Modelling of the sediment contents of heavy oil fractions The of the study is to develop and to validate a universal model able to describe the sediment content in blends made by heavy fuel, called residuo, and light oil, known as cutter stocks. To find the model two different ways are possible, a thermodynamic or an empirical approach. The thermodynamic approach needs the knowledge of some properties which are very difficult to measured, for this reason an empirical approach has been preferred. To be able to follow the empirical approach, several data are necessary: some are collected from previous studies and some are new.