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Effects of Clay Wettability and Process Variables on Separation of

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					Effects of Clay Wettability and Process
  Variables on Separation of Diluted
           Bitumen Emulsion

              Tianmin Jiang
             George Hirasaki
              Clarence Miller



             Consortium Meeting
               Rice University
                 05/03/2010
           Surface mining of Canadian
                    oil sands
 • Mining and transportation to the extraction plant
 • Oil sands mixed with hot water to form a slurry containing
   air bubbles, water, bitumen, solids
 • Flotation vessels used to obtain a froth
       (60% bitumen, 30 % water, 10% fine solids)
 • Bitumen diluted with light solvents for final separation

 Desired Goal:    minimize residual water in oil
                  minimize residual fine solid


During the final separation stage, stable water-in-oil emulsions
persist due to the clay solids and asphaltenes.
             Project Objectives



• Study the effect of clay solids and characterize
  rag layer.

• Obtain emulsion separation with appropriate
  chemicals and proper procedure.
           Emulsion Preparation

• Start with bitumen froth with water and clay solids

• Dilute with naphtha with different dilution ratios

• Synthetic brine: 25 mM NaCl, 15 mM NaHCO3, 2 mM
  Na2SO4, 0.3 mM CaCl2 and 0.3 mM MgCl2

• Diluted bitumen and brine (1: 1, v/ v) emulsified with
  paddle wheel at 3,600 RPM, 10 min
                                      Prior work
                  Effect of clay solids and PR5
                                     12 h emulsions




With solids, No PR5                                                     No solids, No PR5
                               1 w.% NaCl, pH 6.8, 25 ºC




With solids and PR5   PR5 will help emulsions coalescence, clays will   No solids, With PR5
                      make the emulsion more stable.
      Rag Layer
                                   Rag layer
                      Emulsions 12 h after adding 200 ppm PR5, 25 ºC




    No clay                  With clay               With clay       With clay and silicate
pH:   6.8                       6.8                     8.3                    8.5




 The rag layer is a mixture of partially oil-wet solids, oil and w/o emulsion. The solids
 are held together by oil and emulsion, with intermediate density, which lies near the
 top of the aqueous phase.
           Effects of dilution ratio

• Emulsion preparation with N/B ratio 0.7 and 4.0.
• Temperature at 80 ºC.
• Measuring water and solid content (K-F titration
  and centrifugation) in oil layer.
• Solid distribution in different layers of emulsion.
• Finding effects of dilution ratio and silicate.
• Wettability difference of clay in different layers
  of emulsion.
  Effects of dilution ratio
                  24 h emulsion

                   200 ppm demulsifier
Control   PR1     PR2     PR3      PR4      PR5         PR6



                                           Oil layer



                                           Rag layer


                                         Bottom layer

                Dilution ratio N/B = 0.7




                Dilution ratio N/B = 4.0
                                           Emulsion separation with
                                            N/B ratio 4.0, no solids
                                                                                                       Top oil layer

                                                                                                      Middle oil layer

                                                                                                     Bottom oil layer




Control                                    PR1         PR2         PR3          PR4   PR5      PR6        6057
                                                 6 h emulsion adding 200 ppm demulsifier, pH 8.3
                                 8
 Water/ solid content in oil %




                                       Water on top oil layer
                                       Water in middle oil layer
                                       Water at bottom oil layer
                                 6

                                                                                      Emulsion with 200 ppm
                                 4                                                    PR4 has best separation.

                                 2


                                 0
                                     PR4      PR5      PR6               6057
                                            200 ppm Demulsifier
                   Emulsion separation with
                     N/B ratio 4.0, pH 8.3
                                                        24 h emulsion




Control   PR1     PR2     PR3     PR4    PR5    PR6
                  200 ppm demulsifier




                                                       Control   50 ppm 100 ppm 200 ppm
                                                                 Demulsifier 6057




Control   7821   7822    256      256A   256B   256C
                 200 ppm demulsifier
                                                                 Water/ solid content in oil
                                                             and solid distribution, N/B ratio 4.0
                                                5                                                                                5                                                                                 5
                Water/ solid content in oil %




                                                              Water in middle oil layer                                                         Water in middle oil layer                                                        Water in middle oil layer




