major improvements in cage separation performance.
SHORT CAGES
Oleophilic rods in short cages do not work well when the inside cage length is shorter than the cage end wall diameter. Oleophilic rods may misalign in such short rotating cages. Only round balls or other types of short bitumen agglomerating instruments work successfully in short drums or cages. Weighted golf balls worked well in pilot plant studies using short drums. For feed separation tests in such drums, each golf ball was provided with a drilled central hole and tapped with a thread for inserting added weight to each ball and thereby achieve a desired ball density inside the cage or perforated drum to collect oleophilic phase for the oleophilic sieve. A short piece of threaded steel rod was screwed into each golf ball to increase its density to a desired amount. Each threaded rod was slightly shorter than the golf ball diameter. Steel threaded rods of various diameters were used to achieve a desired mix of modified golf ball densities. This worked well to collect oleophilic phase from feed to oleophilic sieve surfaces in initial pilot plant studies.
Similar ball densities may be achieved by casting balls from plastic, using hollow metal balls or metal particulates to add weight to balls in the casting process.
PASSAGE OF HYDROPHILIC PARTICULATES
When oleophilic sieves of adjacent wraps of endless rope are used to separate a feed that contains hydrophilic gravel, and all sieve wrap surfaces, are spaced by rake 0.5 centimeter apart, fine gravel not much larger than 1.0 centimeter in maximum dimension can pass out of the cage by locally spreading two adjacent sieve wraps to allow for such passage. As a result of locally spreading space between two adjacent wraps, the space between each spread wrap and its non-spread adjacent neighbour wrap is locally narrowed.
The same applies for sieve wraps that are spaced by rake 1.5 centimeters apart to allow fine gravel not exceeding 3 centimeters in maximum dimension to pass out of the cage by locally spreading adjacent wraps, etc. Consequently, oleophilic sieve aperture size or wrap spacing is a sieve and cage design parameter that may vary for each feed to be processed by oleophilic sieve separation. Compared with prior art of the inventor, such as is detailed, for example, in US granted patent 10,399,008, B2 and Canadian pending patent 2.999,466 that did not use an effluent tank, the fact that the cage of the present invention is immersed in effluent allows for the use of oleophilic sieves of larger aperture size or for sieve wraps that can spread to allow larger size hydrophilic surface gravel to flow into the effluent tank while yet achieving high oleophilic phase recovery from the feed by the oleophilic sieve(s).
As soon as an oversize article has passed out of the cage by spreading adjacent wraps the wraps snap back to re-establish parallel adjacent wraps. This is not possible with metal belts that have a fixed opening size.
TEMPERATURE
Process temperature inside the cage is describes as cold and in the hot zone is described as warm or hot. It means that oleophilic sieve separation is a two temperature process with cage temperature influenced by the viscosity of oleophilic phase inside the cage and inside the hot zone for optimum separation efficiency. For example, when successfully processing tailings pond fluid fine tailings (FFT) by oleophilic sieve separation, the available feed year round temperature often was close to 12 degrees centigrade due to the depth of the ponds in spite of a thin ice covering at the top in winter time. The temperature in the hot zone was about 80 degrees C. for effective flow of oleophilic phase product from the sieve. For processing mined oil sand slurry the feed temperature during separation averaged close to 35 degrees centigrade. When processing FFT that contained centrifuge naphtha, oleophilic sieve separation of FFT
supplied by highway tankers improved in winter when feed temperature could be dropped close to 2 or 4 degrees centigrade above freezing to make the naphtha diluted bitumen adhere well in a thick layer to oleophilic rods or balls and oleophilic sieves. Naphtha diluted FFT became a thing of the past after naphtha recovery at centrifuge plants improved.
SUITABLE OLEOPHILIC SIEVES
When the oleophilic sieve is comprised of wraps of endless rope, the rope may be of twisted plastic strands, twisted carbon fiber strands or twisted metal strands, including steel wire strands when these have permanent oleophilic surfaces or when voids in the cable surface due to strand wrap are oleophilic. Braided ropes may be used but are not as suitable as twisted rope, since splices of braided ropes are larger in diameter than splices of twisted rope. When braided rope is used, the rakes that space the wraps of endless rope normally must be made to accept spliced braided rope. Twisted steel strand and plastic strand rope will tend to collect bitumen between its outside strands and on top of the strands to make it suitable to form oleophilic sieves of endless rope for use in the present invention.
Alternately, each external steel strand may be made to have an oleophilic surface. This oleophilic surface on each strand may wear off during operation but most will stay on the strand surfaces that do not contact abrading surfaces. Such strand surfaces also work well to collect oleophilic phase.
As many oil sand workers have discovered, pushing a steel shovel blade in room temperature oilsand ore will result in a bitumen coating on the shovel metal surface.
Similar adhesion of bitumen for metal surface cable tends to occur with metal conveyor belts and with steel cable, especially when some bitumen already is present in the valleys between strands of twisted cable.
Conventional open face metal conveyor belts, such as hinge oven belts or belts made with interlocking steel wire coils to form a conveyor may be used as oleophilic sieves. However, twisted endless plastic or metal rope sieves usually are preferred for optimum phase separation, since sieve wraps can be spaced closely to form a sieve of long narrow apertures for efficient collection of dispersed oleophilic phase leaving the cage for the effluent tank while allowing hydrophilic mineral particles to spread the wraps on their way to the effluent tank to prevent hydrophilic particulates from filling the cage and reducing separation efficiency. Such spreading is not possible with metal conveyer belts of fixed opening size.
FIELD ASSEMBLY

