CA2469051A1 - Method of stabilising clay or shale - Google Patents
Method of stabilising clay or shale Download PDFInfo
- Publication number
- CA2469051A1 CA2469051A1 CA002469051A CA2469051A CA2469051A1 CA 2469051 A1 CA2469051 A1 CA 2469051A1 CA 002469051 A CA002469051 A CA 002469051A CA 2469051 A CA2469051 A CA 2469051A CA 2469051 A1 CA2469051 A1 CA 2469051A1
- Authority
- CA
- Canada
- Prior art keywords
- ions
- source
- ammonium
- group
- composition
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000004927 clay Substances 0.000 title claims abstract description 55
- 238000000034 method Methods 0.000 title claims abstract description 22
- 230000003019 stabilising effect Effects 0.000 title description 4
- 239000000203 mixture Substances 0.000 claims abstract description 86
- -1 borate ions Chemical class 0.000 claims abstract description 62
- 235000000346 sugar Nutrition 0.000 claims abstract description 27
- 239000008346 aqueous phase Substances 0.000 claims abstract description 18
- 229910001413 alkali metal ion Inorganic materials 0.000 claims abstract description 14
- 150000002500 ions Chemical class 0.000 claims abstract description 14
- 229910001420 alkaline earth metal ion Inorganic materials 0.000 claims abstract description 11
- 150000001720 carbohydrates Chemical group 0.000 claims abstract description 11
- 150000002772 monosaccharides Chemical class 0.000 claims abstract description 11
- 229920001542 oligosaccharide Polymers 0.000 claims abstract description 11
- 150000002482 oligosaccharides Chemical class 0.000 claims abstract description 11
- 230000008961 swelling Effects 0.000 claims abstract description 10
- 238000005553 drilling Methods 0.000 claims description 48
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims description 44
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 claims description 42
- 239000012530 fluid Substances 0.000 claims description 42
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 23
- 239000001103 potassium chloride Substances 0.000 claims description 21
- 235000011164 potassium chloride Nutrition 0.000 claims description 21
- 239000012141 concentrate Substances 0.000 claims description 19
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 15
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 claims description 13
- 150000003839 salts Chemical class 0.000 claims description 12
- 150000003863 ammonium salts Chemical class 0.000 claims description 9
- 230000015572 biosynthetic process Effects 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 239000002184 metal Substances 0.000 claims description 8
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 6
- 239000004327 boric acid Substances 0.000 claims description 6
- HUCVOHYBFXVBRW-UHFFFAOYSA-M caesium hydroxide Chemical compound [OH-].[Cs+] HUCVOHYBFXVBRW-UHFFFAOYSA-M 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 6
- 239000000654 additive Substances 0.000 claims description 5
- 229910052783 alkali metal Inorganic materials 0.000 claims description 5
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 4
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims description 4
- 239000000908 ammonium hydroxide Substances 0.000 claims description 4
- LYQFWZFBNBDLEO-UHFFFAOYSA-M caesium bromide Chemical compound [Br-].[Cs+] LYQFWZFBNBDLEO-UHFFFAOYSA-M 0.000 claims description 4
- AIYUHDOJVYHVIT-UHFFFAOYSA-M caesium chloride Chemical compound [Cl-].[Cs+] AIYUHDOJVYHVIT-UHFFFAOYSA-M 0.000 claims description 4
- 239000008103 glucose Substances 0.000 claims description 4
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 claims description 4
- 229910052792 caesium Inorganic materials 0.000 claims description 3
- RSCACTKJFSTWPV-UHFFFAOYSA-N disodium;3,7-dioxido-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonane;pentahydrate Chemical compound O.O.O.O.O.[Na+].[Na+].O1B([O-])OB2OB([O-])OB1O2 RSCACTKJFSTWPV-UHFFFAOYSA-N 0.000 claims description 3
- 235000010339 sodium tetraborate Nutrition 0.000 claims description 3
- OWEGMIWEEQEYGQ-UHFFFAOYSA-N 100676-05-9 Natural products OC1C(O)C(O)C(CO)OC1OCC1C(O)C(O)C(O)C(OC2C(OC(O)C(O)C2O)CO)O1 OWEGMIWEEQEYGQ-UHFFFAOYSA-N 0.000 claims description 2
- GUBGYTABKSRVRQ-XLOQQCSPSA-N Alpha-Lactose Chemical compound O[C@@H]1[C@@H](O)[C@@H](O)[C@@H](CO)O[C@H]1O[C@@H]1[C@@H](CO)O[C@H](O)[C@H](O)[C@H]1O GUBGYTABKSRVRQ-XLOQQCSPSA-N 0.000 claims description 2
- KOPBYBDAPCDYFK-UHFFFAOYSA-N Cs2O Inorganic materials [O-2].[Cs+].[Cs+] KOPBYBDAPCDYFK-UHFFFAOYSA-N 0.000 claims description 2
- RFSUNEUAIZKAJO-ARQDHWQXSA-N Fructose Chemical compound OC[C@H]1O[C@](O)(CO)[C@@H](O)[C@@H]1O RFSUNEUAIZKAJO-ARQDHWQXSA-N 0.000 claims description 2
- 229930091371 Fructose Natural products 0.000 claims description 2
- 239000005715 Fructose Substances 0.000 claims description 2
- GUBGYTABKSRVRQ-QKKXKWKRSA-N Lactose Natural products OC[C@H]1O[C@@H](O[C@H]2[C@H](O)[C@@H](O)C(O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@H]1O GUBGYTABKSRVRQ-QKKXKWKRSA-N 0.000 claims description 2
- GUBGYTABKSRVRQ-PICCSMPSSA-N Maltose Natural products O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@@H]1O[C@@H]1[C@@H](CO)OC(O)[C@H](O)[C@H]1O GUBGYTABKSRVRQ-PICCSMPSSA-N 0.000 claims description 2
- WUOZWCIWERXVLY-UHFFFAOYSA-N O.O.O.O.O.[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-] Chemical compound O.O.O.O.O.[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-] WUOZWCIWERXVLY-UHFFFAOYSA-N 0.000 claims description 2
- RJOIIWIZYCTTTH-UHFFFAOYSA-N O.O.O.O.[K+].[K+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] Chemical compound O.O.O.O.[K+].[K+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] RJOIIWIZYCTTTH-UHFFFAOYSA-N 0.000 claims description 2
- QUKZABJWJDFCMS-UHFFFAOYSA-N OB(O)O.OB(O)O.OB(O)O.OB(O)O.N.N.O.O.O.O Chemical compound OB(O)O.OB(O)O.OB(O)O.OB(O)O.N.N.O.O.O.O QUKZABJWJDFCMS-UHFFFAOYSA-N 0.000 claims description 2
- RRQBXRCWHNKYJY-UHFFFAOYSA-N OB(O)O.OB(O)O.OB(O)O.OB(O)O.OB(O)O.N.N.N.N.N.N.N.N.N.N.N.N.N.N.N.O.O.O.O Chemical compound OB(O)O.OB(O)O.OB(O)O.OB(O)O.OB(O)O.N.N.N.N.N.N.N.N.N.N.N.N.N.N.N.O.O.O.O RRQBXRCWHNKYJY-UHFFFAOYSA-N 0.000 claims description 2
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 claims description 2
- 229930006000 Sucrose Natural products 0.000 claims description 2
- SWLVFNYSXGMGBS-UHFFFAOYSA-N ammonium bromide Chemical compound [NH4+].[Br-] SWLVFNYSXGMGBS-UHFFFAOYSA-N 0.000 claims description 2
- 235000019270 ammonium chloride Nutrition 0.000 claims description 2
- GUBGYTABKSRVRQ-QUYVBRFLSA-N beta-maltose Chemical compound OC[C@H]1O[C@H](O[C@H]2[C@H](O)[C@@H](O)[C@H](O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@@H]1O GUBGYTABKSRVRQ-QUYVBRFLSA-N 0.000 claims description 2
- 229910021538 borax Inorganic materials 0.000 claims description 2
- IRDZMZNBKYCOKP-UHFFFAOYSA-N boric acid tetrahydrate Chemical compound O.O.O.O.B(O)(O)O.B(O)(O)O.B(O)(O)O.B(O)(O)O.B(O)(O)O IRDZMZNBKYCOKP-UHFFFAOYSA-N 0.000 claims description 2
- 150000001663 caesium Chemical class 0.000 claims description 2
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 claims description 2
- 238000004891 communication Methods 0.000 claims description 2
- YNPKJCSIKJCODK-UHFFFAOYSA-N disodium boric acid hydrogen borate decahydrate Chemical compound O.O.O.O.O.O.O.O.O.O.[Na+].[Na+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] YNPKJCSIKJCODK-UHFFFAOYSA-N 0.000 claims description 2
- RDMZIKMKSGCBKK-UHFFFAOYSA-N disodium;(9,11-dioxido-5-oxoboranyloxy-2,4,6,8,10,12,13-heptaoxa-1,3,5,7,9,11-hexaborabicyclo[5.5.1]tridecan-3-yl)oxy-oxoborane;tetrahydrate Chemical compound O.O.O.O.[Na+].[Na+].O1B(OB=O)OB(OB=O)OB2OB([O-])OB([O-])OB1O2 RDMZIKMKSGCBKK-UHFFFAOYSA-N 0.000 claims description 2
- AJFXNBUVIBKWBT-UHFFFAOYSA-N disodium;boric acid;hydrogen borate Chemical compound [Na+].[Na+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] AJFXNBUVIBKWBT-UHFFFAOYSA-N 0.000 claims description 2
- 239000008101 lactose Substances 0.000 claims description 2
- 239000000314 lubricant Substances 0.000 claims description 2
- VEOZPKWRJWCIJH-UHFFFAOYSA-N pentadecapotassium pentaborate tetrahydrate Chemical compound O.O.O.O.[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[K+].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-].[O-]B([O-])[O-] VEOZPKWRJWCIJH-UHFFFAOYSA-N 0.000 claims description 2
- JAKYJVJWXKRTSJ-UHFFFAOYSA-N sodium;oxido(oxo)borane;tetrahydrate Chemical compound O.O.O.O.[Na+].[O-]B=O JAKYJVJWXKRTSJ-UHFFFAOYSA-N 0.000 claims description 2
- 239000005720 sucrose Substances 0.000 claims description 2
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims 2
- 229910021537 Kernite Inorganic materials 0.000 claims 1
- SSXVEALMOOADMF-UHFFFAOYSA-N O.O.O.O.[Na+].[Na+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] Chemical compound O.O.O.O.[Na+].[Na+].OB(O)O.OB(O)O.OB(O)O.OB([O-])[O-] SSXVEALMOOADMF-UHFFFAOYSA-N 0.000 claims 1
- 239000003513 alkali Substances 0.000 claims 1
- NTBYNMBEYCCFPS-UHFFFAOYSA-N azane boric acid Chemical class N.N.N.OB(O)O NTBYNMBEYCCFPS-UHFFFAOYSA-N 0.000 claims 1
- UQGFMSUEHSUPRD-UHFFFAOYSA-N disodium;3,7-dioxido-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonane Chemical compound [Na+].[Na+].O1B([O-])OB2OB([O-])OB1O2 UQGFMSUEHSUPRD-UHFFFAOYSA-N 0.000 claims 1
- CDMADVZSLOHIFP-UHFFFAOYSA-N disodium;3,7-dioxido-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonane;decahydrate Chemical compound O.O.O.O.O.O.O.O.O.O.[Na+].[Na+].O1B([O-])OB2OB([O-])OB1O2 CDMADVZSLOHIFP-UHFFFAOYSA-N 0.000 claims 1
- 125000002791 glucosyl group Chemical group C1([C@H](O)[C@@H](O)[C@H](O)[C@H](O1)CO)* 0.000 claims 1
- 159000000001 potassium salts Chemical class 0.000 claims 1
- PKSSFLLYULKTIU-UHFFFAOYSA-N sodium oxido(oxo)borane dihydrate Chemical compound O.O.[Na+].[O-]B=O PKSSFLLYULKTIU-UHFFFAOYSA-N 0.000 claims 1
- 235000014347 soups Nutrition 0.000 claims 1
