CA3070130C - Process and system for treating bitumen-containing emulsions, such as bitumen froth, integrating naphthenic and paraffinic treatments - Google Patents

Abstract

ABSTRACT A process for treating a bitumen froth or bitumen emulsion derived from an in situ operation including treating the bitumen froth or emulsion with a napthenic diluent and then a paraffinic solvent to recover a deasphalted bitumen product including diluent which can meet pipeline specifications. In some implementations, the process includes in a first stage, mixing a bitumen froth with a naphthenic diluent to form a diluted bitumen froth which is fed to a naphthenic treatment separator to produce a first stage overflow including bitumen and naphthenic diluent and a first stage underflow including bitumen, solids, water and naphthenic diluent; and in a second stage, treating the first stage underflow or a stream derived therefrom with a paraffinic solvent in a paraffinic treatment plant to produce a second stage overflow including an asphaltene-reduced bitumen and paraffinic solvent, and a second stage underflow which includes at least asphaltenes, solids and water. CA 3070130 2020-01-27

Description

PROCESS AND SYSTEM FOR TREATING BITUMEN-CONTAINING
EMULSIONS, SUCH AS BITUMEN FROTH, INTEGRATING
NAPHTHENIC AND PARAFFINIC TREATMENTS
TECHNICAL FIELD
[001] The technical field generally relates to processing bitumen froth or bitumen-containing emulsions recovered from oil sands (e.g., bitumen froth resulting from extraction of surface mined oil sands and/or bitumen-containing emulsions recovered from in situ operations) by integrating naphthenic and paraffinic treatments to produce diluted bitumen products.
BACKGROUND

[002] Bitumen froth produced by extraction of mined oil sands and bitumen-containing emulsions recovered from oil sands in situ operations (e.g., SAGD operations), mainly contains bitumen with a relatively high concentration of solids and water.
Bitumen froth and in situ produced bitumen emulsions requires further treatment before the bitumen can be upgraded to a vendible crude oil.

[003] In situ produced bitumen emulsion is pumped up to the surface and sent to a separation plant where the water is removed from the bitumen. Clean bitumen is then diluted, for instance with a naphthenic diluent or natural gas condensate, before being sent to upgraders or directly sold to the market.

[004] One bitumen froth treatment method involves adding a diluent or solvent to the bitumen froth in order to reduce the viscosity of the bitumen and enable effective gravity separation between the bitumen phase and the water/solids phase. This process is typically referred to as froth treatment. Two types of froth treatment process are currently used in the oil sands: naphthenic froth treatment (NFT) and paraffinic froth treatment (PFT).

[005] In conventional NFT, a naphthenic diluent, also called naphtha, is added to the bitumen froth to form a diluted froth that is subjected to separation to produce diluted bitumen considered to be a relatively clean final product that can be upgraded into crude oil. The diluted bitumen produced from an NFT facility can still contain small amounts of water and fine solids. However, the presence of water and solids in the diluted bitumen can be problematic to the upgrader. Furthermore, the processing of the NFT
underflow, for recovering additional bitumen included therein, can involve high-wear and high-maintenance rotating equipment (e.g., hydrocyclones, centrifuge pumps,). There is therefore an economic impact resulting from sustaining expenses to maintain NFT
operations and upgrading operations for synthetic crude oil production.

[006] PFT uses a lighter diluent than the one used in the NFT, referred to as paraffinic solvent. This solvent is typically used to facilitate the precipitation of some asphaltenes present in the bitumen, the asphaltene precipitates being separated from the bitumen along with water and fine solids in the form of a tailings material, leaving behind a clean bitumen product that can meet pipeline specifications. Common PFTs include countercurrent two-stage processes. The paraffinic solvents can include hydrocarbons in the C3 to C10 range, although alkanes such as pentane or hexane are typically used.
However, PFT can require large amounts of solvents that can be costly and can also lead to relatively high capacity in the tailings solvent recovery units (TSRU), increasing energy requirements and therefore production costs.
SUMMARY

[007] In some implementations, there is provided a process for treating a bitumen froth, comprising:
mixing the bitumen froth with a naphthenic diluent to form a diluted bitumen froth;
in a first stage, treating the diluted bitumen froth in a naphthenic froth treatment separator to produce a first stage overflow including bitumen and naphthenic diluent and a first stage underflow comprising bitumen, solids, water and naphthenic diluent;
in a second stage, treating the first stage underflow or a stream derived from the first stage underflow with a paraffinic solvent in a paraffinic treatment plant to produce a second stage overflow comprising an asphaltene-reduced bitumen and paraffinic solvent, and a second stage underflow which comprises at least asphaltenes, solids and water.

[008] In some implementations, the naphthenic froth treatment separator can comprise at least one gravity settler. In some implementations, the naphthenic froth treatment separator can comprise inclined plate settlers.

[009] In some implementations, the naphtha diluent and the bitumen froth can be mixed at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[0010] In some implementations, the paraffinic treatment plant can comprise paraffinic froth treatment settlers. In some implementations, the paraffinic treatment plant can comprise two paraffinic froth treatment settlers in counter-current configuration.

[0011] In some implementations, the paraffinic solvent can comprise at least one alkane in the C3 to C8 range. In some implementations, the paraffinic solvent can comprise butane, pentane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-pentane, iso-pentane or any mixture thereof.

[0012] In some implementations, the second stage of the process can be performed at a solvent to bitumen ratio (SIB) of from about 0.5 to about 3.

[0013] In some implementations, the paraffinic solvent can comprise butane and the second stage of the process can be performed at a SIB ratio of from about 0.5 to about 1.5.

[0014] In some implementations, the paraffinic solvent can comprise pentane and the second stage can be performed at a SIB ratio of from about 0.8 to about 2.

[0015] In some implementations, the second stage of the process can be performed at a temperature of from about 50 C to about 100 C. In some implementations, the second stage can be performed at a temperature of from about 60 C to about 90 C. In some implementations, the second stage can be performed at a temperature of from about 70 C
to about 90 C.

[0016] In some implementations, the paraffinic solvent can comprise butane and the second stage can be performed at a temperature of from about 50 C to about 90 C. In some implementations, the paraffinic solvent can comprise butane and the second stage can be performed at a temperature of from about 50 C to about 80 C.

[0017] In some implementations, the second stage of the process can be performed at a pressure of from about 40 psi to about 300 psi. In some implementations, the second stage can be performed at a pressure of from about 40 psi to about 200 psi.

[0018] In some implementations, the paraffinic solvent can comprise butane and the second stage of the process can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[0019] In some implementations, the first stage underflow can comprise from about 5%
to about 30% bitumen. In some implementations, the first stage underflow can comprise from about 35% to about 60% bitumen.

[0020] In some implementations, the process can further comprise adding bitumen froth to the first stage underflow to obtain the stream derived from the first stage underflow.

[0021] In some implementations, the process can further comprise removing at least a portion of the solids and/or water from the first stage underflow to obtain the stream derived from the first stage underflow.

[0022] In some implementations, the process can further comprise removing at least a portion of the solids and/or water from the first stage underflow to obtain a pre-treated first stage underflow and adding bitumen froth to the pre-treated first stage underflow to obtain the stream derived from the first stage underflow.

[0023] In some implementations, the bitumen froth that is added to the first stage underflow can be derived from the bitumen froth used in the first stage.

[0024] In some implementations, the step of removing at least a portion of the solids and/or water from the first stage underflow can be performed using hydrocyclones. In some implementations, the step of removing at least a portion of the solids and/or water from the first stage underflow can be performed using a single stage of hydrocyclones.

[0025] In some implementations, the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow can be less than about 15%. In some implementations, the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow can be from about 1% to about 14% 05-asphaltenes.

[0026] In some implementations, the paraffinic solvent can comprise butane or pentane and the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow is from about 7% to about 12% C5-asphaltenes.

[0027] In some implementations, the process can further further comprise removing the paraffinic solvent from the second stage overflow in a solvent recovery unit to produce a deasphalted bitumen stream.

[0028] In some implementations, the process can further comprise recycling the paraffinic solvent to the second stage treatment.

[0029] In some implementations, the paraffinic treatment plant can comprise a first stage settler and a second stage settler in counter-current configuration and the process can further comprise recycling the paraffinic solvent to the second stage settler of the paraffinic treatment plant.

[0030] In some implementations, the process can further comprise adding naphthenic diluent to the deasphalted bitumen stream.

[0031] In some implementations, the deasphalted bitumen stream can have a base sediment and water (BS&W) of about 0.1 % or lower.

[0032] In some implementations, the process can further comprise mixing the deasphalted bitumen stream with the first stage overflow to obtain a diluted bitumen product.

[0033] In some implementations, the process can further comprise mixing the deasphalted bitumen stream with the first stage overflow to obtain a diluted bitumen product having a BS&W that is lower than a BS&W of the first stage overflow.

[0034] In some implementations, the process can further comprise mixing the deasphalted bitumen stream with the first stage overflow to obtain a diluted bitumen product having a BS&W of about 1.5 % or lower. In some implementations, the process can further comprise mixing the deasphalted bitumen stream with the first stage overflow to obtain a diluted bitumen product having a BS&W of about 1 % or lower.

[0035] In some implementations, the deasphalted bitumen stream can represent about 30% to about 70% of the diluted bitumen product.

[0036] In some implementations, the first stage overflow can represent about 35% to about 65% of the diluted bitumen product.

[0037] In some implementations, there is provided a system for treating a bitumen froth, corn prisi ng :
a first bitumen froth line for providing a first bitumen froth stream;
a first naphthenic diluent line for adding a first naphthenic diluent stream into the first bitumen froth stream to produce a diluted bitumen froth;
a first stage separation apparatus for separating the diluted bitumen froth into a first stage overflow comprising bitumen and naphthenic diluent and a first stage underflow comprising bitumen, solids, water and naphthenic diluent;
a paraffinic solvent line for adding a paraffinic solvent-containing stream to the first stage underflow or a stream derived from the first stage underflow and producing a second stage feed stream comprising bitumen, paraffinic solvent, solids and water;
a second stage separation apparatus for separating the second stage feed stream into a second stage overflow comprising an asphaltene-reduced bitumen and paraffinic solvent, and a second stage underflow comprising asphaltenes, solids and water.

