Prediction for wax deposition in oil pipelines validated by field pigging

The deposition of wax in oil pipelines presents a costly production and transportation problem. The deposited wax is removed periodically by pigging operation in field. In this study, in order to understand this problem and address it, a series of wax deposition experiments involved the sloughing effect was performed in the laboratory flow loop, and a model was established to predict the wax deposition distribution along the pipeline. These results were used to implement a pigging program. In addition, a practical experimental method by testing the viscosity of deposit-in-oil slurry ahead of the pig was specially designed to measure the volume of deposit during pigging in actual field. The model predictions agreed with the field measured results excellently with a relative error being −10.9%. Of more importance, some pigging issues are discussed in combination with the data from the laboratory simulations and field pigging operation.