Note: Descriptions are shown in the official language in which they were submitted.
CA 02787798 2013-05-13 BITUMINOUS FROTH INCLINED PLATE SEPARATOR AND HYDROCARBON 2 CYCLONE TREATIVLENT PROCESS 3 Related Applications 4 This application is a divisional application of application serial number 2,761,345, which is a divisional application.of patent no. 2,471,048, which is a divisional application of 6 patent no. 2,400,258 filed September 19, 2002. 7 Field of the invention 8 This invention relates to bitumen recovery from oil sand and more particularly to a treatment 9 process for the removal of water and mineral from the product produced in a primPry oil sand ' 10 bitumen extraction process. 11 Background to the Invention 12 Oil sands are a geological formation, which are also known as tar sands or bituminous sands. 13 The oil sands deposits provide aggregates of solids such as sand, clay mineral plus water and 14 bitumen - a term for extra heavy oil. Significant deposits of oil sands are found in Northern Alberta in Canada and extend across an area of more than thirteen thousand square miles. The 16 oil sands formation extends from the surface or zero depth to depths of two thousand feet below 17 overburden. The oil sands deposits are measured in billions of barrels equivalent of oil and 18 represent a significant portion of the worldwide reserves of conventional and non-conventional 19 oil reserves. The oil sands deposits are composed primarily of particulate silica mineral material. The 21 bitumen content varies from about 5% to 21% by weight of the formation material, with atypical. 22 content of about 12% by weight. The mineral portion of the oil sands formations generally 23 includes clay and silt ranging from about 1% to 50% by -weight and more typically 10% to 30% 24 by weight as well as a small amount of water in quantities ranging between 1% and 10% by weight. The in-situ bitumen is quite viscous, generally has an API gravity of about 6 degrees to 26 8 degrees and typically includes 4% to 5% sulfur with approximately 38% aromatics. 214763E3.1 1 CA 02787798 2012-08-17 1 The Athabasca oil sands are bitumen-bearing sands, where the bitumen is isolated from the sand 2 by a layer of water forming a water-wet tar sand. Water-wet tar sand is almost unique to the 3 Athabasca oil sands and the water component is frequently termed connate water. Sometimes 4 the term water-wet is used to describe this type of tar sand to distinguish it from the oil-wet sand deposits found more frequently in other tar sand formations and in shale deposits including those 6 oily sands caused by oil spills. 7 The extraction of the bitumen from the sand and clay-like mineral material is generally 8 accomplished by heating the composition with steam and hot water in a rotating vessel or drum 9 and introducing an extraction agent or process aid. The process aid typically is sodium hydroxide NaOH and is introduced into the processing to improve the separation and recovery of 11 bitumen particularly when dealing with difficult ores. The hot water process is carried out in a 12 vessel called a separator cell or more specifically a primary separator vessel (PSV) after the oil 13 sand has been conditioned in the rotating drum. 14 The PSV process produces a primary bitumen froth gathered in a launder from the upper perimeter of the vessel; a mineral tailings output from the lower portion of the vessel and a 16 middlings component that is removed from the mid-portion of the vessel. It has been found that 17 production of the middlings component varies with the fines and clay content of the Originating 18 oil sand and is described more fully, for example in Canadian patent 857,306 to Dobson. The 19 middlings component contains an admixture of bitumen traces, water and mineral material in suspension. The middlings component is amenable to secondary separation of the bitumen it 21 contains, by introducing air into the process flow in flotation cells. The introduced air causes the 22 bitumen to be concentrated at the surface of the flotation cell. The flotation of the bitumen in 23 preference to the solids components permits the air entrained bitumen to be extracted from the 24 flotation cell. Flotation of the air-entrained bitumen from the process flow is sometimes termed differential flotation. The air-entrained bitumen froth is also referred to as secondary froth and is 26 a mixture of the bitumen and air that rises to the surface of the flotation cell. Typically, the 27 secondary froth may be further treated, for example by settling, and is recycled to the PSV for 28 reprocessing. 21476383.1 2 CA 02787798 2012-08-17 1 Further treatment of the primary bitumen froth from the PSV requires removal of the mineral solids, the water and the air from the froth to concentrate the bitumen content. Conventionally, 3 this is done by the use of centrifuges. Two types of centrifuge systems have heretofore been 4 deployed. One, called a solids-bowl centrifuge has been used to reduce the solids in froth substantially. To remove water and solids from the froth produced by a solids- bowl centrifuge; a 6 secondary centrifuge employing a disk has been used. Disk centrifuges are principally de- 7 watering devices, but they help to remove mineral as well. Examples of centrifuge systems that 8 have been deployed are described in Canadian patents 873,854; 882,667; 910,271 and 1,072,473. 9 The Canadian patent 873,854 to Baillie for example, provides a two-stage solid bowl and disk centrifuge arrangement to obtain a secondary bitumen froth from the middlings stream of a 11 primary separation vessel in the hot water bitumen recovery process. The Canadian patent 12 882,667 to Daly teaches diluting bitumen froth with a naphtha diluent and then processing the 13 diluted bitumen using a centrifuge arrangement. 14 Centrifuge units require an on-going expense in terms of both capital and operating costs. Maintenance costs are generally high with centrifuges used to remove water and solid minerals 16 from the bitumen froth. The costs are dictated by the centrifuges themselves, which are ,. 17 mechanical devices having moving parts that rotate at high speeds and have substantial 18 momentum. Consequently, by their very nature, centrifuges require a lot of maintenance and are 19 subject to a great deal of -wear and tear. Therefore, elimination of centrifuges from the froth treatment process would eliminate the maintenance costs associated with this form of froth 21 treatment. Additional operating cost results from the power cost required to generate the high g- 22 forces in large slurry volumes. 23 In the past, cyclones of conventional design have been proposed for bitumen froth treatment, for 24 example in Canadian patents 1,026,252 to Lupu1 and 2,088,227 to Gregoli. However, a basic problem is that recovery of bitumen always seems to be compromised by the competing 26 requirements to reject water and solids to tailings while maintaining maximum hydrocarbon 27 recovery. In practice, processes to remove solids and water from bitumen have been offset by 28 the goal of maintaining maximal bitumen recovery. Cyclone designs heretofore proposed tend to 29 allow too much water content to be conveyed to the overflow product stream yielding a poor bitumen-water separation. The arrangement of Lupul is an example of use of off- the-shelf 21473g3.1 3 CA 02787798 2012-08-17 1 cyclones that accomplish high bitumen recovery, unfortunately with low water rejection. The 2 low water rejection precludes this configuration from being of use in a froth treatment process, as 3 too much of the water in the feed stream is passed to the overflow or product stream. 4 A hydrocyclone arrangement is disclosed in Canadian patent 2,088,227 to Gregoli. Gregoli teaches alternative arrangements for cyclone treatment of non-diluted bitumen froth. The 6 hydrocyclone arrangements taught by Gregoli attempt to replace the primary separation vessel of 7 a conventional tar sand hot water bitumen processing plant with hydrocyclones. The process 8 arrangement of Gregoli is intended to eliminate conventional primary separation vessels by 9 supplanting them with a hydrocyclone configuration. This process requires an unconventional upgrader to process the large amounts of solids in the bitumen product produced by the apparatus 11 of Gregoli. Gregoli teaches the use of chemical additive reagents to emulsify high bituminous 12 slurries to retain water as the continuous phase of emulsion. This provides a low viscosity slurry 13 to prevent the viscous plugging in the hydrocyclones that might otherwise occur. Without this 14 emulsifier, the slurry can become oil-phase continuous, which will result in several orders of magnitude increase in viscosity. Unfortunately, these reagents are costly making the process 16 economically unattractive. 17 Another arrangement is disclosed in Canadian patent 2,029,756 to Sury, which describes an 18 apparatus having a central overflow conduit to separate extracted or recovered bitumen from a 19 froth fluid flow. The apparatus of Sury is, in effect, a flotation cell separator in which a feed material rotates about a central discharge outlet that collects a launder overflow. The 21 arrangement of Sury introduces process air to effect bitumen recovery and is unsuitable for use 22 in a process to treat deaerated naphtha-diluted-bitumen froth as a consequence of explosion 23 hazards present with naphtha diluents and air. 24 Other cyclone arrangements have been proposed for hydrocarbon process flow separation from gases, hot gases or solids and are disclosed for example in Canadian patents 1,318,273 to 26 Mundstock et al; 2,184,613 to Raterman et al and in Canadian published patent applications 27 2,037,856; 2,058,221; 2,108,521; 2,180,686; 2,263,691, 2,365,008 and the hydrocyclone 28 arrangements of Lavender et al in Canadian patent publications 2,358,805, 2,332,207 and 29 2,315,596. 