[0038] In some implementations, the first stage separation apparatus can comprise at least one gravity settlers. In some implementations, the first stage separation apparatus can comprise inclined plate settlers.

[0039] In some implementations, the first naphthenic diluent stream can be added into the first bitumen froth stream at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[0040] In some implementations, the second stage separation apparatus can comprise paraffinic froth treatment settlers. In some implementations, the second stage separation apparatus can comprise two paraffinic froth treatment settlers in counter-current configuration.

[0041] In some implementations, the paraffinic solvent can comprise at least one alkane in the C3 to C8 range. In some implementations, the paraffinic solvent can comprise butane, pentane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-pentane, iso-pentane or any mixture thereof.

[0042] In some implementations, the second stage feed stream can have a solvent to bitumen (SIB) ratio of from about 0.5 to about 3.

[0043] In some implementations, the paraffinic solvent can comprise butane and the second stage feed stream can have a SIB ratio of from about 0.5 to about 1.5.

[0044] In some implementations, the paraffinic solvent can comprise pentane and the second stage feed stream can have a SIB ratio of from about 0.8 to about 2.

[0045] In some implementations, the separation in the second stage separation apparatus can be performed at a temperature of from about 50 C to about 100 C. In some implementations, the separation in the second stage separation apparatus can be performed at a temperature of from about 60 C to about 90 C. In some implementations, the separation in the second stage separation apparatus can be performed at a temperature of from about 70 C to about 90 C.

[0046] In some implementations, the paraffinic solvent can comprise butane and the separation in the second stage separation apparatus can be performed at a temperature of from about 50 C to about 90 C.

[0047] In some implementations, the paraffinic solvent can comprise butane and the separation in the second stage separation apparatus can be performed at a temperature of from about 50 C to about 80 C.

[0048] In some implementations, the separation in the second stage separation apparatus can be performed at a pressure of from about 40 psi to about 300 psi. In some implementations, the separation in the second stage separation apparatus can be performed at a pressure of from about 40 psi to about 200 psi.

[0049] In some implementations, the paraffinic solvent can comprise butane and the separation in the second stage separation apparatus can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[0050] In some implementations, the first stage underflow can comprise from about 5%
to about 30% bitumen. In some implementations, the first stage underflow can comprise from about 35% to about 60% bitumen.

[0051] In some implementations, the system can further comprise a second bitumen froth line for adding a second bitumen froth stream to the first stage underflow and producing the stream derived from the first stage underflow.

[0052] In some implementations, the system can further comprise equipment upstream the second stage separation apparatus for removing at least a portion of the solids and/or water from the first stage underflow and producing the stream derived from the first stage underflow.

[0053] In some implementations, the system can further comprise:
equipment upstream the second stage separation apparatus for removing at least a portion of the solids and/or water from the first stage underflow and obtaining a pre-treated first stage underflow; and a second bitumen froth line for adding a second bitumen froth stream to the pre-treated first stage underflow and producing the stream derived from the first stage underflow.

[0054] In some implementations, the second bitumen froth line can be derived from the first bitumen froth line.

[0055] In some implementations, the equipment for removing at least a portion of the solids and/or water can comprise hydrocylcones. In some implementations, the equipment for removing at least a portion of the solids and/or water can comprise a single stage of hydrocylcones.

[0056] In some implementations, the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow can be less than about 15%. In some implementations, the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow can be from about 1% to about 14% C5-asphaltenes.

[0057] In some implementations, the paraffinic solvent can comprise butane or pentane and the asphaltene content in the asphaltene-reduced bitumen of the second stage overflow can be from about 7% to about 12% C5-asphaltenes.

[0058] In some implementations, the system can further comprise a solvent recovery unit for separating the second stage overflow into a paraffinic solvent stream and a deasphalted bitumen stream.

[0059] In some implementations, the system can further comprise a recycling line for returning at least a portion of the paraffinic solvent stream to the second stage separation apparatus.

[0060] In some implementations, the second stage separation apparatus can comprise a first stage settler and a second stage settler in counter-current configuration and the system can further comprise a recycling line for returning at least a portion of the paraffinic solvent stream to the second stage settler of the second stage separation apparatus.

[0061] In some implementations, the system can further comprise a second naphthenic diluent line for adding a second naphthenic diluent stream to the deasphalted bitumen stream. In some implementations, the second naphthenic diluent line can be derived from the first naphthenic diluent line.

[0062] In some implementations, the deasphalted bitumen stream can have a base sediment and water (BS&W) of about 0.1 % or lower.

[0063] In some implementations, the system can further comprise a mixer for mixing the deasphalted bitumen stream and the first stage overflow and producing a diluted bitumen product.

[0064] In some implementations, the diluted bitumen product can have a BS&W
that is lower than a BS&W of the first stage overflow.

[0065] In some implementations, the diluted bitumen product can have a BS&W of about 1.5 % or lower. In some implementations, the diluted bitumen product can have a BS&W
of about 1 % or lower.

[0066] In some implementations, the deasphalted bitumen stream can represent about 30% to about 70% of the diluted bitumen product.

[0067] In some implementations, the first stage overflow can represent about 35% to about 65% of the diluted bitumen product.

[0068] In some implementations, there is provided a process for treating a bitumen froth, comprising:
mixing the bitumen froth with a naphtha diluent to form a naphtha diluted bitumen froth;
adding a paraffinic solvent comprising butane, pentane or a mixture thereof to the naphtha diluted bitumen froth or a stream derived from the naphtha diluted bitumen froth, to form a combined stream; and separating the combined stream in a paraffinic treatment plant (PTP) into a PTP
overflow comprising an asphaltene-reduced bitumen, paraffinic solvent and naphtha, and a PTP underflow comprising at least asphaltenes, solids and water.

[0069] In some implementations, the paraffinic treatment plant can comprise paraffinic froth treatment settlers. In some implementations, the paraffinic treatment plant can comprise two paraffinic froth treatment settlers in counter-current configuration.

[0070] In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof. In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.

[0071] In some implementations, the process can further comprise separating the naphtha diluted bitumen froth in a naphthenic treatment plant (NIP) to recover the stream derived from the naphtha diluted bitumen froth as an NTP underflow, and wherein the paraffinic solvent is added to the NIP underflow to form the combined stream.
In some implementations, the NIP can comprise at least one gravity settler. In some implementations, the at least one gravity settler can comprise inclined plate settlers.

[0072] In some implementations, the naphtha diluent can be added to the bitumen froth at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[0073] In some implementations, the paraffinic solvent can be added to the naphtha diluted bitumen froth or the stream derived therefrom at a solvent to bitumen ratio (SIB) of from about 0.5 to about 2.5.

[0074] In some implementations, the paraffinic solvent can comprise butane and the paraffinic solvent can be added to the naphtha diluted bitumen froth or the stream derived therefrom at a solvent to bitumen (S/B) ratio of from about 0.5 to about 1.5.

[0075] In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 90 C. In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 80 C.

[0076] In some implementations, the separation in the PTP can be performed at a pressure of from about 50 psi to about 200 psi.

[0077] In some implementations, the paraffinic solvent can comprise butane and the separation in the PTP can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[0078] In some implementations, the asphaltene content in the asphaltene-reduced bitumen can be from about 7% to about 12% C5-asphaltenes.

[0079] In some implementations, the process can further comprise removing the paraffinic solvent from the PTP overflow in a solvent recovery unit to produce a naphtha diluted deasphalted bitumen stream.

[0080] In some implementations, the naphtha diluted deasphalted bitumen stream can have a base sediment and water (BS&VV) of about 0.1 % or lower.

[0081] In some implementations, there is provided a system for treating a bitumen froth, comprising:
a bitumen froth line for providing a bitumen froth stream;
a naphtha diluent line for adding a naphtha diluent stream into the bitumen froth stream to produce a naphtha diluted bitumen froth;
a paraffinic solvent line for adding a paraffinic solvent-containing stream to the naphtha diluted bitumen froth or a stream derived from the naphtha diluted bitumen froth and producing a combined stream, wherein the paraffinic solvent comprises butane, pentane or a mixture thereof;
a paraffinic treatment plant (PTP) for separating the combined stream into a PTP
overflow comprising an asphaltene-reduced bitumen, the paraffinic solvent and naphtha and a PTP underflow comprising at least asphaltenes, solids and water.

[0082] In some implementations, the paraffinic treatment plant can comprise a paraffinic froth treatment plant. In some implementations, the paraffinic treatment plant can comprise paraffinic froth treatment settlers. In some implementations, the paraffinic treatment plant can comprise two paraffinic froth treatment settlers in counter-current configuration.

[0083] In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.

[0084] In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.

[0085] In some implementations, the system can further comprise a naphthenic treatment plant (NTP) for receiving the naphtha diluted bitumen froth and recovering the stream derived from the naphtha diluted bitumen froth as an NTP underflow, and the paraffinic solvent-containing stream can be added to the NTP underflow to form the combined stream. In some implementations, the NTP can comprise at least one gravity settler. In some implementations, the at least one gravity settler can comprise inclined plate settlers.

[0086] In some implementations, the naphtha diluent stream can be added to the bitumen froth stream at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[0087] In some implementations, the paraffinic solvent can be added to the naphtha diluted bitumen froth or the stream derived therefrom at a solvent to bitumen ratio (S/B) of from about 0.5 to about 2.5.

[0088] In some implementations, the paraffinic solvent can comprise butane and the paraffinic solvent is added to the naphtha diluted bitumen froth or the stream derived therefrom at a solvent to bitumen (S/B) ratio of from about 0.5 to about 1.5.

[0089] In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 90 C. In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 80 C.

[0090] In some implementations, the separation in the PTP can be performed at a pressure of from about 50 psi to about 200 psi.

[0091] In some implementations, the paraffinic solvent can comprise butane and the separation in the PTP can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[0092] In some implementations, the asphaltene content in the asphaltene-reduced bitumen can be from about 7% to about 12% C5-asphaltenes.