- WUUHFRRPHJEEKV-UHFFFAOYSA-N tripotassium borate Chemical class [K+].[K+].[K+].[O-]B([O-])[O-] WUUHFRRPHJEEKV-UHFFFAOYSA-N 0.000 claims 1
- BSVBQGMMJUBVOD-UHFFFAOYSA-N trisodium borate Chemical class [Na+].[Na+].[Na+].[O-]B([O-])[O-] BSVBQGMMJUBVOD-UHFFFAOYSA-N 0.000 claims 1
- 230000006641 stabilisation Effects 0.000 description 16
- 238000011105 stabilization Methods 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 15
- 235000008504 concentrate Nutrition 0.000 description 14
- 230000000717 retained effect Effects 0.000 description 14
- 238000012360 testing method Methods 0.000 description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 239000007788 liquid Substances 0.000 description 9
- 238000005755 formation reaction Methods 0.000 description 7
- 239000004615 ingredient Substances 0.000 description 7
- 229910021645 metal ion Inorganic materials 0.000 description 7
- 150000001642 boronic acid derivatives Chemical class 0.000 description 6
- 239000006185 dispersion Substances 0.000 description 6
- 150000002334 glycols Chemical class 0.000 description 6
- 239000003921 oil Substances 0.000 description 6
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 5
- 229920002472 Starch Polymers 0.000 description 5
- 238000005520 cutting process Methods 0.000 description 5
- LYCAIKOWRPUZTN-UHFFFAOYSA-N ethylene glycol Natural products OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 5
- 150000004760 silicates Chemical class 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 230000000087 stabilizing effect Effects 0.000 description 5
- 239000008107 starch Substances 0.000 description 5
- 235000019698 starch Nutrition 0.000 description 5
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 4
- 230000001687 destabilization Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000006188 syrup Substances 0.000 description 4
- 235000020357 syrup Nutrition 0.000 description 4
- 239000008399 tap water Substances 0.000 description 4
- 235000020679 tap water Nutrition 0.000 description 4
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 3
- 101100348017 Drosophila melanogaster Nazo gene Proteins 0.000 description 3
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 3
- 229940063013 borate ion Drugs 0.000 description 3
- 239000001110 calcium chloride Substances 0.000 description 3
- 229910001628 calcium chloride Inorganic materials 0.000 description 3
- 235000011148 calcium chloride Nutrition 0.000 description 3
- 239000001913 cellulose Substances 0.000 description 3
- 229920002678 cellulose Polymers 0.000 description 3
- 238000010790 dilution Methods 0.000 description 3
- 239000012895 dilution Substances 0.000 description 3
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 3
- 230000003204 osmotic effect Effects 0.000 description 3
- 239000003208 petroleum Substances 0.000 description 3
- 239000000230 xanthan gum Substances 0.000 description 3
- 229920001285 xanthan gum Polymers 0.000 description 3
- 235000010493 xanthan gum Nutrition 0.000 description 3
- 229940082509 xanthan gum Drugs 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- 235000015076 Shorea robusta Nutrition 0.000 description 2
- 244000166071 Shorea robusta Species 0.000 description 2
- 230000032683 aging Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 2
- 229910052601 baryte Inorganic materials 0.000 description 2
- 239000010428 baryte Substances 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 239000003112 inhibitor Substances 0.000 description 2
- 229910001629 magnesium chloride Inorganic materials 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 229920001515 polyalkylene glycol Polymers 0.000 description 2
- 229920001223 polyethylene glycol Polymers 0.000 description 2
- 229920005862 polyol Polymers 0.000 description 2
- 150000003077 polyols Chemical class 0.000 description 2
- 229920001451 polypropylene glycol Polymers 0.000 description 2
- 229910001414 potassium ion Inorganic materials 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- WYXIGTJNYDDFFH-UHFFFAOYSA-Q triazanium;borate Chemical compound [NH4+].[NH4+].[NH4+].[O-]B([O-])[O-] WYXIGTJNYDDFFH-UHFFFAOYSA-Q 0.000 description 2
- QFSNCROGCLRZHC-UHFFFAOYSA-N 2,3-dihydroxypropoxyboronic acid Chemical class OCC(O)COB(O)O QFSNCROGCLRZHC-UHFFFAOYSA-N 0.000 description 1
- 235000016068 Berberis vulgaris Nutrition 0.000 description 1
- 241000335053 Beta vulgaris Species 0.000 description 1
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000014755 Eruca sativa Nutrition 0.000 description 1
- 244000024675 Eruca sativa Species 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 229920000881 Modified starch Polymers 0.000 description 1
- 239000004368 Modified starch Substances 0.000 description 1
- XQCFHQBGMWUEMY-ZPUQHVIOSA-N Nitrovin Chemical compound C=1C=C([N+]([O-])=O)OC=1\C=C\C(=NNC(=N)N)\C=C\C1=CC=C([N+]([O-])=O)O1 XQCFHQBGMWUEMY-ZPUQHVIOSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 239000004111 Potassium silicate Substances 0.000 description 1
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical class CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 150000001398 aluminium Chemical class 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 229920005551 calcium lignosulfonate Polymers 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 150000002016 disaccharides Chemical class 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000013505 freshwater Substances 0.000 description 1
- 229910052949 galena Inorganic materials 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052595 hematite Inorganic materials 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 229910052900 illite Inorganic materials 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 230000009545 invasion Effects 0.000 description 1
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 1
- XCAUINMIESBTBL-UHFFFAOYSA-N lead(ii) sulfide Chemical compound [Pb]=S XCAUINMIESBTBL-UHFFFAOYSA-N 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000019426 modified starch Nutrition 0.000 description 1
- 235000013379 molasses Nutrition 0.000 description 1
- VGIBGUSAECPPNB-UHFFFAOYSA-L nonaaluminum;magnesium;tripotassium;1,3-dioxido-2,4,5-trioxa-1,3-disilabicyclo[1.1.1]pentane;iron(2+);oxygen(2-);fluoride;hydroxide Chemical compound [OH-].[O-2].[O-2].[O-2].[O-2].[O-2].[F-].[Mg+2].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[K+].[K+].[K+].[Fe+2].O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2 VGIBGUSAECPPNB-UHFFFAOYSA-L 0.000 description 1
- 239000006174 pH buffer Substances 0.000 description 1
- 230000036961 partial effect Effects 0.000 description 1
- 239000006187 pill Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000002798 polar solvent Substances 0.000 description 1
- 229920002401 polyacrylamide Polymers 0.000 description 1
- 229920000223 polyglycerol Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- XAEFZNCEHLXOMS-UHFFFAOYSA-M potassium benzoate Chemical group [K+].[O-]C(=O)C1=CC=CC=C1 XAEFZNCEHLXOMS-UHFFFAOYSA-M 0.000 description 1
- NNHHDJVEYQHLHG-UHFFFAOYSA-N potassium silicate Chemical compound [K+].[K+].[O-][Si]([O-])=O NNHHDJVEYQHLHG-UHFFFAOYSA-N 0.000 description 1
- 229910052913 potassium silicate Inorganic materials 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 235000013772 propylene glycol Nutrition 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- NVIFVTYDZMXWGX-UHFFFAOYSA-N sodium metaborate Chemical compound [Na+].[O-]B=O NVIFVTYDZMXWGX-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 150000008163 sugars Chemical class 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 229920003169 water-soluble polymer Polymers 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices, or the like
- E21B33/138—Plastering the borehole wall; Injecting into the formation
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/02—Well-drilling compositions
- C09K8/04—Aqueous well-drilling compositions
- C09K8/14—Clay-containing compositions
- C09K8/16—Clay-containing compositions characterised by the inorganic compounds other than clay
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/02—Well-drilling compositions
- C09K8/04—Aqueous well-drilling compositions
- C09K8/14—Clay-containing compositions
- C09K8/18—Clay-containing compositions characterised by the organic compounds
- C09K8/20—Natural organic compounds or derivatives thereof, e.g. polysaccharides or lignin derivatives
- C09K8/206—Derivatives of other natural products, e.g. cellulose, starch, sugars
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/5045—Compositions based on water or polar solvents containing inorganic compounds
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/506—Compositions based on water or polar solvents containing organic compounds
- C09K8/508—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/514—Compositions based on water or polar solvents containing organic compounds macromolecular compounds of natural origin, e.g. polysaccharides, cellulose
Abstract
A method of reducing the swelling of shale or clay encountered in a wellbore, the method comprising introducing into the wellbore a composition comprising:
(a) a continuous aqueous phase; (b) a source of borate ions; (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions; and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
(a) a continuous aqueous phase; (b) a source of borate ions; (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions; and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
Description
METHOD OF STABILISING CLAY OR SHALE
The present invention relates to a composition useful for stabilizing a clayey or shaley formation surrounding a wellbore. In particular, the present invention relates to a clay. or shale swelling inhibitor composition for use during drilling, completing or maintaining wellbores.