21476383.1 4 CA 02787798 2012-08-17 1 2 Summary of the invention 3 In the following narrative wherever the term bitumen is used the term diluted bitumen is implied. 4 This is because the first step of this froth treatment process is the addition of a solvent or diluent such as naphtha to reduce viscosity and to assist hydrocarbon recovery. The term hydrocarbon 6 could also be used in place of the word bitumen for diluted bitumen. 7 The present invention provides a bitumen froth process circuit that uses an arrangement of 8 hydrocarbon cyclones and inclined plate separators to perform removal of solids and water from 9 the bitumen froth that has been diluted with a solvent such as naphtha. The process circuit has an inclined plate separator and hydrocarbon cyclone stages. A circuit configured in accordance with 11 the invention provides a process to separate the bitumen from a hybrid emulsion phase in a 12 bitumen froth. The hybrid emulsion phase includes free water and a water- in-oil emulsion and 13 the circuit of the present invention removes minerals such as silica sand and other clay minerals 14 entrained in the bitumen froth and provides the removed material at a tailings stream provided at a circuit tails outlet. The process of the invention operates without the need for centrifuge 16 equipment. The elimination of centrifuge equipment through use of hydrocarbon cyclone and 17 inclined plate separator equipment configured in accordance with the invention provides a cost 18 saving in comparison to a process that uses centrifuges to effect, bitumen de-watering and 19 demineralization. However, the process of the invention can operate with centrifuge equipment to process inclined plate separator underflow streams if so desired. 21 The apparatus of the invention provides an inclined plate separator (IPS) which operates to 22 separate a melange of water-continuous and oil-continuous emulsions into a cleaned oil product 23 and underflow material that is primarily a water-continuous emulsion. The cyclone apparatus 24 processes a primarily water-continuous emulsion and creates a product that constitutes a melange of water-continuous and oil-continuous emulsions separable by an IPS unit. When the apparatus 26 of the invention is arranged with a second stage of cyclone to process the underflow.of a first 27 stage cyclone, another product stream, separable by an LPS unit can be created along with a 28 cleaned tails stream. 21476383.1 5 CA 02787798 2012-08-17 = 1 -- In accordance with the invention, the bitumen froth to be treated is supplied to a circuit inlet for 2 -- processing into a bitumen product provided at a circuit product outlet and material removed from 3 -- the processed bitumen froth is provided at a circuit tails outlet. The bitumen froth is supplied to 4 -- a primary inclined plate separator (IPS) stage, which outputs a bitumen enhanced overflow -- stream and a bitumen depleted underflow stream. The underflow output stream of the first 6 -- inclined plate separator stage is a melange containing a variety of various emulsion components 7 -- supplied as a feed stream to a cyclone stage. The cyclone stage outputs a bitumen enhanced 8 -- overflow stream and a bitumen depleted underflow stream. The formation of a stubborn 9 -- emulsion layer can block the downward flow of water and solids resulting in poor bitumen -- separation. These stubborn emulsion layers are referred to as rag-layers. The process of the 11 -- present invention is resistant to rag-layer formation within the inclined plate separator stage, 12 -- which is thought to be a result of the introduction of a recycle feed from the overflow stream of 13 -- the hydrocarbon cyclone stage. 14 -- The material of the recycle feed is conditioned in passage through a hydrocarbon cyclone stage. -- When the recycle material is introduced into the inclined plate separator apparatus, a strong 16 -- upward bitumen flow is present even with moderate splits. Static deaeration, that is removal of 17 -- entrained air in the froth without the use of steam, is believed to be another factor that promotes 18 -- enhanced bitumen-water separation within the inclined plate separators. A bitumen froth that has 19 -- been deaerated without steam is believed to have increased free-water in the froth mixture -- relative to a steam deaerated froth., thus tending to promote a strong water flow in the underflo-w 21 -- direction, possibly due to increased free-water in the new feed. In a process arranged in 22 accordance with this invention distinct rag-layers are not manifested in the compression or 23 -- underflow zones of the EPS stages. 24 -- The underflow output stream of the first inclined plate separator stage is supplied to a primary -- hydrocarbon cyclone stage, which transforms this complex mixture into an emulsion that is 26 -- available from the primary cyclone stage as an overflow output stream. In a preferred 27 -- arrangement, the overflow output stream of the primary cyclone stage is supplied to an IPS stage 28 -- to process the emulsion. The overflow output stream of an TIPS stage provides a bitumen product 29 -- that has reduced the non-bitumen components in an effective manner. 214763E3.1 6 CA 02787798 2012-08-17 1 The hydrocarbon cyclone apparatus of the present invention has a long- body extending between 2 an inlet port and a cyclone apex outlet, to which the output underflow stream is directed, and an 3 abbreviated vortex finder to which the output overflow stream is directed. This configuration 4 permits the cyclone to reject water at a high percentage to the underflow stream output at the apex of the cyclone. This is accomplished in process conditions that achieve a high hydrocarbon 6 recovery to the overflow stream, which is directed to the cyclone vortex finder, while still 7 rejecting most of the water and minerals to the apex underflow stream. Mineral rejection is 8 assisted by the hydrophilic nature of the mineral constituents. The cyclone has a shortened or 9 abbreviated vortex finder, allowing bitumen to pass directly from the input bitumen stream of the cyclone inlet port to the cyclone vortex finder to which the output overflow stream is directed. 11 The long-body configuration of the cyclone facilitates a high water rejection to the apex 12 underflow. Thus, the normally contradictory goals of high hydrocarbon recovery and high 13 rejection of other components are simultaneously achieved. 14 The general process flow of the invention is to supply the underflow of an inclined plate separator stage to a cyclone stage. To have commercial utility, it is preferable for the cyclone 16 units to achieve water rejection. Water rejection is simply the recovery of water to the underflow 17 or reject stream. 18 In addition to the unique features of the hydrocarbon cyclone apparatus the process units of this 19 invention interact with each other in a novel arrangement to facilitate a high degree of constituent material separation to be achieved. The bitumen froth of the process stream 21 emerging as the cyclone overflow is conditioned in passage through the cyclone to yield over 22 90% bitumen recovery when the process stream is recycled to the primary inclined plate 23 separator stage for further separation. Remarkably, the resultant water rejection on a second pass 24 through the primary cyclone stage is improved over the first pass. These process factors combine to yield exceptional bitumen recoveries in a circuit providing an alternate staging of an 26 inclined plate separator stage and a cyclone stage where the bitumen content of the output 27 bitumen stream from the circuit exceeds 98.5% of the input bitumen content. Moreover, the 28 output bitumen stream provided at the circuit product outlet has a composition suitable for 29 upgrader processing. 