[0093] In some implementations, the system can further comprise a solvent recovery unit for separating the PTP overflow into a paraffinic solvent stream and a naphtha diluted deasphalted bitumen stream.

[0094] In some implementations, the naphtha diluted deasphalted bitumen stream can have a base sediment and water (BS&W) of about 0.1 % or lower.

[0095] In some implementations, there is provided a process for treating a bitumen-containing stream comprising a bitumen emulsion produced from an in situ operation, wherein the process comprises:
treating the bitumen-containing stream with a naphtha diluent to obtain a naphtha diluted bitumen-containing stream;
adding a paraffinic solvent to the naphtha diluted bitumen-containing stream to form a combined stream; and separating the combined stream in a paraffinic treatment plant (PTP) into a PTP
overflow comprising an asphaltene-reduced bitumen, paraffinic solvent and naphtha, and a PTP underflow comprising at least asphaltenes, solids and water.

[0096] In some implementations, the paraffinic treatment plant can comprise paraffinic froth treatment settlers. In some implementations, the paraffinic treatment plant can comprise two paraffinic froth treatment settlers in counter-current configuration.

[0097] In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.

[0098] In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.

[0099] In some implementations, the bitumen-containing stream can comprise a mixture of the bitumen emulsion produced from an in situ operation with a bitumen froth.

[00100] In some implementations, the step of treating the bitumen-containing stream with the naphtha diluent can be performed at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[00101] In some implementations, the paraffinic solvent can be added to the naphtha diluted bitumen-containing stream at a solvent to bitumen ratio (SIB) of from about 0.5 to about 2.5.

[00102] In some implementations, the paraffinic solvent can comprise butane and the paraffinic solvent can be added to the naphtha diluted bitumen-containing stream at a solvent to bitumen (S/B) ratio of from about 0.5 to about 1.5.

[00103] In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 90 C. In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 80 C.

[00104] In some implementations, the separation in the PTP can be performed at a pressure of from about 50 psi to about 200 psi.

[00105] In some implementations, the paraffinic solvent can comprise butane and the separation in the PTP can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[00106] In some implementations, the asphaltene content in the asphaltene-reduced bitumen can be from about 7% to about 12% C5-asphaltenes.

[00107] In some implementations, the process can further comprise removing the paraffinic solvent from the PTP overflow in a solvent recovery unit to produce a naphtha diluted deasphalted bitumen stream.

[00108] In some implementations, the naphtha diluted deasphalted bitumen stream can have a base sediment and water (BS&W) of about 0.1 % or lower.

[00109] In some implementations, the step of treating the bitumen-containing stream with the naphtha diluent can be performed in at least one gravity settler, the naphtha diluted bitumen-containing stream being produced as a gravity settler underflow. In some implementations, the at least one gravity settler comprises inclined plate settlers.

[00110] In some implementations, the in situ operation can be a steam assisted gravity drainage (SAGD) operation, a solvent assisted in situ operation or a combination thereof.

[00111] In some implementations, the in situ operation can be a steam assisted gravity drainage (SAGD) operation.

[00112] In some implementations, there is provided a system for treating a bitumen-containing stream comprising a bitumen emulsion produced from an in situ operation, wherein the system comprises:
a line for providing the bitumen-containing stream;
a naphtha diluent line for adding a naphtha diluent stream into the bitumen-containing stream to produce a naphtha diluted bitumen-containing stream;
a paraffinic solvent line for adding a paraffinic solvent-containing stream to the naphtha diluted bitumen-containing stream or a stream derived therefrom comprising bitumen, solids, water and naphtha diluent to produce a combined stream;
a paraffinic treatment plant (PTP) for separating the combined stream into a PTP
overflow comprising an asphaltene-reduced bitumen, the paraffinic solvent and naphtha and a PTP underflow comprising at least asphaltenes, solids and water.

[00113] In some implementations, the paraffinic treatment plant can comprise a paraffinic froth treatment plant. In some implementations, the paraffinic treatment plant can comprise paraffinic froth treatment settlers. In some implementations, the paraffinic treatment plant can comprise two paraffinic froth treatment settlers in counter-current configuration.

[00114] In some implementations, the paraffinic solvent comprises n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.

[00115] In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.

[00116] In some implementations, the bitumen-containing stream can comprise a mixture of the bitumen emulsion produced from an in situ operation with a bitumen froth.

[00117] In some implementations, the naphtha diluent stream can be added to the bitumen-containing stream at a naphtha diluent to bitumen (D/B) ratio of from about 0.1 to about 0.4.

[00118] In some implementations, the paraffinic solvent can be added to the naphtha diluted bitumen-containing stream at a solvent to bitumen ratio (SIB) of from about 0.5 to about 2.5.

[00119] In some implementations, the paraffinic solvent can comprise butane and the paraffinic solvent can be added to the naphtha diluted bitumen-containing stream at a solvent to bitumen (S/B) ratio of from about 0.5 to about 1.5.

[00120] In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 90 C. In some implementations, the separation in the PTP can be performed at a temperature of from about 50 C to about 80 C.

[00121] In some implementations, the separation in the PTP can be performed at a pressure of from about 50 psi to about 200 psi.

[00122] In some implementations, the paraffinic solvent can comprise butane and the separation in the PTP can be performed at a pressure of from about 100 psi to about 200 psi and at a temperature of from about 50 C to about 80 C.

[00123] In some implementations, the asphaltene content in the asphaltene-reduced bitumen can be from about 7% to about 12% C5-asphaltenes.

[00124] In some implementations, the system can further comprise a solvent recovery unit for separating the PTP overflow into a paraffinic solvent stream and a naphtha diluted deasphalted bitumen stream.

[00125] In some implementations, the naphtha diluted deasphalted bitumen stream can have a base sediment and water (BS&VV) of about 0.1 % or lower.

[00126] In some implementations, the system can further comprise at least one gravity settler to receive the naphtha diluted bitumen-containing stream and recover the stream derived therefrom comprising bitumen, solids, water and naphtha diluent as a gravity settler underflow. In some implementations, the at least one gravity settler can comprise inclined plate settlers.

[00127] In some implementations, the in situ operation can be a steam assisted gravity drainage (SAGD) operation, a solvent assisted in situ operation or a combination thereof.

[00128] In some implementations, the in situ operation can be a steam assisted gravity drainage (SAGD) operation.
[0128a] In some implementations, there is provided a process for reducing a base sediment and water (BS&VV) of a diluted bitumen stream recovered as an overflow of a naphthenic froth treatment, comprising blending the diluted bitumen stream with a deasphalted bitumen stream recovered from a paraffinic froth treatment to produce a diluted bitumen product.
[0128b] In some implementations, the diluted bitumen stream can be recovered as an overflow of a naphthenic froth treatment gravity settler.
[0128c] In some implementations, the deasphalted bitumen stream can be recovered from a solvent recovery unit of the paraffinic froth treatment.
[0128d] In some implementations, the process can further comprise adding naphthenic diluent to the deasphalted bitumen stream before blending with the diluted bitumen stream.
[0128e] In some implementations, the deasphalted bitumen stream can have a BS&W of about 0.1 % or lower.
Date Recue/Date Received 2021-07-23 17a [0128f] In some implementations, the diluted bitumen product resulting from the blending can have a BS&W of about 1.5 % or lower.
[0128g] In some implementations, the diluted bitumen product resulting from the blending can have a BS&W of about 1 % or lower.
[0128h] In some implementations, the deasphalted bitumen stream can represent about 30% to about 70% of the diluted bitumen product.
[0128i] In some implementations, the diluted bitumen stream can represent about 35% to about 65% of the diluted bitumen product.
[0128j] In some implementations, the paraffinic froth treatment can employ at least one alkane in the 03 to 08 range as paraffinic solvent.
[0128k] In some implementations, the paraffinic solvent can comprise butane, pentane or any mixture thereof.
[01281] In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.
[0128m] In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.
[0128n] In some implementations, there is provided a process for reducing an asphaltene content of a diluted bitumen stream recovered as an overflow of a naphthenic froth treatment, comprising blending the diluted bitumen stream with a deasphalted bitumen stream recovered from a paraffinic froth treatment to produce a diluted bitumen product.
[01280] In some implementations, the diluted bitumen stream can be recovered as an overflow of a naphthenic froth treatment gravity settler.
[0128p] In some implementations, the deasphalted bitumen stream can be recovered from a solvent recovery unit of the paraffinic froth treatment.
[0128q] In some implementations, the process can further comprise adding naphthenic diluent to the deasphalted bitumen stream before blending with the diluted bitumen stream.
Date Recue/Date Received 2021-07-23 17b [0128r] In some implementations, the deasphalted bitumen stream can represent about 30% to about 70% of the diluted bitumen product.
[0128s] In some implementations, the diluted bitumen stream can represent about 35% to about 65% of the diluted bitumen product.
[0128t] In some implementations, the paraffinic froth treatment can employ at least one alkane in the 03 to 08 range as paraffinic solvent.
[0128u] In some implementations, the paraffinic solvent can comprise butane, pentane or any mixture thereof.
[0128v] In some implementations, the paraffinic solvent can comprise n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.
[0128w] In some implementations, the paraffinic solvent can comprise n-butane, iso-butane or any mixture thereof.
BRIEF DESCRIPTION OF DRAWINGS

[00129] Fig. 1 is a flow diagram of a bitumen froth treatment process according to one implementation, including a naphthenic diluent treatment stage followed by a paraffinic solvent treatment stage.

[00130] Fig. 2 is a flow diagram of a bitumen froth treatment process according to another implementation, including a naphthenic diluent treatment stage followed by a paraffinic solvent treatment stage, and further operation features such as combining the deasphalted bitumen product resulting from the paraffinic treatment with the diluted bitumen overflow product from the naphthenic treatment.

[00131] Fig. 3 is a flow diagram of a bitumen froth treatment process according to the implementation presented in Fig. 2, including a further operation feature involving addition of fresh bitumen froth to the underflow of the naphthenic treatment stage before the paraffinic solvent treatment stage.
Date Recue/Date Received 2021-07-23

[00132] Fig. 4 is a flow diagram of a bitumen froth treatment process according to a further implementation, including a naphthenic diluent treatment stage followed by a paraffinic solvent treatment stage, and further operation features such as subjecting the underflow of the naphthenic treatment stage to a hydrocyclone pre-treatment before the paraffinic solvent treatment stage.

