With the using of a thermographic method reaction of oxidation of dibutylsulfide in a noctane  95,6 %  concentrated  solution  of  hydrogen  peroxide  in  the  mixture  reactor  with  the propeller mixer is studied.

It is established that dibutylsulfide oxidation by hydrogen peroxide in an ekvimoly-arny ratio 1:1 at a temperature of 80 °C proceeds before formation of a dibutilsulfoksid, and at a ratio 1:2 and at a temperature of 100 °C – to a dibutilsulfon.

The increase in amount of hydrogen peroxide and temperature is followed by for-mation of sour products – the sulfoniyevykh and sulfonew acids.

By method of a gas-liquid chromatography it is proved that during oxidation of dibutylsulfide by hydrogen peroxide his destruction doesn't happen.

The created heat pump complex allows to utilize simultaneously different types of secondary energy resources of petrochemical industries. The main potential for the resources used for the developed heat pump complex is the heat of flammable waste gases and heat of circulating water, and the final received energy resources are heat of heati ng water with a temperature of 150°0C and electricity for internal and external consumption.

The composition of the gaseous fuel can vary widely, depending on the source, time and stage of development of a particular field. Changes in composition leads to a change in the thermophysical characteristics of the fuel, which affects the stability of the operation of the boiler units. This article presents the results of a numerical simulation of the stabilization of heating capacity and the completeness of combustion of associated petroleum gas (APG) in the event of a prolonged, continuous change  in  its  composition. The simulation was  carried  out  using  the previously developed algorithm for optimizing the combustion process of the hydrocarbon fuel (HCF) of variable composition. The simulation results showed that with a slow continuous change in the fuel low heating value with a relative rate of change of 1% during the time of thermal inertia, the stabilization of the operation of the boiler according to the proposed algorithm allows maintaining the steam temperature at the outlet within 10% of the required.

Prandtl’s two-layer model of the turbulent boundary layer is considered and the expression obtained through the use of the model is applied to calculate the heat transfer coefficient, calculations for which agree well with experimental data on mean values of the coefficients for various bodies. Determination of parameters of this expression is shown for the case of calculating local heat transfer coefficients in the entrance regions of the channels. The main parameters are  dynamic velocity, dimensionless thickness of  the  boundary layer  and dimensionless thickness of  the  viscous  sublayer.  Based  on  the  power-law  and  logarithmic velocity profiles, expressions are obtained for calculating the dimensionless parameters of the turbulent boundary layer. A satisfactory agreement of the results of calculations of loc al heat transfer coefficients for the flow over a flat plate and the pipe flow is shown. The presented approach represents a theoretical basis for modeling the local heat transfer for bodies of more complex shapes, if the friction coefficients are known.

The thermodynamics analysis of processes flowing into the storages of compressed  air energy are considered in the paper. The exergy balance has been propose as the instrument for study. The main indices have been estimate: the compressed air potential, efficiencies for all elements of the scheme and air-accumulating electric station (AAES) as a  whole. The study procedure demonstrated on the example of adiabatic AAES. The relation of final temperatures, specific exergy and compression work per 1000 m3  of atmospheric air to compression ratio are determined. On the base, it can concluded that adiabatic AAES has not high efficiency, but it has some advantages: simple scheme, low investment, and combined well with renewable energy sources, for instance, wind-driven plants. To raise the efficiency of an adiabatic AAES, it should be transform to diabatic type. For that it is required modify the scheme and work regime of its elements, and combined it in complex with gas turbine plants.

In this article analysis of the energy system of the Republic of Yemen, its composition and characteristics of the transmission lines, power stations and substations, it also considers the prospects for the development of the power system in the country.

The conditions and characteristics of ice formation on the pipe surface of a heat pump evaporator which depends on water ( at a temperature lower than 280 K) as a low-grade energy source are investigated experimentally. Under the operating conditions of this heat pump, the ice thicknesses and temperatures values at freon pipe wall and for water in the evaporator are registered. The results allowed us to make a conclusion of the possibility to use a water source heat pump in practical applications under the conditions of partial ice coverage for the evaporator surface to heat up water in a condenser to 313 K. It is established from experiments that with the decrease in water initial temperature in the evaporator by 6 degrees, the maximum value of formed ice thickness on the evaporator surface is increased by 30 %. The dependence of Nusselt number on the natural convection characteristics undergoing phase change is established. 

This article deals with the issues of an objective assessment of the technical condition of asynchronous motors with voltage up to 1000 V. A stand is proposed for post-repair tests. Test stand allows you to conduct induction motor tests to form an objective conclusion about the technical condition and quality of the repair carried out automatically.

The article proposes a method for selecting options for the reconstruction of the power  supply  system  based  on  the  criteria  of  decision-making  theory.  The  reconstruction process  is  considered  as  a  sequential  game  with  two  players :  active  and  passive.  The probability of possible states of the system is determined on the basis of the fuzzy sets theory. The main criterion for the choice of the reconstruction option is the value of damage from the power  supply  interruption.  The  application  of  the  proposed  method  is  considered  on  the example of a large metallurgical enterprise.

