Doctor of Philosophy (PhD), Ohio University, 2010, Chemical Engineering (Engineering and Technology)

The presence of water, even in small amounts, is often the cause of internal corrosion problems in crude oil transportation. Understanding the factors influencing steel pipeline corrosion rates is a safety as well as an economic matter. The objective of this dissertation is to quantify the effects that are known to have an influence on corrosion in crude oil-brine flow. The first effect is the corrosiveness of the brine. Crude oil's compounds can partition between the oil phase and the water phase to create brines with inhibitive or corrosive properties. The second effect is related to which phase wets the pipe wall. This depends on steel wettability and also on the flow pattern. Crude oil's polar compounds can change the steel hydrophilic surface nature. They also change the flow properties. The problem has been investigated at the Institute for Corrosion and Multiphase Technology at Ohio University on a small scale with specifically designed experiments as well as on a large scale, in a 60 meter-long flow loop loaded with 1600 gallons of oil and water. Results show that only a small percentage of the crude oil's complex chemistry controls its corrosion inhibitive and wettability properties. The knowledge generated from these experiments can be used as a useful reference for corrosion engineers and pipeline operators to maintain oil-water flow systems under corrosion-free conditions.

Committee: Srdjan Nesic PhD (Committee Chair); Michael Prudich PhD (Committee Member); Jeffrey Rack PhD (Committee Member); Howard Dewald PhD (Committee Member); Douglas Goetz PhD (Committee Member) Subjects: Chemical Engineering; Chemistry