21476383.1 7 CA 02787798 2013-05-13 1 In a further aspect of the present invention there is provided a system for processing a 2 bitumen feed comprising a mixture of bitumen, water and mineral. The system may 3 comprise: 4 a first separation stage comprising a first inclined plate separator operative to separate bitumen from the bitumen feed to produce a first overflow stream 6 and a first underflow stream, the first overflow stream comprising a first 7 bitumen enriched stream and the first underflow stream comprising a first 8 bitumen reduced stream; 9 a second separation stage comprising a first plurality of cyclones operative to separate bitumen from the first underflow stream to produce a second 11 overflow stream and a second underflow stream, the second overflow 12 stream comprising a second bitumen enriched stream and the second 13 underflow stream comprising a second bitumen reduced stream, wherein 14 each of the first plurality of cyclones comprises: a first cyclone body having a first elongated conical inner surface defining 16 a first cyclone cavity extending from a first upper inlet region with 17 a first diameter DC1 to a first lower apex outlet with a first 18 diameter DUI, wherein the first diameter DC1 is not less than about 19 150mm and not more than about 200mm and the first diameter DUI is not less than about 40mm and not more than about 50mm; 21 a first inlet forming a first inlet channel with a first diameter DI1 extending 22 into the first upper inlet region of the first cyclone cavity, wherein 23 the first inlet channel forms a first involute path into the first 24 cyclone cavity and the first diameter DI1 is approximately 50 mm or less; and 26 a first vortex finder forming a first overflow outlet of a first diameter DOI 27 extending into the first upper inlet region of the first cyclone cavity 28 toward the first lower apex outlet and having a first lower end 7a CA 02787798 2013-05-13 1 extending a first excursion distance below the first inlet channel, 2 wherein the first lower end of the first vortex finder within the first 3 cyclone cavity is disposed a first free vortex height (FV1-11) 4 distance from the first lower apex outlet and wherein the first diameter DOI is approximately 50mm or less and the first FV1-11 6 distance is not less than about 1133mm and not more than about 7 1821mm; 8 a third separation stage comprising a second plurality of cyclones operative to 9 separate bitumen from the second underflow stream to produce a third overflow stream and a third underflow stream, the third overflow stream 11 comprising a third bitumen enriched stream and the third underflow 12 stream comprising a third bitumen reduced stream; 13 a first diverter for diverting at least a first portion of the second overflow stream 14 to modulate modulating a composition of at least the first portion of the second overflow stream and the third overflow stream to form a first 16 recycle stream; and 17 a first recycling circuit for recycling the first recycle stream to the first separation 18 stage for further processing by the first inclined plate separator. 19 The system may further comprise a fourth separation stage operative to separate bitumen from at least a second portion of the second overflow stream to produce a fourth overflow 21 stream and a fourth underflow stream, the fourth overflow stream comprising a fourth 22 bitumen enriched stream and the fourth underflow stream comprising a fourth bitumen 23 reduced stream. 24 The fourth separation stage may comprise a second inclined plate separator. The fourth separation stage may comprise a first centrifuge for processing the second 26 portion of the second overflow stream. 7b CA 02787798 2013-05-13 I The system may further comprise a fifth separation stage operative to separate bitumen 2 from at least a third portion of the second overflow stream to produce a fifth overflow 3 stream and a fifth underflow stream, the fifth overflow stream comprising a fifth bitumen 4 enriched stream and the fifth underflow stream comprising a fifth bitumen reduced stream. 6 The fifth separation stage may comprise a second centrifuge for processing the third 7 portion of the second overflow stream. 8 The first overflow stream may comprise a first diluted bitumen product stream. 9 The fourth overflow stream may comprise a second diluted bitumen product stream. The fifth overflow stream may comprise a third diluted bitumen product stream. 11 The third underflow stream may form a first tailings stream. 12 The fifth underflow stream may form a second tailings stream. 13 The third bitumen reduced stream may have less bitumen than the first bitumen reduced 14 stream. The third bitumen reduced stream may have less bitumen that the second bitumen 16 reduced stream. 17 The third bitumen reduced stream may have less bitumen that the fourth bitumen reduced 18 stream. 19 The first bitumen reduced stream may have more bitumen than the second bitumen reduced stream. 21 The first bitumen reduced stream may have more bitumen than the fourth bitumen 22 reduced stream. 23 The solvent may comprise a paraffinic solvent. 24 The solvent may comprise naphtha. 7c CA 02787798 2013-05-13 1 The first diluted bitumen product stream may comprise approximately 34% or more 2 solvent by weight. 3 The first diluted bitumen product stream may comprise approximately 2.1% or less water 4 by weight. The first diluted bitumen product stream may comprise approximately 97% or more 6 hydrocarbon by weight. 7 The first diluted bitumen product stream may comprise approximately 1.2% or less solids 8 by weight. 9 The first and second diluted bitumen product streams in combination may comprise approximately 34% or more solvent by weight, approximately 2.1% or less water by 11 weight, approximately 97% or more hydrocarbon by weight and approximately 1.2% or 12 less solids by weight. 13 The first, second and third diluted bitumen product streams in combination may comprise 14 approximately 34% or more solvent by weight, approximately 2.1% or less water by weight, approximately 97% or more hydrocarbon by weight and approximately 1.2% or 16 less solids by weight. 17 The bitumen feed may comprise a hybrid emulsion phase comprising a mélange of water- 18 continuous and oil-continuous emulsions. 19 The first underflow stream comprises a water-continuous emulsion. The bitumen feed may comprise a bitumen froth formed by an oil sands extraction 21 process. 22 In a further aspect of the system, each of the second plurality of cyclones may comprise: 23 a second cyclone body having a second elongated conical inner surface defining a 24 second cyclone cavity extending from a second upper inlet region with a second diameter DC2 to a second lower apex outlet with a second diameter 7d CA 02787798 2013-05-13 1 DU2, wherein the second diameter DC2 is not less than about 150mm and 2 not more than about 200mm and the second diameter DU2 is not less than 3 about 40mm and not more than about 50mm; 4 a second inlet forming a second inlet channel with a second diameter DI2 extending into the second upper inlet region of the second cyclone cavity, 6 wherein the second inlet channel forms a second involute path into the 7 second cyclone cavity and the second diameter DI,' is approximately 50 8 mm or less; and 9 a second vortex finder forming a second overflow outlet of a second diameter DO2 extending into the second upper inlet region of the second cyclone 11 cavity toward the second lower apex outlet and having a second lower end 12 extending a second excursion distance below the second inlet channel, 13 wherein the second lower end of the second vortex finder within the 14 second cyclone cavity is disposed a second free vortex height (FV1-17) distance from the second lower apex outlet and wherein the second 16 diameter DO2 is approximately 50mm or less and the second FVH2 17 distance is not less than about 1133mm and not more than about 1821mm. 18 The system may further comprise a portion of the bitumen in the second underflow 19 stream that passes through the second inlet channel of at least one of the second plurality of cyclones exits the at least one of the second plurality of cyclones as part of the third 21 overflow stream without having to make a spiral journey down the second cyclone cavity. 22 The portion of the bitumen in the second undertlow stream may exit the at least one of 23 the second plurality of cyclones through the second overflow outlet after one and one half 24 revolutions. The second inlet channel may be shaped such that a diameter of the second involute path 26 of the second inlet channel narrows along the second involute path as the second inlet 27 channel approaches a central location proximate the second vortex finder. 7e CA 02787798 2013-05-13 1 The system may further comprise a reflection of a second descending helix vortex fluid 2 flowing into a second ascending helix vortex fluid flow forms in a central zone near the 3 second lower apex outlet of the second cyclone cavity. 4 The system may further comprise a second central vapour core extending along an axis of the second cyclone body. 6 The second central vapour core may be only millimeters in diameter and is sized 7 sufficiently to cause about 3% to about 4% enrichment in a solvent to bitumen ratio of the 8 third overflow stream. 9 The system may further comprise a portion of the bitumen in the first underflow stream that passes through the first inlet channel of at least one of the first plurality of cyclones 11 exits the at least one of the first plurality of cyclones as part of the second overflow 12 stream without having to make a spiral journey down the first cyclone cavity. 13 The portion of the bitumen in the first underflow stream may exit the at least one of the 14 first plurality of cyclones through the first overflow outlet after one and one half revolutions. 16 The first inlet channel may be shaped such that a diameter of the first involute path of the 17 first inlet channel narrows along the first involute path as the first inlet channel 18 approaches a central location proximate the first vortex finder. 19 The system may further comprise a reflection of a first descending helix vortex fluid flow into a first ascending helix vortex fluid flow forms in a central zone near the first lower 21 apex outlet of the first cyclone cavity. 