In  modern power systems, the special kind of measurement systems was actively implemented for the last 20 years. These measurement systems have a high-precision synchronized time stamp, which makes it possible to obtain, in addition to the effective value of line current and bus voltage, the electrical phase angles. In previous years, a large number of methods for obtaining a steady state based on telemetry (state estimation) have been formed, which are based on taking measurements of only the modules of these quantities, as well as the values of the active and reactive components of injection power in the nodes and flows in the branches. Most of these methods were based on the weighted least squares method, or other methods based on the maximum likelihood method, for which determination of the weighting factors of measurements, traditionally chosen on the basis of relative errors of these measurements, is required. However, there is the problem of taking measurements of electrical angles, for which the relative error is fundamentally indeterminable. There is also a problem associated with the integration of measurements of phasor measurements with traditional measurement tools into a single measuring system due to a significant difference in accuracy and update frequency. The paper proposes an approach for combining phasor measurements with traditional SCADA measurements in the framework of the state estimation procedure, taking into account the problems described.

In work results of calculations of main units of steam -turbine mini-thermal power plants of low power: 6, 11,4, 12, 20 and 25 MW intended for work in the autonomous mode are presented. On the basis of material, thermal and the exergy balances efficiency indicators – the exergy efficiency and specific expenses of fuel are defined. With a greatest exergy efficiency at the  level of  33%  have  MW  blocks 6,  20  and  25  that testifies to  a  possibility of  effective combination of the boiler and turbine equipment of this power and also completing of technological schemes of mini-thermal power plant on the basis of the released drying and mill equipment, boilers and turbines of low power.

This  article  presents  the  three  phase  short  circuit  impact  on  synchronous motors stability research results. The analysis of the researches done in this field shows that they neglect following features in motor operation: the voltage sag form occurred during short circuit; dependency of voltage on the motor busbars from the currents passing in the power supply grid elements; the impact of sag through excitation system. Research conducts the voltage sag form equation for the three phase short circuits occurring in the adjacent electric lines. Synchronous motor model was developed to account the impact of neglected factors on the motor stability. Finally, article proposes the methodology developed to assess synchronous motor stability under three-phase short circuit faults occurring in power grids. Research results could be used to calibrate protective relays used in power supply grids with powerful synchronous motors.

Our article reviews the issues arising during the process of wastewater purification and utilization of spent adsorbents. We are offering different ways of utilization of spent sorbents produced  from  residual  biomass  of  Chlorella  Sorokiniana  microalgae  and  Lemna  Minor duckweed. We review the technology of adsorbent production from agricultural waste (carbonized millet husks), wastes of the thermally expanded graphite and chitosan biopolymer production, and residual biomass of Chlorella Sorokiniana microalgae and Lemna Minor duckweed, which is formed after all the valuable components have been extracted from the algae and duckweed. We have conducted a thermogravimetric analysis that demonstrated that the spent sorbents’ decomposition when exposed to high temperatures results in a variety of exothermic effects in the 300 to 500 °C range. This fact allows us to recommend application of spent sorbents as a fuel for energy generation.. For the first time we determine the specific heat of combustion of spent sorbents used in wastewater purification from oils (22,857–25,220 kJ/kg) and from heavy metal ions (19,079–21,117 kJ/kg). We demonstrate that the value of specific heat of combustion of spent sorbents produced from residual biomass is not less than that of classic fuels such as coals and brown coals. The specific heat value of combustion of spent sorbents used in wastewater purification from oils is higher than that of those used in wastewater purification from heavy metal ions because of the oil carbohydrates adsorbed on sorbents, which increases the  material’s calorific value.

The problem of the existence of common-mode and exchange power fluctuations when parallel operation of synchronous generators in autonomous electrical systems is considered. The methods of mathematical modeling obtained the amplitude and period of common-mode oscillations in the whole possible range of settings of the object under study. A method has been developed for constructing maps of the dependence of the amplitude and period of common-mode power oscillations on the values of the transfer coefficients and setpoints in terms of the rotation frequency of the speed governors of diesel generators. The use of such cards allows you to apply the  method  of  eliminating  exchange  power  fluctuations,  taking  into  account  the  possible occurrence of common-mode oscillations. Mapping the settings of the amplitude and the period of the  common-mode  power  oscillations  makes  it  possible  to  understand  the  tendency  of  the amplitude and the period of the common-mode power oscillations to change and to carry out an in-depth analysis of the operation of the autonomous electrotechnical complex.

The presented work offers the stochastic description of the  Stephan’s problem in hyperbolic representation equation. This description is based on the generalized Fоккеr-Plank-Kolmogorov equation. The basic thesis of this work is that the determined equalizations and their decisions are the average values of stochastic Stephan’s task model. This work considers the problem of phase transition front deformation. The research is performed using the entered position of stability on dispersion of decisions for average values. The conclusion of the study is that Markov’s diffusion coefficient leads to a significant distortion of the originall y flat front of the phase boundary.