An accurate prediction of wax deposition profiles along a production line has significant impact on savings, pipeline design, flow assurance and operations of waxy crude production system in oil industry. Validation of wax deposition model by a field test is a necessary step to ensure accuracy of the modeling results.

A field, located in Northeast China, was chosen for the field test. A pipeline was installed between wellhead and original production line. After 18 days of field test, the pipeline was disassembled and cut into 31 pieces. The amount of wax deposition in each piece of pipe was measured and recorded. In the field test pipeline, waxy crude was transported under multiphase flow conditions at temperatures below pour point. The wax deposition model is a semi-empirical model to include molecular diffusion and shear effects. A scaler is proposed for the modeling. The accuracy of this model relies on the accurate experimental data obtained from the special wax-deposition-flow-loop test procedures. The state of art wax deposition flow loop, built in Beijing, China by two oil companies, can accurately and cost effectively determine wax deposition tendency and rheology of waxy crude from temperatures above the oil cloud point to ambient.

A recombined live oil was used in the laboratory flow loop tests. The laboratory data and the field operating conditions were input to the wax deposition model. The modeling results were compared to the field data for validation. The accuracy of the modeling results and modeling technique are discussed in this paper.

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