This article contains results of exergic analysis of kraft pulping flow chart. The results of exergic balances of main kraft pulping processes such as alkali recovery at recovery boilers, black liquor evaporation, chips cooking, lime decarbonation are considered in details in the article. The analysis of the process flow chart makes it possible to determine the bottlenecks in the use of heat energy and to substantiate principal lines for increasing energy efficiency of the processes under study. A main share of the exergy expended in the existing pulping process is due to alkali recovery in the recovery boiler and comprises 70% of the total exergy available in the system. A procedure of hydrothermal production of chemicals in the process of kraft pulping is studied. A schematic diagram and analysis of heat technique of the kraft pulping process which in fact consists of organic component removal from black liquor through its autoclave carbonation with flue gases releasing from lime kiln at the temperature 80-90 oC are given in the article. The removal of organic components under these conditions can reach 70 %. In the studied version the exergic efficiency ηe = 80 % is considerably higher than that of the flow chart existing for chemicals recovery which is equal to ηe = 48 %. This is the evidence of high energy efficiency of the method developed.

The problem of determination of temperature fields in the flow and efficiency of heat exchangers with intensification by metal chaotic packings is considered. Results of experimental studies of the heating of industrial oil with hot water in a "pipe-in-pipe" heat exchanger, where a chaotic packing of nominal size 6 mm is placed in the internal pipe, are presented. The packing, due to turbulence in the flow of oil, provides transition from the laminar to the turbulent regime and a significant increase in heat transfer coefficient (by 15-20 times). For calculating temperature profiles in channels, a cell model of the flow structure is written, where the main parameters are thermal number of transfer units and number of complete mixing cells. Expressions are given for calculating these parameters in pipes with chaotic packings. Results of calculating temperature profiles for various flowrates of the heated oil are presented and satisfactory agreement with experimental data is shown. The calculation of temperature fields makes it possible to take into account a change in thermophysical properties of flows along the length of the channels, which is especially important for hydrocarbon mixtures with high viscosity and large Prandtl numbers. The presented mathematical model allows to take into account the structure of heat carrier flows in apparatus with intensifiers and to calculate thermal efficiency of the processes of heating and cooling the media.

Much attention is paid to the consideration of the causes of transformer oil aging under the influence of technogenic and natural factors. The paper insulation destruction mechanism is considered, as a result of which furan compounds are formed that enter the transformer oil and worsen its dielectric characteristics. The characteristics of the domestic transformer oil grade GK-1 obtained using the technology of hydrocracking in a hydrogen medium are given. Furan compounds are formed in used transformer oil, which are monitored using chromatographic analysis methods according to standard procedures. The group composition of transformer oil was determined using thin layer chromatography. As a solvent used n. Hexane. To extract furan compounds from transformer oil, various organic solvents are used, the physicochemical properties of which are given in this work. It was found that the retention time of the studied sorbates corresponds to an increase in their boiling points for ethyl acetate, methyl ethyl ketone and dodecane. In the case of isopropanol, which has a close boiling point with ethyl acetate and methyl ethyl ketone, a significant increase in retention time is observed, which is associated with the formation of an intermolecular hydrogen bond. The dependence of the spot diameter of furan substances on their concentration was established under conditions of thin-layer chromatography on Sorbfil plastics. Moreover, the most effective separation is characteristic of furfural. In this case, the chromatographic spots are small in size with good fidelity. The ascending mode of column liquid chromatography was used to determine the dependence of the retention time of standard sorbates on the length of the Silyochrome S-80 sorption layer, which is parabolic. It was found that the highest retention times are characteristic of ethoxyethanol and isopropanol, which is consistent with the known theoretical principles of liquid chromatography. Histograms of the effect of the retention time of standard sorbates on their nature and boiling point, where isopropanol and 2-ethoxyethanol are extreme, are presented. In this case, isopropanol having a lower boiling point than 2-Ethoxyethanol is retained on the sorbent more strongly, which is associated with the formation of intermolecular hydrogen bonds with surface silanol groups of the sorbent.

