Bionic and dual-phobic high-performance water-based drilling fluid

Patent metadata

Field	Value
Publication number	US-11787990-B2
Application number	US-202218148939-A
Country	US
Kind code	B2
Filing date	Dec 30, 2022
Priority date	Aug 26, 2020
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

The present invention relates to the field of petroleum industry phase oilfield chemistry, and specifically relates to a bionic and dual-phobic drilling fluid. The drilling fluid contains a bionic wall-fixing agent, a bionic lubricant, a super dual-phobic agent, a scrap-carrying agent and a bionic shale inhibitor. The present invention uses the theory of bionics and the theory of a downhole rock surface being double phobic as a basis. By means of using the bionic wall-fixing agent, the bionic lubricant, the super dual-phobic agent, the scrap-carrying agent and the bionic shale inhibitor, which have special properties of imitating animals and plants in nature, and using a series of bionic treatment agents, a set of bionic and dual-phobic drilling fluid systems, which corresponds to an unconventional, complex oil and gas well, is formed.

First claim

The invention claimed is:

1. A bionic and dual-phobic drilling fluid, wherein the drilling fluid comprising a bionic wall-fixing agent, a bionic lubricant, a super dual-phobic agent, a scrap-carrying agent and a bionic shale inhibitor;
the bionic wall-fixing agent is an acrylamide polymer containing a structural unit shown in a formula (1-a), a structural unit shown in a formula (2-a), a structural unit shown in a formula (3-a) and a structural unit shown in a formula (4-a), wherein the molar ratio of the structural unit shown in the formula (1-a), the structural unit shown in the formula (2-a), the structural unit shown in the formula (3-a) and the structural unit shown in the formula (4-a) is 1:(1.05-3):(0.5-0.95):(0.2-0.9);

wherein R 1 -R 7 , R 10 -R 12 and R 13 -R 15 are each independently selected from H and C1-C6 alkyl; R 8 -R 9 and R 16 are selected from alkyl groups of C1-C8; M is selected from H or alkali metal elements; L 1 and L 2 are each independently selected from the group consisting of C0-C6 alkylene;
the bionic lubricant is a block polymer, and the block polymer comprises a block A containing a carboxylic ester structural unit and a benzene-containing structural unit, and a block B containing an acrylamide structural unit connected with the block A; the benzene-containing structural unit is a structural unit shown in a formula (1-b); the carboxylic ester structural unit is one or more of structural units shown in formulas (2-b) and (3-b); the acrylamide structural unit is a structural unit shown in a formula (4-b);

wherein R 1 ′-R 2 ′, R 4 ′-R 6 ′, R 8 ′-R 10 ′ and R 12 ′-R 14 ′ are each independently selected from H and C1-C6 alkyl; L 1 ′ is selected from C0-C6 alkylene; R 7 ′ and R 11 ′ are selected from C1-C8 alkyl; R 15 ′ is selected from H, C1-C8 alkyl, -L 2 ′-SOOM′, L 2 ′ is selected from alkylene of C1-C6, and M′ is H or alkali metal element; R 3 ′ is selected from H, C1-C6 alkyl, phenyl or phenyl-substituted alkyl of C1-C6;
the super dual-phobic agent is a modified carbon nanotube with a modifying group on the surface, wherein the modifying group comprises a modifying group provided by a silane coupling agent containing unsaturated carbon-carbon double bonds, perfluorosulfonyl halide represented by a formula R 1 SO 2 X and siloxane represented by a formula R 3 Si(OR 2 ) 3 ; wherein R 1 is perfluoro-substituted alkyl of C4-C12, X represents halogen; R 3 is selected from alkyl of C1-C6 and alkoxy of C1-C6, R 2 is selected from alkyl of C1-C6;
the scrap-carrying agent is an Al 2 O 3 /SiO 2 composite material, and the composite material comprises solid particles containing Al 2 O 3 and SiO 2 , and a polyacrylamide polymer modified on the surfaces of the solid particles; wherein the polyacrylamide polymer contains structural units shown in a formula (1-c) and a formula (2-c):

wherein, R 1 ″-R 6 ″ are each independently selected from H or C1-C6 alkyl; L″ is selected from C0-C6 alkylene; R 7 ″ is selected from C6-C20 alkyl substituted by halogen;
the bionic shale inhibitor is modified chitosan, and the modified chitosan is connected with a modifying group with a structure shown in a formula (1-d); formula (1-d): —CH 2 —CH(OH)CH 2 -polyamine structure; and the polyamine structure is provided by polyamine compounds.

2. The drilling fluid according to claim 1 , wherein in the bionic wall-fixing agent, the molar ratio of the structural unit shown in the formula (1-a), the structural unit shown in the formula (2-a), the structural unit shown in the formula (3-a), the structural unit shown in the formula (4-a) is 1:(1.1-2):(0.6-0.95):(0.5-0.9),
the weight average molecular weight of the polymer as the bionic wall-fixing agent is 80000-250000 g/mol, preferably 95000-220000 g/mol;
R 1 -R 7 , R 10 -R 12 and R 13 -R 15 are each independently selected from H and C1-C4 alkyl; R 8 -R 9 and R 16 are selected from alkyl groups of C1-C6; M is selected from H, Na or K; L 1 and L 2 are each independently selected from the group consisting of C0-C4 alkylene.

