Перегляд за Автор "Tovazhnyanskyy, Leonid Leonidovich"
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Документ About the Possibilities of the Heat Exchangers Network Retrofit for Post-Combustion CO₂ Capture Unit Without Stream Split(The Italian Association of Chemical Engineering, 2014) Perevertaylenko, O. Yu.; Gariev, A. O.; Damartzis, Theodoros; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Arsenyeva, O. P.There is an increasing interest in post-combustion CO2 capture connected with climate change and further use of captured CO2 in enhanced oil and gas recovery and as a feed to produce such products as methanol, dimethylether and others, use in hot dry rock technologies etc. The currently used post-combustion method with monoethanolamine (MEA) absorption without stream split has two shortcomings: significant steam consumption to regenerate amine solution and relatively high cost of heat exchange equipment of absorption unit or Heat Exchange Network of Absorption Unit (HEN AU). The variation of temperature differences on rich/lean heat exchanger was considered and its influence on heat supply, cost of HEN AU and cold utility consumption was searched. The high effective plate heat exchangers are proposed as components of HEN AU to decrease its cost. The possibility of flue gas stream heat integration for heat supply to the desorber was searched too.Документ Accounting for Thermal Resistance of Cooling Water Fouling in Plate Heat Exchangers(The Italian Association of Chemical Engineering, 2012) Arsenyeva, O. P.; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Demirskyy, O. V.The Plate Heat Exchanger (PHE) is one of the most efficient types of modern heat exchangers. Heat transfer enhancement is one of the main features of PHEs, and lower fouling tendencies render them even more advantages for the use in different applications. The effects on fouling accumulation rate of process parameters in PHE channels of intricate geometry are studied in this article. The asymptotic behavior of the water fouling on heat transfer surfaces is examined. The fouling accumulation rate is described as a difference between the fouling deposition term and the fouling removal term. On comparison with data for fouling on different heat transfer surfaces available in literature it is shown that asymptotic fouling thermal resistance inversely proportional to wall shear stress. The proportionality coefficient in this relation is determined for a number of considered cases. To calculate the wall shear stress the equation for PHE channel main corrugated field is used, which accounts for corrugations geometrical parameters. It is shown that for given fouling properties of water this coefficient is constant and can be determined by monitoring fouling behavior of any item of heat exchangers working on specific enterprise. After that all other heat exchangers of that enterprise can be calculated using that data and developed Equation for accounting of fouling in their design.Документ Ammonia Refrigeration Cycle Integration in Buildings Heating System(The Italian Association of Chemical Engineering, 2012) Boldyryev, S. A.; Kapustenko, P. O.; Tovazhnyanskyy, Leonid Leonidovich ; Garev, A. O.; Perevertaylenko, O. Yu.; Khavin, G. L.; Arsenyeva, O. P.; Klemeš, Jiří JaromírThis work investigates the possibility of ammonia low potential heat utilisation with use of Process Integration methodology. The two operation modes are considered. The first one is the use of ammonia gas super-heating and partly ammonia condensation. The low condensation temperature of ammonia is limiting the low potential heat usage. The second option is introduction of ammonia additional compression to increase the temperature of ammonia condensation. The low potential heat consumers are the hot water supply system, air pre-heating system and air heating for the fans.Документ Catalyst Coatings Carriers Based on Aluminium-Silicon Glass Crystalline Compositions(The Italian Association of Chemical Engineering, 2017) Krasnokutskiy, E. V.; Ved, V. E.; Tovazhnyanskyy, Leonid Leonidovich ; Ved, H. V.A method of deposition on the surface of metals or ceramics catalytically active compounds by attaching them to the intermediate glass crystalline coatings. The effect of the presence of 3d-transition elements in the intermediate coating to modify the activity of a palladium containing catalyst was studied. The basic indicators of the efficiency of non-isothermal heterogeneous catalytic conversion process of benzene depending on the types of transition metals which are part of the intermediate coating were studied. Comprehensive analysis of the morphology of a glass-intermediate secondary catalyst carriers and surface coating them with layers of catalytically active compounds was carried out, which allowed to estimate the effect of the characteristic features of the structure of the coating surface on the rate constant of the process of conversion and mass transfer coefficient.