| abstract |
A method for inhibiting the formation of clathrate hydrates in a fluid (e.g. natural gas) having hydrate-forming constituents is disclosed. The hydrate inhibitors used in the method are substantially water soluble polymers formed from an N-substituted acrylamide having two nitrogen substituent groups, R1 and R2, where R1 is a hydrocarbon group having from one to ten carbon atoms and zero to four heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur, and combinations thereof, and R2 is a hydrogen atom or a hydrocarbon group having from one to ten carbon atoms and zero to four heteroatoms selected from the group consisting of carbon, nitrogen, oxygen, and sulfur. Alternatively, R1 and R2 may be linked to produce a cyclic ring having ten atoms comprising a combination of between three and ten carbon atoms and zero to four heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur, and combinations thereof. Some examples of such inhibitors include poly(N-ethylacrylamide), poly(N,N-diethylacrylamide), poly(N-methyl, N-acrylamide), poly(iso-propylacrylamide), poly(N-propylacrylamide), poly(N-cyclopentylacrylamide), poly(N-cyclohexylacrylamide), poly(acryloylpyrrolidine), poly(acryloylpiperidine), poly(acryloylmorpholine) and various N-substituted acrylamide copolymers. |