[00133] Fig. 5 is a flow diagram of a bitumen froth treatment process according to the implementation presented in Fig. 4, including a further operation feature involving adding fresh bitumen froth to the pre-treated stream before the paraffinic solvent treatment stage.

[00134] Fig. 6 is a flow diagram of a bitumen froth treatment process according to another implementation, including a naphthenic diluent addition step followed by a paraffinic solvent treatment stage.

[00135] Fig. 7 is a flow diagram of an in-situ recovered bitumen emulsion treatment process according to another implementation, including a naphthenic diluent addition step followed by a paraffinic solvent treatment stage.

[00136] Fig. 8 is a flow diagram representing a process according to another implementation involving the treatment of an emulsion including a mixture of an in-situ recovered bitumen-containing and bitumen froth, the process including a naphthenic diluent addition step followed by a paraffinic solvent treatment stage.
DETAILED DESCRIPTION

[00137] The technology described herein concerns processes and systems for treating bitumen froth and/or bitumen emulsions derived from in situ operations, generally involving a naphthenic diluent treatment followed by a paraffinic solvent treatment.

[00138] In the present description, the terms "a", "an", and "one" can be defined to mean "at least one", that is, these terms do not exclude a plural number of elements, unless stated otherwise.

[00139] The term "about" that modifies a value, condition, or characteristic of a feature of an exemplary embodiment, should be understood to mean that the value, condition, or characteristic is defined within tolerances that are acceptable for the proper operation of this exemplary embodiment for its intended application or that fall within an acceptable range of experimental error. In particular, the term "about" generally refers to a range of numbers that one skilled in the art would consider equivalent to the stated value (e.g., having the same or equivalent function or result). In some instances, the term "about"
means a variation of 10 percent of the stated value.

[00140] The various values mentioned in the present description, including stream or product ratios and/or percentages are expressed in weight, unless mentioned otherwise.

[00141] In some implementations, the process can involve treating a bitumen froth or a stream derived therefrom with a naphthenic diluent followed by a paraffinic solvent treatment. The bitumen froth can be derived from an oil sands surface mining operation.

[00142] In the various implementations, the bitumen froth can be a froth obtained in the primary extraction of mined oils sands. Extraction can involve the removal and separation of bitumen from sand using water-based gravity separation. For instance, mined oil sands can be crushed and sized and mixed with process water to form a slurry that is hydrotransported to form a conditioned slurry. The conditioned slurry can be fed into a primary separation vessel (PSV) operated to produce a solids-rich aqueous underflow, a middlings stream including fine solids, water and residual bitumen, and an overflow bitumen froth stream. The middlings stream can be subjected to secondary and tertiary separation in additional separator vessels that, in turn, produce overflow froth streams with enriched bitumen content. Such froth stream can be recycled back into the PSV or added to the main bitumen froth stream. Primary extraction thus includes various separator vessels that generate bitumen-containing froth material that requires further treatment to remove water and solids.

[00143] The bitumen froth can contain about 50-60% bitumen, as well as water and fine solids. A typical froth can contain about 10 to 14% fine solids. However, some bitumen froth can have lower or higher solids contents. The water content of the bitumen froth can be up to about 30%, or sometimes even up to about 40% water, although bitumen froths with water content of 30% or less are considered of better quality. The bitumen froth resulting from primary extraction is usually highly aerated and can undergo a deaeration step before being pumped to a froth storage tank and/or before being further treated to recover a cleaner bitumen product. The expression "bitumen froth" as used in the present description not only refers to the bitumen froth recovered from a primary separation vessel (PSV), but can also refer to other bitumen-enriched streams from the oil sands primary =
extraction process. It also includes bitumen froth streams that could be derived from tailings, e.g., where the tailings have been subjected to a separation process to recover residual bitumen in the form of a froth. In addition, the bitumen froth can be a mixture of bitumen froth streams derived from different PSVs and/or other separation vessels.

[00144] In some implementations, the process can involve subjecting the underflow of a naphthenic froth treatment to a paraffinic solvent treatment to produce a deasphalted bitumen-containing stream, which, in some implementations, can be subjected to further treatments as will be explained below. In some implementations, the underflow of the naphthenic froth treatment can be pre-treated before the paraffinic solvent treatment. In other implementations, the process can involve a step of adding a naphthenic diluent to a bitumen froth stream to form a naphtha diluted bitumen froth that can be directly subjected to a paraffinic solvent treatment to produce a deasphalted bitumen-containing product.

[00145] Naphthenic diluent generally includes a mixture of aliphatic, naphthenic and aromatic hydrocarbons and can contain a wide range of hydrocarbons in the C5 to C10 range. Naphthenic diluent, often referred to as "naphtha", can be sourced from an upgrader or various types of refining units. In some implementations, the naphthenic diluent can have a low concentration of aromatics (e.g., up to about 10 wt%
aromatics).
However, the concentration of aromatics in the naphthenic diluent can vary depending on its source. Low-aromatic diluents can have certain advantages in the processes described herein, as will be explained further below.

[00146] The paraffinic solvent can include hydrocarbons in the C3 to C8 range.
The paraffinic solvent used in the present process can be qualified as a deasphalting solvent.
In some implementations, the paraffinic solvent can include at least one alkane in the C3 to C8 range, such as at least one normal or iso-alkane in the C3 to C8 range.
The paraffinic solvent can also include any mixture of such normal and/or iso-alkanes.
Examples of paraffinic solvent can include butane or pentane or a mixture thereof. For instance, the paraffinic solvent can include n-butane, isobutane, n-pentane or isopentane or any mixture thereof. In some implementations, the paraffinic solvent can include n-pentane, iso-pentane or a mixture thereof. In other implementations, the solvent can include n-butane, iso-butane or a mixture thereof. In the following description, the term "butane" can thus encompass n-butane, iso-butane or a mixture thereof and the term "pentane" can encompass n-pentane, iso-pentane or a mixture thereof. Although the paraffinic solvent mainly contains normal and/or iso-alkanes, other isomers can still be present, at least traces thereof, in the solvent. The paraffinic solvent can be derived from the upgrading facility used to process bitumen.

[00147] Various implementations of the process will now be described in greater detail and referring to the figures.

[00148] Fig. 1 represents a two-stage process involving the treatment of a bitumen froth, such as bitumen froth from primary extraction, to recover at least one diluted bitumen product, which can, in turn, be sent to an upgrader (not shown in the figures) to produce a transportable and sellable synthetic crude oil. In a first stage of the process, bitumen froth 10 is mixed with a naphtha diluent 12 to form a diluted bitumen froth and the diluted bitumen froth is then sent to an NFT plant 14 for separating a diluted bitumen phase from a solids/water phase. In some implementations, the NFT plant 14 includes one or more inclined plate separators (IPS), also commonly referred to as inclined plate settlers, to enhance the separation between the aqueous and bitumen phases. The separation is preferably performed by gravity. In some implementations, the NFT plant 14 is operated at higher pressure than the vapor pressure of the diluent under the safety limits. For instance, the NFT can be operated at pressures ranging from about 2 to 10 psig and at temperatures of from about 70 C to about 90 C. The diluent to bitumen ratio (D/B ratio) can vary but is typically from about 0.3 to about 0.7. However, the D/B ratio can be less than 0.3 in some implementations. Two different streams are recovered from the NFT
plant 14: an overflow stream 16 containing bitumen and naphthenic solvent and an underflow stream 18 containing at least some solids and water. The stream recovered as the NFT overflow 16, which mainly contains naphtha diluted bitumen, can also include some residual water and solids. The residual water can further include dissolved salts and chlorides. The NFT underflow 18 includes solids and water, and a non-negligible amount of bitumen and naphthenic diluent. Since asphaltene components of bitumen are soluble in the naphthenic diluent, both the NFT overflow 16 and underflow 18 thus include full asphaltene components.

[00149] In some implementations, the separation in the NFT stage can be performed to generate an NFT underflow 18 including a fairly large amount of bitumen, for instance up to about 60% bitumen, which is notably higher than typical NFT processes. In other implementations, the bitumen content of the NFT underflow 18 can be up to 40%
bitumen.

The bitumen content of the NFT underflow 18 can be between 35% and 60%
bitumen, between 40% and 55% bitumen, or between 45% and 50% bitumen. Still, in some implementations, the bitumen content of the NFT underflow can range from about 5% to about 30%. Hence, the NFT plant 14 can be operated under conditions where more bitumen is present in the NFT underflow than in a conventional NET operation.
Operating the NFT gravity separation apparatus (e.g., one or more IPS's) in different underflow-to-feed split conditions (e.g., 0.4 to 0.6) can be used so that the NET underflow has a higher content of bitumen than usual, and can also result in a diluted bitumen NFT
overflow of better quality, such as with lower solids and water content.

[00150] In some implementations, the NET overflow 16 can include from about 2%
to about 2.5% base sediment and water (BS&W). In further implementations, the NET

overflow 16 can include from about 1.5% to about 2.0% water and from about 0.5% to about 1.0% solids. In some implementations, the NFT plant can be operated such that the NFT overflow includes from about 1.5% to about 1.7% water and from about 0.5%
to about 0.7% solids.

[00151] The second stage of the process includes a paraffinic solvent treatment performed in a paraffinic treatment plant 24. In some implementations, the paraffinic treatment plant 24 can include PET-type settlers, which can be gravity settlers with cylindrical walls and conical bottom sections. A paraffinic solvent 20, such as a C3-C8 alkane, is pumped from a solvent tank 22 and then mixed with the NFT underflow 18, or a stream derived from the NET underflow 18 as will be further detailed below.
The resulting mixed stream, which can be referred to as a second stage feed stream or a solvent diluted feed stream, is then sent to the paraffinic treatment plant 24 where at least the solids and water carried with the NFT underflow stream 18 can be separated from the mixed stream.
Upon treatment with the paraffinic solvent, some asphaltenes in the bitumen in the NET
underflow are precipitated out from the liquid phase of the mixed stream. In the settlers, the asphaltene precipitates as well as water and solids are separated from the bitumen phase and are withdrawn as a paraffinic treatment underflow 28. It is worth noting that the paraffinic treatment underflow 28 can include some bitumen, residual naphthenic diluent and paraffinic solvent in addition to asphaltenes, solids and water. The paraffinic treatment overflow stream 26, which can be qualified as an asphaltene-reduced bitumen-rich stream, includes predominantly bitumen, paraffinic solvent and some naphtha with very low water and solids content.

