Solvent‐free quantification and composition/source analysis of total oil and grease in cooling water

Abstract

AbstractTotal oil and grease (TOG) in water is measured in industrial process waters to determine the concentration of petroleum products present. A common application for TOG measurement is to detect a hydrocarbon leak in circulated cooling water systems. A hydrocarbon leak from a heat exchanger has a negative effect on the stable operation of upgrading and refinery units. Detecting and quantifying a hydrocarbon leak is straightforward; however, identifying the source of the leak can be very time consuming and require a lot of trial and error. In this study, a solvent‐free TOG method using ClearShot extractors and Fourier transform infrared spectroscopy (FTIR) was developed and optimized for the quantification of bitumen derived hydrocarbon analytes in water. This was further expanded upon to develop a rapid method for hydrocarbon identification in the cooling water by combining chemical fingerprinting with a discriminant analysis classification model. Following the optimized solvent‐free TOG method, chemical fingerprints for six different hydrocarbon classes in water were analyzed by FTIR. The classification model for these hydrocarbon classes was constructed using a discriminant analysis algorithm with a 100% classification rate at a TOG mass loading greater than 150 μg. The optimized solvent‐free TOG method decreases exposure risk and ergonomic strain for technologists, improving overall safety and environmental performance. The hydrocarbon fingerprinting enables rapid prediction of a leak source which reduces the time and analysis required to isolate a leak as well as reducing the cost and environmental impact associated with blowdown and purge (disposal and treatment) of contaminated water.