22 The system may further comprise a first central vapour core extending along an axis of 23 the first cyclone body. 24 The first central vapour core may be only millimeters in diameter and is sized sufficiently to cause about 3% to about 4% enrichment in a solvent to bitumen ratio of the second 26 overflow stream. 7f CA 02787798 2013-05-13 1 In a further aspect of the present invention there is provided a method for processing a 2 bitumen feed comprising a mixture of bitumen, water and mineral. The method may 3 comprise: 4 separating bitumen from the bitumen feed with a first inclined plate separator to produce a first overflow stream and a first underflow stream, the first 6 overflow stream comprising a first bitumen enriched stream and the first 7 underflow stream comprising a first bitumen reduced stream; 8 separating bitumen from the first underflow stream with a first plurality of 9 cyclones to produce a second overflow stream and a second underflow stream, the second overflow stream comprising a second bitumen enriched 11 stream and the second underflow stream comprising a second bitumen 12 reduced stream, wherein each of the first plurality of cyclones comprises: 13 a first cyclone body having a first elongated conical inner surface defining 14 a first cyclone cavity extending from a first upper inlet region with a first diameter DC1 to a first lower apex outlet with a first 16 diameter DUI, wherein the first diameter DC1 is not less than about 17 150mm and not more than about 200mm and the first diameter 18 DUI is not less than about 40mm and not more than about 50mm; 19 a first inlet forming a first inlet channel with a first diameter DI1 extending into the first upper inlet region of the first cyclone cavity, wherein 21 the first inlet channel forms a first involute path into the first 22 cyclone cavity and the first diameter Dl1 is approximately 50 mm 23 or less; and 24 a first vortex finder forming a first overflow outlet of a first diameter DO extending into the first upper inlet region of the first cyclone cavity 26 toward the first lower apex outlet and having a first lower end 27 extending a first excursion distance below the first inlet channel, 28 wherein the first lower end of the first vortex finder within the first 7g CA 02787798 2013-05-13 1 cyclone cavity is disposed a first free vortex height (FV.Fli) 2 distance from the first lower apex outlet and wherein the first 3 diameter DOI is approximately 50mm or less and the first FV1-11 4 distance is not less than about 1133mm and not more than about 1821mm; 6 separating bitumen from the second underflow stream with a second plurality of 7 cyclones to produce a third overflow stream and a third underflow stream, 8 the third overflow stream comprising a third bitumen enriched stream and 9 the third underflow stream comprising a third bitumen reduced stream; modulating a composition of at least a first portion of the second overflow stream 11 and the third overflow stream to form a first recycle stream; and 12 recycling the first recycle stream to the first inclined plate separator for further 13 processing. 14 The method may further comprise separating bitumen from at least a second portion of the second overflow stream with a fourth separator to produce a fourth overflow stream 16 and a fourth underflow stream, the fourth overflow stream comprising a fourth bitumen 17 enriched stream and the fourth underflow stream comprising a fourth bitumen reduced 18 stream. 19 The fourth separator may comprise a second inclined plate separator. The fourth separator may comprise a first centrifuge for processing the second portion of 21 the second overflow stream. 22 The method may further comprise diverting the second overflow stream between the first 23 recycle stream and the fourth separator. 24 The method may further comprise separating bitumen from at least a third portion of the second overflow stream with a fifth separator to produce a fifth overflow stream and a 26 fifth underflow stream, the fifth overflow stream comprising a fifth bitumen enriched 27 stream and the fifth underflow stream comprising a fifth bitumen reduced stream. 7h CA 02787798 2013-05-13 I The fifth separator may comprise a second centrifuge for processing the third portion of 2 the second overflow stream. 3 The method may further comprise diverting the second overflow stream among the first 4 recycle stream, the fourth separator and the fifth separator. The method may further comprise modulating a composition of the second underflow 6 stream and the fourth underflow stream to form a first combined stream for processing by 7 the third separation stage. 8 The method may further comprise modulating a composition of the first recycle stream 9 and the bitumen feed to form a second combined stream for processing by the first inclined plate separator. 11 The first overflow stream may comprise a first diluted bitumen product stream. 12 The fourth overflow stream may comprise a second diluted bitumen product stream. 13 The fifth overflow stream may comprise a third diluted bitumen product stream. 14 The third underflow stream may form a first tailings stream. The fifth underflow stream may form a second tailings stream. 16 The third bitumen reduced stream may have less bitumen than the first bitumen reduced 17 stream. 18 The third bitumen reduced stream may have less bitumen that the second bitumen 19 reduced stream. The third bitumen reduced stream may have less bitumen that the fourth bitumen reduced 21 stream. 22 The first bitumen reduced stream may have more bitumen than the second bitumen 23 reduced stream. 7i CA 02787798 2013-05-13 I The first bitumen reduced stream may have more bitumen than the fourth bitumen 2 reduced stream. 3 The method may further comprise diluting the bitumen feed with a solvent. 4 The solvent may comprise a paraffinic solvent. The solvent may comprise naphtha. 6 The first diluted bitumen product stream may comprise approximately 34% or more 7 solvent by weight. 8 The first diluted bitumen product stream may comprise approximately 2.1% or less water 9 by weight. The first diluted bitumen product stream may comprise approximately 97% or more 11 hydrocarbon by weight. 12 The first diluted bitumen product stream may comprise approximately 1.2% or less solids 13 by weight. 14 The first and second diluted bitumen product streams in combination may comprise approximately 34% or more solvent by weight, approximately 2.1% or less water by 16 weight, approximately 97% or more hydrocarbon by weight and approximately 1.2% or 17 less solids by weight. 18 The first, second and third diluted bitumen product streams in combination may comprise 19 approximately 34% or more solvent by weight, approximately 2.1% or less water by weight, approximately 97% or more hydrocarbon by weight and approximately 1.2% or 21 less solids by weight. 22 The bitumen feed may comprise a hybrid emulsion phase comprising a mélange of water- 23 continuous and oil-continuous emulsions. 24 The first underflow stream may comprise a water-continuous emulsion. 7j CA 02787798 2013-05-13 1 The bitumen feed may comprise a bitumen froth formed by an oil sands extraction 2 process. 3 In a further aspect of the method, each of the second plurality of cyclones used to 4 separate bitumen from the second underflow stream may comprise: a second cyclone body having a second elongated conical inner surface defining a 6 second cyclone cavity extending from a second upper inlet region with a 7 second diameter DC2 to a second lower apex outlet with a second diameter 8 DU2, wherein the second diameter DC2 is not less than about 150mm and 9 not more than about 200mm and the second diameter DU2 is not less than about 40mm and not more than about 50mm; 11 a second inlet forming a second inlet channel with a second diameter DI2 12 extending into the second upper inlet region of the second cyclone cavity, 13 wherein the second inlet channel forms a second involute path into the 14 second cyclone cavity and the second diameter DI2 is approximately 50 mm or less; and 16 a second vortex finder forming a second overflow outlet of a second diameter 17 DO2 extending into the second upper inlet region of the second cyclone 18 cavity toward the second lower apex outlet and having a second lower end 19 extending a second excursion distance below the second inlet channel, wherein the second lower end of the second vortex finder within the 21 second cyclone cavity is disposed a second free vortex height (FVFI-)) 22 distance from the second lower apex outlet and wherein the second 23 diameter DO2 is approximately 50mm or less and the second 17VH2 24 distance is not less than about 1133mm and not more than about 1821mm. The method may further comprise causing a portion of the bitumen in the second 26 underflow stream that passes through the second inlet channel of at least one of the 27 second plurality of cyclones to exit the at least one of the second plurality of cyclones as 7k CA 02787798 2013-05-13 I part of the third overflow stream without having to make a spiral journey down the 2 second cyclone cavity. 3 The method may further comprise causing the portion of the bitumen in the second 4 underflow stream to exit the at least one of the second plurality of cyclones through the second overflow outlet after one and one half revolutions. 6 The second inlet channel may be shaped such that a diameter of the second involute path 7 of the second inlet channel narrows along the second involute path as the second inlet 8 channel approaches a central location proximate the second vortex finder. 