[00152] The paraffinic treatment settlers can be arranged counter-currently so that a first settler receives the feed and produces an overflow and an underflow, paraffinic solvent is added to the first stage underflow, the second settler receives the solvent diluted first stage underflow as the second stage feed, the second settler produces an overflow and an underflow, and the second stage overflow is recycled back into the first stage feed to provide the source of paraffinic solvent to the first stage. A three-stage counter-current configuration is also possible. In two-stage counter-current configuration, the first stage overflow is the paraffinic treatment overflow stream 26, and the second stage underflow is the paraffinic treatment underflow 28. It should be noted, however, that various other configurations are possible for the configuration of the paraffinic treatment plant 24. For instance, the pure solvent can be added to the first stage feed and/or to the second stage feed; the settler design can be such that only one large settler is used; and so on.

[00153] The paraffinic solvent used in the paraffinic treatment stage of the process can be selected depending on its asphaltene precipitation capability considering that lighter alkanes tend to enhance precipitation compared to heavier alkanes. Hence, a C4 or C5-alkane can be used to precipitate more asphaltenes at relative solvent to bitumen (SIB) ratios versus a heavier solvent, such as C7-alkane. In some implementations, the make-up paraffinic solvent used in the process can be recycled from a downstream upgrading operation, which can be a proximate bitumen upgrading operation that is part of an overall integrated facility. For instance, the paraffinic solvent can be a product of an upgrading operation that receives the bitumen product produced by the two-stage process described herein. Hence, in some implementations, the present process can benefit from integration of downstream operations, which in turn can reduce costs and the environmental impact of the overall process.

[00154] In some implementations, the second stage paraffinic treatment (PT) can be performed at temperatures ranging from about 50 C to about 100 C. In some implementations, the second stage operation temperature can range from about 50 C to about 90 C, or from about 60 C to about 90 C, or from about 70 C to about 90 C, or from about 50 C to about 85 C, or from about 50 C to about 80 C, or from about 75 C
to about 85 C. The temperature can be selected depending on the paraffinic solvent that is used and, more particularly, depending on the boiling point of the paraffinic solvent. In addition, the operating pressure of the paraffinic treatment will vary depending on the solvent used and particularly depending on the vapor pressure of the solvent. An operator will be able to determine the temperature and pressure at which the paraffinic treatment should be performed once a solvent is selected, considering that the solvent should be kept in liquid state during the paraffinic treatment. In some implementations, the pressure in the second stage treatment can range from about 40 psi to about 300 psi, or from about 50 psi to about 300 psi. In other implementations, the pressure of the paraffinic stage can range from about 40 psi to about 200 psi. In some implementations, butane can be used as the paraffinic solvent and the paraffinic treatment can be performed at a temperature ranging from about 50 C to about 90 C, or from about 50 C to about 85 C, or from about 50 C to about 80 C. In further implementations, one can use butane as the solvent and the paraffinic treatment stage can be performed at a pressure of about 100 psi (about 700 kPa) to about 200 psi (about 1400 kPa) and at a temperature of about 50 to 80 C.

[00155] In some implementations, the quantity of paraffinic solvent added to the NFT
underflow or the stream derived therefrom to obtain the second stage feed stream, can be determined depending on the bitumen content of the stream, but also depending on the nature of the solvent. Furthermore, the quantity of paraffinic solvent to be used can depend on the aromatic content of the naphthenic diluent used in the first stage of the process, which, to some extent, is also present in the NFT overflow. As the aromatic components of the naphthenic diluent can dissolve asphaltenes, a greater quantity of paraffinic solvent may be required to precipitate asphaltenes when the concentration of aromatics in the naphthenic diluent is high. On the contrary, one can use smaller quantities of paraffinic solvent if the aromatic content of the naphthenic diluent is lower (e.g., up to about 10 wt%
aromatics). Thus, low-aromatic naphtha can help reduce the quantity of paraffinic solvent that is required, which can lead to various efficiencies and cost-savings.

[00156] In some implementations, the paraffinic solvent can be used to reach a solvent to bitumen ratio (S/B ratio) in the second stage feed stream of from about 0.5 to about 3.
In some implementations, the paraffinic solvent can be butane and the S/B
ratio can range from about 0.5 to about 1.5. In other implementations, the paraffinic solvent can be pentane and the S/B ratio can range from about 0.8 to about 2.5.

[00157] The asphaltene precipitation occurring in the second stage of the process can facilitate obtaining an asphaltene-reduced bitumen product (i.e., second stage overflow stream 26) in which the percentage of asphaltenes in the bitumen has been reduced compared to the percentage in the second stage feed. For instance, the bitumen in the second stage overflow can have an asphaltene content of less than about 15%.
As mentioned above, the proportion of asphaltenes that can be precipitated and thus the resulting percentage of asphaltenes in the asphaltene-reduced bitumen product recovered in the second stage of the process, can depend on the nature of the paraffinic solvent used. Hence, the lighter the paraffinic solvent, the more asphaltenes can be precipitated, resulting in less asphaltenes being present in the asphaltene-reduced bitumen product. In some implementations, depending on the paraffinic solvent used, the asphaltene content in the bitumen of the second stage overflow can range from about 1% to about 14% C5-asphaltenes. In further implementations, when the solvent used is butane or pentane, the percentage of asphaltenes in the bitumen recovered in the second stage overflow can be from about 7% to about 12% C5-asphaltenes.

[00158] Still referring to Fig. 1, in some implementations, the asphaltene-reduced bitumen second stage overflow 26 can be sent to a solvent recovery unit (SRU) 30 to recover the paraffinic solvent and produce a deasphalted bitumen stream 32. It is worth noting that the deasphalted bitumen stream 32 includes some naphtha diluent. The paraffinic solvent 20 recovered in the SRU can then be recycled to the paraffinic treatment stage. Where, the paraffinic treatment stage uses at least two settlers in counter-current configuration, the paraffinic solvent 20 can be recycled to the second stage of the paraffinic treatment plant. In further implementations, the second stage underflow 28 can be treated in a solvent and solids recovery unit to remove solids and recover any remaining solvent/diluent. For instance, the second stage under-flow stream 28 can be treated in a tailings solvent recovery unit (TSRU) to recover a tailings stream 42 mainly containing solids, water, asphaltenes, some residual bitumen and residual solvent/diluent, and an overhead stream 40 including diluent/solvent. In some implementations, the content in solvent/diluent in the tailings stream 42 can be lower than 4 parts of solvent/diluent per 1000 parts of bitumen in volume. Hence, the integration of the paraffinic treatment to the naphthenic treatment can allow reducing the solvent/diluent loss to the tailings, which, in turn, can improve tailings management as less solvent is discharged to tailings ponds.

[00159] Fig. 2 represents another implementation of the process, where the first stage and the second stage of the process are substantially similar to those presented in Fig. 1 and therefore can include the various features described above. According to the process of Fig. 2, the first stage can include mixing the bitumen froth 10 with the naphtha diluent 12 to form a naphtha diluted bitumen froth, which can then be treated in inclined plate separators in the NFT plant 14, to recover the naphtha diluted bitumen product 16 as the first stage overflow and the first stage underflow 18 including solids, water, some bitumen and naphtha diluent. Then, the paraffinic solvent 20 is added to the first stage underflow 18 and the resulting stream is sent to the second stage paraffinic treatment plant 24. In the second stage treatment, asphaltenes present in the first stage underflow 18 can be precipitated out in the presence of the paraffinic solvent and can be separated with the solids and water as the second stage underflow stream 28. The second stage overflow 26 including an asphaltene-reduced bitumen product diluted in the paraffinic solvent, can be sent to the SRU 30 to recover the paraffinic solvent and produce the deasphalted bitumen stream 32. The second stage underflow stream 28 can be sent to the TSRU 38 to recover the tailings stream 42 and the diluent/solvent overhead stream 40. In further implementations, the diluent/solvent overhead stream 40 can be sent to the SRU
30 for recovering additional paraffinic solvent 20, which can then be returned to the second stage plant 24 together with paraffinic solvent recovered from the second stage overflow 26.
Naphtha diluent present in the diluent/solvent overhead stream 40 produced in the TRSU
can be recovered with the deasphalted bitumen stream 32 exiting the SRU 30.

[00160] In another implementation of the process shown in Fig. 2, the deasphalted bitumen stream 32 recovered from the SRU 30 can be mixed with the NFT overflow stream 16 to provide the diluted bitumen product 34, which can be stored in the diluted bitumen tank 36 before being sent to upgrading operations. In further implementations, the deasphalted bitumen stream 32 can be diluted with additional naphtha before mixing with the NFT overflow stream 16. Adding naphtha diluent to the deasphalted bitumen stream 32 can enhance the mixing with the NFT overflow stream 16. The naphtha diluent added to the deasphalted bitumen stream 32 can be the same naphtha diluent as the one used in the NFT stage or can originate from another source.

[00161] In some implementations, the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream can have a base sediment and water (BS&VV) lower than 0.15 %, e.g., of about 0.1 % or lower. In some implementations, the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream can have a BS&W
of about 0.05%.

[00162] In some implementations, the diluted bitumen product 34 obtained by mixing the NFT overflow stream 16 with the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream, can have a BS&W that is lower than the BS&W of the NFT

overflow stream. The lowering of the BS&W of stream 34 can be attributed to the dilution factor and/or the fact that the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream has a low BS&W. In some implementations, the diluted bitumen product 34 can have a BS&W of about 1.5 % or lower. In other implementations, the diluted bitumen product 34 can have a BS&W of about 1 % or lower. The downstream upgrading operations can benefit from the reduction of the BS&W in the diluted bitumen product stream 34. Indeed, less water and solids can reduce overall erosion and corrosion on downstream equipment in the upgrading plant.

