Conference paper
Reaction of Sulfuric Acid in Lube Oil: Implications for Large Two-Stroke Diesel Engines
Department of Chemical and Biochemical Engineering, Technical University of Denmark1
CHEC Research Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark2
The Hempel Foundation Coatings Science and Technology Centre (CoaST), Department of Chemical and Biochemical Engineering, Technical University of Denmark3
MAN Diesel and Turbo4
Slow-steaming operation and an increased pressure in the combustion chamber have contributed to increased sulfuric acid (H2SO4) condensation on the cylinder liners in large two-stroke marine diesel engines, thus causing increased corrosion wear. To cope with this, lube oils are formulated with overbased detergent additives present as CaCO3 reverse micelles to neutralize the condensing H2SO4.
In this present work, a mixed flow reactor (MFR) setup aims to investigate the neutralization reaction by varying Ca/S molar ratio, stirrer speed, H2SO4 inlet concentration, and residence time. Lube oil samples from the outlet of the MFR were analysed by use of Fourier Transform Infrared Spectroscopy (FTIR) and a titration method.
The MFR results indicate that the CaCO3-H2SO4 reaction is very fast in a real engine, if the cylinder liner is well-wetted, the oil-film is well-mixed, and contains excess of CaCO3 compared to the condensed H2SO4. The observed corrosion wear in large two-stroke marine diesel engines could consequently be attributed to local molar excess of H2SO4 compared to CaCO3 reverse micelles on the cylinder liners.
Language: | English |
---|---|
Publisher: | The American Society of Mechanical Engineers (ASME) |
Year: | 2017 |
Proceedings: | Internal Combustion Engine Fall Technical Conference (ICEF 2017) |
ISBN: | 0791858316 and 9780791858318 |
Types: | Conference paper |
DOI: | 10.1115/ICEF2017-3580 |
ORCIDs: | Lejre, Kasper Hartvig , Kiil, Søren and Glarborg, Peter |