China University of Petroleum

China University of Geosciences (beijing)

Beijing Shida Bocheng Technology Co., Ltd

He Shi

Guancheng Jiang

Lili Yang

Yinbo He

Tengfei Dong

Kai Wang

Chunyao Peng

Bin Tan

Kaixiao Cui

Yong Wang

Yong Qin

Fan Liu

Jun Cai

Guangchang Ma

Haifang Sun

Xuwu Luo

Xiaohu Quan

Yuxiu An

Rongchao Cheng

Xing Liang

Jianguo Zhang

Yawei Shi

Qingying Ge

Jienian Yan

Zhiliang You

Tie Geng

Wuquan Li

Xiaoqing Li

Jiansheng Luo

Chunlin Xie

Dongmin Jia

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.

Amphiphilic block polymer ultralow-permeability agent and intelligent temporary plugging type water-based drilling fluid

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.

Biodiesel-based constant rheological property drilling fluid containing intelligent temperature responsive polymer

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. 

Modified polyhistidine suitable for being used as a supramolecular shale inhibitor, method of preparing the same and its application in water-based drilling fluids

The present invention relates to the petroleum drilling fluid field, and discloses a modified silicon dioxide nano-particle comprising a modifying polymer chain composed of structural units provided by one or more of monomers represented by the following formula (1) and one or more of monomers represented by the following formula (2). The present invention provides a method for preparing modified silicon dioxide nano-particles and a drilling fluid suitable for shale gas wells containing the modified silicon dioxide nano-particles as a plugging agent. When the modified silicon dioxide nano-particles provided in the present invention are used as a plugging agent in a drilling fluid, they will not agglomerate into large-size particles, and can achieve a good plugging effect. 

Modified silicon dioxide nano-particles and preparation method thereof, and drilling fluid suitable for shale gas wells

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Beijing, China

He Shi