[00163] In some implementations, the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream can represent about 30% to about 70%
(e.g., about 35% to about 45%) of the diluted bitumen product 34. In other implementations, the NFT
overflow stream 16 can represent about 30% to about 65% (e.g., about 35% to about 65%), of the diluted bitumen product 34.

[00164] As explained above, a feature of the second stage paraffinic treatment is to precipitate asphaltenes from the second stage feed stream. Thanks to the asphaltene rejection, the resulting second stage overflow stream 26, and therefore the deasphalted bitumen stream 32, or the corresponding naphtha diluted stream, can present a low asphaltene content. In turn, the diluted bitumen product 34 obtained by mixing the deasphalted bitumen stream 32 or the corresponding naphtha diluted stream, with the NFT overflow stream 16, contains a lower asphaltene content than the NFT
overflow stream 16 itself. This can improve downstream upgrading operations in which the diluted bitumen product 34 is further treated to recover synthetic crude oil. For instance, the yield of the coking step in the upgrading operation can be increased thanks to the low asphaltene content upgrader feed.

[00165] Fig. 3 represents a further implementation of the process based on the example shown in Fig. 2 but including an additional step which can be performed upstream of the paraffinic treatment. More specifically, as can be seen in Fig. 3, bitumen froth derived from the bitumen froth stream 10 can be mixed in a controlled manner with the NFT
underflow stream 18 to obtain a secondary bitumen froth stream 44. Then, paraffinic solvent 20 can be added to the secondary bitumen froth stream 44 to obtain a second stage bitumen feed stream, which can then be treated in the paraffinic froth settlers of plant 24. In Fig. 3, the bitumen froth added to the first stage underflow stream 18 is from the same source as the bitumen froth 10 treated in the NFT plant 14. However, it could be possible to use a bitumen froth from a different extraction operation than the one from which bitumen froth derives.

[00166] The addition of bitumen froth to the NFT underflow stream 18 can facilitate higher bitumen and lower water content of the feed to the second stage, which can in turn improve asphaltene precipitation and water separation. This can facilitate production of a second stage overflow 26 that can meet downstream pipeline specifications.

[00167] In some implementations, the bitumen froth flow rate and/or the paraffinic solvent stream 20 flow rate can be controlled to adjust the S/B ratio in the second stage. As mentioned above, the S/B ratio in the second stage can vary between about 0.5 and about 3Ø When the paraffinic solvent is butane, the S/B ratio can range from about 0.5 to about 1.5. In the case of pentane, the S/B ratio can range from about 0.8 to about 2.5.

[00168] Fig. 4 represents another implementation of the process involving additional solids/liquid removal steps between the naphthenic treatment stage and the paraffinic treatment stage. More specifically, as seen in Fig. 4, the NFT underflow stream 18 can be pre-treated to remove at least a portion of the water and solids contained therein, before being subjected to asphaltene precipitation in the second stage. In some implementations, the pre-treatment can involve subjecting the NFT intermediate stream 18 to solids and water separation in a hydrocylcone plant including at least one stage of hydrocyclones 46a and optionally a second stage of hydrocyclones 46b. Each stage of hydrocyclones 46a and 46b can include a set of individual hydrocyclones. The two sets can be arranged in series as shown in Fig. 4. The second stage of hydrocyclones 46b, when used in the process, can be smaller in size than the first stage of hydrocyclones 46a.
Hence, the NFT
underflow stream 18 can be treated in hydrocyclones 46a, 46b to recover solids and water as streams 50a, 50b and a pre-treated bitumen-containing stream 48 depleted in solids and water, which can then be sent to the paraffinic treatment stage. In some implementations, the water and solids stream 50b, which also includes some bitumen and naphtha diluent can further be treated in the naphtha recovery unit (NRU) 52 to recover some naphtha diluent and NRU tailings. In some implementations, the naphtha diluent recovered from the NRU 52 can be recycled to a diluent pool or tankage and then be re-used in the first stage of the process and/or can be used to dilute the deasphalted bitumen stream 32 (not shown in the Figures).

[00169] Comparable advantages to those resulting from the addition of bitumen froth to the NFT underflow 18 can result from the removal of solids and water from the NFT
underflow 18 prior to the second stage treatment. This can allow for higher bitumen and lower water content in the feed to the second stage, which can in turn improve or facilitate asphaltene precipitation and water separation in the second stage paraffinic treatment.

[00170] In another implementation, the process can combine the features of the bitumen froth re-addition and the solids/water removal pre-treatment described above.
An implementation combining both these features is presented in Fig. 5. In this case, addition of the bitumen froth can be performed downstream the hydrocyclones treatment stage, which means that the stream receiving the bitumen froth in this case is the pre-treated bitumen-containing stream 48 depleted in solids and water. Although Fig. 5 shows that the bitumen froth added to the pre-treated bitumen-containing stream 48 derives from the bitumen froth treated in the NFT stage, the bitumen froth added to the pre-treated stream 48 could originate from a different extraction operation. The bitumen froth-containing stream 54 resulting from the addition of the fresh bitumen froth to the pre-treated bitumen-containing stream 48, can then be used for the second stage paraffinic treatment. Hence, paraffinic solvent 20 can be added to the bitumen froth-containing stream 54 and the resulting stream can be used as the second stage feed stream.

[00171] From the above description of various implementations of the process, one can note that the second stage feed stream, i.e., the stream that is subjected to the paraffinic treatment, can have different compositions depending on whether additional steps are performed downstream the NFT stage and before addition of the paraffinic solvent used for the second stage, and also on the nature of such additional steps. In Figs. 1 and 2, the second stage feed stream results from the direct combination of the NFT
underflow with the paraffinic solvent. In Fig. 3, the second stage feed stream results from the combination of the NFT underflow with fresh bitumen froth and further with paraffinic solvent. In Fig. 4, the second stage feed stream results from the combination of the solids/water depleted NFT underflow, i.e., pre-treated NFT underflow, with paraffinic solvent.
Finally, in Fig. 5, the second stage feed stream results from the combination of the pre-treated NFT

underflow with fresh bitumen froth and further with paraffinic solvent. In the configurations where fresh bitumen froth is added to the NFT underflow or the pre-treated NFT
underflow, the bitumen content of the second stage feed stream can be increased and, therefore, more paraffinic solvent can be required to promote asphaltene precipitation and enhance the separation process. Removal of solids and water before the second stage can facilitate improving the mixing of the pre-treated NFT underflow with the paraffinic solvent, which, in turn, can enhance the separation process. In addition, where bitumen froth is added to the NFT underflow before the second stage, the removal of solids and water before bitumen froth addition can allow reducing the total solids and water content in the second stage feed stream.

[00172] There are several advantages that can result from at least some of the implementations or features of the two-stage NFT-PT process described above compared to a conventional NFT process. Some advantages can be as follows:
- Operational/process flexibility to change the split between NFT overflow and underflow (e.g., from 70/30 to 30/70), so that the NFT overflow product quality can be improved.
- Enhanced bitumen product quality (e.g., with reduced chloride, water and solids), which benefits downstream upgrading or refinery reliability and utilization, and can reduce overall erosion and corrosion on downstream equipment in the upgrading plant.
- Simpler process with reduced use of high-maintenance and high operational cost rotating equipment (e.g., scroll and disk stacked centrifuge) and the use of low-maintenance static equipment (froth settling units).
- Potential increase of coker yield in upgrading operations, due to the asphaltene rejection during the paraffinic treatment, which results in lower asphaltene content in the bitumen feed to upgrader.
- Environmental benefit due to the reduction of the solvent (including naphtha and paraffinic) lost to tailings ponds.
- Lower energy (e.g., electricity) requirements resulting in reducing greenhouse gas emissions.

>

[00173] It is noted that in some implementations, an existing NFT facility can be retrofit to provide the NFT-PT two-stage system as described herein. The existing NFT
facility could be modified in terms of certain operational parameters and at least a portion of the underflow of the IPS's of the existing NFT facility could be fed directly or indirectly into a paraffinic treatment plant built for that purpose. Thus, a new PT plant could be integrated into an existing NFT facility. Alternatively, both an NFT plant and a PT plant to be built as an integrated facility to treat bitumen froth.

[00174] Another implementation of a process and system for recovering a deasphalted bitumen-containing product, involving the treatment of a naphtha diluted bitumen froth with a paraffinic solvent, is presented in Fig. 6. In this implementation, a naphtha diluent 12 is added to the bitumen froth 10 to form the naphtha diluted bitumen froth, which can be directly treated with the paraffinic solvent and then subjected to separation.
Hence, the paraffinic solvent 20 is added to the naphtha diluted bitumen froth and the combined stream 56 is separated in the paraffinic treatment plant 14 to recover a diluted bitumen product as the paraffinic treatment overflow 58 and a tailings stream as the paraffinic treatment underflow 60. Upon treatment with the paraffinic solvent, asphaltenes present in the bitumen can be precipitated out from the combined stream 56, separated from the bitumen phase in the separator, and recovered with the solids and water as the paraffinic treatment underflow 60. The paraffinic treatment overflow stream 58, which can be qualified as an asphaltene-reduced bitumen stream, includes bitumen, paraffinic solvent and naphtha.

[00175] The naphtha diluent used in the implementation represented in Fig. 6 can be a naphtha with low aromatic content (e.g., up to about 10 wt% aromatics). The low aromatic content can readily enhance asphaltene precipitation at lower solvent to bitumen ratios.

[00176] In some implementations, the naphtha diluent 12 can be added to the bitumen froth 10 to reach a diluent to bitumen ratio (D/B ratio) ranging from about 0.1 to about 0.4.
The addition of naphtha to the bitumen froth prior to the paraffinic treatment can facilitate reducing the viscosity of the bitumen in the froth, which in turn can allow better control of the settling rate / deasphalting in the paraffinic treatment process, especially for lighter paraffinic solvents. The naphtha diluent can also contribute to lower viscosity of the final product, which can meet pipeline specification (e.g., API > 21.5), while providing a reasonably fast settling rate at the FSU.