Drilling fluids are used in the drilling of oil and gas wells. In rotary drilling operations drilling fluids are pumped down from the surface through a drill string to a drill bit. They emerge through ports in the drill bit and return to the surface via an annular space located between the drill string and the walls of the borehole.
The functions of drilling fluids may be multiple: for example, they serve to cool and lubricate both the drill bit and drill string, they transport drill cuttings to the surface, they equalize the pressure between the fluids in the wellbore and the formation fluids, they prevent "squeezing" of the wellbore or caving of the formation into the wellbore, or minimise any potential damage to the "pay zone" of the wellbore.
Drilling fluids are of two basic types, oil-based (hereinafter referred to as OBMs 1 S - oil based muds), and water-based (hereinafter referred to as WBMs -water based muds). OBMs are superior in performance to WBMs in several important respects including lubricating properties and thermal stability thereby allowing wells to be drilled at a faster rate than when using WBMs resulting in considerable cost savings. In particular, OBMs are useful where the downhole temperature is high, for example when drilling deviated wells through high temperature formations. Furthermore, OBMs mitigate problems associated with swelling and dispersion of clays or shales, which are frequently encountered during drilling with WBMs. Such problems will hereinafter be referred to as "clay or shale destabilization".
Unfortunately, OBMs are less attractive than WBMs from an environmental perspective. The disposal of spent OBMs, and the associated problems of cuttings clean-up and disposal are posing increasing difficulties for the oil and gas exploration industry. One proposal has been the use of biodegradable oils to formulate OBMs, but such products may not comply with future legislation which is expected to impose more stringent limits on disposal of waste materials. The consequence of this is that much effort has been expended in the development of WBMs having improved performance in terms of reducing clay or shale destabilization. If no attempts are made to inhibit hydration and swelling of clays or shales the consequences can be severe.
Thus, clay or shale destabilization may result in weaknesses developing in the formation, possibly leading to erosion of the borehole. Also, as would be well known to the person skilled in the art, the phenomenon of "stuck pipe" can occur, and furthermore, logging operations during drilling can be hampered.
A number of approaches have been proposed for reducing the clay or shale destabilization characteristics of WBMs. The use of salts such as Group IA
metal salts, in particular, potassium chloride, to balance the water activity between the clay or shale and the drilling fluid, or even to provide an osmotic gradient that leads to a net flow of water out of the clay or shale, has been employed to prevent clay or shale hydration.
This approach may be combined with the use of silicates which are capable of forming osmotic membranes on the exposed surface of the clay or shale, as described, for example, in US 3640343, and van Oort et. al. in SPE/IADC paper No. 35059, presented at the IADC/SPE Drilling Conf. New Orleans, 12-15'h March 1996. The osmotic membrane facilitates the flow of water out of the clay or shale whilst inhibiting the diffusion of ions between the clay or shale and the fluids in the wellbore thereby improving the clay or shale stabilization characteristics of the WBM.
The precipitation of silicates on the exposed surface of the clay or shale is also believed to produce a physical barrier against invasion of fluids from the wellbore into the clay or shale. The use of silicates, however, may be associated with problems of high drilling torques and poor lubricity owing to the tendency of silicates to precipitate out on metal surfaces, for example, on the drill bit. Also, the use of silicates may lead to problems of incompatibility with conventional drilling fluid additives.
Finally, silicate
The present invention relates to a composition useful for stabilizing a clayey or shaley formation surrounding a wellbore. In particular, the present invention relates to a clay. or shale swelling inhibitor composition for use during drilling, completing or maintaining wellbores.
Drilling fluids are used in the drilling of oil and gas wells. In rotary drilling operations drilling fluids are pumped down from the surface through a drill string to a drill bit. They emerge through ports in the drill bit and return to the surface via an annular space located between the drill string and the walls of the borehole.
The functions of drilling fluids may be multiple: for example, they serve to cool and lubricate both the drill bit and drill string, they transport drill cuttings to the surface, they equalize the pressure between the fluids in the wellbore and the formation fluids, they prevent "squeezing" of the wellbore or caving of the formation into the wellbore, or minimise any potential damage to the "pay zone" of the wellbore.
Drilling fluids are of two basic types, oil-based (hereinafter referred to as OBMs 1 S - oil based muds), and water-based (hereinafter referred to as WBMs -water based muds). OBMs are superior in performance to WBMs in several important respects including lubricating properties and thermal stability thereby allowing wells to be drilled at a faster rate than when using WBMs resulting in considerable cost savings. In particular, OBMs are useful where the downhole temperature is high, for example when drilling deviated wells through high temperature formations. Furthermore, OBMs mitigate problems associated with swelling and dispersion of clays or shales, which are frequently encountered during drilling with WBMs. Such problems will hereinafter be referred to as "clay or shale destabilization".
Unfortunately, OBMs are less attractive than WBMs from an environmental perspective. The disposal of spent OBMs, and the associated problems of cuttings clean-up and disposal are posing increasing difficulties for the oil and gas exploration industry. One proposal has been the use of biodegradable oils to formulate OBMs, but such products may not comply with future legislation which is expected to impose more stringent limits on disposal of waste materials. The consequence of this is that much effort has been expended in the development of WBMs having improved performance in terms of reducing clay or shale destabilization. If no attempts are made to inhibit hydration and swelling of clays or shales the consequences can be severe.
Thus, clay or shale destabilization may result in weaknesses developing in the formation, possibly leading to erosion of the borehole. Also, as would be well known to the person skilled in the art, the phenomenon of "stuck pipe" can occur, and furthermore, logging operations during drilling can be hampered.
A number of approaches have been proposed for reducing the clay or shale destabilization characteristics of WBMs. The use of salts such as Group IA
metal salts, in particular, potassium chloride, to balance the water activity between the clay or shale and the drilling fluid, or even to provide an osmotic gradient that leads to a net flow of water out of the clay or shale, has been employed to prevent clay or shale hydration.
This approach may be combined with the use of silicates which are capable of forming osmotic membranes on the exposed surface of the clay or shale, as described, for example, in US 3640343, and van Oort et. al. in SPE/IADC paper No. 35059, presented at the IADC/SPE Drilling Conf. New Orleans, 12-15'h March 1996. The osmotic membrane facilitates the flow of water out of the clay or shale whilst inhibiting the diffusion of ions between the clay or shale and the fluids in the wellbore thereby improving the clay or shale stabilization characteristics of the WBM.
The precipitation of silicates on the exposed surface of the clay or shale is also believed to produce a physical barrier against invasion of fluids from the wellbore into the clay or shale. The use of silicates, however, may be associated with problems of high drilling torques and poor lubricity owing to the tendency of silicates to precipitate out on metal surfaces, for example, on the drill bit. Also, the use of silicates may lead to problems of incompatibility with conventional drilling fluid additives.
Finally, silicate
2
3 PCT/GB02/05635 solutions are highly alkaline and this can lead to difficulties with safe storage and handling.
Other proposals for improving the clay or shale stabilization performance of WBMs include the addition of glycols or polyols. Suitable glycols or polyols include, for example, polyglycerols, glycols, polyalkylene glycols (PAG), e.g., polyethylene glycols (PEG), polypropylene glycols (PPG) and copolymers of ethylene and propylene glycols, alcohol ethoxylates and glycol ethers as described in for example, EP
0495579, US 4830765, US 4172800 and The Society of Petroleum Engineers Reports SPE
and 28818. In The Society of Petroleum Engineers Report SPE 28960 it is disclosed that potassium ions work synergistically with glycols in drilling fluids to improve the shale stabilization performance of the WBMs.
Other proposals described in the art to improve the clay or shale stabilization properties of WBMs include the use of additives such as aluminium complexes, chemically modified starch, chemically modified cellulosic materials, water soluble 1 S polyacrylamides and other water soluble polymers, lime or gypsum, asphaltene derived products and calcium lignosulphonates.
The use of borates in hydraulic fracturing fluids is described in US 5372732, US
5445223, GB 2253868 and WO 87/00236 while US 5220960 discloses the use of borates as cement retardants for completion operations.
CA 1248337 teaches the use of borates in the field for low specific gravity non-damaging workover and completion fluids. CA 1303841 describes the use of borates in water profile control in oil recovery. E L Bigelow in The Society of Petroleum Engineers publication SPE 27644 discloses that borates may be used in pulsed neutron logging. Borates have also been used in lost circulation treatments (fluid loss pills) during drilling operations (as described in US 5372732).
US 6105691 refers to the use of boric acid or glycerol-borate esters in drilling fluids for the purposes of improving the lubricity of the drilling fluid and its clay dispersion characteristics. However, US 6105691 is silent concerning any beneficial effect of borate on the clay or shale stabilizing properties of drilling fluids.
