Journal of Petroleum & Environmental Biotechnology

Heavy oil-water flow patterns in a small diameter vertical pipe under high temperature/pressure conditions

3^rd World Congress on Petroleum Engineering and Natural Gas Recovery

July 20-21, 2018 Sydney, Australia

Jixiang Guo and Yuqi Yang

China University of Petroleum, China

Posters & Accepted Abstracts: J Pet Environ Biotechnol

Abstract:

Oil-water 2 phase flow widely exists in the oil industry with most environments of high temperature and high pressure, such as oil exploitation, transportation and refining. In spite of the great progress about oil-water 2 phase flows, it seems clear that there is room for a great deal more research on the effect of temperature and pressure on heavy oil-water 2 phase vertical flow pattern. The goal of this study is to promote a better understanding of flow patterns of heavy oil-water 2 phase pipe flow, particularly, flow patterns under high temperatures and high pressures. We conducted experimental measurements to examine the upward oil-water flow patterns in a small diameter vertical pipe (0.01 m ID) under high temperatures up to 130 oC and high pressures up to 20 MPa. The viscosity of the oil sample was 584.24 mPa�?�s and the density was 1.899 g/cm3 at 30 oC. All the experiments were conducted with an in-house-built high pressure/temperature flow apparatus. This apparatus is equipped with a view window that allows us to visually observe the upward flow patterns of oil-water 2 phase flow in a 0.01 m ID stainless steel pipe. The effects of pressure, temperature, Input Water Fraction (IWF) and mixture flow velocity on the flow patterns were systematically investigated. We plot the observed flow patterns on a flow pattern map in which input water fraction was used as the y-axis and the mixture flow velocity was used as the X-axis. Based on the measurement results, we can observe the following flow patterns: Water-in-oil dispersed flow (D w/o), water-in-oil bubbly flow (B w/o), water-in-oil slug flow (S w/o), water-in-oil creep flow (CE w/o), churn flow (churn) and core annual flow (AF). Phase inversion was not observed in this work. With an increase in temperature at a given input water fraction, S w/o, CE w/o and churn flow with large water drops tended to transform into B w/o and D w/o with smaller water drops, the CE w/o disappears gradually and the boundaries in the flow pattern maps tend to occur at lower input water fraction values. The effect of pressure on the flow patterns was found to be opposite to that of temperature. The possible causes leading to the changes in the flow patterns subjected to pressure/temperature variations were provided in terms of changes in density ratio, interfacial tension and viscosity ratio between oil and water.