                                                                                                        Water content in oil %




                                                                                                                                                                                          Water content in oil %
                                                4             Water at bottom oil layer                                          4              Water at bottom oil layer                                          4             Water at bottom oil layer
                                                              Solid in oil layer                                                                Solid in oil layer                                                               Solid in oil layer
                                                3                                                                                3                                                                                 3

                                                2                                                                                2                                                                                 2

                                                1                                                                                1                                                                                 1

                                                0                                                                                0                                                                                 0
                                                     PR3      PR4     PR5         PR6                                                 7822     256A     256B       256C                                                 50 ppm     100 ppm       200 ppm
                                                           200 ppm Demulsifier                                                               200 ppm Demulsifier                                                                 6057 Dosage
                              100                                                                                    100                                                                               100
                                                                         Oil layer                                                                         Oil layer                                                                        Oil layer
                                                                         Rag layer                                                                         Rag layer                                                                        Rag layer
Solid distrbution %




                                                                                          Solid distrbution %




                                                                                                                                                                            Solid distrbution %
                                                80                                                                               80                                                                                80
                                                                         Bottom layer                                                                      Bottom layer                                                                     Bottom layer
                                                60                                                                               60                                                                                60

                                                40                                                                               40                                                                                40

                                                20                                                                               20                                                                                20

                                                0                                                                                0                                                                                 0
                                                     PR3      PR4     PR5         PR6                                                 7822     256A     256B       256C                                                 50 ppm     100 ppm       200 ppm
                                                           200 ppm Demulsifier                                                               200 ppm Demulsifier                                                                 6057 Dosage

                                                      Sample adding PR5 has lowest water in oil layer; sample adding PR6 has
                                                      lowest solid in oil layer.
Effect of Na2SiO3 with N/B ratio 4.0
   Control   PR5    PR6   7822     256C           6057
                   200ppm                 50 ppm 100 ppm 200 ppm




       24 h emulsion adding 1×10-4 M silicate (12 ppm), pH 8.5




       24 h emulsion adding 2×10-4 M silicate (24 ppm), pH 8.8




       24 h emulsion adding 4×10-4 M silicate (49 ppm), pH 9.1
                                                Water/ solid content in oil
                                                   with N/B ratio 4.0
                                        Water in middle oil layer
                         5                                                                   5
                                        Water at bottom oil layer
                                                                                                        Water in middle oil layer
                                        Solid in oil layer
Water content in oil %




                                                                    Water content in oil %
                         4                                                                   4          Water at bottom oil layer   Sample adding 200
                                              50
                                              ppm
                                                     100
                                                     ppm
                                                            200
                                                            ppm
                                                                                                        Solid in oil layer          ppm PR5 and 4×10-4
                         3                                                                   3                    50    100   200
                                                                                                                  ppm   ppm   ppm   M silicate has the
                         2                                                                   2                                      lowest residual
                                                                                                                                    water and solid in
                         1                                                                   1
                                                                                                                                    oil.
                         0                                                                   0
                          PR5 PR6 7822 256C 6057 6057 6057                                    PR5 PR6 7822 256C 6057 6057 6057
                                200 ppm Demulsifier                                                 200 ppm Demulsifier
                                   No silicate                                                   Adding 1×10-4 M silicate

                         5                                                                   5
                                    Water in middle oil layer                                           Water in middle oil layer
Water content in oil %




                                                                    Water content in oil %




                         4          Water at bottom oil layer                                4          Water at bottom oil layer
                                    Solid in oil layer                                                  Solid in oil layer          Residual water and
                         3                    50
                                              ppm
                                                     100
                                                     ppm
                                                            200
                                                            ppm
                                                                                             3                    50
                                                                                                                  ppm
                                                                                                                        100
                                                                                                                        ppm
                                                                                                                              200
                                                                                                                              ppm   solid content
                         2                                                                   2
                                                                                                                                    decreases with
                                                                                                                                    increase of silicate
                         1                                                                   1                                      concentration.
                         0                                                                   0
                          PR5 PR6 7822 256C 6057 6057 6057                                    PR5 PR6 7822 256C 6057 6057 6057
                                200 ppm Demulsifier                                                 200 ppm Demulsifier
                             Adding 2×10-4 M silicate                                            Adding 4×10-4 M silicate
                                                 Solid distribution in different
                                                   layers with N/B ratio 4.0
                      100                                                          100
                                            Oil layer                                                    Oil layer
                                            Rag layer                                                    Rag layer
Solid distrbution %