Документ The correlation of experimental results for condensation of steam from its mixture with air in channel of plate heat exchanger based on mathematical modelling(Національний університет "Львівська політехніка", 2019) Kapustenko, P. O.; Tovazhnyanskyy, Leonid Leonidovich ; Arsenyeva, O. P.; Vasilenko, O. A.; Kusakov, S. K.The process of steam condensation in the presence of air in channels of plate heat exchanger is investigated experimentall and with mathematical modelling. The equation accounting for transvers mass flux on heat and mass transfer is obtained. The results allow design of platecondenserss for steam containing noncodensable gas.Документ The Development of Heat Substation for Drying Waste Heat Utilisation(The Italian Association of Chemical Engineering, 2014) Gariev, A. O.; Klemeš, Jiří J.; Kusakov, S. K.; Tovazhnyanskyy, Leonid Leonidovich ; Anokhin, P.; Kapustenko, P. O.; Arsenyeva, O. P.; Čuček, LidijaThe problem solution of waste heat utilization at the tobacco factory is considered in this work. The analysis of the possibility of waste heat utilization and appropriate calculations of plate heat exchangers were carried out. The method for multi component mixture condensation calculation is used. This allows obtaining optimal parameters for the working conditions of the heat exchangers according to the energy efficiency retrofit of industrial enterprises. The design of heat substation for waste heat utilisation was developed.Документ Eco-Friendly Synergetic Processes of Municipal Solid Waste Polymer Utilization(The Italian Association of Chemical Engineering, 2018) Bukhkalo, S. I.; Klemeš, Jiří Jaromír; Tovazhnyanskyy, Leonid Leonidovich ; Arsenyeva, O. P.; Kapustenko, P. O.; Perevertaylenko, O. Yu.The synergetic approach for eco-friendly efficient utilization of Polymer Solid Waste is presented. It is accounting for chemical processes in polymers during the use of the original product and at the stage of its waste recycling. The study of the polymer photoconductive degradation based on analysis of chemical reactions in the polymer film is presented. It is discussed how to predict the properties of the polymer after its use and to develop the efficient technique for its recycling. The recycling technique is demonstrated on examples of recycling polyethylene film by chemical foaming and injection moulding methods. The results of factorial experiments on the influence of different process parameters on process intensity and secondary product quality are presented. The results are used for developing modern technologies for the processing of polymer solid wastes into useful secondary products.Документ Generalised semi-empirical correlation for heat transfer in channels of plate heat exchanger(Elsevier Inc., 2014) Arsenyeva, O. P.; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Demirskiy, O. V.The analogy of heat and momentum transfer in turbulent flow modified for channels of Plate Heat Exchanger (PHE) is proposed. The effects of channel geometry, flow velocity and fluid properties on heat transfer are accounted in the resulting equation, which permits the calculation of film heat transfer coefficients using the generalized correlation for friction factor at the main corrugated field of the interplate channel. The results of calculations are compared with data from experimental study. The good accuracy of film heat transfer coefficients prediction is shown. In the case when the corrugations direction is parallel to the flow direction, the calculations results are quite close to the predicted by the Equation published in the literature for straight pipes. The Prandtl number influence on heat transfer is discussed and semi-empirical Equation for its evaluation is proposed. The comparison with experimental data available in the literature confirmed the accuracy of the heat transfer prediction. The proposed Equation is recommended to be used for optimization of PHEs channels geometry for different conditions in the process industries. It can be employed also for optimizing PHEs heat exchange networks and also to determine PHEs heat transfer area targets when process integration methodology is employed.Документ The Generalized Correlation for Friction Factor in Criss-cross Flow Channels of Plate Heat Exchangers(The Italian Association of Chemical Engineering, 2011) Arsenyeva, O. P.; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Khavin, G. L.The paper concerns with analysis of the influence of corrugation form of PF1E plates on hydraulic resistance in the formed channels. The data for models of the main corrugated field of the inter-plate channel considered. It enables to exclude the influence of entrance and exit distribution zones. The specific type of generalizing formula is used, which correlates the data in a wider range of Reynolds numbers, compare to conventional ones. The equation for hydraulic performance of inter-plate channels with sinusoidal and triangular corrugations shapes is obtained, which generalizes experimental data of different authors available in literature. It accounts for the influence of the corrugation inclination angle to the plate vertical axis and corrugations pitch to height ratio.