9 The method may further comprise causing a reflection of a second descending helix vortex fluid flow into a second ascending helix vortex fluid flow to form in a central zone 11 near the second lower apex outlet of the second cyclone cavity. 12 The method may further comprise a second central vapour core extending along an axis 13 of the second cyclone body. 14 The second central vapour core may be only millimeters in diameter and is sized sufficiently to cause about 3% to about 4% enrichment in a solvent to bitumen ratio of the 16 third overflow stream. 17 The method may further comprise causing a portion of the bitumen in the first underflow 18 stream that passes through the first inlet channel of at least one of the first plurality of 19 cyclones to exit the at least one of the first plurality of cyclones as part of the second overflow stream without having to make a spiral journey down the first cyclone cavity. 21 The method may further comprise causing the portion of the bitumen in the first 22 underflow stream to exit the at least one of the first plurality of cyclones through the first 23 overflow outlet after one and one half revolutions. 24 The first inlet channel may be shaped such that a diameter of the first involute path of the first inlet channel narrows along the first involute path as the first inlet channel 26 approaches a central location proximate the first vortex finder. 71 CA 02787798 2013-05-13 1 The method may further comprise causing a reflection of a first descending helix vortex 2 fluid flow into a first ascending helix vortex fluid flow to form in a central zone near the 3 first lower apex outlet of the first cyclone cavity. 4 The method may further comprise a first central vapour core extendingalong an axis of the first cyclone body. 6 The first central vapour core may be only millimeters in diameter and is sized sufficiently 7 to cause about 3% to about 4% enrichment in a solvent to bitumen ratio of the second 8 overflow stream. 9 In a further aspect of the present invention, there is provided system for processing a bitumen feed comprising bitumen, water and mineral. The system may comprise: 11 a first separation stage comprising an inclined plate separator configured to receive 12 the bitumen feed and separate bitumen from the bitumen feed to produce a 13 first bitumen enriched stream and a first bitumen reduced stream; 14 a second separation stage comprising a first plurality of cyclones configured to receive the first bitumen reduced stream from the inclined plate separator and 16 to separate bitumen from the first bitumen reduced stream to produce a second 17 bitumen enriched stream and a second bitumen reduced stream; 18 a third separation stage configured to separate bitumen from the second bitumen 19 enriched stream to produce a third bitumen enriched stream and a third bitumen reduced stream; and 21 a diverter configured to optionally direct the second bitumen enriched stream to the 22 first separation stage for further processing by the first inclined plate separator 23 or to the third separation stage. 24 The system may further comprise a fourth separation stage configured to separate 26 bitumen from the second bitumen enriched stream to produce a fourth bitumen 27 enriched stream and a fourth bitumen reduced stream. 28 7m CA 02787798 2013-05-13 The method may further comprise separating bitumen from the second bitumen 2 enriched stream at a fourth separation stage to produce a fourth bitumen enriched 3 stream and a fourth bitumen reduced stream. 4 The method may further comprise separating bitumen from the second bitumen 6 reduced stream at a fifth separation stage to produce a fifth bitumen enriched stream 7 and a fifth bitumen reduced stream. 8 9 The third separation stage may comprise a centrifuge configured to produce the third bitumen enriched stream and the third bitumen reduced stream. 11 12 The third separation stage may comprise a second inclined plate separator configured 13 to produce the third bitumen enriched stream and the third bitumen reduced stream. 14 The fourth separation stage may comprise a centrifuge configured to produce the third 16 bitumen enriched stream and the third bitumen reduced stream. 17 18 The method may further comprise optionally diverting the second bitumen enriched 19 stream to the fourth separation stage. 7o CA 02787798 2012-08-17 I Other aspects and features of the present invention will become apparent to those ordinarily 2 skilled in the art upon review of the following description of specific embodiments of the 3 invention in conjunction with the accompanying figures. 4 Brief description of the Drawings Figure 1 is a schematic diagram depicting a preferred arrangement of apparatus adapted to carry 6 out the process of the invention. 7 Figure 2 is an elevation cross-section view of a preferred embodiment of a cyclone. 8 Figure 3 is a top cross-section view of the cyclone of Figure 2. 9 Figure 3a is an enlarged cross-section view of a portion of an operating cyclone. Figure 4 is a schematic diagram depicting another preferred arrangement of apparatus adapted to 11 carry out the process of the invention. 12 Detailed Description of the Invention 13 Figure 1 is a schematic diagram depicting the arrangement of apparatus adapted to carry out the 14 process of the invention. The schematic diagram provides an outline of the equipment and the process flows, but does not include details, such as pumps, that provide the ability to transport 16 the process fluids from one unit to the next. The apparatus of the invention includes inclined 17 plate separator (IPS) stage units and cyclone stage units, each of which process an input stream 18 to produce an overflow output stream, and an underflow output stream. The IPS overflow output 19 stream has a bitumen enriched content resulting from a corresponding decrease in solids, fines and water content relative to the bitumen content of the EPS input stream. The IPS underflow 21 output stream has solids, fines and water with a depleted bitumen content relative to the IPS 22 input stream. The IPS underflow output stream may be referred to as a bitumen depleted stream. 23 The cyclone stage overflow output stream has a bitumen enriched content resulting from a 24 corresponding decrease in solids, fines and water content relative to the bitumen content of the cyclone input stream. The cyclone underflow output stream has solids, fines and water with a 26 depleted bitumen content relative to the cyclone input stream. The cyclone underflovv output 27 stream may be referred to as a bitumen depleted stream. 214763E3.1 8 CA 02787798 2012-08-17 = 1 While the process flows and apparatus description of the invention made with reference to Figure 2 1 refers to singular units, such as a cyclone 16 or 28, a plurality of cyclone units are used in each 3 stage where process scale requires. For example, for production rates in excess of 200,000 4 bbl/day of bitumen, cyclone units are arranged in parallel groups of 30 or more with each cyclone unit bearing about 200 gal/rain of flow. In the general arrangement of the apparatus 6 adapted to carry out the process, inclined plate separator (IPS) units are alternately staged with 7 cyclone units such that an IPS stage underflow feeds a cyclone stage, while a cyclone stage 8 overflow feeds an IPS stage. The mutual conditioning of each stage contributes to the 9 remarkable constituent separation performance obtained by the unit staging of this process. The processing circuit has a circuit inlet 10 to receive a process feed stream 48. The process 11 feed stream is a bitumen froth output of an oil sands extraction process and is diluted at 11 with a 12 suitable solvent, for example naphtha, or a paraffinic or alkane hydrocarbon solvent. Naphtha is 13 a mixture of aromatic hydrocarbons that effectively dissolves the bitumen constituent of the 14 bitumen froth feed stream 48 supplied via line 10 to produce bitumen froth with a much-reduced viscosity. The addition of a solvent partially liberates the bitumen from the other components of 16 the bitumen froth feed stream 48 by reducing interfacial tensions and rendering the composition 17 more or less miscible. The diluted bitumen feed stream 50 including a recycle stream 57 is 18 supplied to a primary IPS stage comprising IPS units 12 and 14 shown as an example of multiple 19 units in a process stage. The overflow output stream 52 of the primary IPS stage is supplied as a product stream, which is sent to the circuit product outlet line 42 for downstream processing, for 21 example at an up grader plant. 22 The underflow output stream of the primary IPS stage is supplied via line 30 as the feed stream 23 68 to a primary hydrocarbon cyclone stage (HCS) comprising for example, a primary cyclone 16. 24 The hydrocarbon cyclone processes a feed stream into a bitumen enriched overflow stream and a bitumen depleted underflow stream. The overflow output stream 56 of the primary cyclone stage 26 on line 18 is directed for further processing depending on the setting of diverter valve 34. 