Pipeline Pressure Drop in Heavy Oil Production

Abstract

Increased energy demand and declining conventional oil production initiated the interest in unconventional resources, such as heavy oil and bitumen. Their potential is huge, as they make up 70 % of the world s discovered petroleum resources. Only a small fraction of the heavy oil resources has already been developed and produced, due to the challenges involved in heavy oil production.The high viscosity of heavy oils causes the pressure drop in pipelines to be much higher than for conventional oil. This translates into production and transportation challenges and higher required pumping power. Co-production of water and heavy oil might lead to formation of stable emulsions of even higher viscosities than the heavy oil alone. However, emulsions with significantly lower viscosities may also form under the right conditions, making emulsions a possible production strategy.This thesis examines the technological challenges in extracting, producing and transporting heavy oil. The emphasis is on pressure drop in pipelines, where the goal is to detect the effect viscosity has on the pressure loss during pipe flow. Investigation of the pressure loss is done by calculations in Excel, using correlations and heavy oil properties found in the literature. The obtained results show that viscosity has a larger impact on the pressure loss than the heavy oil density. Reducing the viscosity by 75 % translates into a 69,5 % reduction of the total pressure loss.Emulsion viscosity prediction requires experimental for accuracy. However, the correlations used in this thesis suggest that it is possible to transport as much as 60 vol% heavy oil as oil-in-water emulsions. With a resulting emulsion viscosity that is only a few times larger than the water viscosity.