초록

Wax-containing crude oils are treated with polyvinyl alcohol, which is optionally cross-linked, to improve the mobility of the oil and thereby facilitate its transport between its point of production and a point downstream thereof.

대표청구항 ▼

1. A method of treating a wax-containing material for improving the mobility thereof, wherein said wax-containing material is arranged to flow along a fluid flow path and has a Wax Appearance Temperature (WAT) before contact with a treatment fluid formulation of less than 100° C., said method compri

1. A method of treating a wax-containing material for improving the mobility thereof, wherein said wax-containing material is arranged to flow along a fluid flow path and has a Wax Appearance Temperature (WAT) before contact with a treatment fluid formulation of less than 100° C., said method comprising contacting the wax-containing material in said fluid flow path with a said treatment fluid formulation, said treatment fluid formulation comprising a polymeric material AA which includes —O— moieties pendent from a polymeric backbone thereof, wherein polymeric material AA is optionally cross-linked and wherein said treatment fluid formulation is initially contacted with said wax-containing material in said fluid flow path below ground. 2. A method according to claim 1, wherein said wax-containing material has a Wax Appearance Temperature (WAT) before contact with said treatment fluid formulation of less than 80° C. 3. A method according to claim 1, wherein said wax-containing material has a pour point measured in accordance with ASTM D97 of less than 150° C. 4. A method according to claim 1, wherein said wax-containing material comprises a material derived from an heavy oil reservoir and/or from tar sand deposits. 5. A method according to claim 1, wherein said treatment fluid formulation is initially contacted with said wax-containing material at or downstream of a position in a fluid flow path wherein light fractions of a live oil have been removed. 6. A method according to claim 1, wherein said wax-containing material is at a temperature above its pour point when initially contacted with said treatment fluid formulation. 7. A method according to claim 1, wherein said treatment fluid formulation is arranged to disperse and/or emulsify said wax-containing material on contact therewith. 8. A method according to claim 1, wherein the mass fraction of wax-containing material in said fluid flow path after contact with said treatment fluid formulation is in the range 0.4 to 0.8. 9. A method according to claim 1, wherein immediately after contact between said wax-containing material and said treatment fluid formulation, the composition in said fluid flow path includes at least 40 wt % of water and at least 50 wt % of said wax-containing material. 10. A method according to claim 1, wherein said treatment fluid formulation includes at least 95 wt % water. 11. A method according to claim 1, wherein said treatment fluid formulation includes at least 0.2 wt % of said polymeric material AA and less than 10 wt % of said polymeric material AA. 12. A method according to claim 1, wherein said treatment fluid formulation includes 98.0 to 99.6 wt % water and 0.4 to 2.0 wt % of said polymeric material AA; and the ratio of the wt % of said treatment fluid formulation to the wt % of said wax-containing material contacted in the method is in the range 0.5 to 1.5. 13. A method according to claim 1, wherein said polymeric material AA includes a moiety of formula: where G1 and G2 are other parts of the polymeric backbone and G3 is another moiety pendent from the polymeric backbone. 14. A method according to claim 1, wherein said polymeric material AA includes a moiety 15. A method according to claim 1, wherein the ratio of the number of acetate groups to the number of hydroxyl groups in said polymeric material AA is in the range 0.01 to 1. 16. A method according to claim 1, wherein said polymeric material AA has a number average molecular weight (Mn) of at least 10,000 and less than 500,000. 17. A method according to claim 1, wherein said polymeric material AA is a polyvinyl alcohol polymer or copolymer. 18. A method according to claim 1, which includes the step of separating at least a part of the treatment fluid formulation from the wax-containing material after the wax-containing material has flowed along said fluid flow path. 19. A method according to claim 1, wherein said polymeric material AA comprises 70 to 90% hydrolyzed polyvinylacetate. 20. A method according to claim 1, wherein a delivery flow path is defined which is arranged to communicate with said fluid flow path wherein said treatment fluid formulation is dosed into said wax-containing material in said fluid flow path via said delivery flow path. 21. A method according to claim 20, wherein the ratio of the flow rate (in weight per unit time) of treatment fluid formulation in said delivery flow path to the flow rate (in the same unit) of wax-containing material in said fluid flow path is in the range 0.1 to 2.5. 22. A method according to claim 1, which includes a pre-treatment step which comprises contacting a wax-containing crude oil with a pre-treatment fluid thereby to prepare the wax-containing material for contact with the treatment fluid formulation in the method. 23. A method according to claim 22, wherein said pre-treatment fluid comprises a chemical arranged to reduce the pour point of the wax-containing crude oil. 24. A method according to claim 22, wherein said pre-treatment fluid is an alcohol or aromatic compound, a hydrocarbon, naphthalene, an amine salt of a sulphonic acid; a long chain alkyl ester, a lignin based system, a sulphonic acid based system, a naphthalene sulphonic acid condensate or a solvent, for example kerosene or naphthalene. 25. A method of treating a wax-containing material for improving the mobility thereof, wherein said wax-containing material is arranged to flow along a fluid flow path and has a Wax Appearance Temperature (WAT) before contact with a treatment fluid formulation of less than 100° C., said method comprising contacting the wax-containing material in said fluid flow path with a said treatment fluid formulation, said treatment fluid formulation comprising a polymeric material AA having a number average molecular weight of at least 10,000 and less than 400,000, said polymeric material AA including —OR10 moieties pendent from a polymeric backbone thereof, wherein at least 50% of groups —O—R10 are hydroxyl groups and wherein said treatment fluid formulation is initially contacted with said wax-containing material in said fluid flow path below ground. 26. A method of treating a wax-containing material for improving the mobility thereof, wherein said wax-containing material is arranged to flow along a fluid flow path and has a Wax Appearance Temperature (WAT) before contact with a treatment fluid formulation of less than 100° C., said method comprising contacting the wax-containing material in said fluid flow path with a said treatment fluid formulation, said treatment fluid formulation comprising a polymeric material AA which comprises 70 to 90% hydrolysed polyvinylacetate, wherein said treatment fluid formulation is initially contacted with said wax-containing material in said fluid flow path below ground and wherein immediately after contact between said wax-containing material and said treatment fluid formulation, the composition in said fluid flow path includes at least 40 wt % water.