The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 18, 2020
Filed:
Nov. 20, 2018
Cnpc Engineering Technology R&d Company Limited, Beijing, CN;
China University of Petroleum (East China), Qingdao, CN;
Yuping Yang, Beijing, CN;
Jingping Liu, Qingdao, CN;
Long Li, Beijing, CN;
Dongyang Li, Beijing, CN;
Wei Zhang, Beijing, CN;
Lei Guo, Beijing, CN;
Lulu Li, Beijing, CN;
CNPC ENGINEERING TECHNOLOGY R&D COMPANY LIMITED, Beijing, CN;
CHINA UNIVERSITY OF PETROLEUM (EAST CHINA), Qingdao, CN;
Abstract
The present invention relates to the technical field of well drilling, and discloses a plugging agent for temperature-resistant calcium-resistant water-based drilling fluid used in oil and gas reservoir protection, a drilling fluid, and uses of the plugging agent and the drilling fluid. The plugging agent for temperature-resistant calcium-resistant water-based drilling fluid used in oil and gas reservoir protection contains acrylamide-diallyldimethylammonium chloride copolymer modified graphene, wherein in the acrylamide-diallyldimethylammonium chloride copolymer, a molar ratio of structural units provided by acrylamide to structural units provided by diallyldimethylammonium chloride is 1:5-15, and the number-average molecular weight of the acrylamide-diallyldimethylammonium chloride copolymer is 15,000-30,000. The water-based drilling fluid described in the present invention is especially applicable to well drilling in deep salt-gypsum formations, and can exhibit good filtrate reducing, plugging, temperature-resistant, anti-collapsing, and reservoir protection performance.