Abstract: Disclosed is a bio-enzyme degradable temporary plugging material and a preparation method and application thereof in the technical field of natural gas hydrate drilling and production; the preparation method of the bio-enzyme degradable temporary plugging material includes the following steps: mixing the ceramsite with an aqueous solution of 3-aminopropyl trimethoxysilane before a stirring reaction and drying to obtain modified ceramsite; and fully dispersing the modified ceramsite, ethyl cellulose, and epoxy resin in dichloromethane to obtain an oil phase; adding the oil phase into a gelatin aqueous solution and mixing uniformly; after a stirring reaction, evaporating an organic solvent, filtering, washing, and drying, to obtain the bio-enzyme degradable temporary plugging material.

Abstract: A method for preparing low-background cement includes: uniformly mixing a seed crystal of cement, C4AF whiskers, and high-magnesium raw material to yield a first mixture, calcining the first mixture at 1400-1500° C., to yield a low-background clinker, the first mixture including 1.0-5.0 wt. % of the seed crystal of cement, 1.0-5.0 wt. % of the C4AF whiskers, and the balance is the high-magnesium raw material; and grinding a second mixture of the low-background clinker and gypsum, to yield low-background cement. The seed crystal of cement is a high-magnesium and low hydration heat clinker, has a specific activity of Ra-226 radioactive nuclides within 50 Bq/kg, and the MgO content of the clinker is between 4.0 wt. % and 5.0 wt. %, with 50 wt. %?C3S?55.0 wt. %; and the high-magnesium raw material has a MgO content between 2.5 wt. % and 3.0 wt. %.

Abstract: An oil-soluble thermosensitive resin lost circulation material for protecting a reservoir includes the following raw materials in parts by weight: 40-60 parts of resin matrix, 15-40 parts of modified asphalt, 5-12 parts of viscosity modifier, 2-5 parts of cross-linking agent, 6-15 parts of softening point modifier, and 1-3 parts of dispersant; it further provides a method for preparing the resin lost circulation material; the resin lost circulation material can melt and adhere in different temperature ranges, rapid plugging is realized, and the plugging time is long; the oil-soluble thermosensitive resin lost circulation material can be dissolved by oil flow during oil well production, so that the reservoir permeability is recovered, so as to achieve the purpose of protecting the hydrocarbon reservoir.

Abstract: A high temperature and high salinity-resistant complementarily rigid-flexible plugging agent, a method for preparing the same, and a water-based drilling fluid and a use thereof.

Abstract: A high temperature and high salinity-resistant complementarily rigid-flexible plugging agent, a method for preparing the same, and a water-based drilling fluid and a use thereof.

Abstract: A nano-organosilicon film-forming and hydrophobic shale surface hydration inhibitor is obtained by performing hydrophobic modification for nano-particles through long-chain organosilicon together with a surface-active agent. A preparation method of the said hydrophobic shale surface hydration inhibitor comprises steps as follows: nano-particles are added to the solvent under stirring conditions, and then an ultrasonic dispersion is performed; upon the end of the ultrasonic dispersion, the reaction system is adjusted to a pH of 9-11 to obtain mixed solution A; a long-chain organosilicon solution is then dropwise added to the mixed solution A for reaction under stirring conditions to obtain mixed solution B; a surface-active agent is added to the mixed solution B for reaction under stirring conditions; upon the reaction is finished, part of the solvent is removed to obtain the inhibitor.

Abstract: An oil-soluble thermosensitive resin lost circulation material for protecting a reservoir includes the following raw materials in parts by weight: 40-60 parts of resin matrix, 15-40 parts of modified asphalt, 5-12 parts of viscosity modifier, 2-5 parts of cross-linking agent, 6-15 parts of softening point modifier, and 1-3 parts of dispersant; it further provides a method for preparing the resin lost circulation material; the resin lost circulation material can melt and adhere in different temperature ranges, rapid plugging is realized, and the plugging time is long; the oil-soluble thermosensitive resin lost circulation material can be dissolved by oil flow during oil well production, so that the reservoir permeability is recovered, so as to achieve the purpose of protecting the hydrocarbon reservoir.

Abstract: The present disclosure to a cementitious plugging wall solidifier for water-based drilling fluid and a preparation method thereof and a water-based drilling fluid.

Abstract: The present disclosure relates to the technical field of oilfield chemistry. A flocculating agent for removing oil-based drilling fluid rock cuttings and a preparation method and a use thereof.

Abstract: The present discloses a water-based gel-consolidation type lost circulation material system suitable for fractured lost circulation formation, preparation method and use thereof.

Abstract: A high-temperature resistant, high-strength, and thixotropic gel plugging agent is composed of 8-20% of acrylamide monomer, 0.05-0.5% of reactive polymer, 0.1-1.0% of organic polymer cross-linker, 3.0-8.0% of resin toughening agent, 1.0-5.0% of flow pattern regulator, 0.01-0.5% of cross-linking regulator by the weight in the water. The gel solution shows a low apparent viscosity during the shear flow and is easy to be pumped into the wellbore and then into the formation leakage layer; after the pumping stops, the gel solution shows rapidly increased viscosity and strong adhesive force, and form a high-strength barrier between the wellbore and the formation, preventing the drilling fluid from further leaking.

