A Critical Review of Controlling Paraffin Deposition in Production Lines Using Chemicals

Wax deposition in oil and gas pipelines is considered one of the most severe operational problems, and significant efforts have been made to prevent and remediate this flow assurance issue. Chemical wax control strategies have received considerable attention, especially in certain cases where applying the mechanical and thermal treatment is inconvenient and difficult. However, until now expensive and inefficient "trial-and-error" procedures were used in fields, possibly due to the lack of the fundamental understanding of how these chemicals work in different operating conditions. Here, a comprehensive review of the available literature on chemical wax control strategies is presented. The key performance parameters used in assessing the chemicals in the laboratory are systematically reported. All commonly used wax inhibitors, pour point depressants, and wax dispersants are described based on the types, affecting factors, working mechanisms, and testing facilities. Solvents that are used to dissolve the wax deposits or to reduce the viscosity of the fluid are also discussed. Finally, future challenges ahead for chemical wax control research are discussed.