RU 1699991 relates to a silicate drilling mud having increased mud stability and calcium chloride resistance. The drilling mud is prepared by adding boric acid and sodium or potassium silicate to water to produce a gel-like mass, which is then diluted until the required viscosity, structural and mechanical properties have been obtained.
An organic stabilizer may then be added to adjust filtration. There is no suggestion that a sugar may be added to the mud to increase its shale or clay stabilization characteristics.
S An object of the present invention is to provide an aqueous based composition, in particular, an aqueous based drilling fluid composition, having improved clay or shale stabilization characteristics. A further object of the present invention is to provide a method of reducing the swelling of shale or clay encountered in a wellbore, for example, during drilling through a formation.
It has now been found that an aqueous based composition which contains a combination of (a) borate ions and (b) ions selected from the group consisting of alkaline earth) metal ions and ammonium ions exhibits markedly improved clay or shale stabilization properties compared with aqueous based compositions containing components (a) or (b) alone. It has also been found that the addition of a silicate to the aqueous based composition containing components (a) and (b) has a detrimental effect on its clay or shale stabilization properties. It has further been found that the addition of at least one sugar, selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups, to the aqueous based composition containing components (a) and (b) improves the clay or shale stabilization characteristics thereof.
Thus, in a first embodiment of the present invention there is provided a use of a combination of (a) a source of borate ions, (b) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions and (c) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups, in a composition comprising a continuous aqueous phase, to improve the clay or shale stabilizing properties thereof.
In a second embodiment of the present invention there is provided a method of reducing the swelling of shale or clay encountered in a wellbore, the method comprising introducing into the wellbore a composition comprising:
(a) a continuous aqueous phase;
(b) a source of borate ions;
Other proposals for improving the clay or shale stabilization performance of WBMs include the addition of glycols or polyols. Suitable glycols or polyols include, for example, polyglycerols, glycols, polyalkylene glycols (PAG), e.g., polyethylene glycols (PEG), polypropylene glycols (PPG) and copolymers of ethylene and propylene glycols, alcohol ethoxylates and glycol ethers as described in for example, EP
0495579, US 4830765, US 4172800 and The Society of Petroleum Engineers Reports SPE
and 28818. In The Society of Petroleum Engineers Report SPE 28960 it is disclosed that potassium ions work synergistically with glycols in drilling fluids to improve the shale stabilization performance of the WBMs.
Other proposals described in the art to improve the clay or shale stabilization properties of WBMs include the use of additives such as aluminium complexes, chemically modified starch, chemically modified cellulosic materials, water soluble 1 S polyacrylamides and other water soluble polymers, lime or gypsum, asphaltene derived products and calcium lignosulphonates.
The use of borates in hydraulic fracturing fluids is described in US 5372732, US
5445223, GB 2253868 and WO 87/00236 while US 5220960 discloses the use of borates as cement retardants for completion operations.
CA 1248337 teaches the use of borates in the field for low specific gravity non-damaging workover and completion fluids. CA 1303841 describes the use of borates in water profile control in oil recovery. E L Bigelow in The Society of Petroleum Engineers publication SPE 27644 discloses that borates may be used in pulsed neutron logging. Borates have also been used in lost circulation treatments (fluid loss pills) during drilling operations (as described in US 5372732).
US 6105691 refers to the use of boric acid or glycerol-borate esters in drilling fluids for the purposes of improving the lubricity of the drilling fluid and its clay dispersion characteristics. However, US 6105691 is silent concerning any beneficial effect of borate on the clay or shale stabilizing properties of drilling fluids.
RU 1699991 relates to a silicate drilling mud having increased mud stability and calcium chloride resistance. The drilling mud is prepared by adding boric acid and sodium or potassium silicate to water to produce a gel-like mass, which is then diluted until the required viscosity, structural and mechanical properties have been obtained.
An organic stabilizer may then be added to adjust filtration. There is no suggestion that a sugar may be added to the mud to increase its shale or clay stabilization characteristics.
S An object of the present invention is to provide an aqueous based composition, in particular, an aqueous based drilling fluid composition, having improved clay or shale stabilization characteristics. A further object of the present invention is to provide a method of reducing the swelling of shale or clay encountered in a wellbore, for example, during drilling through a formation.
It has now been found that an aqueous based composition which contains a combination of (a) borate ions and (b) ions selected from the group consisting of alkaline earth) metal ions and ammonium ions exhibits markedly improved clay or shale stabilization properties compared with aqueous based compositions containing components (a) or (b) alone. It has also been found that the addition of a silicate to the aqueous based composition containing components (a) and (b) has a detrimental effect on its clay or shale stabilization properties. It has further been found that the addition of at least one sugar, selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups, to the aqueous based composition containing components (a) and (b) improves the clay or shale stabilization characteristics thereof.
Thus, in a first embodiment of the present invention there is provided a use of a combination of (a) a source of borate ions, (b) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions and (c) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups, in a composition comprising a continuous aqueous phase, to improve the clay or shale stabilizing properties thereof.
In a second embodiment of the present invention there is provided a method of reducing the swelling of shale or clay encountered in a wellbore, the method comprising introducing into the wellbore a composition comprising:
(a) a continuous aqueous phase;
(b) a source of borate ions;
4 (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions; and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
S The composition that is introduced into the wellbore may be used in drilling, completing or maintaining a wellbore. Where the composition is used in drilling a wellbore, the composition is preferably circulated in the wellbore thereby stabilising the clay or shale.
According to a preferred aspect of the present invention there is provided a method of reducing the swelling of shale or clay encountered during the drilling of a wellbore through a formation using a drill string disposed within the wellbore, said drill string having a first end and a second end, the first end of the drill string being located at or near the surface of the wellbore and the second end of the drill string being in communication with a drill bit having ports therein, wherein:
(A) a drilling fluid composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions, and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups is introduced into the first end of the drill string, is pumped through the drill string from the first end to the second end thereof and is discharged into the wellbore through the ports in the drill bit; and (B) the drilling fluid composition is recycled to the first end of the drill string via an annular space which is provided between the drill string and the walls of the wellbore.
Suitably, the continuous aqueous phase of the composition may be fresh water, tap water, sea water, river water or aquifer water.
Preferably, the source of borate ions is an alkali metal borate, an ammonium borate or mixtures thereof. Preferably, the source of the borate ions is a borate of generic formula (I):
n(M120)m(B203).xH20 (I) wherein M' represents an alkali metal (preferably, sodium or potassium) or NH4, n is an integer in the range 0 to 5, m is an integer in the range 1 to 7, the ratio of n:m is 0 - 1:1 and x is an integer in the range 0 to 10. Regardless of the source of borate ions, it is
S The composition that is introduced into the wellbore may be used in drilling, completing or maintaining a wellbore. Where the composition is used in drilling a wellbore, the composition is preferably circulated in the wellbore thereby stabilising the clay or shale.
According to a preferred aspect of the present invention there is provided a method of reducing the swelling of shale or clay encountered during the drilling of a wellbore through a formation using a drill string disposed within the wellbore, said drill string having a first end and a second end, the first end of the drill string being located at or near the surface of the wellbore and the second end of the drill string being in communication with a drill bit having ports therein, wherein:
(A) a drilling fluid composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions, and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups is introduced into the first end of the drill string, is pumped through the drill string from the first end to the second end thereof and is discharged into the wellbore through the ports in the drill bit; and (B) the drilling fluid composition is recycled to the first end of the drill string via an annular space which is provided between the drill string and the walls of the wellbore.
Suitably, the continuous aqueous phase of the composition may be fresh water, tap water, sea water, river water or aquifer water.
Preferably, the source of borate ions is an alkali metal borate, an ammonium borate or mixtures thereof. Preferably, the source of the borate ions is a borate of generic formula (I):
n(M120)m(B203).xH20 (I) wherein M' represents an alkali metal (preferably, sodium or potassium) or NH4, n is an integer in the range 0 to 5, m is an integer in the range 1 to 7, the ratio of n:m is 0 - 1:1 and x is an integer in the range 0 to 10. Regardless of the source of borate ions, it is
5 preferred that the ratio of n:m in the composition is in the range 0.1:1 to 1.2:1. This ratio may be adjusted by addition of an alkali metal hydroxide (for example, sodium hydroxide or potassium hydroxide) or ammonium hydroxide to the composition.
The source of borate ions may be a refined product or a natural mineral.
S Preferably, the source of borate ions may be selected from, but not limited to, the group consisting of disodium tetraborate pentahydrate (Na20'2B203'SH20), disodium tetraborate decahydrate or tincal (NaZO'2BZO3' 1 OHZO), disodium tetraborate (Na20~2Bz03), sodium metaborate tetrahydrate (Na20'B203'8H20), sodium metaborate dehydrate (Na20'B203'4H20), sodium pentaborate pentahydrate (Na20'SB203'1OH20), disodium octaborate tetrahydrate (NazO'4B203'4Hz0), boric acid (H3B03), dipotassium tetraborate tetrahydrate (Kz0'2BZ03~4Hz0), potassium pentaborate tetrahydrate (K20'SBz03'8H20), diammonium tetraborate tetrahydrate ((NH4)20'2Bz03'4H20), ammonium pentaborate tetrahydrate ((NH4)20'SB203'8H20) and caesium pentaborate tetrahydrate (Cs20'SB203'8H20).
Where the source of borate ions is an alkali metal borate or an ammonium borate, the borate will also act as a source of alkali metal ions or of ammonium ions respectively. If necessary, a source of additional alkali metal ions or ammonium ions may be added to the composition, as described above.
The amount of borate, expressed as B203 in lb/bbl (pounds per barrel) present in the continuous aqueous phase of the composition is preferably in the range 0.1 to 150 lb/bbl, and more preferably, in the range 0.5 to 50 lb/bbl. , It is envisaged that the source of borate ions may be sold as a concentrate ready for dilution with the composition. The concentrate may comprise a solution or .
dispersion of a borate in an aqueous liquid or a non aqueous liquid. Suitable aqueous liquids are as described above. Suitable non aqueous liquids include polar solvents such as alcohols and glycols. Preferably, the concentrate comprises a solution or dispersion of a borate in an aqueous liquid. The amount of borate, expressed as B203 in lb/bbl (pounds per barrel) present in the concentrate is preferably in the range 10 to 250 lb/bbl.