27 Diverter valve 34 is adjustable to direct all or a portion of the primary HCS overflow output 28 stream 56 to a recycle stream 60 that is carried on line 24 to become recycle stream 57 or a part 29 of it. Recycle stream 57 is supplied to the primary IPS stage. The portion of the primary HCS overflow output stream that is not directed to recycle stream 60 becomes the secondary EPS feed 21476383.1 9 CA 02787798 2012-08-17 1 stream 58 that is delivered to a secondary IPS stage 22 via line 20. Naturally diverter valve 34 2 can be set to divert the entire HCS overflow stream 56 to the secondary PS feed stream 58 to the 3 limit of the secondary IPS capacity. 4 The circuit bitumen froth feed stream 48 will have varying quantities or ratios of constituent components of bitumen, solids, fmes and water. The quantities or ratios of the component of 6 froth feed stream 48 will vary over the course of operation of the circuit depending on the 7 composition of the in situ oil sands ore that are from time to time being mined and processed. 8 Adjustment of diversion valve 34 permits the processing circuit flows to be adjusted to 9 accommodate variations in oil sands ore composition, which is reflected in the composition of the bitumen froth feed stream 48. In this manner, the circuit process feed flow 50 to the primary 11 cyclone stage can be set to adapt to the processing requirements providing optimal processing for 12 the composition of the bitumen froth feed. In some circumstances, such as when the capacity of 13 the secondary IPS stage 22 is exceeded, all or a portion of the primary cyclone stage overflow 14 stream 56 on line 18 is directed to recycle stream 60 by diverter valve 34. Recycle stream 60 is carried on line 24 to form part of the recycle stream 57 supplied to the primary IPS stage IPS 16 units 12 and 14. However, the composition of stream 48 is nearly invariant to the composition of 17 mine run ore over a wide range of ores that might be fed to the upstream extraction process. 18 The preferred embodiment of a process circuit in accordance with the principles of the invention 19 preferably includes secondary IPS processing equipment interconnecting with the primary processing equipment by means of diverter valve 34. Where the entire overflow output stream of 21 the primary stage is recycled back to the prinary EPS stage, the primary IPS stage process acts as 22 a secondary 1PS stage and no stream is supplied to the secondary IPS stage for processing. 23 However, a secondary PS stage is preferably provided to accommodate the variations in 24 composition of the feed froth stream 48 encountered in operation of the process. Secondary PS unit 22 processes the feed stream 58 received from the overflow of the primary cyclone stage 26 into a bitumen enriched secondary IPS overflow output stream on line 32 and a bitumen depleted 27 secondary IPS underflow output stream 59 on line 26. The recovered bitumen of the secondary 28 IPS overflow stream on line 32 is combined with the overflow stream of the primary PPS stage to 29 provide the circuit output bitumen product stream 52 delivered to the circuit product outlet line 42 for downstream processing and upgrading. 214763E3 10 CA 02787798 2012-08-17 1 The secondary stage PS 22 underflow output stream 59 is supplied by line 26 where it is 2 combined with the primary cyclone underflow stream 61 to provide a feed stream 62 to a 3 secondary stage cyclone 28. The secondary hydrocarbon cyclone stage (HCS) 28 processes 4 input feed stream 62 into a bitumen enriched secondary HCS overflow output stream 64 on line 40 and a bitumen depleted secondary HCS underflow output stream 66 on line 36. The 6 secondary HCS underflow output stream 66 is directed to a solvent recovery unit 44, which 7 processes the stream to produce the circuit tailings stream 54 provided to the circuit tails outlet 8 46 of the circuit. The operating process of the secondary HCS 28 is varied during the operation 9 of the process. The operating process of the secondary HCS 28 is optimized to reduce the bitumen content of the secondary HCS underflow output stream 66 to achieve the target bitumen 11 recovery rate of the process. Preferably, the operation of the secondary HCS is maintained to 12 achieve a hydrocarbon content in the secondary HCS underflow output stream 66 that does not 13 exceed 1.6%. Preferably, a solvent recovery unit 44 is provided to recover diluent present in the 14 secondary HCS underflow output stream 66. Solvent recovery unit (SRI.T) 44 is operated to maintain solvent loss to the tailings stream 54 below 0.5% to 0.7% of the total solvent fed to the 16 circuit on line 11. The tailings stream 54 is sent for disposal on the circuit tails outlet line 46. 17 The primary and secondary HCS cyclone units achieve a so-called ternary split in which a high 18 hydrocarbon recovery to the output overflow stream is obtained with a high rejection of solids 19 and water reporting to the output underflow stream. In a ternary split, even the fines of the solids are rejected to a respectable extent. 21 The primary HCS cyclone unit 16 receives the underflow output stream on line 30 from the 22 primary IPS stage IPS units 12, 14 as an input feed stream 68. The primary hydrocarbon cyclone 23 16 processes feed stream 68 to obtain what is referred to herein as a ternary split. The = 24 hydrocarbon and other constituents of the cyclone feed stream are reconstituted by the hydrocarbon cyclone 16 so as to enable the primary HCS overflow output stream on line 18 to be 26 supplied, via line 20, as a feed stream 58 to a secondary TIPS stage unit 22. This process flow 27 obtains a ternary split, which achieves a high bitumen recovery. The process within primary 28 HCS cyclone unit 16 involves a complex transformation or re- conditioning of the received 29 primary TIPS undernow output stream 68. The primary HCS underflow output stream 61 is passed via line 38 to become part of the feed stream 62 of secondary HCS cyclone unit 28 and 2147633.I 11 CA 02787798 2012-08-17 1 yield further bitumen recovery. Further bitumen recovery from the secondary HCS overflow 2 output stream 64 is obtained by recycling that stream on line 40 back to the primary IPS stage for 3 processing. 4 The closed loop nature of the recycling of this process reveals an inner recycling loop, which is closed through line 26 from the secondary IPS stage and an outer recycling loop, which is closed 6 through line 40 from the secondary HCS. These recycle loops provide a recycle stream 57 which 7 contains material from the primary and secondary HCS and the bitumen recovered from this 8 recycle material is called second-pass bitumen. Remarkably the second- pass bitumen in recycle 9 stream 57 is recovered in the primary IPS stage at greater than 90% even though the bitumen did not go to product in the first pass through the primary IPS stage. Thus, the arrangement provides 11 a cyclic process in which the overflow stream of a HCS is reconditioned by an IPS stage and the 12 underflow stream of an IPS stage is reconditioned by a HCS. In this way, the individual process 13 stages recondition their overflow streams in the case of cyclone stages and their underflow 14 streams in the case of IPS stages for optimal processing by other downstream stages in the process loops. In the HCS cyclone units, the flow rates and pressure drops can be varied during 16 operation of the circuit. The HCS unit flow rates and pressure drops are maintained at a level to 17 achieve the performance stated in Tables 1 and 2. An input stream of a cyclone is split to the 18 overflow output stream and the underflow output stream and the operating flow rates and 19 pressure drops will determine the split of the input stream to the output streams. Generally, the range of output overflow split will vary between about 50% to about 80% of the input stream by 21 varying the operating flow rates and pressure drops. 22 Table 1 provides example compositions of various process streams in the closed-loop operation 23 of the circuit. Table 1 Bitume Minera Coars Hydrocarbo Stream Water Solvent Fines 1 48 New 55.00 8.50 36.50 00.00 3.38 5.12 55.00 feed 21476353.1 12 CA 02787798 2012-08-17 50 EPS feed 34.95 5.95 41.57 17.52 2.17 3.78 52.48 52 Product 63.51 0.57 2.06 33.86 0.00 0.57 97.37 54 Tails 1.02 17.59 80.98 0.59 7.42 10.17 1.61 1 2 Table 2 lists process measurements taken during performance of process units arranged in 3 accordance with the invention. In the table, the Bitumen column is a hydrocarbon with zero 4 solvent. Accordingly, the Hydrocarbon column is the sum of both the Bitumen and Solvent columns. The Mineral column is the sum of the Coarse and the Fines columns. These data are 6 taken from a coherent mass balance of operational data collected during demonstration and 7 operational trials. From these trials it was noted that water rejection on the HCS is over 50%. It 8 was also noted that the nominal recovery of IPS stage is about 78%, but was boosted to over 9 85% by the recycle. All of the stages in the circuit operate in combination to produce a recovery of bitumen approaching 99% and the solvent losses to tails are of the order of 0.3%. Table 2 Unit Operations Performance of Hydrocarbon Cyclones and Inclined Plate Separators in Closed Loop Unit Process Unit Unit Water Unit Solids Fines Rejection Hydrocarbon Rejection Rejection Recovery Primary IFS 78% 98% 97% Primary 85% 55% 78% Cyclone Secondary 85% 54% 82% Cyclone Recycle or 91% 98.5% 95.5% Secondary IFS Overall 99.2% Bitumen , Recovery 99.7% Solvent 21476383,1 13 CA 02787798 