Determination of the Reference Density of Oil and Liquid Petroleum Derivatives

The storage of products at an oil and petroleum derivatives terminal primarily requires quantitative measurement during the processes of receipt, delivery, and storage. Measurement of density is required in many applications within the hydrocarbon industry, including the measurement of mass and volumetric flow, detection and quality control, as well as the determination of concentration. Modern technology provides the capability to measure density using a densitometer as a standalone device, or by means of a Coriolis meter, which simultaneously enables the measurement of both density and liquid flow rate. In this paper we proposed the formula that enables direct calculation of the reference density of the measured fluid. The advantages of the proposed formula are significant, as it eliminates the error introduced by the API tables, which provide only averaged density values valid for wider density ranges. In addition, the proposed formula solves the problem of cases where data for certain liquids are not available in the API tables. Since density is a key parameter in loss control systems, and considering the importance and application of reference density in quality control processes, where high accuracy is crucial, there is significant justification for further research and application of the newly proposed formula. In this paper, the analysis is based on data and measurement results obtained during the diesel fuel transfer process at the “Ilinden” – Makpetrol Skopje terminal in North Macedonia.