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Mechanisms of formation of deposition of asphaltenes, resins and paraffins (DARP) are considered. Molecular diffusion based on the influence of the temperature gradient is the main mechanism for DARP formation. The analysis of existing methods against DARP is given. Modern methods of DARP prevention that affect the temperature gradient are aimed at maintaining the oil temperature above the crystallization temperature of paraffin. The cold flow method is an alternative control method which involves cooling the oil to a surrounding temperature. The purpose of the work is to assess the effectiveness of the cold flow method against DARP; its advantages and disadvantages are revealed. In order to assess the effectiveness of the proposed method. The sample of oil and produced water was taken at the pumping station. Using gas chromatography, the fractional composition of an oil sample was determined using the SimDis method. Using a calibration table, a component composition of oil up to C52 was calculated using values of boiling point and equations of fluid state were formed in PVTsim software. Rheological studies of the transported oil are carried out. Based on results of laboratory studies in OLGA software package, a hydraulic calculation of the pipeline was performed for various values of the flow temperature using the “Wax deposition” paraffin deposition module on the Matzain model. Thus, having the flow with temperature equal to the ambient temperature, in 10 days 5.6 kg of paraffin is formed on pipeline walls, whereas in the current conditions it is 100 kg. As a result, it is established that the effectiveness of the application of the cold flow method against DARP is 94 %. Proposed method can significantly reduce production costs associated with paraffin oil transportation.

In recent years, pharmaceutical production has been stimulating the gradual miniaturization of continuous-flow chemical reactors. This process eventually resulted in the emergence of a new generation of microreactors. The advantages of these new reactor types are the flexible production that allows us to quickly reconfigure the scheme, small reactant quantities used for the synthesis, the control of the main reaction parameters with high accuracy. Nevertheless, a decrease in the thickness of the channels where the species contact and react forces us to search for new non-mechanical mechanisms for mixing. This problem is relevant for the slow reaction occurring in a slot where diffusion alone cannot provide mixing at reasonable distances from the entrance. It is also true for the fast reaction that takes place in a frontal manner. In this work, we consider the efficiency of mixing the reactants induced by electro-osmotic flow in a Hele-Shaw configuration with non-uniform zeta potential distribution. As a test reaction, we take the neutralization reaction with simple albeit non-linear kinetics. The reaction occurs between two miscible solutions, which are initially separated in space and come into contact in a continuous-flow microreactor. The reaction proceeds frontally, which prevents the efficient mixing of the reactants due to diffusion. Using direct numerical simulations of 2D and 3D flows, we demonstrate that the zeta potential applied to boundaries can effectively control the mixing rate of fluids by lengthening the front of the reaction. This approach makes it possible to increase the yield of the reaction product.

The paper presents the results of integrating distributed generation (DG) facilities in the distribution grids and internal grids of industrial enterprises. It proves such locations require many more additional relay protection and automation devices, including emergency controls; the cost of such systems is on par with that of a DG facility. The paper presents the prerequisites for equipping DG-enabled power districts with routine and emergency controls (REC). It substantiates the use of phasor measurement units as REC sensors in low- and medium-voltage grids. Presented herein are the fundamental principles behind, and functionality of, REC. The paper proves feasible using offline-computed parameters to implement a REC system for further transition to online software-based computing of steady states and transients.