                                                             Solid distrbution %
                      80                                                           80
                                            Bottom layer                                                 Bottom layer

                      60                   50
                                           ppm
                                                 100
                                                 ppm
                                                       200
                                                       ppm
                                                                                   60                   50
                                                                                                        ppm
                                                                                                                100
                                                                                                                ppm
                                                                                                                      200
                                                                                                                      ppm


                      40                                                           40

                      20                                                           20

                       0                                                            0                           With increase of
                        PR5 PR6 7822 256C 6057 6057 6057                             PR5 PR6 7822 256C 6057 6057 6057
                              200 ppm Demulsifier                                          200 ppm Demulsifier
                                                                                                                silicate concentration,
                                  No silicate                                          Adding 1×10-4 M silicate
                                                                                                                less solids stay in oil
                      100                                                          100                          and more solids settle
                                             Oil layer                                                Oil layer
                                             Rag layer                                                Rag layer to the bottom.
Solid distrbution %




                                                             Solid distrbution %




                      80                                                            80
                                             Bottom layer                                                    Bottom layer

                      60                   50
                                           ppm
                                                 100
                                                 ppm
                                                       200
                                                       ppm
                                                                                   60                  50
                                                                                                       ppm
                                                                                                               100
                                                                                                               ppm
                                                                                                                      200
                                                                                                                      ppm


                      40                                                           40

                      20                                                           20

                       0                                                            0
                        PR5 PR6 7822 256C 6057 6057 6057                             PR5 PR6 7822 256C 6057 6057 6057
                              200 ppm Demulsifier                                          200 ppm Demulsifier
                            Adding 2×10-4 M silicate                                     Adding 4×10-4 M silicate
                                          Emulsion separation with
                                           N/B ratio 0.7, no solids




Control                                   PR1        PR2          PR3          PR4   PR5      PR6   6057
                                                24 h emulsion adding 200 ppm demulsifier, pH 8.3
                                8
Water/ solid content in oil %




                                      Water on top oil layer
                                      Water in middle oil layer
                                      Water at bottom oil layer
                                6

                                                                                     Emulsion with 200 ppm
                                4                                                    6057 has better separation
                                                                                     than others.
                                2


                                0
                                    PR3       PR4      PR5              6057
                                            200 ppm Demulsifier
 Emulsion separation with
   N/B ratio 0.7, pH 8.3
                     24 h emulsion




Control   PR1        PR2     PR3         PR4   PR5   PR6
                     200 ppm demulsifier




           Control    50 ppm 100 ppm 200 ppm
                      Demulsifier 6057
Effect of Na2SiO3 with N/B ratio 0.7
     Control    PR3     PR4      PR5      PR6      6057 (200 ppm demulsifier)




    24 h emulsion adding 1×10-4 M silicate (12 ppm), pH 8.5




    24 h emulsion adding 2×10-4 M silicate (24 ppm), pH 8.8




    24 h emulsion adding 4×10-4 M silicate (49 ppm), pH 9.1
                                                                  Water/ solid content in oil
                                                                     with N/B ratio 0.7
                                8                                                                              8
Water/ solid content in oil %




                                                                               Water/ solid content in oil %
                                                   Water on top oil layer                                                         Water on top oil layer
                                                   Water in middle oil layer
                                                   Solid in oil layer
                                                                                                                                  Water in middle oil layer
                                                                                                                                  Solid in oil layer
                                                                                                                                                              Sample adding 200
                                6                                                                              6
                                                                                                                                                              ppm PR5 and 4×10-4 M
                                4                                                                              4
                                                                                                                                                              silicate has lowest
                                                                                                                                                              residual water content
                                2                                                                              2                                              in oil.

                                0                                                                              0
                                    PR3   PR4    PR5    PR6           6057                                         PR3   PR4    PR5    PR6           6057
                                          200 ppm Demulsifier                                                            200 ppm Demulsifier
                                           No silicate                                                             Adding 1×10-4 M silicate

                                8                                                                              8
Water/ solid content in oil %