2012-08-17 Product Spec 2.0% H20 0.57% Mineral 0.32% non- bituminous hydrocarbon (NBHC) 1 2 Figure 2 shows an elevation cross-section of a preferred embodiment of the hydrocarbon cyclone 3 apparatus depicting the internal configuration of the cyclone units. The cyclone 70 defines an 4 elongated conical inner surface 72 extending from an upper inlet region 74 to an outlet underflow outlet 76 of lower apex 88. The cyclone has an upper inlet region 74 with an inner 6 diameter DC and an upper overflow outlet 84 of a diameter DO at the vortex finder 82 and an 7 underflow outlet 76 at the lower apex, which has a diameter DU. The effective underflow outlet 8 diameter 76 at the lower apex 88 of the cyclone is also referred to as a vena cava. It is somewhat 9 less than the apex diameter due to the formation of an up-vortex having a fluid diameter called the vena cava. The fluid flows near the lower apex 88 of a cyclone are shown in Figure 3a. The 11 cyclone has a free vortex height FVH extending from the lower end 92 of the vortex finder to the 12 vena cava of the lower apex 88. The fluid to be treated is supplied to the cyclone via input 13 channel 78 that has an initial input diameter DI. The input channel 78 does not need to have a 14 uniform cross-section along its entire length from the input coupling to the cyclone inlet 80. The fluid to be treated is supplied under pressure to obtain a target velocity within the cyclone when 16 the fluid enters the cyclone through cyclone inlet SO. Force of gravity and the velocity pressure 17 of the vortex urge the fluid composition entering the cyclone inlet downward toward apex 76. 18 An underflow fluid stream is expelled through the lower apex 76. The underflow stream output 19 from the cyclone follows a generally helical descent through the cyclone cavity. The rate of supply of the fluid to be treated to the cyclone 70 causes the fluid to rotate counter-clockwise (in 21 the northern hemisphere) within the cyclone as it progresses from the upper inlet region 74 22 toward the underflow exit of lower apex '76. Variations in density of the constituent components 23 of the fluid composition cause the lighter component materials, primarily the bitumen 24 component, to be directed toward vortex finder 82 in the direction of arrow 86. 21476383.1 14 CA 02787798 2012-08-17 1 As depicted in Figure 3a, when the cyclone is operating properly the fluid exits the apex of they 2 cyclone as a forced spray 89 with a central vapour core 97 =tending along the axis of the 3 cyclone. Near the apex 76 a central zone subtended by the vena cava 91 is formed. The vena 4 cava is the point of reflection or transformation of the descending helix 93 into an ascending helix 95. Contained within this hydraulic structure will be an air core or vapour core 97 6 supported by the helical up and down vortices. This structure is stable above certain operating 7 conditions, below which the flow is said to rope. Under roping conditions the air core and the 8 up-vortex will collapse into a tube of fluid that will exit downward with a twisting motion. 9 Under these circumstances the vortex flow will cut off and there will be zero separation. Roping occurs when the solids content of the undertow slurry becomes intolerably high. 11 The vortex finder 82 has a shortened excursion where the vortex finder lower end 92 extends 12 only a small distance below cyclone inlet 80. A shortened vortex finder allows a portion of the 13 bitumen in the inlet strewn to exit to the overflow output passage 84 without having to make a 14 spiral journey down into the cyclone chamber 98 and back up to exit to the overflow output passage 84. However, some bitumen in the fluid introduced into the cyclone for processing does 16 make this entire journey through the cyclone chamber to exit to the overflow output passage 84. 17 The free vortex height FVH, measured from the lower end of the vortex finder 92 to the 18 undertow outlet 76 of lower apex 88, is long relative to the cyclone diameters DI and DO. 19 Preferably, a mounting plate 94 is provided to mount the cyclone, for example, to a frame structure (not shown). 21 Preferably the lower portion 88 of the cyclone is removably affixed to the body of the cyclone by 22 suitable fasteners 90, such as bolts, to permit the lower portion 88 of the cyclone to be replaced. 23 Fluid velocities obtained in operation of the cyclone, cause mineral materials that are entrained 24 in the fluid directed toward the lower apex undertow outlet 76 to be abrasive. A removable lower apex 88 portion permits a high-wear portion of the cyclone to be replaced as needed for 26 operation of the cyclones. The assembly or packaging of the so-called cyclopac has been 27 designed to facilitate on-line replacement of individual apex units for maintenance and insertion 28 of new abrasion resistant liners. 21476383.1 15 CA 02787798 2012-08-17 1 Figure 3 shows a top view cross-section of the cyclone of Figure 2. The cyclone has an 2 injection path 96 that extends from the input channel 78 to the cyclone inlet 80. Various 3 geometries of injection path can be used, including a path following a straight line or a path 4 following a curved line. A path following a straight line having an opening into the body of the cyclone that is tangential to the cyclone is called a Lupul Ross cyclone. In the preferred 6 embodiment, the injection path 96 follows a curved line that has an involute geometry. An 7 involute injection path assists in directing the fluid supplied to the cyclone to begin to move in a 8 circular direction in preparation for delivery of the fluid through cyclone inlet 80 into the 9 chamber 98 of the cyclone for processing. The counter-clockwise design is for use in the northern hemisphere in order to be in synch with the westerly coriolis force. In the southern 11 hemisphere this direction would be reversed. 12 In the preferred embodiment of the cyclone, the dimensions listed in Table 3 are found: 13 TABLE 3 Path DI DC DO DU FVH ABRV Primary Involute 50131M 200mm 50mm 40mm 1821mm 102mm Cyclone Secondary Involute 50mm 150mm 50mm 50mm 1133mm 105mm Cyclone Lupul Ross Tangent 9.25ram 64mm 19mm 6.4mm 181mm 32nam Cyclone 14 Where: 16 Path is the injection path length geometry. If the path is an involute, the body diameter DC 17 is a parameter of the involute equation that defines the path of entry into the cyclone 18 DI is the inlet diameter at the entry of the fluid flow to the cyclone 19 DC is the body diameter of the cyclone in the region of entry into the cyclone DO is the overflow exit path vortex finder diameter or the outlet pipe diameter 21 DU is the underflow exit path apex diameter at the bottom of the cyclone, also called the 22 vena cava 214763S3.1 16 CA 02787798 2012-08-17 1 FVH is the free vortex height or the distance from the lower end of the vortex finder to the 2 vena cava 3 ABRV is the distance from the centre-line of the inlet flow path to the tip of the vortex 4 Ender. The shorter this distance the more abbreviated is the vortex finder. 6 The cyclones are dimensioned to obtain sufficient vorticity in the down vortex so as to cause a 7 vapor core 97 in the centre of the up-vortex subtended by the vena cava. The effect of this vapor 8 core is to drive the solvent preferentially to the product stream, provided to the overflow output 9 port 84, thereby assuring minimum solvent deportment to tails or under- flow stream, provided to the underflow outlet 76 of lower apex. This is a factor contributing to higher solvent recovery in 11 the process circuit. At nominal solvent ratios the vapor core is typically only millimeters in 12 diameter, but this is sufficient to cause 3% to 4% enrichment in the overhead solvent to bitumen 13 ratio. 14 A workable cyclone for use in processing a diluted bitumen froth composition has a minimum an apex diameter of 40mm to avoid plugging or an intolerably high fluid vorticity. An apex 16 diameter below 40mm would result in high fluid tangential velocity yielding poor life 17 expectancy of the apex due to abrasion even with the most abrasion resistant material. 18 Consequently, a Lupul Ross cyclone design is undesirable because of the small size of openings 19 employed. The embodiments of the primary and secondary cyclones of the dimensions stated in Table 3 21 sustain a small vapour core at flow rates of 180 gallon/min or more. This causes enrichment in 22 the solvent content of the overflow that is beneficial to obtaining a high solvent recovery. The 23 vapour core also balances the pressure drops between the two exit paths of the cyclone. The long 24 body length of these cyclones fosters this air core formation and assists by delivering high gravity forces within the device in a manner not unlike that found in centrifuges, but without the 26 moving parts. In the preferred embodiment of the primary cyclone, the upper inlet region has an 27 inner diameter of 200 mm. The injection path is an involute of a circle, as shown in Figure 3. In. 28 one and one half revolutions prompt bitumen can move into the vortex finder and exit to the 29 overflow output passage 84 if the solvent to bitumen ratio is properly adjusted. The internal dimensions of the secondary cyclones are similar and the same principles apply as were stated in 21476383.1 17 CA 02787798 2012-08-17 1 relation to the primary cyclones. However, the diameter of the body of the secondary cyclone is 2 150 mm to create a higher centrifugal force and a more prominent vapour core. The dimensions 3 of the secondary cyclone are aimed at producing minimum hydrocarbon loss to tails. This is 4 accomplished with as low as 15% hydrocarbon loss, which still allows for a water rejection greater than 50%. 