The ACS150 frequency Converter was chosen as the object for experimental research. On the basis of the measurements it is concluded that in the spectral composition of current drawn by the frequency Converter, in addition to currents the main harmonic component is dominated by currents 5, 7, 11, 13, and 17th harmonics, i.e. harmonic components of odd non-multiple of three. Currents 3, 9 and 15 th harmonic components are also present in the spectral composition, but their value is much smaller. Also, based on the data obtained, it can be argued that with a decrease in the frequency of motor speed control and the load value of the frequency Converter, the number of pulsations on the current waveform increases, as a result, there is an increase in the values of the higher harmonic components and an increase in the value of the total harmonic components of the current. The main contribution to the increase in the index of the total harmonic components of the amperage with a decrease in the load of the frequency Converter and the output frequency of the motor speed control is made by odd harmonic components of the amperage multiple of three, at the same time harmonic components of the amperage non-multiple of three, namely the 5th and 7th order, are not subject to change. A brief review of technical solutions aimed at improving the electromagnetic compatibility of asynchronous frequency-controlled drive is given. In particular, such solutions as increasing the number of semiconductor switches used in inverters, improving control modes, the use of special separation transformers, passive (resonant) and active filters are noted.

Reliability of power supply of consumers is an important task in the process of transmission and distribution of electric energy. The paper proposes a method for assessing the consequences of power failures of monoconsumers of electric energy on the example of an oil company and an adjacent power grid company. The uniqueness of the developed technique lies in the possibility of reliable calculation of reliability of power supply of complex branched electric networks without taking into account the specific scheme of power supply. The accuracy of calculations is increased due to the use of data directly studied power system, taking into account the specifics and operating conditions of specific equipment, instead of the average information. Classification of failures on the main reasons in electric networks of the oilproducing enterprise of the far North that allowed to develop actions for increase of level of reliability of power supply is made.

One of the key aspects in the development of power engineering all over the world is the use of distributed small-scale generation. This is both based on fuel carbon resources with a synchronized connection between sources when they are connected to the electric power grids and renewable energy sources operated in the electrical grid via frequency converters (electronic generation). The latter brings an inevitable broad use of inverters in available AC power systems. The objectives of this paper are numerous. First is the desire to study the effect of electronic generation on modes and stability of current electrical grids and electrical power systems. Another objective is to establish requirements for electronic generation control that lets us minimize actions on relay protection coordination and automation upon the integration of electronic generation in power grids. A final objective is to increase the reliability of general electrical modes. This article shows the outcomes of the study on the statical aperiodic stability of the electrical power system upon the integration of electronic generation, requirements for its statical characteristics, and the control when operated within the electrical power system.

The article examines the main features of the layout of electrical equipment for shop networks of internal power supply with the definition of indicators for a group of shop customers connected to a single power center, affecting the choice of the structure of schemes for shop network sites. The parameters characterizing the circuit topology are revealed. A study is presented of the influence of the load factor of workshop transformers on their reactive power factor, it is proved by calculation by technical and economic criteria the feasibility of replacing a workshop transformer with two with a lower total power. The calculation of energy savings in the in-plant power supply systems. The type of dependences tgφ of transformers ТМ and ТСЗ with various rated powers in the function of loading transformers is established. The most significant factors of the growth of idle power losses during operation are presented. With determination of losses of active and reactive power and electricity in transformers and losses of active power in a high voltage distribution network A feasibility study was carried out on the options for internal power supply schemes with two transformers of lower power installed instead of one, and the feasibility of such a replacement to increase the efficiency of the equipment was proved and the estimated payback period for the investment capital was determined. A comparative analysis of the studied power supply schemes of industrial enterprises with the identification of their advantages and disadvantages.

Ventilation and air conditioning systems are necessary to regulate air exchange, maintain temperature and humidity, and provide a comfortable microclimate. Their installation is certainly relevant in premises for various purposes: at industrial facilities, in residential buildings, in administrative institutions, warehouses and others. In order to effectively carry out and ensure the proper functioning of ventilation, it is necessary to introduce automated control schemes for the operation of these systems, as well as the use of various modern equipment (ventilation units, ventilation units, silencers, air filters, air heaters, etc.) to increase the reliability of airspace cleaning and the cost-effectiveness of manufacturing the system generally. The paper presents the scheme and algorithm for the effective control of the technological process of the ventilation system of an industrial enterprise based on the TM171PDM27S Schneider Electric programmable logic controller. The analysis of existing ventilation systems is carried out, the description of ventilation systems is presented, the stand's appearance is presented, the choice of a programmable logic controller is justified, methodological recommendations for acquiring programming skills using the EcoStruxure Machine Expert - HVAC environment are presented, automatic control of the supply ventilation system for the foundry of an industrial enterprise is organized goals of a visual study of elements of ventilation systems, methods of regulation and control of parameters in ventilation systems. The main goal of creating a training stand is to study the settings and operating modes of automated ventilation and air conditioning control systems. In the course of further improvement of the circuit, classes of the following nature are possible: determination of the static and dynamic characteristics of the fan; study of the characteristics of an automated damper; pressure regulation by controlling a fan, etc.

