Clay and shale inhibition agents and method of use

摘要

The hydration of clays and shale in drilling operations may be inhibited by employing an aqueous based drilling fluid comprising a shale hydration inhibition agent having the formula: (I), R is an alkyl group having 1 to 6 carbons; R1 may be the same or different than R and is an alkyl group having 1 to 10 carbons or a hydroxy alkyl group comprising n number of carbons wherein n is an integer from 1 to 10 and n−1 hydroxyl groups; R2 is an alkyl group having 1 to 6 carbons; R3 may be the same or different than R2 and is an alkyl group having 1 to 10 carbons or a hydroxy alkyl group comprising n number of carbons wherein n is an integer from 1 to 10 and n−1 hydroxyl groups, with the proviso that R3 is not the same as R1; and X is an anion. The shale hydration inhibition agent should be present in the aqueous based drilling fluid in sufficient concentration to reduce the reactivity, such as swelling, of clays and shale when exposed to water-based drilling fluids.;

主权项

1. An aqueous based drilling fluid composition comprising:
i) an aqueous based continuous phase; ii) a reactive clay or shale material; and iii) a shale hydration inhibition agent having the formula: R is —CH3; R1 is —CH3; R2 is —CH3; R3 is —CH2CH2OH; —CH(CH2OH)2; or; —C(CH2OH)3; and X is chloride; wherein the shale hydration inhibition agent is present in sufficient concentration to reduce the reactivity of the clay or shale.