China University of Petroleum

Yongqing Zhang

Guancheng Jiang

Yinbo He

Lili Yang

Deli Gao

Fan Liu

Chunyao Peng

Shuo Zhang

Yong Wang

Zhong Xian Li

Chong Liu

Lin Cheng

Xianzhu Wu

Haifang Sun

Liexiang Han

Yanjun Li

Zhaohui Wang

Qingying Ge

Xiangzeng Wang

Hongguo Zuo

Jingdong Hu

Xi Wang

Yong Qin

Guangchang Ma

The present invention relates to well drilling field in the petroleum industry, particularly to accelerator used for drilling fluids, water-based drilling fluid and usage thereof. The accelerator contains: sulfonated polyglycerol long-chain fatty acid ester, fatty alcohol polyoxyethylene ether, alcohol ether carboxylate, glycidyl ether, and polyoxyethylene alkylphenol ether; wherein, the weight ratio of the sulfonated polyglycerol long-chain fatty acid ester:the fatty alcohol polyoxyethylene ether:the alcohol ether carboxylate:the glycidyl ether:the polyoxyethylene alkylphenol ether is 100:1-10:0.5-10:1-10:1-10. The accelerator provided in the present invention can lubricate the drill bit and drilling tool, prevent accumulation of drill cuttings, reduce friction, and improve rate of penetrate.

Accelerator used for drilling fluids, water-based drilling fluid and usage thereof

The present invention relates to the well drilling field in the petroleum industry, particularly to film former used for coal-bed gas well drilling and preparation method thereof, drilling fluid and usage thereof. The preparation method of the film former includes: (1) controlling polycaprolactone diol and diisocyanate to have a first polymerization reaction in the presence of a polyurethane catalyst, to obtain a polyurethane prepolymer with two ends blocked by diisocyanate; (2) controlling the product of the first polymerization reaction to have a chain extension reaction with a polyalcohol; (3) controlling the product of the chain extension reaction and one part of hydroxyalkyl acrylate monomer to have an additive reaction, and then introducing the other part of hydroxyalkyl acrylate monomer and a styrene monomer, and emulsifying in water to obtain an emulsion; (4) mixing a radical initiator with the emulsion to have a second polymerization reaction.

Film former used for coal-bed gas well drilling and preparation method thereof, drilling fluid and usage thereof

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. 

Drilling fluid additive composition suitable for coal-bed gas wells, and water-based drilling fluid and use thereof

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.

Drilling fluid additive composition and water-based drilling fluid suitable for high-pressure plugging

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Beijing, China

Yongqing Zhang