Water based alkyl ethoxylate drilling fluid

摘要

A water based drilling fluid contains as an additive one or more alkyl ethoxylates having the formula RO(CH2CH20)nH; wherein: R is a C16-22 alkylgroup (preferably R is aliphatic and more preferably R is linear), and n is an integer in the range 2-30. The fluid also contains a viscosifying agent and is substantially clay-free. The fluid can be used in shale inhibition.