[00177] The paraffinic solvent used in the implementation represented in Fig.
6 can be a C4 or C5-alkane, i.e., n-butane, iso-butane, n-pentane, iso-pentane or any mixture thereof.
In a particular implementation, the paraffinic solvent can include n-butane, iso-butane or a mixture thereof. The use of a C4-alkane as the paraffinic solvent can be advantageous over a C5-alkane since lower quantities of C4-alkane would be required while still achieving a suitable separation. Using butane as the solvent can facilitate obtaining an asphaltene-reduced bitumen stream 58 with low water and solids contents. For instance, the water content in the asphaltene-reduced bitumen stream 58 can be less than about 1000 ppm water and the solids content can be less than about 500 ppm. In some implementations, the make-up paraffinic solvent used in the process, e.g, butane, can be produced and supplied from an upgrading operation.

[00178] In some implementations, the paraffinic treatment of the naphtha diluted bitumen froth can be performed at temperatures ranging from about 50 C to about 90 C, or from about 50 C to about 80 C, from about 60 C to about 90 C, or from about 70 C to about 90 C. In addition, the operation pressure of the paraffinic treatment can range from about 50 psi to about 200 psi. Where butane is used as the solvent, the paraffinic treatment stage can be performed at a pressure of from about 100 psi to about 200 psi (about 700 kPa to about 1400 kPa) and at a temperature of from about 50 C to about 80 C.

[00179] In some implementations, the paraffinic solvent, such as butane, can be added to the naphtha diluted bitumen froth to reach a solvent to bitumen ratio (SIB
ratio) in the combined stream 56 of from about 0.5 to about 1.5. As mentioned above, if the paraffinic solvent would be pentane, greater quantities of solvent would be required in the paraffinic separation stage and the S/B ratio could be up to about 2.5.

[00180] The asphaltene precipitation of the paraffinic treatment stage can facilitate obtaining an asphaltene-reduced bitumen product (i.e., overflow stream 58) in which the percentage of asphaltenes in the bitumen has been reduced compared to the percentage in the combined stream 56. For instance, if the solvent used is butane or pentane, the percentage of asphaltenes in the bitumen recovered in the paraffinic treatment overflow 58 can be from about 7% to about 12% C5-asphaltenes.

[00181] Still referring to Fig. 6, in some implementations, the asphaltene-reduced bitumen overflow 58 can be sent to a solvent recovery unit (SRU) 30 to recover the paraffinic solvent and produce a deasphalted bitumen stream 62 containing some naphtha.
The paraffinic solvent 20 recovered in the SRU can then be recycled to the paraffinic treatment stage. In further implementations, the paraffinic treatment underflow 60 can be treated in a solvent and solids recovery unit to remove solids and recover any remaining solvent/diluent. For instance, the underflow stream 60 can be treated in a TSRU to recover a tailings stream 66 mainly containing solids/water, asphaltene, some residual bitumen and traces of solvent/diluent, and an overhead stream 64 including diluent/solvent.

[00182] The deasphalted bitumen stream 62 can have a base sediment and water (BS&W) lower than 0.15 %, e.g., lower than 0.1 %. In some implementations, the deasphalted bitumen stream 62 can have a BS&W of about 0.1% or even less at about 0.05%. Therefore, the direct separation treatment of a naphtha diluted bitumen froth using butane or pentane can allow obtaining a deasphalted bitumen product with low water and solids contents. Moreover, since the deasphalted bitumen product 62 also contains naphtha, this bitumen product can meet downstream pipeline specifications and can be suitable for being directly sent to upgrading operations without needing to add any condensate, as is required for deasphalted bitumen product recovered from conventional PET operations.

[00183] The implementation presented in Fig 6 can thus allow obtaining a bitumen product of good quality (e.g., with low water and solids content), which benefits to downstream upgrading or refinery reliability and utilization, and can reduce overall erosion and corrosion on downstream equipment in the upgrading plant. The process can be easily implemented with the simple use of low-maintenance static equipment (e.g., froth settling units).

[00184] In a further implementation, the combined naphthenic and paraffinic process can be used to treat a bitumen-containing emulsion deriving from an in situ operation or an emulsion including a mixture of a bitumen froth and a bitumen emulsion deriving from an in situ operation.

[00185] In one implementation shown in Fig. 7, naphtha diluent 12 is added to a bitumen emulsion 110 recovered from an in situ operation, to form a naphtha diluted emulsion 112, which can then be treated with the paraffinic solvent and then subjected to separation.
Hence, naphtha diluent 12 is added to the in situ recovered bitumen emulsion 110 and the resulting diluted bitumen emulsion 112 can then receive the paraffinic solvent 20 to form the stream which is fed to the paraffinic treatment plant 14. Upon treatment with the paraffinic solvent, asphaltenes present in the bitumen can be precipitated out from the diluted bitumen emulsion stream 112, separated from the bitumen phase in the separator, and recovered with the solids and water as the paraffinic treatment underflow 116. The paraffinic treatment overflow stream 114, which can be qualified as an asphaltene-reduced bitumen stream, includes bitumen, paraffinic solvent and naphtha.
Still referring to Fig. 7, in some implementations, the asphaltene-reduced bitumen overflow 114 can be sent to a solvent recovery unit (SRU) 30 to recover the paraffinic solvent and produce a deasphalted bitumen stream 122 containing some naphtha. The paraffinic solvent recovered in the SRU can then be recycled to the paraffinic treatment stage.
In further implementations, the paraffinic treatment underflow 116 can be treated in a solvent and solids recovery unit to remove solids and recover any remaining solvent/diluent. For instance, the underflow stream 116 can be treated in a TSRU to recover a tailings stream 120 mainly containing solids/water, asphaltene, some residual bitumen and traces of solvent/diluent, and an overhead stream 118 including diluent/solvent.

[00186] In the implementation shown in Fig. 8, the bitumen emulsion 110 recovered from an in situ operation is mixed with a bitumen froth 10 to form a mixed emulsion 124 including bitumen, water and solids. In some implementations (not shown in the figure), some naphtha can be added to the bitumen emulsion 110 produced from the well pairs before mixing with the bitumen froth 10 for reducing the viscosity of the bitumen in the emulsion, which in turn can facilitate pipelining up to the emulsion/froth treatment plant. Once the bitumen emulsion 110 is mixed with the bitumen froth 10, naphtha diluent 12 is added to the mixed emulsion 124 and the resulting stream is fed to the naphthenic treatment plant (NFT) 14. In some implementations, the NFT 14 can include gravity settlers including inclined plate separators. In the NFT, the naphtha diluted mixed emulsion is separated into the naphtha diluted bitumen product 126 as the NFT overflow and the NFT
underflow 128 including solids, water, some bitumen and naphtha diluent. Then, the paraffinic solvent 20 is added to the NFT underflow 128 and the resulting stream is sent to the paraffinic treatment plant (PTP) 24. In the PTP, asphaltenes present in the underflow 128 can be precipitated out and separated with the solids and water as the PTP
underflow stream 132. The PTP overflow 130 including an asphaltene-reduced bitumen product diluted in the paraffinic solvent, can be sent to the SRU 30 to recover the paraffinic solvent and produce the deasphalted bitumen stream 138. The PTP underflow stream 132 can be sent to the TSRU 38 to recover the tailings stream 136 and the diluent/solvent overhead stream 134. In further implementations (not shown in Fig. 8), the diluent/solvent overhead stream 134 can be sent to the SRU 30 for recovering additional paraffinic solvent 20, which can then be returned to the PTP together with paraffinic solvent recovered from the PTP
overflow 130. In further implementations, naphtha diluent present in the diluent/solvent overhead stream 134 produced in the TRSU can be recovered with the deasphalted bitumen stream 138 exiting the SRU 30. In another implementation (not shown in Fig. 8), the deasphalted bitumen stream 138 can be mixed with the NFT overflow stream 126 to provide a diluted bitumen product, which can be stored in the diluted bitumen tank 36 before being sent to upgrading operations.

[00187] The in situ operation shown in Figs. 7 and 8 can involve injecting a mobilizing fluid 100 via an injection well into a bitumen-containing underground reservoir to recover an emulsion 110 mainly including bitumen, water and some solids. In some implementations, the mobilizing fluid 100 can be steam and/or water. For instance, the in situ operation can be a steam assisted gravity drainage (SAGD) operation, performed in horizontal well pairs. Alternatively, the in situ operation can involve injecting a solvent as the mobilizing fluid 100 or a mixture of solvent and steam. When a solvent is injected into the underground reservoir to mobilize the bitumen therein, the solvent is advantageously a non-precipitating solvent, i.e., a solvent which does not result in asphaltene precipitation in situ or which only precipitates asphaltenes to a limited extent.

[00188] In some implementations, the naphtha diluent used in the implementation represented in Figs. 7 and 8 can be a naphtha with low aromatic content. The low aromatic content can readily enhance asphaltene precipitation at lower solvent to bitumen ratios.

[00189] In some implementations, the naphtha diluent 12 can be added to the bitumen emulsion 110 (Fig. 7) or to the combined bitumen froth / in situ emulsion stream 124 (Fig.
8) to reach a diluent to bitumen ratio (D/B ratio) ranging from about 0.1 to about 0.4. The addition of naphtha to the bitumen emulsion 110 or to the combined stream 124 prior to the paraffinic treatment can facilitate reducing the viscosity of the bitumen in the froth, which in turn can allow better control of the settling rate / deasphalting in the paraffinic treatment process, especially for lighter paraffinic solvents.

