Treatment of oil

Abstract

A method of treating crude oil which comprises contacting the oil with a treatment fluid formulation comprising a polymeric material which comprises vinylalcohol repeat units, wherein said polymeric material is of a type which has a weight average molecular weight in the range 5,000 to 50,000 and/or wherein the viscosity of a 4 wt % aqueous solution of the polymeric material at 2° C. is in the range 1.5-7 cP. The oil may be contacted with the treatment fluid formulation underground by, for example, injection of the fluid formulation into an injection well or production well and the mobility of the oil contacted thereby is significantly improved.

Dependencies are inferred from the claim text.