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Summary Pigging technology is the most common and cost-effective method for wax deposition remediation, but the inability to accurately predict the pigging parameters during the field pigging process causes pipe plugging incidents to occur from time to time. This study developed a theoretical model that incorporates the rheomalaxis elastoviscoplasticity (REVP) of the wax deposit. The concepts of dynamic and static yield stresses were introduced to determine the maximum shear stress in two shear states. The proposed model can accurately estimate the wax breaking force (WBF) and the wax removal efficiency (WRE) under various pigging conditions, according to the experimental results and published data. In addition, the indoor pigging experiments revealed for the first time that a higher pigging speed could increase the WBF while reducing the WRE of the disk pig. The model interpreted these experimental results as a consequence of the rheological behavior of the wax deposit (i.e., the increase in the ramp rate of the shear rate leads to higher dynamic yield stress). Introduction Flow assurance involves a series of maintenance strategies and operational measures arising from the transport of hydrocarbon fluids in pipelines (Jamaluddin and Kabir 2012). During pipeline transport of hydrocarbon fluids, changes in operating pressure and temperature or unplanned pipeline shutdowns can lead to a number of challenging flow assurance issues, including asphaltene deposition (Hassanpouryouzband et al. 2018), gas hydrate formation (Hassanpouryouzband et al. 2020), waxy crude oil gelation (Bao and Zhang 2020), and wax deposition (Van der Geest et al. 2021). When waxy crude oil is exploited from deepwater strata, the reservoir temperature is so high that n-alkanes can be present in the waxy crude oil in a molecular state. However, the low seawater temperatures surrounding the subsea pipelines will inevitably cause the oil temperature to fall below the wax appearance temperature of the waxy oil, resulting in the crystallization of paraffin from the solvent (Van der Geest et al. 2021).
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