In the process of functioning working sets with electromechanical converters included in their composition, it is necessary to take into account the influence of endogenous and exogenous disturbances that cause deviations of the parameters of electric machines from the nominal values given by the manufacturer in the appropriate documentation. These deviations of the parameters, even those within the permissible range of changes, have a noticeable effect on the quality of functioning of electromechanical converters and working sets as a whole. During the life cycle of the work of electromechanical converters, their parameters change as a result of natural wear and senescence, which necessitates continuous or periodic analysis and monitoring of the state objects under study. The paper considers a method based on the calculation of the linear integral criterion Q and the formation of Q – tables, which allows monitoring the functioning of electromechanical converters with unstable parameters during operation as part of working sets. Simulink – models of linear integral criterion calculation system and system of automated monitoring of electromechanical DC converter parameters are presented, which allow estimating unstable parameters. In these models static characteristics are implemented in tabular form reflecting the dependencies between the parameters of the electromechanical converters and the linear integral criterion. The results of the study allow us to obtain estimates of changes in the unstable parameters of electromechanical DC converters with the required accuracy.

At high ambient temperatures, the performance of gas turbine power plants drops significantly. Technical solutions of compensation for losses associated with the constant injection of water into the air intake of a gas turbine. This approach is not acceptable in regions with limited fresh water reserves. Radical solutions are required to reduce the cost of generated energy. Integrated Combined Solar Cycle (ISCCS) technology has proven itself on many projects. The addition of a combined cycle gas cycle with solar energy can significantly increase the overall efficiency of the power plant. Despite the increase in costs during the construction of its solar part, the total cost of operating solar collectors is several times less than a turbine installation. Given the global trend to fight carbon emissions, switching to a hybrid scheme is economically attractive. Trading in carbon credits for CO2 emissions will significantly reduce the payback period for the construction of gas turbine modernization under the ISCCS scheme. This paper presents an option to modernize a gas turbine power plant in the city of Basra (Iraq), using the advantages of solar radiation and recycling of combustion products from gas turbines. It is proposed to equip the existing 200 MW gas turbine plant with two steam turbine units with a capacity of 75 and 65 MW, working in conjunction with solar collectors producing low pressure water vapor. Due to modernization, the efficiency of the power plant should increase from 38% to 55%. The revision of the schematic and technical solutions of Iraq power plants will allow producing sufficient energy for the region.

The article describes a bench for studying a system of a flow analyzer based on nuclear (proton) magnetic resonance (PMRA), used for the operational control of proton-containing multicomponent liquids (oils, fuels, oil and chemical products) and mixtures for viscosity and composition (concentration of asphaltenes and resins ) during oil production, oil preparation and use at energy facilities in the analysis of liquid fuel. This article also looks at the equipment that is used to control oil parameters with PMR-Relaxometry. Particular attention should be paid to the analysis of physical and chemical properties of oil components with the use of PMR. The use of sampling equipment for the purpose of controlling the rapid flow of oil parameters by the PMR method will eliminate phase separation in the sampling device and eliminate clogging with waste sediments, ensure efficient homogenization of the fluid flow in the sampler, as well as automate the measurement process.

On the basis of the two-channel remote measurement method previously developed at the Department of PES KGEU, a set of characteristics of the PD with the simultaneous use of electromagnetic and acoustic sensors, which allows you to remotely measure and evaluate the technical condition of high-voltage insulators (HVI). The article presents the results of developments in the development of the previously proposed method, which allowed to determine not only the type and location of the defect, but also its size and the degree of influence on the working condition of the VI. Particular attention is paid to the evolution of defects under the influence of overvoltage and other electrophysical processes in operating conditions. In particular, the generation of ultra-large PDs that can create erosion of the dielectric surfaces of defects was recently discovered, and the technical condition of highvoltage polymer insulators was examined. All measurements were performed on an experimental bench by non-contact receiving pulse signals of the PD by an electromagnetic tunable receiver in the range of 50-600 MHz. Their indication and computer processing were carried out in order to determine in each of the discrete intervals of the phase voltage the average values of the number and intensity of PD pulses, which either do not exceed the allowable threshold for the occurrence of defects and their development, in comparison with the reference HVI, or exceed it. Based on the results of preliminary bench tests on model specimens and real HVIs under operating conditions, and the obtained set of PD parameters, diagnostic signs were established that made it possible to determine the type, location of the most dangerous defects and the degree of their influence on the HVI working capacity. At the same time, the presence of the most dangerous defects is determined by the expansion of the phase intervals of PD radiation, a sharp increase in PD in negative half-periods of high voltage compared with positive half-periods, and also by a significant difference in the width and shape of single PD pulses.