摘要:
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
摘要:
The present invention relates to the well drilling field in petroleum industry, in particular to a drilling fluid additive composition and a water-based drilling fluid suitable for high pressure plugging while drilling. The composition contains a bridging agent, a nano-plugging agent, a rheological modifier, a bionic wall bracing agent, and a bionic shale inhibitor, wherein, the bridging agent is a weak-crosslinked copolymer, in which the content of cross-linker structures is 0.1-1 wt. %; the nano-plugging agent is modified nanometer silicon dioxide particles; the rheological modifier is a dimer acid-organic amine copolymer; and the bionic wall bracing agent is carboxymethyl chitosan with a dopamine-derived base group grafted on its main chain. With a synergistic effect among the bridging agent, the nano-plugging agent, the rheological modifier, the bionic wall bracing agent, and the bionic shale inhibitor in the composition provided in the present invention, the water-based drilling fluid containing the composition as additive can attains an excellent plugging effect in a drilling process.
摘要:
The invention relates to the technical field of oil and gas drilling, and discloses an amphiphilic block polymer ultralow-permeability agent and an intelligent temporary plugging type water-based drilling fluid. The ultralow-permeability agent contains a structural unit provided by styryl hydrophobic monomer, maleic anhydride and acrylamide; the drilling fluid contains two or more of water, sodium bentonite, Pac-Lv, the ultralow-permeability agent, calcium carbonate, one-way plugging agent, white asphalt and barite which are stored in a mixed manner or independently stored. When the amphiphilic block polymer provided by the invention is used as the ultralow-permeability agent of the intelligent temporary plugging type water-based drilling fluid, the self-adaptive characteristic is realized; according to the amphiphilic block polymer, temporary plugging layer gaps formed in pore and throats by plugging materials in drilling fluid can be fully filled under the condition that the sizes and the distribution of the pore and throats of reservoirs are not required to be clear, so that the permeability of temporary plugging layer is greatly reduced, ultralow-permeability is realized, and the amphiphilic block polymer is weak in tackifying effect, has gel-improving effect and can improve the rheological property of the drilling fluid.
摘要:
The present invention relates to the well drilling field in petrochemical industry, in particular to use of dual-cation fluorocarbon surfactant as amphiphobic wettability reversal agent in drilling fluid. The dual-cation fluorocarbon surfactant is a dual-cation fluorocarbon surfactant of which the cation part is represented by the following formula (1). The dual-cation fluorocarbon surfactant of the present invention can serve as wettability reversal agent when it is used for oil-gas drilling to enable rock amphiphobic, and is an amphiphobic wettability reversal agent which can cause rock surface to be non-hydrophilic and non-lipophilic. Using of dual-cation fluorocarbon surfactant, especially when drilling highly hydrous mud shale, can avoid permeation of water and oil into the rock effectively and thereby a capillary phenomenon can be prevented, and an effect of stabilizing the well wall and protecting the reservoir is attained.
摘要:
The present invention relates to the well drilling field in petroleum industry, in particular to a drilling fluid additive composition suitable for coal-bed gas wells, and a water-based drilling fluid and use of the water-based drilling fluid. The drilling fluid additive composition suitable for coal-bed gas wells, comprising a tackifying and shear improver, a capsulating agent, a filtrate reducer, and an amphiphobic wettability reversal agent, wherein, the tackifying and shear improver is a copolymer comprising structural units represented by formula (1), structural units represented by formula (2), and structural units represented by formula (3); the capsulating agent is a comb-like polysaccharide compound; the filtrate reducer is nanocrystalline cellulose, and the amphiphobic wettability reversal agent is a dual-cation fluorocarbon surfactant. The composition provided in the present invention can be used as an additive in a solid-free brine drilling fluid, so that the brine drilling fluid obtains advantages of a high penetration rate and a low residue rate.
摘要:
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. When a clay-free oil-in-water drilling fluid contains the drilling fluid additive composition of the present invention containing the emulsifier and rheological modifier, it may have high temperature resistance and high density;
摘要:
The present invention relates to the technical field of oil and gas drilling, and discloses a biodiesel-based constant rheological property drilling fluid containing intelligent temperature responsive polymer, which contains two or more of the following components which are stored in admixture or separately: base oil biodiesel, aqueous phase, emulsifier, organic soil, constant rheological property flow pattern modifier, hydrolysis inhibitor, filtrate reducer and weighting material; the constant rheological property flow pattern modifier is an intelligent temperature responsive polymer, and the polymer contains structural units provided by bis-hydroxyethyl bis-hydroxypropyl stearyl ammonium chloride, ethylene bis-stearamide and dimerized fatty acid. The drilling fluid provided by the present invention has excellent environmental protection property and degradability, and has conventional rheological property, weak gel structure and fluid loss property which are equivalent to those of the conventional oil-based drilling fluid, and also has excellent temperature resistance, CaO compatibility and constant rheological property.
摘要:
The present disclosure relates to the technical field of water-based drilling fluid, in particular to a modified polyhistidine suitable for being used as a supramolecular shale inhibitor, a method of preparing the same, and its application in water-based drilling fluids. The modified polyhistidine has a histidine polymerization main chain comprising a structural unit, which is represented by Formula (1) and attached with a modifying group, and the histidine polymerization main chain has a histidine polymerization degree of 6-9. The modified polyhistidine provided by the present disclosure is a degradable biological material and has the advantage of environmental friendliness; when the modified polyhistidine is used as a shale inhibitor, it can take advantage of its supermolecular property to effectively inhibit the hydration expansion of montmorillonite which is the most important expansion mineral in shale, and exhibits excellent inhibition effect and desirable temperature resistance.
摘要:
The present invention relates to the well drilling field in petrochemical industry, and discloses a high-density water-based drilling fluid suitable for horizontal shale gas wells comprising a nano-plugging agent, a bionic wall bracing agent, a bionic shale inhibitor, a filler, an emulsifier, and an amphiphobic wettability reversal agent, wherein, the nano-plugging agent is modified silicon dioxide nano-particle, and its modifying group includes a modifying copolymer chain; the bionic wall bracing agent is carboxymethyl chitosan with a dopamine-derived group grafted on its main chain; the bionic shale inhibitor is composed of structural units of arginine and structural units of lysine; the filler consists of calcium carbonate of 1,600-2,500 mesh, calcium carbonate of 1,050-1,500 mesh, and calcium carbonate of 500-1,000 mesh at a weight ratio of 1:0.55-6:0.55-6; and the amphiphobic wettability reversal agent is a dual-cation fluorocarbon surfactant. The drilling fluid provided herein is suitable for use in shale gas mining.
摘要:
The present invention relates to the well drilling field in petroleum industry, in particular to an additive composition suitable for viscosity reduction of oil-based drilling fluids, an oil-based drilling fluid and use thereof. The double-block copolymer mainly consists of a block A and a block B, wherein, the block A is composed of structural units represented by formula (1), the block B is composed of structural units represented by formula (2), and the number-average molecular weight of the block A is 1,500-10,000. The double-block copolymer provided in the present invention can be used as a viscosity reducer in oil-based drilling fluids, especially can be used as a viscosity reducer in high-density clay-free oil-based drilling fluids, and can greatly decrease the apparent viscosity and plastic viscosity of oil-based drilling fluids in high-temperature and high-pressure reservoir while maintaining appropriate shearing force, so as to increase the drilling rate and reduce drilling difficulties.