Suitably, the source of the ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions is a water soluble salt of an alkaline earth) metal, a water soluble ammonium salt or mixtures thereof. It is preferred that the water soluble salt of the alkaline earth) metal is not a silicate. Preferably the water
The source of borate ions may be a refined product or a natural mineral.
S Preferably, the source of borate ions may be selected from, but not limited to, the group consisting of disodium tetraborate pentahydrate (Na20'2B203'SH20), disodium tetraborate decahydrate or tincal (NaZO'2BZO3' 1 OHZO), disodium tetraborate (Na20~2Bz03), sodium metaborate tetrahydrate (Na20'B203'8H20), sodium metaborate dehydrate (Na20'B203'4H20), sodium pentaborate pentahydrate (Na20'SB203'1OH20), disodium octaborate tetrahydrate (NazO'4B203'4Hz0), boric acid (H3B03), dipotassium tetraborate tetrahydrate (Kz0'2BZ03~4Hz0), potassium pentaborate tetrahydrate (K20'SBz03'8H20), diammonium tetraborate tetrahydrate ((NH4)20'2Bz03'4H20), ammonium pentaborate tetrahydrate ((NH4)20'SB203'8H20) and caesium pentaborate tetrahydrate (Cs20'SB203'8H20).
Where the source of borate ions is an alkali metal borate or an ammonium borate, the borate will also act as a source of alkali metal ions or of ammonium ions respectively. If necessary, a source of additional alkali metal ions or ammonium ions may be added to the composition, as described above.
The amount of borate, expressed as B203 in lb/bbl (pounds per barrel) present in the continuous aqueous phase of the composition is preferably in the range 0.1 to 150 lb/bbl, and more preferably, in the range 0.5 to 50 lb/bbl. , It is envisaged that the source of borate ions may be sold as a concentrate ready for dilution with the composition. The concentrate may comprise a solution or .
dispersion of a borate in an aqueous liquid or a non aqueous liquid. Suitable aqueous liquids are as described above. Suitable non aqueous liquids include polar solvents such as alcohols and glycols. Preferably, the concentrate comprises a solution or dispersion of a borate in an aqueous liquid. The amount of borate, expressed as B203 in lb/bbl (pounds per barrel) present in the concentrate is preferably in the range 10 to 250 lb/bbl.
Suitably, the source of the ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions is a water soluble salt of an alkaline earth) metal, a water soluble ammonium salt or mixtures thereof. It is preferred that the water soluble salt of the alkaline earth) metal is not a silicate. Preferably the water
6 soluble salt is a potassium salt, caesium salt or ammonium salt including, but not limited to, potassium bromide, caesium bromide, ammonium bromide, potassium chloride, caesium chloride, ammonium chloride, potassium hydroxide,.caesium hydroxide and ammonium hydroxide. For example, if boric acid is used as the source of borate, then the water soluble salt is preferably selected from potassium hydroxide, caesium hydroxide and ammonium hydroxide.
Suitably, the alkaline earth) metal salt, ammonium salt or mixtures thereof may be present in the continuous aqueous phase of the composition in an amount in the range 0.1 to 150 lb/bbl, preferably, in the range 0.5 to 100 lb/bbl.
It is envisaged that the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof may be sold as a concentrate ready for dilution with the composition. Preferably, the concentrate may comprise a solution or dispersion of an alkaline earth) metal salt, ammonium salt or mixtures thereof in an aqueous liquid.
Preferably, the concentration of alkaline earth) metal salt, ammonium salt or mixtures thereof in the concentrate is in the range 10 to 1 SO lb/bbl, preferably 10 to 100 lb/bbl.
The sugar may be selected from the group consisting of monosaccharides, and oligosaccharides having 2 to 4 saccharide groups. Preferred monosaccharides include glucose and fructose. Preferred disaccharides include sucrose (for example, obtained from cane or beet), maltose and lactose. It is also envisaged that the source of the sugar may be a mixture of sugars, for example, glucose syrup, golden syrup, molasses or Activ 7 TT'' (a water soluble liquid syrup obtained by partial hydrolysis of starch).
Suitably, the amount of sugar in the continuous aqueous phase of the composition is in the range from 0.1 to 150 Ib/bbl, preferably 0.5 to 50 lb/bbl.
It is envisaged that the source of the sugar may be sold as a concentrate ready for , dilution with the composition. Preferably, the concentrate may comprise a solution or dispersion of the sugar in an aqueous liquid. Preferably, the concentration of the sugar in the concentrate is in the range 10 to 300 lb/bbl, preferably 20 to 300 lb/bbl.
It is also envisaged that (a) the source of borate ions, (b) the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof and (c) the source of sugar may be sold as a mixed concentrate. Suitably, the amount of components (a), (b) and (c) in the mixed concentrate are as described above for the individual concentrates.
An advantage of the present invention is that the composition is stable at
Suitably, the alkaline earth) metal salt, ammonium salt or mixtures thereof may be present in the continuous aqueous phase of the composition in an amount in the range 0.1 to 150 lb/bbl, preferably, in the range 0.5 to 100 lb/bbl.
It is envisaged that the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof may be sold as a concentrate ready for dilution with the composition. Preferably, the concentrate may comprise a solution or dispersion of an alkaline earth) metal salt, ammonium salt or mixtures thereof in an aqueous liquid.
Preferably, the concentration of alkaline earth) metal salt, ammonium salt or mixtures thereof in the concentrate is in the range 10 to 1 SO lb/bbl, preferably 10 to 100 lb/bbl.
The sugar may be selected from the group consisting of monosaccharides, and oligosaccharides having 2 to 4 saccharide groups. Preferred monosaccharides include glucose and fructose. Preferred disaccharides include sucrose (for example, obtained from cane or beet), maltose and lactose. It is also envisaged that the source of the sugar may be a mixture of sugars, for example, glucose syrup, golden syrup, molasses or Activ 7 TT'' (a water soluble liquid syrup obtained by partial hydrolysis of starch).
Suitably, the amount of sugar in the continuous aqueous phase of the composition is in the range from 0.1 to 150 Ib/bbl, preferably 0.5 to 50 lb/bbl.
It is envisaged that the source of the sugar may be sold as a concentrate ready for , dilution with the composition. Preferably, the concentrate may comprise a solution or dispersion of the sugar in an aqueous liquid. Preferably, the concentration of the sugar in the concentrate is in the range 10 to 300 lb/bbl, preferably 20 to 300 lb/bbl.
It is also envisaged that (a) the source of borate ions, (b) the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof and (c) the source of sugar may be sold as a mixed concentrate. Suitably, the amount of components (a), (b) and (c) in the mixed concentrate are as described above for the individual concentrates.
An advantage of the present invention is that the composition is stable at
7 elevated temperature for a prolonged period of time. Typically, the composition is stable for a period of at least 12 hours, preferably at least 16 hours at a temperature of at least 100°C, preferably at least 120°C.
A further advantage of the present invention is that the source of borate ions acts as a pH buffer for the composition thereby controlling the pH at a value which is typically above 8, preferably above 9. Accordingly, there is no requirement to include a pH control agent such as sodium hydroxide or potassium hydroxide.
The composition may be beneficially used in combination with conventional additives for improving the clay or shale stabilization properties of a drilling or completion fluid. These conventional additives include, but are not limited to glycols.
The composition may also contain additional ingredients such as weighting agents, e.g., barite, haematite, or galena; viscosifiers, e.g. xanthan gum;
fluid loss control agents, e.g., starch or cellulose derivatives (e.g., carboxymethyl cellulose);
defoamers and lubricants.
Yet a further advantage of the composition is that it is compatible with conventional fluid loss control agents.
There is no special requirement in relation to the preparation of the composition.
The source of borate ions, the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof, and optionally the source of the sugar may be added in any order to the continuous aqueous phase (either as concentrates or as solids). Gentle heating is optional to dissolve or disperse the source of borate ions, the source of alkaline earth) metal ions, ammonium ions or mixtures thereof, and the optional source of the sugar in the continuous aqueous phase of the composition.
As discussed above, the sugar has been found to improve the clay or shale stabilization properties of the aqueous based composition used in the present invention.
Thus, in yet a further embodiment of the present invention there is provided a composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions and (d) a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
The components (a) to (d) of the composition of the present invention have the
A further advantage of the present invention is that the source of borate ions acts as a pH buffer for the composition thereby controlling the pH at a value which is typically above 8, preferably above 9. Accordingly, there is no requirement to include a pH control agent such as sodium hydroxide or potassium hydroxide.
The composition may be beneficially used in combination with conventional additives for improving the clay or shale stabilization properties of a drilling or completion fluid. These conventional additives include, but are not limited to glycols.
The composition may also contain additional ingredients such as weighting agents, e.g., barite, haematite, or galena; viscosifiers, e.g. xanthan gum;
fluid loss control agents, e.g., starch or cellulose derivatives (e.g., carboxymethyl cellulose);
defoamers and lubricants.
Yet a further advantage of the composition is that it is compatible with conventional fluid loss control agents.
There is no special requirement in relation to the preparation of the composition.
The source of borate ions, the source of the alkaline earth) metal ions, ammonium ions or mixtures thereof, and optionally the source of the sugar may be added in any order to the continuous aqueous phase (either as concentrates or as solids). Gentle heating is optional to dissolve or disperse the source of borate ions, the source of alkaline earth) metal ions, ammonium ions or mixtures thereof, and the optional source of the sugar in the continuous aqueous phase of the composition.
As discussed above, the sugar has been found to improve the clay or shale stabilization properties of the aqueous based composition used in the present invention.