3. The drilling fluid according to claim 1 , wherein R 1 -R 7 , R 10 -R 12 and R 13 -R 15 are each independently selected from H, methyl, ethyl or n-propyl; R 8 -R 9 and R 16 are selected from methyl, ethyl, n-propyl, isopropyl, n-butyl or isobutyl; M is selected from H, Na or K; L 1 and L 2 are each independently absent, —CH 2 —, —CH 2 CH 2 —, —CH 2 CH 2 CH 2 — or —CH 2 CH 2 CH 2 CH 2 —.

4. The drilling fluid according to claim 1 , wherein the structural unit represented by formula (1-a) is provided by acrylamide and/or methacrylamide; the structural unit represented by the formula (2-a) is provided by one or more of dimethyldiallylammonium chloride, dimethyldiallylammonium fluoride, diethyldiallylammonium chloride, diethyldiallylammonium fluoride, dimethyldi (2-alkenylbutyl) ammonium chloride, dimethyldi (2-alkenylbutyl) ammonium fluoride, diethyldi (2-alkenylbutyl) ammonium chloride and diethyldi (2-alkenylbutyl) ammonium fluoride; the structural unit shown in the formula (3-a) is provided by one or more of acrylic acid, methacrylic acid, 2-butenoic acid, sodium acrylate, sodium methacrylate and sodium 2-butenoate; the structural unit represented by the formula (4-a) is provided by one or more of vinyl acetate, vinyl n-propionate, isopropenyl acetate, isopropenyl n-propionate, propenyl acetate and propenyl n-propionate.

5. The drilling fluid according to claim 1 , wherein in the bionic lubricant, the molar ratio of the benzene-containing structural units, the carboxylic ester structural units and acrylamide structural units is (2-10): 1:(0.01-0.8);
the block A is a random copolymer block consisting of a benzene-containing structural unit and a carboxylic ester structural unit, or is a two-block polymer block consisting of a block A1 consisting of a benzene-containing structural unit and a block A2 consisting of a carboxylic ester structural unit;
the weight average molecular weight of the block polymer as the bionic lubricant is 10000-50000 g/mol, preferably 12000-40000 g/mol;
R 1 ′-R 2 ′, R 4 ′-R 6 ′, R 8 ′-R 10 ′ and are each independently selected from H and C1-C4 alkyl; L 1 ′ is selected from C0-C4 alkylene; R 7 ′ and R 11 ′ are each independently selected from the group consisting of C1-C6 alkyl; R 15 ′ is selected from H, C1-C6 alkyl or -L 2 ′-SOOM′, L 2 ′ is selected from alkylene of C1-C6, and M′ is H, Na or K; R 3 ′ is selected from H, C1-C4 alkyl, phenyl or phenyl-substituted alkyl of C1-C4.

6. The drilling fluid according to claim 1 , wherein R 1 ′-R 2 ′, R 4 ′-R 6 ′, R 8 ′-R 10 ′ and R 12 ′-R 14 ′ are each independently selected from H, methyl, ethyl or n-propyl; L 1 ′ is absent, —CH 2 —, —CH 2 CH 2 —, —CH 2 CH 2 CH 2 — or —CH 2 CH 2 CH 2 CH 2 —; R 7 ′ and R 11 ′ are each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl or isobutyl; R 15 ′ is selected from H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, —CH 2 -SOOM′, —CH 2 CH 2 -SOOM′, —CH 2 CH 2 CH 2 -SOOM′, —CH(CH 3 )CH 2 -SOOM′, —CH 2 CH(CH 3 )—SOOM′, —C(CH 3 ) 2 —SOOM′, —CH 2 CH 2 CH 2 CH 2 -SOOM′, —CH(CH 3 )CH 2 CH 2 -SOOM′, —CH 2 CH(CH 3 )CH 2 -SOOM′, —CH 2 CH 2 CH(CH 3 )—SOOM′, —C(CH 3 ) 2 CH 2 -SOOM′ or —CH 2 C(CH 3 ) 2 —SOOM′, M′ is H, Na or K; R 3 ′ is selected from H, methyl, ethyl, n-propyl, phenyl or benzyl.

7. The drilling fluid according to claim 1 , wherein the benzene-containing structural unit is provided by a compound selected fro

Assignees

• Univ China Petroleum Beijing
• Cnpc Chuanqing Drilling Eng Co
• Cnpc Eng Tech Res & Dev Co Ltd

Inventors

• Jiang Guancheng
• Sun Jinsheng
• He Yinbo
• Zhang Xin
• Peng Chunyao
• Dong tengfei
• Tan Bin
• Geng Tie
• Yang Lili
• Luo Xiaohu
• Luo Xuwu
• Liang Xing
• Chen Changwei
• Liu Xiaobo
• Cheng Rongchao
• Luo Jiansheng
• Zhang Jianguo
• Wang Yong
• Fu Daqi
• Ran Qifa
• Zhao Li
• Cui Kaixiao
• Ni Xiaoxiao

Classifications

• C09K8/24 Primary

  Polymers · CPC title

• C09K8/16

  characterised by the inorganic compounds other than clay · CPC title

• C09K8/206

  Derivatives of other natural products, e.g. cellulose, starch, sugars · CPC title

• C09K2208/10

  Nanoparticle-containing well treatment fluids · CPC title

• C09K2208/12

  Swell inhibition, i.e. using additives to drilling or well treatment fluids for inhibiting clay or shale swelling or disintegrating · CPC title