In order to substantially reduce friction during drilling operations, specialized lubricants need to be added to drilling fluid recipes. In general, lubricants reduce friction by forming a thin film of liquid that separates the solid surfaces in contact. The primary objective of this research is to evaluate the performance of enhanced activated sludge (EAS) as a lubricant in drilling fluids. EAS is activated sludge rich in lipids. The mixed consortium of microorganism in waste water treatment facilities in grown under a high carbon/nitrogen ratio to trigger lipid accumulation. Performance of EAS as drilling fluid additive was compared with commercial lubricants in terms of lubricity and flow properties. Lubricants were evaluated using water-based drilling mud at lubricant concentrations of 1.78, 3.11, 4.43, and 6.17 pounds per barrel (ppb). Experiments were carried out in a standard lubricity meter. The lubricity meter tests the ability of the lubricant in the drilling mud to reduce friction. Other parameters measured were plastic viscosity, gel strength, fluid loss, mud cake thickness, sand content, methylene blue test (MBT), alkalinity, and chlorides. These findings show that EAS will improve the properties of water-based drilling mud.

In order to substantially reduce friction during drilling operations, specialized lubricants need to be added to drilling fluid recipes. In general, lubricants reduce friction by forming a thin film of liquid that separates the solid surfaces in contact. The primary objective of this research is to evaluate the performance of enhanced activated sludge (EAS) as a lubricant in drilling fluids. EAS is activated sludge rich in lipids. The mixed consortium of microorganism in waste water treatment facilities in grown under a high carbon/nitrogen ratio to trigger lipid accumulation. Performance of EAS as drilling fluid additive was compared with commercial lubricants in terms of lubricity and flow properties. Lubricants were evaluated using water-based drilling mud at lubricant concentrations of 1.78, 3.11, 4.43, and 6.17 pounds per barrel (ppb). Experiments were carried out in a standard lubricity meter. The lubricity meter tests the ability of the lubricant in the drilling mud to reduce friction. Other parameters measured were plastic viscosity, gel strength, fluid loss, mud cake thickness, sand content, methylene blue test (MBT), alkalinity, and chlorides. These findings show that EAS will improve the properties of water-based drilling mud.

A method includes introducing into a drilling fluid a plurality of tags having a first clay nanoparticle and a first polymer embedded into the clay nanoparticle and circulating the drilling fluid and tags through a well during a drilling operation that creates formation cuttings such that the tags interact with the formation cuttings, creating tagged cuttings. The returned cuttings are collected from the circulating drilling fluid at a surface of the well, and the tags on the returned cuttings are detected to identify the tagged cuttings. The method also includes correlating the tagged cuttings with a drill depth in the well from the drilling operation.

The organophilic clay comprises a smectite-type clay ion exchanged with quaternary ammonium ions, where at least 75 mol-% of said quaternary ammonium ions are bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters and at least 90% of the fatty acid moieties of the bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters have a structure RC(O) with group R being a linear alkyl or alkenyl group containing from 9 to 21 carbon atoms. The organophilic clay is useful for thickening oil based compositions, in particular drilling fluids for drilling oil or gas wells, comprising an oil phase.

The organophilic clay comprises a smectite-type clay ion exchanged with quaternary ammonium ions, where at least 75 mol-% of said quaternary ammonium ions are bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters and at least 90% of the fatty acid moieties of the bis-(2-hydroxypropyl)-dimethylammonium fatty acid esters have a structure RC(O) with group R being a linear alkyl or alkenyl group containing from 9 to 21 carbon atoms. The organophilic clay is useful for thickening oil based compositions, in particular drilling fluids for drilling oil or gas wells, comprising an oil phase.

A fluid pressure transmission pill (FPTP) having an ultra-high viscosity for use in association with hydrocarbon drilling and exploration operations, particularly, managed pressure drilling (MPD) operations, is described. The ultra-high viscosity pill is a weighted pill composition that includes a hydrocarbon fluid, a thixotropic viscosifying agent, one or more activators, an emulsifier/wetting agent, a fluid loss control additive, and a weighting material. In accordance with selected aspects of the described fluid pressure transmission pill, the ratio of the amount of the thixotropic viscosifying agent to the activator is a ratio of about 7:1, and the weighting material is a barium-containing solid-phase material. Also described are methods of use of such FPTP products in subterranean operations, such as well killing operations during managed pressure drilling.

A fluid pressure transmission pill (FPTP) having an ultra-high viscosity for use in association with hydrocarbon drilling and exploration operations, particularly, managed pressure drilling (MPD) operations, is described. The ultra-high viscosity pill is a weighted pill composition that includes a hydrocarbon fluid, a thixotropic viscosifying agent, one or more activators, an emulsifier/wetting agent, a fluid loss control additive, and a weighting material. In accordance with selected aspects of the described fluid pressure transmission pill, the ratio of the amount of the thixotropic viscosifying agent to the activator is a ratio of about 7:1, and the weighting material is a barium-containing solid-phase material. Also described are methods of use of such FPTP products in subterranean operations, such as well killing operations during managed pressure drilling.

The present invention relates to the well drilling field in petroleum industry, in particular to a drilling fluid additive composition that contains a lubricant, an emulsifier, and a rheological modifier, wherein, the lubricant contains: graphite oxide and a biquaternary ammonium salt compound in which the cation part is represented by formula (1); the emulsifier is one or more of compounds represented by formula (I); the rheological modifier is a dimer acid-organic amine copolymer comprising structural units from dimer acid, structural units from alkylamine and structural units from arylamine. The present invention further provides an oil-based drilling fluid containing the composition and a use thereof. The oil-based drilling fluid containing the composition provided in the present invention obtains a lower lubrication coefficient, and favorable rheological property and thermostability, and is suitable for use in operation at a high temperature.

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The present invention relates to the well drilling field in petroleum industry, in particular to a drilling fluid additive composition that contains a lubricant, an emulsifier, and a rheological modifier, wherein, the lubricant contains: graphite oxide and a biquaternary ammonium salt compound in which the cation part is represented by formula (1); the emulsifier is one or more of compounds represented by formula (I); the rheological modifier is a dimer acid-organic amine copolymer comprising structural units from dimer acid, structural units from alkylamine and structural units from arylamine. The present invention further provides an oil-based drilling fluid containing the composition and a use thereof. The oil-based drilling fluid containing the composition provided in the present invention obtains a lower lubrication coefficient, and favorable rheological property and thermostability, and is suitable for use in operation at a high temperature.

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The present invention relates to the well drilling field in petroleum industry, in particular to a nano-hybrid lubricant and method thereof, and oil-based drilling fluid. The lubricant comprises: graphite oxide and a biquaternary ammonium salt compound of which the cation part is represented by formula (1). The present invention also provides a method for preparation of the lubricant and an oil-based drilling fluid containing the lubricant. The lubricant provided in the present invention can be comprehended as a nano-hybrid material. Thus, oil-based drilling fluids that contain the lucbricant provided in the present invention have lower lubrication coefficient and excellent lubricating property without or with little negative impact on rheological property of the oil fluid, and the lubricant provided in the present invention has excellent thermostability thus suitable for use in operation at a high temperature.

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