[00190] The paraffinic solvent used in the implementation represented in Figs.
7 and 8 can be a C4 or C5-alkane, i.e., n-butane, iso-butane, n-pentane, iso-pentane or any mixture thereof. In a particular implementation, the paraffinic solvent can include n-butane, iso-butane or a mixture thereof. The use of a C4-alkane as the paraffinic solvent can be advantageous over a C5-alkane since lower quantities of C4-alkane would be required while still achieving a suitable separation. Using butane as the solvent can facilitate obtaining an asphaltene-reduced bitumen stream 114 or 130 with low water and solids contents. For instance, the water content in the asphaltene-reduced bitumen stream 114 or 130 can be less than about 1000 ppm water and the solids content can be less than about 500 ppm. In some implementations, the make-up paraffinic solvent used in the process, e.g, butane, can be produced and supplied from an upgrading operation.

[00191] The paraffinic treatment in the implementations of Figs. 7 and 8 can be performed at similar temperatures than for the other implementations previously resented. For instance, the temperature of the paraffinic treatment can range from about 50 C to about 90 C, or from about 50 C to about 80 C, from about 60 C to about 90 C, or from about 70 C to about 90 C. In addition, the operation pressure of the paraffinic treatment can range from about 50 psi to about 200 psi. Where butane is used as the solvent, the paraffinic treatment stage can be performed at a pressure of from about 100 psi to about 200 psi (about 700 kPa to about 1400 kPa) and at a temperature of from about 50 C to about 80 C.

[00192] In some implementations, the paraffinic solvent 20, such as butane, can be added to reach a solvent to bitumen ratio (S/B ratio) in stream 112 or 128 of from about 0.5 to about 1.5. As mentioned above, if the paraffinic solvent would be pentane, greater quantities of solvent would be required in the paraffinic separation stage and the S/B ratio could be up to about 2.5.

[00193] The asphaltene precipitation of the paraffinic treatment stage can facilitate obtaining an asphaltene-reduced bitumen product (i.e., stream 114 or 130) in which the percentage of asphaltenes in the bitumen has been reduced. For instance, if the solvent used is butane or pentane, the percentage of asphaltenes in the bitumen recovered in the paraffinic treatment overflow 114 or 130 can be from about 7% to about 12% C5-asphaltenes.

[00194] The deasphalted bitumen stream 122 or 138 can have a base sediment and water (BS&W) lower than 0.15 %, e.g., lower than 0.1 %. In some implementations, the deasphalted bitumen stream 122 or 138 can have a BS&W of about 0.1% or even less at about 0.05%. In addition, the deasphalted bitumen product 122 or 138, which contains naphtha, can meet downstream pipeline specifications and can be suitable for being directly sent to upgrading operations without needing to add any condensate, as is required for deasphalted bitumen product recovered from conventional PFT
operations, or for direct transport of bitumen emulsions recovered from in situ operations.
EXPERIMENTATION

[00195] Experimental tests were performed to provide information on settling rate and bitumen product quality, including water and solids content, and asphaltene rejection, upon treatment of various bitumen froth-containing samples according to the present technology.

[00196] Three different bitumen froth-containing samples were tested, each one having a specific naphtha content. More particularly, the following samples were tested:
- sample which would correspond to stream 48 in Fig. 4, identified as "Cyclone 0/F";
- sample which would correspond to stream 18 in Figs. 1 or 2, identified as "IPS U/F";
- sample which would correspond to stream 44 in Fig. 3, identified as "IPS/froth".

[00197] IPS/froth samples having three different ratios of IPS U/F to re-added froth (e.g., weight ratios between stream 18 and stream 10) were tested. The ratios IPS U/F
to re-added froth were 0.8, 1.4 and 2Ø

[00198] The paraffinic solvent used in the testing was butane. Butane was added at various solvent to bitumen (S/B) ratios for each tested sample.

[00199] Tests were carried out in a stainless-steel autoclave cell (Parr Instruments Co.TM) with a glass side window. The autoclave has a volume of approximately 600 ml, an inner diameter of 63 mm and a height of 200 mm. The autoclave cell is equipped with four baffles and two coupled 35 mm diameter turbine impellers for mixing.

[00200] The required amount of froth was first added to the autoclave. Unless mentioned otherwise, the froth in the autoclave was heated to the target temperature of 80 C while mixing at a speed of about 600 rpm. Butane was also heated to the testing temperature.
Once the required temperature was reached, butane was injected into the autoclave by pressure difference and the mixing was continued for about 15 minutes. The mixer was then turned off to allow the asphaltene aggregates to settle. During settling, the asphaltene-supernatant interface was monitored and recorded using a video camera.
After the asphaltene settling was complete, the top supernatant phase was collected through a dip tube into a sample collection cylinder for further analysis.
Once the supernatant sample was collected, the autoclave was cooled to ambient temperature followed by depressurization (i.e., bleeding off butane) to ambient pressure.
The autoclave was then opened and the underflow (sediment) was also collected and analyzed for its composition and asphaltene content.

[00201] The water, mineral solids and bitumen contents were determined by Dean Stark extraction. The toluene-diluted bitumen from the Dean Stark extraction was collected and the toluene and light-end of the naphtha was removed by rotary evaporation (rotavap).
The resulting bitumen sample was then used to measure the asphaltene content.
The naphtha content in the bitumen was estimated from density measurements.

[00202] The experimentation results are presented in Table 1.

[00203] The data in Table 1 shows that the settling rates for industrial-scale applications are achievable. The results from the tests also show the product quality (e.g., KF H20 and filterable solids contents) exceeds the pipeline requirements. The process data also indicates the product quality meets marketable product API and viscosity requirements.

w [00204] Table 1 ,1 1-.
w 0 Target S/B Froth Feed Settling rate KF H20 in Filterable C5-Asphaltene in r.) (C4/bitumen) (mm/min) C4-removed solids bitumen product K) overflow *
(PPal) (wt%) 1 (wt%) 1-.
' 1.2 Cyclone OF 371 0.02 213 9.2 r.) ,1 1.0 Cyclone OF 90 0.01 208 12.9 0.8 Cyclone OF 33 0.01 778 14.7 1.2 IPS U/F 185 0.01 196 11.0 1.5 IPS U/F >1000 0.01 105 6.0 1.2 IPS/Froth 0.8 -1000 0.01 124 7.3 (,) 1.2 IPS/Froth 1.4 -1000 0.01 125 7.9 co 1.2 IPS /froth 2.0 >1000 0.01 190 8.4 1.1 IPS /froth 0.8 980 0.01 185 9.3 1.1 IPS /froth 1.4 -1000 0.01 162 9.6 1.1 IPS /froth 2.0 -1000 0.01 216 9.8 1.0 IPS /froth 0.8 463 0.01 242 11.8 1.0 IPS /froth 1.4 300 0.01 177 11.9 1.0 IPS /froth 2.0 237 0.01 177 12.1 1.2 IPS /froth 0.8, 70 C >1000 0.01 167 7.2 1.2 IPS /froth 0.8, 90 C -1000 0.01 114 6.9 * KF = Karl Fisher method for H20 content measurement

Claims (23)

40

1. A process for reducing a base sediment and water (BS&VV) of a diluted bitumen stream recovered as an overflow of a naphthenic froth treatment, comprising blending the diluted bitumen stream with a deasphalted bitumen stream recovered from a paraffinic froth treatment to produce a diluted bitumen product.

2. The process of claim 1, wherein the diluted bitumen stream is recovered as an overflow of a naphthenic froth treatment gravity settler.

3. The process of claim 1 or 2, wherein the deasphalted bitumen stream is recovered from a solvent recovery unit of the paraffinic froth treatment.

4. The process of any one of claims 1 to 3, further comprising adding naphthenic diluent to the deasphalted bitumen stream before blending with the diluted bitumen stream.

5. The process of any one of claims 1 to 4, wherein the deasphalted bitumen stream has BS&W of about 0.1 % or lower.

6. The process of any one of claims 1 to 5, wherein the diluted bitumen product resulting from the blending has a BS&W of about 1.5 % or lower.

7. The process of any one of claims 1 to 6, wherein the diluted bitumen product resulting from the blending has a BS&W of about 1 % or lower.

8. The process of any one of claims 1 to 7, wherein the deasphalted bitumen stream represents about 30% to about 70% of the diluted bitumen product.

9. The process of any one of claims 1 to 8, wherein the diluted bitumen stream represents about 35% to about 65% of the diluted bitumen product.

10. The process of any one of claims 1 to 9, wherein the paraffinic froth treatment employs at least one alkane in the 03 to 08 range as paraffinic solvent.
Date Recue/Date Received 2022-04-12

11. The process of claim 10, wherein the paraffinic solvent comprises butane, pentane or any mixture thereof.

12. The process of claim 10 or 11, wherein the paraffinic solvent comprises n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.

13. The process of claim 12, wherein the paraffinic solvent comprises n-butane, iso-butane or any mixture thereof.

14. A process for reducing an asphaltene content of a diluted bitumen stream recovered as an overflow of a naphthenic froth treatment, comprising blending the diluted bitumen stream with a deasphalted bitumen stream recovered from a paraffinic froth treatment to produce a diluted bitumen product.

15. The process of claim 14, wherein the diluted bitumen stream is recovered as an overflow of a naphthenic froth treatment gravity settler.

16. The process of claim 14 or 15, wherein the deasphalted bitumen stream is recovered from a solvent recovery unit of the paraffinic froth treatment.

17. The process of any one of claims 14 to 16, further comprising adding naphthenic diluent to the deasphalted bitumen stream before blending with the diluted bitumen stream.

18. The process of any one of claims 14 to 17, wherein the deasphalted bitumen stream represents about 30% to about 70% of the diluted bitumen product.

19. The process of any one of claims 14 to 18, wherein the diluted bitumen stream represents about 35% to about 65% of the diluted bitumen product.

20. The process of any one of claims 14 to 19, wherein the paraffinic froth treatment employs at least one alkane in the 03 to 08 range as paraffinic solvent.
Date Recue/Date Received 2022-04-12

21. The process of claim 20, wherein the paraffinic solvent comprises butane, pentane or any mixture thereof.

22. The process of claim 20 or 21, wherein the paraffinic solvent comprises n-butane, isobutane, n-pentane, iso-pentane or any mixture thereof.

23. The process of claim 20, wherein the paraffinic solvent comprises n-butane, iso-butane or any mixture thereof.
Date Recue/Date Received 2022-04-12