The cages and tanks detailed in Table Fig. 8 are very large in size to meet commercial equipment demand and will present some difficulty for highway or railway transport. For that reason the separator parts and pieces may be shop fabricated separately and assembled in the field. For example, the longitudinal structural members may be shop fabricated, cut to desired length, grooved, provided by rake, threaded for nuts on outside ends to accept nuts or drilled and tapped to accept bolts to mount to the cage end walls, or are welded on site to the end walls.
Similarly, the central shaft may be provided with keyway at both ends to accept a flange similar to a pipe flange but provided with a keyway to fit on the shaft, with both holes in the flange to be bolted to the cage end plates in the field. A
similar break down of tank parts fabricated in a shop may be used for assembly in the field for accepting the cage.
The 2 meter diameter cage and its effluent tank likely is the smallest useful commercial separator. It will likely be fabricated, assembled and offered for look/see demonstration purposes and time limited use by several oil sand operators or mineral mine owners.
PROCESSING FEED MIXTURES
Oleophilic sieve separation lends itself to separating mixtures of more than one feed. For example, screened mined oil sand, from which gravel has been removed, may be mixed for separation with water effluent of prior oleophilic sieve oil sand extraction, which has settled for months or even weeks to allow most mineral particulates to settle. Such use of prior used process water will reduce fresh water demand in a major way.
Mined, screened to remove hydrophilic oversize, oil sand may be mixed with existing old tailings pond fluid fine tailings to recover both fresh bitumen and old bitumen, reducing in a major way the need for fresh water and increasing total bitumen production.
Mined, screened to remove oversize, oil sand may be mixed with pH neutral (pH
between 6.8 and 7.2) settled process water of recent oil sand extractions after settling for a few weeks or months to prepare a feed for oleophilic sieve separation. This also reduces fresh water demand for separations.
Mine minerals may be separated using a mix of mine tailings pond water and fresh water using more pond water than fresh water for the mix when caustic is not used in the separations. In this case viscous oil is added to the feed to coat oleophilic mineral particles =
for cold adhesion the sieve surfaces.
Oleophilic sieve separation is tolerant of feed pH and hydrophilic minerals content of small size. Using neutral pH feed, where possible, simplifies separation and can reduce separation costs by allowing major reuse of process water after a period of minerals settling.What is claimed is:
1. An oleophilic sieve separation apparatus immersed in a cold effluent of separation tank suitable for separating: 1. mined oil sand slurries, 2. oil sand tailings pond fluid fine tailings, or 3. a mix of mined oil sand and tailings pond fluid fine tailings, in each case yielding a relatively cold water and hydrophilic minerals effluent and a relatively warm bitumen phase product, wherein a. the immersed in tank apparatus comprises a rotatable metal cage of two spaced disc type cage end walls, a central shaft projecting outward from both cage end walls and at least eight longitudinal structural members between end walls spaced equidistantly near cage wall circumference, b. distance between cage end walls inside faces is greater than cage end wall diameter, c. the cage central shaft is mounted in bearings supported at both ends by the tank and is provided with shaft seals to prevent liquid spillage out of the tank, d. at least one central shaft end of the cage extends well beyond end wall of the tank to allow slow driven rotation of the cage by gear box and motor, e. at least one endless oleophilic sieve comprising multiple wraps of oleophilic surface endless rope surrounds most of the cage circumference and is prevented from rolling off the cage by two pulleys which redirect a wrap about to roll off the end of the cage to the beginning of the cage, f. each rope wrap of oleophilic sieve is supported on the longitudinal structural members to form an incomplete polygon with corners at the longitudinal structural members and with sides that project into cage interior, g. during cage rotation the incomplete polygon rope wraps leave the cage to pass through a hot zone above and/or beside the tank to thereafter cool and return to the cage, h. rakes on at least alternate longitudinal structural members equally space the oleophilic wraps and provide friction for movement to the wraps due to cage rotation,

Claims (25)

What is claimed is:

