Crude oil, having a paraffin nature, has been studied extensively in the small-scale flow loop at Tulsa University ParaffinrnDeposition Projects (TUPDP). The effects of turbulence/shear and thermal driving force on wax deposition characteristicsrnwere experimentally studied using a waxy crude oil from the Gulf of Mexico. The test matrix consisted of a total of 15rnexperiments which include 12 short term tests and 3 long term tests. The tests were conducted under different operatingrnconditions with a wide range of Reynolds numbers from 3,700 to 20,500. The shear stress ranged from 5.4 to 53.9 Pa.rnIt was observed that paraffin deposition is highly dependent on the thermal effective driving force which is therntemperature difference between oil bulk and initial inner pipe wall and also on turbulence effects. The deposit thicknessrnobtained using both the pressure drop method and a direct measurement was found to decrease with increasing shear stress andrndecreasing thermal driving force. The wax content showed a gradual increase with an increase in flow rate. For the short termrntests, the deposit mass with no entrained oil seemed to increase and then decrease with an increase in initial shear stress andrndecrease in effective thermal driving force whereas the total deposit mass was found to decrease with an increase in initialrnshear stress or decrease in effective thermal driving force.
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