Solution of the problem of bilge and oily water separation can dramatically affect the reduction of the natural resource's volumes used and improve the quality of control over the state of the ecology and biosphere on our planet. The main problem of all separation technologies is the impossibility of obtaining a highly concentrated mixture of oil products. The article describes a new approach based on the use of ultrasonic and artificial ventilation to create a zone of stable supercavitation and water extraction from it. The main physical principles and methods for controlling the size and behavior of the cavitation cavern are considered in detail. For the first time, a method for calculating the main characteristics of separation process was described and an algorithm for its use is shown. Limitations of the depressurization process of the channel for the removal of saturated water steam are described and an assessment of the effect of the bilge water composition on the process of its separation is done. An assessment of the efficiency degree for the bilge and oily waters separation process was obtained in experiments and numerical limits for the optimal range of separator's operation were formulated.

The operation of offshore vessels is directly related to the use of flexible pipelines. The article describes in detail the analysis of power, geometric, kinematic and technological parameters that affect the main operational characteristics of these pipes during their operation under water, in rough sea conditions and under wind loads. The article describes the degree of dependence between loads on the pipeline and velocity of the oncoming flow, the geometry of the pipe and the distance to the rigid surface of the ship’s hull or the seabed. It was determined how the flow velocity during parametric oscillations of the pipeline in unrestricted flow and near the surface of the seabed affects the change in its drag and lift coefficients. An estimate of operational limits of flexible pipeline instability was obtained. On the base of changes in distributed load, specific values for safe lengths of pipelines were formulated. It has been stated that the probability of failure-free operation of a flexible pipeline at a level of 0.99 is directly determined by the frequency of its oscillation. Its numerical values should always be at a level that does not exceed 3.7% of the frequency of pipe dynamic oscillations.

Bilge and oily water (BOW) during vessel’s operation are the most large-tonnage type of waste and for their treatment all ships, in accordance with regulatory requirements [14], have to be equipped with special equipment – oily water separators. At sea vessel’s operating conditions three main directions of BOW cleaning are now used: physical, chemical and biological. The analysis of BOW separation methods based on these three directions has shown that it is very difficult to obtain secondary petrochemical products. In the article authors offer a new method for BOW separation which is based on the use of a hydrodynamic process of supercavitation with artificial ventilation of the cavitational cavern. With local origin in the flow of a supercavitating cavern, there will always be saturated water vapor inside of it. The process of permanent water vapor selection from the cavern will ultimately contribute to the production of highly concentrated mixture of secondary petroleum products from initial mixture of BOW. During the study of BOW separation process it was found that decreasing of the working pressure inside the working chamber of the cavitation separator have to be always compensated by an increase in the temperature of the processed multiphase flow.