1. An oleophilic sieve separation apparatus immersed in a cold effluent of separation tank suitable for separating: 1. mined oil sand slurries, 2. oil sand tailings pond fluid fine tailings, or 3. a mix of mined oil sand and tailings pond fluid fine tailings, in each case yielding a relatively cold water and hydrophilic minerals effluent and a relatively warm bitumen phase product, wherein a. the immersed in tank apparatus comprises a rotatable metal cage of two spaced disc type cage end walls, a central shaft projecting outward from both cage end walls and at least eight longitudinal structural members between end walls spaced equidistantly near cage wall circumference, b. distance between cage end walls inside faces is greater than cage end wall diameter, c. the cage central shaft is mounted in bearings supported at both ends by the tank and is provided with shaft seals to prevent liquid spillage out of the tank, d. at least one central shaft end of the cage extends well beyond end wall of the tank to allow slow driven rotation of the cage by gear box and motor, e. at least one endless oleophilic sieve comprising multiple wraps of oleophilic surface endless rope surrounds most of the cage circumference and is prevented from rolling off the cage by two pulleys which redirect a wrap about to roll off the end of the cage to the beginning of the cage, f. each rope wrap of oleophilic sieve is supported on the longitudinal structural members to form an incomplete polygon with corners at the longitudinal structural members and with sides that project into cage interior, g. during cage rotation the incomplete polygon rope wraps leave the cage to pass through a hot zone above and/or beside the tank to thereafter cool and return to the cage, h. rakes on at least alternate longitudinal structural members equally space the oleophilic wraps and provide friction for movement to the wraps due to cage rotation, i. one or more man holes with removable cover in at least one of the cage walls allow insertion of long oleophilic rods into the cage interior, j. one or more shelves each comprising at least two parallel straight or curved bars attached to at least one longitudinal structural member are provided inside the cage to allow assembly of rods on shelf and spillage of rods from shelf when the cage rotates, k. at least half of the cage circumference is void of shelves to allow oleophilic rods to roll along the bottom quadrant of the cage to contact incomplete polygon sieve wraps that project into cage interior, l. feed distributor or distributors mounted above the cage not covered by incomplete polygon sieve wraps allows entry of feed into the cage along cage length for separation at a rate controlled by valve, m. a control valve near the bottom of the tank allows rate of exit of effluent of separation flow leaving the tank to establish a difference in liquid level that is higher in the cage than in the tank, n. suitable gearing and/or electric phase motor control is provided to achieve a desired slow rate of cage rotation to thereby limit excessive turbulence inside the effluent tank while optimizing desired separation rate during operation, o. the oleophilic rods are almost as long as the inside distance between cage end walls and are prevented from leaving the cage during cage rotation.

2. The cage of Claim 1 wherein distance between rakes on longitudinal structural members is great enough to allow sieve wraps to be spread by hydrophilic mineral particles of the feed in size at least twice the normal distance between adjacent sieve wraps and crowd adjacent sieve wraps to allow such mineral particles to leave the cage for the effluent tank and wherein control of effluent removal from the tank is adapted to allow passage of said oversize mineral particles out of the tank.

3. The cage of Claim 1 wherein a short metal hoop is welded to each end wall inside face and to each longitudinal structural member to contain the oleophilic rods inside the cage and wherein each oleophilic rod is long enough to be so retained.

4. The cage of Claim 1 wherein metal flat bars, equal in number to the number of longitudinal structural members, are welded for a short distance to each longitudinal structural member and welded to each end wall inside face to contain the oleophilic rods inside the cage and wherein each oleophilic rod is long enough to be so retained.

5. The cage of Claim 1 wherein a hoop or multiple metal flat bars equal in number to the number of longitudinal structural members is or are attached to said members between adjacent oleophilic sieves when more than one oleophilic sieve is used on the cage, to space the sieves and to provide rigidity to longitudinal structural members, each connected between sieves to the hoop or metal flat bars.

6. The cage of Claim 1 containing a shelf of two or more straight bars between longitudinal structural member and cage central shaft.

7. The cage of Claim 1 containing a shelf of two or more curved bars between longitudinal structural member and cage central shaft.

8. The cage of Claim 1 containing several shelves of straight or curved bars each attached to longitudinal structural members of the cage.

9. The apparatus of Claim 1 wherein the oleophilic rods are closed end pipes or tubes almost as long as internal distance between end walls having an abrasion resistant oleophilic outside surface and are loaded, as needed, to a density suitably for settling slowly at a desired rate through feed inside the rotating cage after being collected on and released from shelf or shelves inside rotating cage.

10. The apparatus of claim 9 wherein the oleophilic rods are yellow jacket pipe or tube.

11. The apparatus of Claim 1 wherein each sieve of endless oleophilic rope is replaced by a metal conveyor belt of joined metal hinges or interlocking metal coils.

