Computer-assisted design of oil additives: hydrate and wax inhibitors

Abstract

In this paper we present the results of a molecular simulation study of low dosage anti-freeze agents for two common problems that occur during oil and gas transport: gas hydrate crystallization and wax deposition. Direct molecular dynamics simulations are presented of the nucleation and growth of methane hydrate from a liquid water film, and of the suppression of this growth in the presence of a well-known kinetic inhibitor—polyvinylpyrrolidone. In the case of wax inhibition we present a simple model for predicting the activity of comb-like polymers, which is likely to be useful for identifying the most active inhibitor from within a given class. The method is applied to a set of random copolymers and shown to correlate well with experimental data.