Process for inhibition of sulphide scales

Abstract

The invention provides for the use of a copolymer, comprising a) 0.1 to 10 mol-%, based on the weight of the copolymer, of structural units derived from vinylphosphonic acid or of a salt thereof, b) 40 to 80 mol-%, based on the weight of the copolymer, of structural units derived from compounds of the formula (1) c) 1 to 50 mol-%, based on the weight of the copolymer, of structural units derived from compounds of the formula (5) in which X is OH or NR3R4, and R3 and R4, independently of one another, are H or C1-C4-alkyl, for the inhibition and/or dispersion of inorganic sulphide scales, and for a process for the inhibition and/or dispersion of inorganic sulphide scales, the process comprising adding to water being within an oil or gas containing formation said copolymer.

Dependencies are inferred from the claim text.