Biodegradable lubricating composition and use thereof in a drilling fluid, in particular for very deep reservoirs
The present disclosure relates to a biodegradable lubricant composition, notably intended to be incorporated as an oil phase with high lubricating power in a drilling fluid or mud. This composition may be in a drilling fluid or as a fluid for fracture of underground formations. These muds or fluids contained in the composition of the present disclosure are particularly suitable for very deep drillings, offshore in deep water and/or sidetracked drillings or with a long shift.
1. A drilling fluid comprising, as an oil phase, a lubricant composition having an aerobic biodegradability rate of more than 20% measured according to OECD 306, said lubricant composition being based on a hydrocarbon mineral oil and on tall oil fatty acid(s), the lubricant composition comprising:
between 99.95 and 90% by weight of a hydrocarbon oil having:
a boiling temperature in the range from 220 to 350° C.;
an aromatic content measured according to IP 391 of less than or equal to 1% by mass;
a kinematic viscosity at 40° C. according to NF T 60100 method comprised between 1.8 and 4 mm 2 /s; and
between 40 ppm and 10% by weight of a composition comprising from 80 to 100% by weight of tall oil fatty acid(s).
2. The drilling fluid of claim 1 , comprising between 99 and 95% by weight of the hydrocarbon oil.
3. The drilling fluid of claim 1 , comprising between 40 ppm and 5% by weight of the composition comprising from 80 to 100% by weight of tall oil fatty acid(s).
4. The drilling fluid of claim 1 , as a mixture with resin acids.
5. The drilling fluid of claim 1 , wherein the aromatic content of the hydrocarbon oil is less than or equal to 0.1% by mass.
6. The drilling fluid of claim 1 , wherein the hydrocarbon oil is free of aromatics.
7. The drilling fluid according to claim 1 , wherein the hydrocarbon oil is of mineral origin (from petroleum and/or from coal (Coal to Liquid) and/or from gas (Gas to Liquid)) and/or from a renewable animal and/or plant source.
8. The drilling fluid of claim 7 , wherein the hydrocarbon oil is from biomass (BTL).
9. The drilling fluid of claim 8 , wherein the hydrocarbon oil is from the hydrotreatment and isomerization of vegetable oil esters.
10. The drilling fluid according to claim 1 , for very deep drillings.
11. The drilling fluid according to claim 10 , wherein the deep drillings are offshore in deep water and/or sidetracked drillings and/or with a long shift.
12. The drilling fluid according to claim 3 , further comprising between 140 ppm and 3% by weight of the composition comprising from 80 to 100% by weight of tall oil fatty acid(s).