Paraffin Wax Deposition and Remediation Techniques in Crude Oil System: A Review

Abstract

Paraffin wax deposition is the major flow assurance issue in the oil industry. When the fluid temperature drops below the wax appearance temperature (WAT) due to the temperature differential between the cold areas and the crude oil, paraffin wax forms on the pipeline walls. Wax deposition can have very detrimental effects because it can narrow the internal diameters of pipelines and flowlines, which, if left unchecked, eventually clog these areas and force an activity to stop. However, overcoming the problems at this stage may become very expensive. This study examines the factors influencing paraffin wax deposition and discusses various methods for mitigating wax deposition on inner pipelines walls. It focuses on mechanical, thermal, chemical, bioremediation, and hybrid techniques. The benefits and limitations of each wax mitigation technique are assessed, along with the latest developments in modelling-based paraffin wax deposition mitigation. Although chemical techniques are preferable for treating deep-water wells due to their relatively inexpensiveness, simplicity, and no disruption to production, synthetic chemical inhibitors pose environmental hazardous. However, the advantages of organic chemical additives and bioremediation technique over commercially available synthetic chemical inhibitors are rigorously assessed in this work with regard to environmental benefits, sustainability advantages and improved process safety. This review also identifies the gaps in mitigation of paraffin wax deposition.