Thus, in yet a further embodiment of the present invention there is provided a composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions and (d) a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
The components (a) to (d) of the composition of the present invention have the
8 preferred features described above.
The performance of the composition of the present invention in clay or shale stabilization is now illustrated by reference to the following examples. .
Example 1 Aqueous based compositions, were prepared comprising the components shown in Table 1. Each composition was made up to a weight of 80g with demineralised water and was contained in a 100m1 glass bottle.
A model shale (London Clay; l Og) screened to a particle size range of 2-4 mm, was added to each bottle. The bottles were then sealed with screw caps and rolled at 20rpm for 16 hours (bottle rolling test). Each sample mixture was then passed through a separate pre-weighed 500 micron sieve (i.e. a sieve which retains particles having a size of greater than 500 microns). The clay retained on each sieve was rinsed gently with tap water. The sieves plus retained clay were then placed in a drying oven at a temperature of 130°C for 24 hours.
Each sieve was re-weighed and the percentage of dry clay retained on the sieves was calculated using the following formula, taking into account the original moisture content of the clay as 20wt.%:
clay retained = l2.Sx[(weight of sieve + dried retained clay(g)) - (weight of clean sieve (g))J
The higher the % clay retained the better the performance of the composition in stabilising the model shale. The results obtained are shown in Table ~l .
The performance of the composition of the present invention in clay or shale stabilization is now illustrated by reference to the following examples. .
Example 1 Aqueous based compositions, were prepared comprising the components shown in Table 1. Each composition was made up to a weight of 80g with demineralised water and was contained in a 100m1 glass bottle.
A model shale (London Clay; l Og) screened to a particle size range of 2-4 mm, was added to each bottle. The bottles were then sealed with screw caps and rolled at 20rpm for 16 hours (bottle rolling test). Each sample mixture was then passed through a separate pre-weighed 500 micron sieve (i.e. a sieve which retains particles having a size of greater than 500 microns). The clay retained on each sieve was rinsed gently with tap water. The sieves plus retained clay were then placed in a drying oven at a temperature of 130°C for 24 hours.
Each sieve was re-weighed and the percentage of dry clay retained on the sieves was calculated using the following formula, taking into account the original moisture content of the clay as 20wt.%:
clay retained = l2.Sx[(weight of sieve + dried retained clay(g)) - (weight of clean sieve (g))J
The higher the % clay retained the better the performance of the composition in stabilising the model shale. The results obtained are shown in Table ~l .
9 Table 1: Results of Bottle Rolling Tests Composition % clay retained 1. 80g demineralised water (comparative) 0.8 2. 251b/bbl KCl (comparative) 9.1 3. 251b/bbl NH4C1 (comparative) 27.5 4. 251b/bbl CsCI (comparative) 79.1 5. 251b/bbl KCl + 3wt.% DCP208' (comparative) 81.9 6. 251b/bbl KCI + 3.47wt.% Activ 7' (comparative) 33.1 7. 251b/bbl LiCI (comparative) -0.9 8. 251b/bbl MgCl2 (comparative) 0.4 9. 251b/bbl CaCl2 (comparative) 0.4
10. 251b/bbl KCl + 2.Swt.% Na20'2B203'SHZO + 2.Swt.%93.6 Na20'B203'8H20
11. 251b/bbl KCl + lOwt.% Na20'B203'8H20 94.0
12. 251b/bbl NH4C1 + 2.Swt.% Na20'2B203~SH20 + 93.6 2.Swt.%
Na2O'B2O3'8H2O
Na2O'B2O3'8H2O
13. 251b/bbl CsCI + 2.Swt.% Na20'2Bz03'SH20 + 2.Swt.%96.0 Na20'B203'8H20
14. 251b/bbl KCl + 3wt.% DCP208' + 2.Swt.% Na20'2B203'SH2097.6 + ~
2.Swt.% Na20'B203'8Hz0
2.Swt.% Na20'B203'8Hz0
15. 251b/bbl KCl + 3.47wt.% Activ 7 + l.5lwt.% 97.2 Na20'2B203'SH20 +
1.96wt.% H3B03
1.96wt.% H3B03
16. 251b/bbl LiCI + 2.Swt.% Na2O'2B2O3'SH2O + 2.Swt.%77.4 Na20'B203'8H20
17. 251b/bbl MgCl2 + 2.Swt.% Na20'2B203'SH20 + 64.1 2.Swt.%
Na20'B203'8Hz0
Na20'B203'8Hz0
18. 251b/bbl CaCl2 + 2.Swt.% Na20'2B203'SH20 + 74.1 2.Swt.%
Na20'Bz03'8Hz0
Na20'Bz03'8Hz0
19. 4.Owt.% K20'2B203'SH20 (1.826wt.% B203) 80.2
20. 3.4wt.% (NH4)20'2B203'SH20 (1.826wt.% B203) 68.0 la glycol supplied by BP Chemicals zwheat starch by-product (glucose syrup) supplied by Roquette Freres The unexpectedly superior performance of the compositions comprising a source of borate ions and a source of alkaline earth) metal ions or ammonium ions in stabilizing shale (examples 10-20) is evident. The effect of adding a source of sugar (Activ 7) to a composition containing a source of borate ions and a source of alkaline earth) metal ions or ammonium ions to improve the shale stabilization performance of the composition still further is evidenced by example 15.
Example 2 The procedure in Example 1 was repeated with further compositions to assess the effect of borate ion concentration and the ratio of n:m (i.e. molar ratio of Na20:Bz03) on shale stabilization performance. The results are given in Table 2.
Table 2 - Results of Bottle Tests to Determine the Effect of Borate Ion Concentration and Ratio of n:m on Shale Stabilization Performance Composition wt.% B203 n:m % retained
Example 2 The procedure in Example 1 was repeated with further compositions to assess the effect of borate ion concentration and the ratio of n:m (i.e. molar ratio of Na20:Bz03) on shale stabilization performance. The results are given in Table 2.
Table 2 - Results of Bottle Tests to Determine the Effect of Borate Ion Concentration and Ratio of n:m on Shale Stabilization Performance Composition wt.% B203 n:m % retained
21. 10. 251b/bbl KCl + 0.25wt.% 0.183 0.67:159.5 Na20~2B203'SH20 + 0.25wt.% Na2O'B2O3'BHZO
22. 251b/bbl KCl + 1.25wt.% Na20'2B203'SHZO0.913 0.67:196.5 +
1.25wt.% Na20~B203'8H20
1.25wt.% Na20~B203'8H20
23. 251b/bbl KCl + 2.Swt.% Na2O'2B2O3'SH2O1.826 0.67:196.6 +
2.Swt.% Na20'B203'8H20
2.Swt.% Na20'B203'8H20
24. 251b/bbl KCl + 3.24wt.% H3B03 1.826 0.0:1 20.8
25. 251b/bbl KCl + 1.53wt.% NazO'2B203'SH201.826 0.20:176.1 +
1.94wt.% H3B03
1.94wt.% H3B03
26. 251b/bbl KCl + 3.82wt.% Na20'2B203'SH201.826 0.50:197.8
27. 251b/bbl KCl + 7.32wt.% Na20'Bz03'8Hz01.826 1.0:1 97.6 The results indicate that an acceptable shale stabilization performance can be achieved with compositions having a range of borate ion concentrations and a range of n:m ratios.
Example 3 Water based compositions (350 ml), were prepared comprising the components shown in Table 3 below. Each composition was made up using tap water and was prepared in a plastic bottle. To each of the bottles was added 30g of 2-4mm size range Oxford clay. The bottles were sealed and rolled at a speed of approximately 30 rpm in an oven set at a temperature of 65°C for a period of 16 hours. The compositions were then repeatedly passed through a 2mm sieve. The clay retained on the sieve was collected and oven dried for a minimum of 16 hours. The % clay retained in the test was calculated taking into account, as in Example 1, the original moisture content of the clay. The results are shown in Table 3.
Table 3 - Results of Bottle Rolling Tests using Oxford Clay Composition pH % clay retained
Example 3 Water based compositions (350 ml), were prepared comprising the components shown in Table 3 below. Each composition was made up using tap water and was prepared in a plastic bottle. To each of the bottles was added 30g of 2-4mm size range Oxford clay. The bottles were sealed and rolled at a speed of approximately 30 rpm in an oven set at a temperature of 65°C for a period of 16 hours. The compositions were then repeatedly passed through a 2mm sieve. The clay retained on the sieve was collected and oven dried for a minimum of 16 hours. The % clay retained in the test was calculated taking into account, as in Example 1, the original moisture content of the clay. The results are shown in Table 3.
Table 3 - Results of Bottle Rolling Tests using Oxford Clay Composition pH % clay retained
28. 251b1bb1 KC1 (comparative) 9.4 11.5
29. 251b/bbl KCl + 3% Glydril MC' (comparative)7.4 49.7
30. 251b/bbl KCI + 2.5% Polyseal silicate'12' 99.1 (comparative)
31. 251b/bbl KCl + 6wt.% Na20~2B203~5H209.3 40.2
32. 251b/bbl KCl + 3.47wt.% Activ 7 + 9' 102.2 1.51wt.%
Na20~2B203'SH20 + 1.96wt% H3B03 'commercial glycol shale inhibitor product 22:1 Si02:Na20 3pH adjusted value Example 4 ' A so-called Hamster Cage Test for evaluating the shale stabilizing performance of the compositions according to the present invention was performed. This test involved preparing 1500m1 of water based drilling fluid compositions as presented in Table 4 (where the aqueous liquid component of the compositions is demineralised water):
Table 4: Compositions for use in Hamster Cage Test Ingredient Drilling Fluid A Drilling Fluid B
(comparative) Ib/bbl of ingredient lb/bbl of ingredient KCl 25 25 Polyanionic cellulose'1.5 1.5 Starch' 4.0 4.0 Xanthan gum' 1.5 1.0 Na20~2B203~5Hz0 0 8.75 Na20~B203~8Hz0 0 8.75 'PAC L - supplied by Baroid 2DEXTRID - supplied by Baroid 3Xanvis - supplied by Schlumberger The viscosities of the drilling fluid compositions prepared in Table 4 were measured at a temperature of 20°C using a Fann Viscometer (Model 35SA -Baroid Testing Equipment, Texas, USA). The results of the viscosity tests are presented in Table 5.
