China University of Petroleum

Gang Qu

Li Li Zhao

Guancheng Jiang

Lili Yang

Yinbo He

Fan Liu

Deli Gao

Guangchang Ma

Xianmin Zhang

Xianzhu Wu

Haifang Sun

Liexiang Han

Junbin Chen

Jienian Yan

Wei Ou'Yang

Kai Wang

Chunlei Wang

Chunyao Peng

Zhengqiang Deng

Shuanglei Peng

Xinliang Li

Yawei Shi

Li Zhao

The present invention relates to the well drilling field in petrochemical industry, and discloses a drilling fluid additive composition comprising a nano-plugging agent, a bionic wall bracing agent, a bionic shale inhibitor, 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; and the amphiphobic wettability reversal agent is a dual-cation fluorocarbon surfactant. The present invention further provides a pseudo oil-based drilling fluid suitable for horizontal shale gas wells containing the above composition. When the water-based drilling fluid contains the drilling fluid additive composition provided in the present invention, the water-based drilling fluid would have high temperature-resistance, high plugging and high inhibition performance, is environment friendly, especially have high density, and is especially suitable for horizontal shale gas well mining.

Drilling fluid additive composition and pseudo oil-based drilling fluid suitable for horizontal shale gas wells

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.

High-density water-based drilling fluid suitable for horizontal shale gas wells

The present invention relates to the well drilling field in petrochemical industry, and discloses a drilling fluid additive composition and water-based drilling fluid suitable for horizontal shale gas wells. The composition comprises a nano-plugging agent, a bionic wall bracing agent, a bionic shale inhibitor, an emulsifier, and an amphiphobic wettability reversal agent, wherein, the nano-plugging agent is modified silicon dioxide nano-particles, and its modifying group includes an acrylic 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; and the amphiphobic wettability reversal agent is a dual-cation fluorocarbon surfactant. The drilling fluid containing the additive composition provided in the present invention has high temperature-resistance, high plugging and high inhibition performance, is environment friendly, especially has high density, and is applicable to shale gas mining.

Drilling fluid additive composition and water-based drilling fluid suitable for horizontal shale gas wells

The present invention relates to the well drilling field in petrochemical industry, and discloses an environment-friendly water-based drilling fluid applicable to 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 an acrylic 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 in the present invention has high temperature-resistance, high plugging and high inhibition performance, is environment friendly, especially has high density, and is applicable to shale gas mining.

Environment-friendly water-based drilling fluid applicable to horizontal shale gas wells

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. 

Additive composition suitable for viscosity reduction of oil-based drilling fluid, oil-based drilling fluid and use thereof

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Beijing, China

Gang Qu