6 The IPS units 12,14 and 22 of the IPS stages are available from manufacturers such as the Model 7 SRC slant rib coalescing oil water separator line of IPS equipment manufactured by Parkson 8 Industrial Equipment Company of Florida, U.S.A.. 9 Figure 4 is a schematic diagram depicting another preferred arrangement of apparatus adapted to carry out the process of the invention. As with Figure 1, the schematic diagram provides an 11 outline of the equipment and the process flows, but does not include details, such as pumps that 12 provide the ability to transport the process fluids from one unit to the next. The apparatus of the 13 invention includes inclined plate separator (LPS) stage units and cyclone stage units and 14 centrifuge stage units, each of which process an input stream to produce an overflow output stream, and an underflow output stream The centrifuge overflow output stream has a bitumen 16 enriched content resulting from a corresponding decrease in solids, fines and water content 17 relative to the bitumen content of the centrifuge input stream. The centrifuge underflow output 18 stream has solids, fines and water with a depleted bitumen content relative to the centrifuge input 19 stream. The centrifuge underflow output stream may be referred to as a bitumen depleted stream. 21 In the general arrangement of the apparatus adapted to carry out the process, inclined plate 22 separator (IPS) units are alternately staged with either cyclone units or centrifuge units such that 23 an IPS stage undefflow feeds a cyclone stage or a centrifuge stage or both a cyclone stage and a 24 centrifuge stage. In addition a cyclone stage overflow or a centrifuge stage overflow is sent to product or feeds an IPS stage. This circuit enables one to take full advantage of centrifuges that 26 might be destined for replacement. In another sense it provides a fallback to the circuit depicted 27 in Figure 1. 28 In Figure 4, the same reference numerals are used to depict like features of the invention. The 29 processing circuit has a circuit inlet 10 to receive a process feed stream 48. The process feed 2147633.1 18 CA 02787798 2012-08-17 = 1 stream is a deaerated bitumen froth output of an oil sands extraction process and is diluted at 11 2 with a suitable solvent, for example naphtha, or a paraffinic or alka.ne hydrocarbon solvent. The 3 diluted bitumen feed stream 50 including a recycle streams 60 and 64 is supplied to a primary 4 IPS stage comprising IPS units 12 and 14 shown as an example of multiple units in a process stage. The overflow output stream 52 of the primary TIPS stage is supplied as a product stream, 6 which is sent to the circuit product outlet line 42 for downstream processing, for example at an 7 upgrader plant. 8 The underflow output stream of the primary US stage is supplied via line 30 as the feed stream 9 68 to a primary hydrocarbon cyclone stage (HCS) comprising for example, a primary cyclone 16. The hydrocarbon cyclone processes a feed stream into a bitumen enriched overflow stream and a 11 bitumen depleted underflow stream. The overflow output stream 56 of the primary cyclone stage 12 on line 18 is directed for further processing depending on the setting of diverter valve 34. 13 Diverter valve 34 is adjustable to direct all or a portion of the primary HCS overflow output 14 stream 56 to a recycle stream 60 that is carried on line 3 to become a recycle input to the feed stream 50 supplied to the primary DPS stage. The portion of the primary HCS overflow output 16 stream that is not directed to recycle stream 60 can become all or a portion of either the 17 secondary IPS feed stream 58 that is delivered to a secondary IPS stage 22 via line 2 or a 18 centrifuge stage feed stream 100 that is delivered to a centrifuge stage 102 via line 1. Naturally 19 diverter valve 34 can be set to divert all of the HCS overflow stream 56 either to the secondary IFS feed stream 58 or to the centrifuge stage 102. 21 When paraffinic solvents are deployed asphaltene production will occur. Under these 22 circumstances the first stage cyclone underflow stream 61 can be configured separate from the 23 second stage cyclones to provide two separate tailings paths for asphaltenes. On the other hand, 24 asphaltene production is very low when naphtha based solvents are deployed in this process and, consequently, two separate tailings paths are not required. 26 Adjustment of diversion 'Valve 34 permits the processing circuit flows to be adjusted to 27 accommodate variations in oil sands ore composition, which is reflected in the composition of 28 the bitumen froth feed stream 48. In this manner, the circuit process feed flow SO to the primary 29 cyclone stage can be set to adapt to the processing requirements providing optimal processing for 23476383.1 19 CA 02787798 2012-08-17 1 the composition of the bitumen froth feed. In some circumstances, such as when the capacity of 2 the secondary TIPS stage 22 and centrifuge stage 102 is exceeded, all or a portion of the primary 3 cyclone stage overflow stream 56 on line 18 is directed to recycle stream 60 by diverter valve 34. 4 The preferred embodiment of a process circuit in accordance with the principles of the invention preferably includes secondary EPS processing equipment or centrifuge processing equipment 6 interconnecting with the primary stage processing equipment by means of diverter valve 34. 7 Where the entire overflow output stream of the primary stage is recycled back to the primary IPS 8 stage, the primary IPS stage process acts as a secondary EPS stage and no stream is supplied to 9 the secondary IPS stage or the centrifuge stage for processing. However, a secondary TIPS stage or centrifuge stage or both is preferably provided to accommodate the variations in composition 11 of the feed froth stream 48 encountered in operation of the process. Secondary TIPS unit 22 12 processes the feed stream 58 received from the overflow of the primary cyclone stage into a 13 bitumen enriched secondary TS overflow output stream on line 32 and a bitumen depleted 14 secondary EPS underflow output stream 59 on line 26. The recovered bitumen of the secondary IPS overflow stream on line 32 is combined with the overflow stream of the primary TS stage to 16 provide the circuit output bitumen product stream 52 delivered to the circuit product outlet line 17 42 for downstream processing and upgrading. The centrifuge stage unit 102 processes the feed 18 stream 100 received from the overflow of the primary cyclone stage into a bitumen enriched 19 centrifuge output stream on line 104 and a bitumen depleted centrifuge underflow output stream 106 on line 108. The recovered bitumen of the centrifuge overflow stream on line 104 is 21 supplied to the circuit output bitumen product stream 52, which is delivered to the circuit product 22 outlet line 42 for downstream processing and upgrading. 23 The secondary stage TS 22 underflow output stream 59 is processed in this embodiment in the 24 same manner as in the embodiment depicted in Figure 1. The secondary HCS underflow output stream and the centrifuge output stream 106 are combined to form stream 66, which is directed 26 to a solvent recovery unit 44. The solvent recovery unit 44 processes stream 66 to produce a 27 circuit tailings stream 54 that is provided to the circuit tails outlet 46 of the circuit. The solvent 28 recovery unit (SRU) 44 is operated to maintain solvent loss to the tailings stream 54 between 29 0.5% to 0.7% of the total solvent fed to the circuit at 11. The tailings stream 54 is sent for disposal on the circuit tails outlet line 46. 21476383.1 20 CA 02787798 2012-08-17 1 The closed loop nature of the recycling of this process reveals two recycling loops. One 2 recycling loop is closed through line 3 from the primary IPS stage and primary HCS. Another 3 recycling loop is closed from line 2 through the secondary [PS stage via line 26 and through the 4 secondary HCS 28 via stream 64, The feed to the disk centrifuges on line 1 does not provide a recycle loop; thus material sent to the disk centrifuge stage is not recycled back to the primary 6 EPS stage. The HCS unit flow rates and pressure drops are maintained at a level that achieves the 7 performance stated in Tables 1 and 2. An input stream of a cyclone is split to the overflow 8 output stream and the underflow output stream and the operating flow rates and pressure drops 9 will determine the split of the input stream to the output streams. Generally, the range of output overflow split will vary between about 50% to about 80% of the input stream by varying the 11 operating flow rates and pressure drops. 12 Although a preferred and other possible embodiments of the invention have been described in 13 detail and shown in the accompanying drawings, it is to be understood that the invention in not 14 limited to these specific embodiments as various changes, modifications and substitutions may be made without departing from the spirit, scope and purpose of the invention as defined in the 16 claims appended hereto. 17 2147633.1 21