Table 5: Viscosities of Drilling Fluid Compositions Fann viscometer readingsDrilling Fluid A Drilling Fluid B
(comparative) 600rpm 49 48 300rpm 34.5 31 200rpm 28 . 25 100rpm 19.5 17 6rpm 6 5 3rpm 4.5 4 PV / cP 14.5 17 YP / lb/100sqrft 20 14 PH 10.0 (adjusted with 9.4 NaOH) These results demonstrate that drilling fluid compositions with desired rheological properties can be formulated containing borate ions. Furthermore, the presence of borate ions enables lower levels of viscosifying polymer to be employed, and ensures that the fluid is well buffered at the correct pH.
Hamster Ca eg Test The Hamster Cage Test involved removing the lids from pre-weighed cages (of 1 mm mesh size) and adding approximately 80g of London Clay (4-8mm sieved particle size range) to each cage. The lids were replaced on the cages which were then suspended in a first and a second trough previously filled with drilling fluid compositions A and B respectively. The cages were then rotated automatically for 4 hours. At the end of this period, the cages were removed from the apparatus, the lids opened and the cages and retained cuttings rinsed with tap water. They were then dried in an oven for 16 hours at a temperature of 130°C, and finally re-weighed. The formula used in Example 1 was employed to calculate the percentage of clay cuttings retained in the cage. The results are presented in Table 6:
Table 6: Results of Hamster Cage Tests Clay Retained Drilling Fluid A (Comparative) 44.0 Drilling Fluid B 73.1 The improved shale stabihzmg pertbrmance of the drilling fluid composition containing borate ions and potassium ions (Drilling Fluid B) is evident from these results.
Example S
The fluid loss characteristics and viscosity of drilling fluid composition C, comprising the ingredients given in Table 7, were measured before and after high temperature ageing (hot rolling) at a temperature of 120°C for 16 hours. The results are presented in Table 8.
Table 7: Drilling Fluid Composition C
Ingredient lb/bbl of Ingredient KCl 25 Polyanionic cellulose 1.5 Starch 4.0 Xanthan Gum 1.5 Na20-2B203~SH20 8.75 Na20~Bz03~8Hz0 8.75 Barite 100 HMP' 10 1 HMP = Hymod Prima clay obtained from Imerys comprising illite and having a particle size of about 1 to S microns. HMP is a non-swelling clay and simulates drilled solids (cuttings) in the formulation.
Table 8: Viscosity and Fluid Loss Characteristics of Un-aged and Aged (16 hours at 120°C) Samples of Drilling Fluid Composition C
Fann viscometer readingsUn-aged Aged 600rpm 90 85 300rpm 62 59 200rpm 50 ~ 47 100rpm 36 ' 34 6rpm 12 12 3rpm 9 10 Gel / l Os 11 14 PV / cP 28 26 YP / Ib/100sqrft 34 33 Fluid loss l min 0.0 0.1 7.5 min 0.6 0.9 30 min 2.9 3.7 pH 9.5 9.3 The fluid loss characteristics of drilling fluid composition C are good and this property together with the viscosity of the drilling fluid composition remain substantially unaltered despite high temperature ageing.
Na20~2B203'SH20 + 1.96wt% H3B03 'commercial glycol shale inhibitor product 22:1 Si02:Na20 3pH adjusted value Example 4 ' A so-called Hamster Cage Test for evaluating the shale stabilizing performance of the compositions according to the present invention was performed. This test involved preparing 1500m1 of water based drilling fluid compositions as presented in Table 4 (where the aqueous liquid component of the compositions is demineralised water):
Table 4: Compositions for use in Hamster Cage Test Ingredient Drilling Fluid A Drilling Fluid B
(comparative) Ib/bbl of ingredient lb/bbl of ingredient KCl 25 25 Polyanionic cellulose'1.5 1.5 Starch' 4.0 4.0 Xanthan gum' 1.5 1.0 Na20~2B203~5Hz0 0 8.75 Na20~B203~8Hz0 0 8.75 'PAC L - supplied by Baroid 2DEXTRID - supplied by Baroid 3Xanvis - supplied by Schlumberger The viscosities of the drilling fluid compositions prepared in Table 4 were measured at a temperature of 20°C using a Fann Viscometer (Model 35SA -Baroid Testing Equipment, Texas, USA). The results of the viscosity tests are presented in Table 5.
Table 5: Viscosities of Drilling Fluid Compositions Fann viscometer readingsDrilling Fluid A Drilling Fluid B
(comparative) 600rpm 49 48 300rpm 34.5 31 200rpm 28 . 25 100rpm 19.5 17 6rpm 6 5 3rpm 4.5 4 PV / cP 14.5 17 YP / lb/100sqrft 20 14 PH 10.0 (adjusted with 9.4 NaOH) These results demonstrate that drilling fluid compositions with desired rheological properties can be formulated containing borate ions. Furthermore, the presence of borate ions enables lower levels of viscosifying polymer to be employed, and ensures that the fluid is well buffered at the correct pH.
Hamster Ca eg Test The Hamster Cage Test involved removing the lids from pre-weighed cages (of 1 mm mesh size) and adding approximately 80g of London Clay (4-8mm sieved particle size range) to each cage. The lids were replaced on the cages which were then suspended in a first and a second trough previously filled with drilling fluid compositions A and B respectively. The cages were then rotated automatically for 4 hours. At the end of this period, the cages were removed from the apparatus, the lids opened and the cages and retained cuttings rinsed with tap water. They were then dried in an oven for 16 hours at a temperature of 130°C, and finally re-weighed. The formula used in Example 1 was employed to calculate the percentage of clay cuttings retained in the cage. The results are presented in Table 6:
Table 6: Results of Hamster Cage Tests Clay Retained Drilling Fluid A (Comparative) 44.0 Drilling Fluid B 73.1 The improved shale stabihzmg pertbrmance of the drilling fluid composition containing borate ions and potassium ions (Drilling Fluid B) is evident from these results.
Example S
The fluid loss characteristics and viscosity of drilling fluid composition C, comprising the ingredients given in Table 7, were measured before and after high temperature ageing (hot rolling) at a temperature of 120°C for 16 hours. The results are presented in Table 8.
Table 7: Drilling Fluid Composition C
Ingredient lb/bbl of Ingredient KCl 25 Polyanionic cellulose 1.5 Starch 4.0 Xanthan Gum 1.5 Na20-2B203~SH20 8.75 Na20~Bz03~8Hz0 8.75 Barite 100 HMP' 10 1 HMP = Hymod Prima clay obtained from Imerys comprising illite and having a particle size of about 1 to S microns. HMP is a non-swelling clay and simulates drilled solids (cuttings) in the formulation.
Table 8: Viscosity and Fluid Loss Characteristics of Un-aged and Aged (16 hours at 120°C) Samples of Drilling Fluid Composition C
Fann viscometer readingsUn-aged Aged 600rpm 90 85 300rpm 62 59 200rpm 50 ~ 47 100rpm 36 ' 34 6rpm 12 12 3rpm 9 10 Gel / l Os 11 14 PV / cP 28 26 YP / Ib/100sqrft 34 33 Fluid loss l min 0.0 0.1 7.5 min 0.6 0.9 30 min 2.9 3.7 pH 9.5 9.3 The fluid loss characteristics of drilling fluid composition C are good and this property together with the viscosity of the drilling fluid composition remain substantially unaltered despite high temperature ageing.
Claims (20)
1. A method of reducing the swelling of shale or clay encountered during drilling a wellbore, the method comprising circulating in the wellbore a composition comprising:
(a) a continuous aqueous phase;
(b) a source of borate ions;
(c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions; and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
(a) a continuous aqueous phase;
(b) a source of borate ions;
(c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions; and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups.
2. A method of reducing the swelling of shale or clay encountered during the drilling of a wellbore through a formation using a drill string disposed within the wellbore, said drill string having a first end and a second end, the first end of the drill string being located at or near the surface of the wellbore and the second end of the drill string being in communication with a drill bit having ports therein, wherein:
(A) a drilling fluid composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions, and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups is introduced into the first end of the drill string, is pumped through the drill string from the first end to the second end thereof and is discharged into the wellbore through the ports in the drill bit; and (B) the drilling fluid composition is recycled to the first end of the drill string via an annular space which is provided between the drill string and the walls of the wellbore.
(A) a drilling fluid composition comprising (a) a continuous aqueous phase, (b) a source of borate ions, (c) a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions, and (d) optionally a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides having from 2 to 4 saccharide groups is introduced into the first end of the drill string, is pumped through the drill string from the first end to the second end thereof and is discharged into the wellbore through the ports in the drill bit; and (B) the drilling fluid composition is recycled to the first end of the drill string via an annular space which is provided between the drill string and the walls of the wellbore.
3. A method according to claims 1 or 2 wherein the source of borate ions is selected from the group consisting of sodium borates, potassium borates, caesium borates, ammonium borates, and boric acid.
4. A method according to claim 3 wherein the source of borate ions is selected from the group consisting of:
Disodium tetraborate pentahydrate ~ Na2O'2B2O3'5H2O (borax pentahydrate), Disodium tetraborate decahydrate - Na2O'2B2O3'10H2O (borax decahydrate, tincal), Disodium tetraborate tetrahydrate - Na2O'2B2O3'4H2O (kernite), Disodium tetraborate -Na2O'2B2O3 (anhydrous borax), Sodium metaborate tetrahydrate - Na2O'B2O3'8H2O, Sodium metaborate dihydrate - Na2O'B2O3'4H2O, Sodium pentaborate pentahydrate - Na2O'5B2O3'10H2O, Disodium octaborate tetrahydrate - Na2O'4B2O3'4H2O, Boric acid ~ H3BO3, Dipotassium tetraborate tetrahydrate - K2O'2B2O3'4H2O, Potassium pentaborate tetrahydrate - K2O'5B2O3'8H2O, Diammonium tetraborate tetrahydrate ~ (NH4)2O'2B2O3'4H2O, Ammonium pentaborate tetrahydrate - (NH4)2O'5B2O3'8H2O, and Caesium pentaborate tetrahydrate - Cs2O'5B2O3'8H2O.