                                                                               Water/ solid content in oil %




                                                   Water on top oil layer                                                         Water on top oil layer
                                                   Water in middle oil layer                                                      Water in middle oil layer
                                                   Solid in oil layer                                                             Solid in oil layer
                                6                                                                              6                                              Residual water and
                                                                                                                                                              solid content
                                4                                                                              4
                                                                                                                                                              decreases with
                                                                                                                                                              increase of silicate
                                2                                                                              2
                                                                                                                                                              concentration.
                                0                                                                              0
                                    PR3   PR4    PR5    PR6           6057                                         PR3   PR4    PR5    PR6           6057
                                          200 ppm Demulsifier                                                            200 ppm Demulsifier
                                    Adding 2×10-4 M silicate                                                       Adding 4×10-4 M silicate
                                                  Solid distribution in different
                                                    layers with N/B ratio 0.7
                      100                                                             100
                                                 Oil layer                                                       Oil layer
                                                 Rag layer                                                       Rag layer
Solid distrbution %




                                                                Solid distrbution %
                      80                                                              80
                                                 Bottom layer                                                    Bottom layer

                      60                                                              60

                      40                                                              40

                      20                                                              20
                                                                                                                                With increase of
                       0                                                               0
                            PR3   PR4    PR5   PR6
                                  200 ppm Demulsifier
                                                        6057                                PR3   PR4    PR5   PR6
                                                                                                  200 ppm Demulsifier
                                                                                                                        6057    silicate concentration,
                                   No silicate                                              Adding 1×10-4 M silicate            less solids stay in oil
                      100                                                             100                                       and more solids settle
                                                 Oil layer                                                       Oil layer
                                                 Rag layer                                                       Rag layer
                                                                                                                                to the bottom.
Solid distrbution %




                                                                Solid distrbution %




                      80                                                              80
                                                 Bottom layer                                                    Bottom layer

                      60                                                              60

                      40                                                              40

                      20                                                              20

                       0                                                               0
                            PR3   PR4    PR5   PR6      6057                                PR3   PR4    PR5   PR6      6057
                                  200 ppm Demulsifier                                             200 ppm Demulsifier

                            Adding 2×10-4 M silicate                                        Adding 4×10-4 M silicate
                   Asphaltene content in solid
                from different layers of emulsion

      Sample                                   Emulsion with N/B 4.0,
                       Emulsion with N/B 4.0                          Emulsion with N/B 0.7
                                                200 ppm 6057 and
                        and 200 ppm 6057                               and 200 ppm 6057
                                                 4×10-4 M silicate
 Asphaltene % in                32                      29                     37
solid from oil layer
 Asphaltene % in                20                      20                     28
solid from rag layer
 Asphaltene % in                14                      15                     20
 solid from bottom

Solid in emulsion has oil-wet sequence: in oil layer > in rag layer > at bottom layer.

Solid has asphaltene content: in oil layer > in rag layer > at bottom layer.

At the same layer, sample with N/B ratio 0.7 has higher asphaltene content in
solid than that with N/B ratio 4.0.
                  Effect of N/B ratio
• Emulsion with N/B ratio 0.7 is more stable than that with
  N/B ratio 4.0 at 80 ºC.
• Residual water and solid in oil with N/B ratio 0.7 is higher than
  that with N/B ratio 4.0.
• At the same layer, sample with N/B ratio 0.7 has higher
  asphaltene content in solid than that with N/B ratio 4.0.
• Diluted bitumen with N/B ratio 0.7 has higher viscosity (4.84
  cP) than that (0.81 cP) with N/B ratio 4.0.
• Diluted bitumen with N/B ratio 0.7 has smaller density
  difference between oil and water (0.167 g/cm3) than that (0.227
  g/cm3) with N/B ratio 4.0.
• Based on Stokes’ Law, sedimentation rate of water and solid
  in diluted bitumen with N/B ratio 4.0 is 8.1 times faster than
  that with N/B ratio 0.7.
                     Conclusions
• Without solids, emulsion separation is almost complete
  with optimal demulsifier.
• Emulsion with N/B 0.7 is more stable than that with N/B
  4.0.
• Emulsion with N/B 4.0 adding 200 ppm PR5 has the lowest
  residual water and solid in oil.
• At the same layer, sample with N/B ratio 0.7 has higher
  asphaltene content in solid than that with N/B ratio 4.0.
• Clay solid has asphaltene content: in oil layer > in rag
  layer > at bottom layer.
• Based on Stokes’ Law, sedimentation rate of water and
  solid in diluted bitumen with N/B ratio 4.0 is 8.1 times
  faster than that with N/B ratio 0.7.
        Acknowledgement
• Syncrude Ltd.
• Consortium meeting

				
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