Abstract: A nano-organosilicon film-forming and hydrophobic shale surface hydration inhibitor is obtained by performing hydrophobic modification for nano-particles through long-chain organosilicon together with a surface-active agent. A preparation method of the said hydrophobic shale surface hydration inhibitor comprises steps as follows: nano-particles are added to the solvent under stirring conditions, and then an ultrasonic dispersion is performed; upon the end of the ultrasonic dispersion, the reaction system is adjusted to a pH of 9-11 to obtain mixed solution A; a long-chain organosilicon solution is then dropwise added to the mixed solution A for reaction under stirring conditions to obtain mixed solution B; a surface-active agent is added to the mixed solution B for reaction under stirring conditions; upon the reaction is finished, part of the solvent is removed to obtain the inhibitor.

Abstract: A high temperature-resistant and high oil-absorption resin particle plugging agent suitable for oil-based drilling fluid and its preparation method is prepared from raw materials in parts by mass as follows: 15-30 parts of reaction monomers, 5-12 parts of linear high polymers, 0.1-1.5 parts of cross-linking agents, 0.1-0.5 parts of initiators, 1-3 parts of modified starches, 1-5 parts of filler particles and 1-5 parts of dispersing agents; it has high oil absorption capacity under a high-temperature condition and high toughness after oil-absorbing expansion.

Abstract: The present disclosure provides a preparation method of an environment-friendly high-temperature resistant water-based drilling fluid plugging anti-sloughing agent, the preparation method comprises the following steps: mixing and emulsifying a styrene monomer, an acrylic monomer and an emulsifier MS-1 aqueous solution to prepare a pre-polymerization emulsion; dispersing hydrophilic monomer, cationic monomer and an emulsifier MS-1 in water, adjusting the pH to be within a range of 6.5-8.

Abstract: The present disclosure provides a preparation method of an environment-friendly high-temperature resistant water-based drilling fluid plugging anti-sloughing agent, the preparation method comprises the following steps: mixing and emulsifying a styrene monomer, an acrylic monomer and an emulsifier MS-1 aqueous solution to prepare a pre-polymerization emulsion; dispersing hydrophilic monomer, cationic monomer and an emulsifier MS-1 in water, adjusting the pH to be within a range of 6.5-8.

Abstract: The invention discloses a calcium-resistant zwitterionic polymer, a preparation method and an application thereof, and a water-based drilling fluid containing the polymer as a dispersing agent, wherein the polymer contains a structural unit A, a structural unit B and a structural unit C, and the structural unit A is at least one selected from the group consisting of structural units with a structure shown in a formula (11), a structure shown in a formula (12) and a structure shown in a formula (13); the structural unit B is a structural unit with a structure shown in a formula (2); the structural unit C is at least one selected from the group consisting of structural units having a structure represented by formula (31) and a structure represented by formula (32); the weight-average molecular weight of the polymer is 350,000 to 600,000.

Abstract: The invention presents a high temperature-resistant and high oil-absorption resin particle plugging agent suitable for oil-based drilling fluid and its preparation method, wherein the plugging agent is prepared from raw materials in parts by mass as follows: 15-30 parts of reaction monomers, 5-12 parts of linear high polymers, 0.1-1.5 parts of cross-linking agents, 0.1-0.5 parts of initiators, 1-3 parts of modified starches, 1-5 parts of filler particles and 1-5 parts of dispersing agents. The resin particle plugging agent presented in the invention not only has high oil absorption capacity under a high-temperature condition, but also has high toughness after oil-absorbing expansion. It is not easy to break by extrusion and stretching and can effectively plug a high-temperature leakage passage. Also, the resin plugging particles in it will not be affected by crack factors.

Abstract: The invention provides a high-temperature resistant, high-strength, and thixotropic gel plugging agent and its preparation method and application. The said gel plugging agent is composed of raw materials in the following mass percent: 8-20% acrylamide monomer, 0.05-0.5% reactive polymer, 0.1-1.0% organic polymer cross-linker, 3.0-8.0% resin toughening agent, 1.0-5.0% flow pattern regulator, 0.01-0.5% cross-linking regulator, and water in the remaining percentage.

Abstract: The present disclosure relates to the technical field of oil and gas drilling, and particularly relates to a modified silicon dioxide material of a fluorocarbon active agent type super-amphiphobic cutting-carrying agent suitable for a water-based drilling fluid, and a preparation method thereof. The preparation method of the modified silicon dioxide material comprises the following steps: subjecting silicon dioxide and a silane coupling agent represented by Formula (1) to a first contact reaction in a mixed solvent containing alcohol and water; subjecting the product of the first contact reaction, the compound represented by Formula (2) and the compound represented by Formula (3) to a second contact reaction; subjecting the product of the second contact reaction and the compound represented by Formula (4) to a third contact reaction. The modified silicon dioxide material can be used as a cutting-carrying agent in a water-based drilling fluid and produce an excellent cutting-carrying effect.

Abstract: The present invention relates to the field of petrochemical drilling and discloses a drilling fluid additive composition. The composition contains an emulsifier and a rheological modifier. The emulsifier is one or more of the compounds represented by Formula (1); the rheological modifier is dimer acid-organic amine copolymer, comprising structural units from the dimer acid, structural units from the alkylamine and structural units from the arylamine. The present invention further provides a drilling fluid containing the foregoing composition.