Water-wettable drilling mud additives containing uintaite
AssigneeAmerican Gilsonite Company
InventorsK. Clark Christensen, Neal Davis, II, Michael Nuzzolo
Life of this patent
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Abstract
A water-based drilling mud additive comprising a preblended combination of about 2 parts of high softening point uintaite, about 1 part of a lower softening point uintaite, about 1 part of causticized lignite, and a strongly lipophilic, non-ionic surfactant is disclosed. This composition decreases shale sloughing and bore-hole instability during drilling of wells.
Claims66
A method of preparing a water-wettable drilling mud additive comprising the steps of:
- mixing together about 2 parts of a high softening point uintaite solid having a softening point of at least 360.degree. F., and about 1 part a low softening point uintaite solid having a softening point of about 330.degree. F. or lower;
- adding causticized lignite and a strongly lipophilic surfactant.
A method as described in claim [11] 1 , wherein said lignite is added while pulverizing the uintaite solids and wherein said surfactant is added by spraying.
A water-wettable drilling mud additive that stabilizes a borehole during well drilling, comprising a preblended stabilizing combination of about 2 parts of a high softening point uintaite to about 1 part of a low softening point uintaite, combined with causticized lignite and a strongly lipophilic non-ionic surfactant which provides a rewetting index of less than about 4 to the uintaites, wherein the softening point of said uintaites are about 40.degree. F. apart or greater.
A water-wettable drilling mud additive comprising a mixture of:
- (a) 45 to 55 percent of a high softening point uintaite having a softening [pint] point above about 375.degree. F.;
- (b) 20 to 30 percent a low softening point uintaite having a softening point below about 330.degree. F.;
- (c) 20 to 30 percent of causticized lignite;
- and
- (d) 2 to 4 percent a strongly lipophilic non-ionic surfactant which provides a rewetting index of less than about 4 to the uintaites.
A drilling mud additive for stabilizing boreholes during well drilling , comprising:
- a pre-blended, borehole stabilizing mixture of a high softening point uintaite having a softening point of at least 360.degree. F., a low softening point uintaite having a softening point of about 330.degree. F. or lower, causticized lignite, and a surfactant that provides the uintaites with a rewetting index of less than about 4, wherein the ratio of said high softening point uintaite to said low softening point uintaite is about 2 to 1.
A water-wettable drilling mud additive that stabilizes a borehole during well drilling, comprising a preblended stabilizing combination of a high softening point uintaite, having a softening point of at least 360.degree. F., a low softening point uintaite having a softening point of about 330.degree. F. or lower, causticized lignite, and a strongly lipophilic non-ionic surfactant which provides a rewetting index of less than about 4 to the uintaites, wherein the ratio of said high softening point uintaite to said low softening point uintaite is about 2 to 1.
A method of preparing a water-wettable drilling mud additive comprising the steps of:
- mixing together a high softening point uintaite solid having a softening point of at least 360.degree. F., and a low softening point uintaite solid having a softening point of about 330.degree. F. or lower;
- and adding causticized lignite and a surfactant effective to decrease the rewetting index of the uintaites, wherein the weight ratio of said uintaites to said causticized lignite is between about 3:1 to about 4:1.
A water-wettable drilling mud additive that stabilizes a borehole during well drilling, comprising a preblended stabilizing combination of a high softening point uintaite and a low softening point uintaite, combined with a causticized lignite and a surfactant effective to decrease the rewetting index of the uintaites, wherein the softening point of said uintaites are about 40.degree. F. apart or greater and wherein the weight ratio of uintaites to said causticized lignite is about between about 3:1 to about 4:1.
A drilling mud additive for stabilizing boreholes during well drilling, comprising:
- a pre-blended, borehole stabilizing mixture of a high softening point uintaite having a softening point of at least 360.degree. F., a low softening point uintaite having a softening point of about 330.degree. F. or lower, causticized lignite, and a surfactant effective to decrease the rewetting index of the uintaites, wherein the weight ratio of uintaites to said causticized lignite is between about 3:1 to about 4:1.
A method of preparing a water-wettable drilling mud additive comprising the steps of:
- a) mixing together about a high softening point uintaite solid having a softening point of at least 360.degree. F., a low softening point uintaite solid having a softening point of about 330.degree. F. or lower;
- b) melting the mixture of step a;
- c) dissolving or trapping a surfactant effective to decrease the rewetting index of the uintaites in the molten mixture of step b;
- d) solidifying the mixture of step c;
- e) pulverizing the mixture of step d;
- and
- f) adding causticized lignite, wherein the weight ratio or uintaites to said causticized lignite is between about 3:1 to about 4:1.
A water-wettable additive for water-based drilling fluids that stabilizes a borehole during well drilling, comprising a pre-blended stabilizing combination including causticized lignite, a high softening point uintaite, an amount of low softening point uintaite effective to stabilize boreholes over a temperature range of between about 125.degree. F to about 250.degree. F, and a surfactant effective to
- decrease the rewetting index of the uintaites.
A drilling mud additive for stabilizing boreholes during well drilling, comprising a pre-blended borehole stabilizing mixture of causticized lignite, a high softening point uintaite, an amount of low softening point uintaite effective to stabilize boreholes over a temperature range of between about 125.degree. F, and about 250.degree. F, and a surfactant which is effective to decrease the rewetting index of the uintaites.
A method of preparing a water-wettable drilling mud additive for stabilizing boreholes during well drilling, comprising the steps of mixing a high softening point uintaite with an amount of low softening point uintaite effective to stabilize boreholes over a temperature range of between about 125.degree. F and 250.degree. F, and adding causticized lignite and a surfactant effective to decrease the rewetting index of the uintaites.
A method of drilling a well, comprising the steps of inserting a drill bit into the well to form a bore-hole and circulating a drilling mud into said bore-hole and through said well during said drilling, said drilling mud containing a water-wettable additive for water-based drilling fluids that stabilizes a borehole during well drilling, said additive including a pre-blended stabilizing combination including a high softening point uintaite, an amount of low softening point uintaite effective to stabilize boreholes at a temperature above about 125.degree. F, and a surfactant effective to decrease the rewetting index of the uintaites, said additive being effective to substantially reduce sloughing shales and bore-hole erosion to thereby reduce bore-hole collapse, while increasing bore-hole
- lubrication.
Dependencies are inferred from the claim text.