Experimental Investigation of the Flow Characteristics in Crude Oil Containing Sand and Gas Flowing Along Vertical Pipelines

An experimental study on the flow behavior of crude oil containing sand and air in a vertical pipe with 50 mm diameter was carried out. The experiments were conducted under the following input superficial phase velocities: oil from 0.1 to 2.23 m/s and gas from 0 to 0.34 m/s. Oil was blended with sand in three different volume concentrations, namely, 0.7, 2, and 3%. Two different types of sand were used to investigate the effect of sand size distribution. A comparison between rheological measurements and pipe flow data showed that the stress-strain relationship obtained by the rheometer could be used to predict the transport characteristics in the vertical pipe flow. It was demonstrated that a small gas injection and sand addition can decrease the total pressure and friction pressure gradients. In the oil flow, the injection of air generally increased the friction factor compared to the single-phase flow, especially at low Reynolds numbers. However, the friction factor decreased by adding a small amount of fine sand. The accuracy of the correlation developed in this study was compared with other three correlations widely used in gas-liquid vertical pipe flow.