Disodium tetraborate pentahydrate ~ Na2O'2B2O3'5H2O (borax pentahydrate), Disodium tetraborate decahydrate - Na2O'2B2O3'10H2O (borax decahydrate, tincal), Disodium tetraborate tetrahydrate - Na2O'2B2O3'4H2O (kernite), Disodium tetraborate -Na2O'2B2O3 (anhydrous borax), Sodium metaborate tetrahydrate - Na2O'B2O3'8H2O, Sodium metaborate dihydrate - Na2O'B2O3'4H2O, Sodium pentaborate pentahydrate - Na2O'5B2O3'10H2O, Disodium octaborate tetrahydrate - Na2O'4B2O3'4H2O, Boric acid ~ H3BO3, Dipotassium tetraborate tetrahydrate - K2O'2B2O3'4H2O, Potassium pentaborate tetrahydrate - K2O'5B2O3'8H2O, Diammonium tetraborate tetrahydrate ~ (NH4)2O'2B2O3'4H2O, Ammonium pentaborate tetrahydrate - (NH4)2O'5B2O3'8H2O, and Caesium pentaborate tetrahydrate - Cs2O'5B2O3'8H2O.
5. A method according to any one of the preceding claims wherein the concentration of borate expressed as B2O3 in the continuous aqueous phase is in the range 0.1 to 150lb/bbl.
6. A method according to any one of the preceding claims wherein the source of the alkali metal ions, alkaline earth metal ions and ammonium ions is a water soluble salt of an alkali(ne earth) metal, a water soluble ammonium salt or mixtures thereof.
7. A method according to Claim 6 wherein the salt is selected from the group consisting of potassium salts, caesium salts, and ammonium salts.
8. A method according to claim 7 wherein the salt is selected from the group consisting of potassium bromide, caesium bromide, ammonium bromide, potassium chloride, caesium chloride, ammonium chloride, potassium hydroxide, caesium hydroxide and ammonium hydroxide.
9. - A method according to any one of claims 6 to 8 wherezn the concentration of alkali metal salt, alkaline earth metal salt or ammonium salt in the contil-IUOU.s aqueous phase is in the range 0.1 to 150lblbbl.
I 0. A method according to any one of the preceding claims wherein the sugar is selected from the group consisting of glucose, fructose, sucrose, maltose, lactose and mixiures th~reaf.
11. A method according to any one of the preceding claims wherein the concentration of, sugar in the continuous aqueous phase is in the range 0.1 to I ~0 llbl6bl.
I 2. A method according to any one of the preceding claims wherein the composition comprises additional additives selected from tha group consisting of weighting agents, viscosifiers, fluid loss control agents, defoamers, lubricants, .and gl ycols.
I3. A composition comprising (a) a continuous aqueous phase (b) a source ofborate ions, (c) a source of ions selected from the group -consisting of alkali metal ions, alkaline earth me',.a1 ions and ammonium ions~and {d) a source of at least one sugar selected from the group consisting of monosaccharides and oligosaccharides hawing from 2 to 4 saccharide groups.
14. A composition as claimed in claim I3 having the features defined in any one of claims 3 to 12.
1 ~. A concentrate comprising a source of borate ions, a source of ions selected from the group consisting of alkali metal ions, alkaline earth metal ions and ammonium ions and a source of at feast one sugar selected frog the soup consisting 'of manosaccharides and oligosaccharides having from 2 to 4 saccharide groups dissolved or dispersed in an aqueous phase.
1.6. A concentrate as claimed in claim IS wherein the concentration ofborate, expressed as B~~, is in the range 10 to 250 Ib/bbl, the concentration of alkali metal salt, alkaline earth metal salt or ammonium salt is in the range IO to 130 lb/bbl and the concentration of sugar zs in tha range 10 to 300 Iblbbl.
I7. A concentrate as claimed in claims IS or 16 wherein the source of borate ioLls 1S aS deiuled in claims 3 or 4.
18. A concentrate as claimed in any one of claims 15 to 17 wherein the source of the alkali metal ions, alkaline earth metal ions or the ammonium ions is as defined in any one of claims 6 to 8.
19. A concentrate as claimed in any one of claims 15 to 18 wherein the source of the sugar is as defined in claim 10.
20. Use of a composition according to claims 13 or 14 as a drilling fluid.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB0130110.0A GB0130110D0 (en) | 2001-12-17 | 2001-12-17 | Composition |
| GB0130110.0 | 2001-12-17 | ||
| PCT/GB2002/005635 WO2003052023A1 (en) | 2001-12-17 | 2002-12-12 | Method of stabilising clay or shale |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2469051A1 true CA2469051A1 (en) | 2003-06-26 |
Family
ID=9927750
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002469051A Abandoned CA2469051A1 (en) | 2001-12-17 | 2002-12-12 | Method of stabilising clay or shale |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US20050014655A1 (en) |
| EP (1) | EP1453932A1 (en) |
| AU (1) | AU2002350945A1 (en) |
| CA (1) | CA2469051A1 (en) |
| GB (1) | GB0130110D0 (en) |
| NO (1) | NO20042827L (en) |
| RU (1) | RU2004122107A (en) |
| WO (1) | WO2003052023A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004026987A1 (en) * | 2002-09-17 | 2004-04-01 | M-Il.L.C. | Membrane forming in-situ polymerization for water based drilling fluids |
| US8703658B2 (en) | 2007-03-09 | 2014-04-22 | Canadian Energy Services L.P. | Drilling fluid and methods |
| CA2594108C (en) * | 2007-03-09 | 2014-06-03 | Techstar Energy Services Inc. | Drilling fluid and methods |
| CN101688109B (en) | 2007-07-26 | 2015-03-25 | 埃克森美孚上游研究公司 | Method for controlling loss of drilling fluid |
| US20130333888A1 (en) * | 2012-06-19 | 2013-12-19 | Marco Tulio Rincon-Torres | Self-degrading ionically cross-linked biopolymer composition for well treatment |
| US10053935B2 (en) * | 2013-07-03 | 2018-08-21 | Baker Hughes, A Ge Company, Llc | Lubricating compositions for use with downhole fluids |
| WO2015041669A1 (en) | 2013-09-20 | 2015-03-26 | Halliburton Energy Services, Inc. | Methods for enhancing and maintaining fracture conductivity after fracturing shale formations without proppant placement |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2785125A (en) * | 1955-10-17 | 1957-03-12 | Exxon Research Engineering Co | Drilling muds |
| US3177142A (en) * | 1962-06-21 | 1965-04-06 | Texaco Inc | Drilling fluid |
| US4257903A (en) * | 1978-10-19 | 1981-03-24 | The Dow Chemical Company | Drilling fluid containing crosslinked polysaccharide derivative |
| US4546252A (en) * | 1984-07-25 | 1985-10-08 | Mobil Oil Corporation | Method for monitoring potassium chloride concentration in drilling fluids |
| US4948428A (en) * | 1988-09-14 | 1990-08-14 | Baroid Technology, Inc. | Grouting composition and method for grouting conduits in well bores |
| US5281270A (en) * | 1992-02-19 | 1994-01-25 | Halliburton Company | Retarded acid soluble well cement compositions and methods |
| US5445223A (en) * | 1994-03-15 | 1995-08-29 | Dowell, A Division Of Schlumberger Technology Corporation | Delayed borate crosslinked fracturing fluid having increased temperature range |
| GB9822797D0 (en) * | 1998-10-19 | 1998-12-16 | United States Borax Inc | Pourable aqueous boron-containing compositions and their preparation |
| US6258756B1 (en) * | 1999-01-26 | 2001-07-10 | Spectral, Inc. | Salt water drilling mud and method |
| RU2186820C1 (en) * | 2001-05-23 | 2002-08-10 | Общество с ограниченной ответственностью "ПермНИПИнефть" | Clayless drilling mud for controlled directional and horizontal holes and for exposing productive formations (versions) |
| US6617285B2 (en) * | 2001-07-03 | 2003-09-09 | Baker Hughes Incorporated | Polyols for breaking of borate crosslinked fracturing fluid |
| US20030092584A1 (en) * | 2001-11-13 | 2003-05-15 | Crews James B. | Deep water completions fracturing fluid compositions |
-
2001
- 2001-12-17 GB GBGB0130110.0A patent/GB0130110D0/en not_active Ceased
-
2002
- 2002-12-12 CA CA002469051A patent/CA2469051A1/en not_active Abandoned
- 2002-12-12 US US10/499,333 patent/US20050014655A1/en not_active Abandoned
- 2002-12-12 WO PCT/GB2002/005635 patent/WO2003052023A1/en not_active Application Discontinuation
- 2002-12-12 AU AU2002350945A patent/AU2002350945A1/en not_active Abandoned
- 2002-12-12 RU RU2004122107/03A patent/RU2004122107A/en not_active Application Discontinuation
- 2002-12-12 EP EP02785658A patent/EP1453932A1/en not_active Withdrawn
-
2004
- 2004-07-05 NO NO20042827A patent/NO20042827L/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| NO20042827L (en) | 2004-09-17 |
| GB0130110D0 (en) | 2002-02-06 |
| EP1453932A1 (en) | 2004-09-08 |
| US20050014655A1 (en) | 2005-01-20 |
| WO2003052023A1 (en) | 2003-06-26 |
| AU2002350945A1 (en) | 2003-06-30 |
| RU2004122107A (en) | 2005-06-27 |
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| FZDE | Discontinued |