12. A method of separating the following feeds containing water, mineral particulates and bitumen: 1. mined oil sand slurries, 2. oil sand tailings pond fluid fine tailings, 3. a mix of mined oil sand and tailings pond fluid fine tailings, each introducing the feed for separation into a rotating cage immersed in a tank partly filled with effluent of separation wherein a) the cage is fabricated from two spaced steel disc type end walls, a strong central steel shaft that projects beyond the end walls and at least eight longitudinal structural members that are longer than end wall diameter between end walls equally spaced along and attached to end walls near end walls circumference, b) at least one manhole with cover is mounted in one or both end walls to allow insertion into the cage of a multitude of round oleophilic rods that are slightly shorter than inside distance between end walls, c) a short hoop of steel is welded to both end walls inside face and welded for a short distance to the outward facing surface of the longitudinal structural members to keep the oleophilic rods inside the cage when the cage rotates.
d) alternately, at least eight straight steel flat bars of limited width are welded between the at least eight longitudinal structural members and to the end walls inside faces to keep oleophilic rods inside the cage during cage rotation, e) at least one oleophilic sieve surrounds the bottom and sides and part of the top quadrant of the cage in the form of multiple wraps of endless rope supported on the longitudinal structural members, each wrap talking the form of an incomplete polygon with corners at the longitudinal structural members and with sides that project into the cage interior for contacting settled oleophilic rods, f) during operation and hence cage rotation, feed enters the cage from feed distributor(s) along the top of the cage not covered by oleophilic sieve wraps, g) shelf or shelves inside the rotating cage gather oleophilic rods to elevate these inside the rotating cage for subsequent spillage into and settling through feed inside the cage, h) while settling through feed inside the cage the oleophilic rods collect oleophilic phase from the feed inside the cage and after settling transfer it to the oleophilic sieve wraps that project into the cage interior along cage bottom quadrant, i) above the cage is a hot zone and the oleophilic sieve wraps revolving with the cage containing viscous oleophilic phase also revolve through a hot zone above the cage where heat causes viscosity reduction of the cold viscous oleophilic phase to yield a warm liquid product of oleophilic sieve separation, j) hydrophilic effluent of separation leaves the cage for the tank and while flowing from the cage into the tank passes through space between oleophilic sieve wraps surrounding the cage, releasing residual oleophilic phase to the wraps.

13. The method of Claim 12 wherein each shelf comprises at least two straight bars attached to a longitudinal structural member.

14. The method of Claim 12 wherein each shelf comprises at least two curved bars attached to a longitudinal structural member.

15. The method of Claim 12 wherein each shelf is also attached to the central shaft.

16. The method of Claim 12 wherein the rope wraps are made from one of the following materials, plastic, carbon fiber, steel or other metal and the surface of the rope wraps is oleophilic.

17. The method of Claim 12 for separating mined oil sand slurry from which oversize gravel has been removed.

18. The method of Claim 12 for separating a mixture of tailings pond fluid fine tailings and mined screened oil sand ore from which coarse gravel has been removed and water has been added as needed for effective oleophilic phase separation from hydrophilic phase by oleophilic sieve.

19. The method of Claim 12 for separating a water wet mineral ore mixture to which viscous hydrophilic phase has been added to coat oleophilic surface mineral for adhesion to oleophilic surface rods for transfer to oleophilic sieve wraps for removal, and enough water has been added to allow hydrophilic minerals to report to the effluent tank in passing through space between sieve wraps or though metal conveyor openings.

20. The method of Claim 12 wherein the feed is a mixture comprising water, sand or soil and mine minerals from mineral deposits to which water and a viscous hydrocarbon has been added to disperse the feed and to cover oleophilic mineral particle with viscous hydrocarbon to cause oleophilic mineral particle adherence to sieve surfaces.

21. The method of Claim 12 wherein the feed is a mixture of mined oil sand and tailings pond fluid fine tailings.

22. The method of Claim 12 wherein the feed has a pH between 6.8 and 7.2 and is a mixture of mined oil sand and tailings pond fluid fine tailings.

23. The method of Claim 12 wherein the feed is screened mined oil sand to remove oversize that cannot pass out of the cage into the effluent tank and wherein process water for separation is a mix of fresh water and used water from a previous oil sand extraction that has settled to reduce hydrophilic minerals content.

24. The method of Claim 12 wherein a feed of marine minerals and water is separated into oleophilic product and hydrophilic effluent by adding a viscous hydrocarbon liquid or paste to coat oleophilic minerals to the feed for adhesion to the oleophilic sieve(s)

25. The method of Claim 12 wherein the feed is screened mine minerals to remove all oversize particulates that cannot pass through oleophilic sieve apertures of the cage and with water and viscous hydrocarbon added to disperse minerals and coat oleophilic minerals with viscous hydrocarbon for adhesion to oleophilic sieve to separate the feed into oleophilic product and hydrophilic effluent or vice versa.