Shale inhibitor and preparation method thereof, water-based drilling fluid, and shale gas drilling and extraction method

US10287475B1 · kind B1 · utility

Assignee

• Southwest Petroleum University · CN

Inventors

• Xiaolin Pu · Chengdu, CN
• Hao Wang · Gatineau, CA

Key dates

• Filing date: Jul 24, 2018
• Grant date: May 14, 2019
• Expiry date: Jul 24, 2038

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K2208/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to the field of shale inhibitors for drilling fluids, and discloses a shale inhibitor, a method for producing the shale inhibitor, a water-based drilling fluid, and a shale gas drilling and extraction method, wherein, the shale inhibitor contains structural units A represented by formula (I), optional structural units B represented by formula (II) and structural units C represented by formula (VIII), where, n is an integer within a range of 0-3; the shale inhibitor is an amino-terminated hyperbranched polymer; the quantity ratio of the structural units A to the structural units B to the structural units C is m:(m−1):(2m+2), wherein m is an integer within a range of 1-10. With the amino-terminated hyperbranched polymer inhibitor, the shale hydration inhibiting capability can be improved, and thereby the overall inhibition performance of a drilling fluid can be improved;