The article shows studies of the problem of active sediment formation during mixing of residual fuels, caused by the manifestation of incompatibility. To preserve the quality and reduce sediment formation during transshipment, storage, and transportation of marine residual fuels, a laboratory method for determining the compatibility and stability of fuels has been developed, which makes it possible to determine the quantitative characteristics of the sediment formation activity. According to the method developed, laboratory studies have been carried out to determine incompatible fuel components and the influence of composition on the sedimentation process. Tests were carried out to determine the quality indicators and the individual group composition of the fuel samples. Based on the results of the studies, the dependences of the influence of normal structure paraffins in the range from 55 to 70 wt. % and asphaltenes in the range from 0.5 to 3.5 wt. % in the fuel composition on the sedimentation activity due to incompatibility were obtained. To obtain a convenient tool that is applicable in practice, a nomogram has been developed on the basis of the dependences obtained experimentally. It was also determined that, after reaching the maximum values of sediment formation with a further increase in the content of n-paraffins, saturation is observed, and the value of the sediment content remains at the same level. Maximum total sediment values have been found to depend on asphaltene content and do not significantly exceed them within 10%. The results of the research presented in this article allow laboratory and calculation to determine the possibility of incompatibility and to preserve the quality of marine residual fuels.

Providing quality fuel to ships with reduced SOx content is a priority task. Marine residual fuels are one of the main sources of atmospheric pollution during the operation of ships and sea tankers. Hence, the International Maritime Organization (IMO) has established strict regulations for the sulfur content of marine fuels. One of the possible technological solutions allowing for adherence to the sulfur content limits is use of mixed fuels. However, it carries with it risks of ingredient incompatibilities. This article explores a new approach to the study of active sedimentation of residual and mixed fuels. An assessment of the sedimentation process during mixing, storage, and transportation of marine fuels is made based on estimation three-dimensional diagrams developed by the authors. In an effort to find the optimal solution, studies have been carried out to determine the influence of marine residual fuel compositions on sediment formation via machine learning algorithms. Thus, a model which can be used to predict incompatibilities in fuel compositions as well as sedimentation processes is proposed. The model can be used to determine the sediment content of mixed marine residual fuels with the desired sulfur concentration.

Tanks for storing oil and oil products during operation are exposed to a combination of external, static, low-cycle, temperature, snow and wind loads, bottom sediments, etc., which leads to a decrease in operational reliability and a decrease in the durability of tank structures. Numerical modeling methods, in contrast to standard methods for calculating strength and stability, allow us to create an adequate finite element model at the stage of development of a geometric model. This article describes the analysis of the stress-strain state of the tank taking into account bottom sediments of oil products and the influence of the temperature of the oil product and the environment using the Ansys software package. Based on the analysis of the stress-strain state using finite element modeling on the example of a vertical steel tank, it was shown that the stresses in the zone of the miter weld, as well as in the places of installation of the receiving-distributing branch pipe and the manhole, are maximum. It is in these zones that the influence of bottom sediment and temperature is significant, since they form local elevated stress zones, which increase significantly when the walls are thinned.

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Storage tanks for petroleum products must comply with the requirements of technical, technological and environmental safety. The corrosion rate increases with prolonged storage of petroleum products in tanks. To prevent the destruction processes for reliable operation of tanks caused by metal corrosion some solutions are needed. Active formation of general sludge occurs in the storage of fuel oil, which contains corrosion-active substances, because of the incompatibility of fuels. The paper assesses the effect of total oil sludge in tanks on the corrosion process and on the reliability of tanks. Studies of the formation of a common sediment caused by incompatibility when mixing petroleum products are conducted. The paper proposes a solution which allows to reduce the formation of total oil sludge and to ensure reliable operation of reservoirs.