Determination of Water Content in Heavy Fuel Oil Using a Relative Permittivity Meter

Abstract

AbstractThe measurement of relative permittivity of fluids is a convenient way to identify the amount of each element in a two-component mixture. This approach applies especially to cases in which the permittivities of the two components are far apart from each other, such as determining the water content in heavy fuel oil (HFO). The latter is a high-viscosity and high-density fuel, obtained from residual portions in the distillation process of crude oil. The presence of water in HFO is generally unwanted, and can be a major concern due to equipment degrading, decrease in heat transfer capabilities and loss of burning efficiency. This work addresses the determination of water content in HFO samples, benefiting from the great difference between the relative permittivities of both fluids. A relative permittivity meter designed specifically for this purpose was employed. The meter uses capacitance as its working principle, and comprises a capacitive sensor that is in direct contact with the oil, and a capacitance meter circuit that connects to the sensor. This paper describes both components, as well as the calibration procedures involved in their usage. HFO samples with different amounts of water were prepared and probed in order to obtain a relationship between water content and relative permittivity. The collected data provides enough information to determine the amount of water present in other HFO samples, by measuring its relative permittivity and using adequate interpolation methods.