Документ Heat Integration Improvement for Benzene Hydrocarbons Extraction from Coke-Oven Gas(The Italian Association of Chemical Engineering, 2011) Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Ulyev, L.; Boldyryev, S. A.In present work the extraction of benzene hydrocarbons from coke-oven gas on the one column unit is studied. Energy consumption of the investigated plant is defined and disadvantages of existing heat exchangers network are shown. The integrated flexible flowsheet is proposed based on process integration method. It enables to reduce both hot and cold utilities consumption on 2,872 kW with pay back period about 9 months.Документ Heat transfer and pressure drop in cross-flow welded plate heat exchanger for ammonia synthesis column(2016) Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Perevertaylenko, O. Yu.; Khavin, G. L.; Arsenyeva, O. P.; Arsenyev, P. Yu.Документ Heat Transfer and Pressure Drop in Cross-Flow Welded Plate Heat Exchanger for Ammonia Synthesis Column(The Italian Association of Chemical Engineering, 2016) Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Perevertaylenko, O. Y.; Khavin, G. L.; Arsenyeva, O. P.; Arsenyev, P. Y.; Khusanov, A. E.Plate Heat Exchanger (PHE) is one of the modern types of compact heat transfer equipment, which can significantly enhance the heat recuperation and improve efficiency of energy usage in many industrial applications. The construction of welded PHE (WPHE) can significantly widen the range of its application on temperature and pressure. The results of experimental study of heat transfer and pressure drop in a model of WPHE specially designed for work in ammonia synthesis columns are presented. The model consists of the round plates with special form of corrugations. The plates are welded together forming a pack with channels for two heat exchanging streams. The streams are in a cross flow that correspond to one pass of the multipass WPHE with overall counter-current flow. It is shown that for calculation of heat transfer effectiveness can be used the cross flow model where fluid in one channel is mixed, but in another unmixed. The Equations for calculation of film heat transfer coefficients and pressure drop are presented, which can be used in earlier developed method of WPHE design. The validity of the Equations and developed method of WPHE design is confirmed by the data of tests with WPHE installed in ammonia synthesis column at temperature up to 520 °C and pressure 32 MPa.Документ The influence of plate corrugations geometry on plate heat exchanger performance in specified process conditions(Elsevier Inc., 2013) Arsenyeva, O. P.; Kapustenko, P. O.; Tovazhnyanskyy, Leonid Leonidovich ; Khavin, G. L.The mathematical model of plate heat exchanger (PHE) is developed using decomposition of the plate on its main corrugated field, which cause major effect on heat transfer, and distribution zone, which influences mostly the hydraulic performance. Model is validated on experimental data for some commercial plates. It is shown, that for specified pressure drop, temperature program and heat load the geometrical parameters of plate and its corrugations, which are enable to make PHE with minimal heat transfer area, can be found. The developed mathematical model can be used for designing of plates with geometry, which is in the best way satisfying process conditions of the certain specific range. The case study for conditions of PHE application in District Heating systems is presented.Документ The investigation of vapor condensation in horizontally oriented channels with cross corrugated walls(The Italian Association of Chemical Engineering, 2007) Perevertaylenko, O. Yu.; Nagorniy, E. R.; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.The problem of heat transfer for flows in channels of plate heat exchangers with cross corrugated walls is very complicated, especially relating to two phase flows. The subject of the investigation is the process of vapor condensation in horizontally oriented channels formed by corrugated plates. The corrugation of plates is complicated and consists of different patterns. The experimental investigations were carried out for single phase flow in channels under investigation and for condensation of pure vapor and vapor containing non condensable gases. Appropriate relationships were obtained. The results of investigation were used for development of special plate heat exchanger for condensation column of ammonia synthesis unit, where the condensation of synthetic ammonia occurs. The manufactured plate unit was installed into existing condensation column. The results of industrial tests are in good agreement with experimentally based relationships used for calculations and design of the plate heat exchanger.Документ The Longitudinal Flow of Oil and Petroleum Products in the Channels and Pipes. Part II(The Italian Association of Chemical Engineering, 2017) Tolchinsky, Yu. A.; Tovazhnyanskyy, Leonid Leonidovich ; Ved, V. E.; Kapustenko, P. O.; Krasnokutskiy, E. V.; Ved, H. V.; Satayev, M. I.; Saipov, A. A.A model associated fluid flow and heat transfer of longitudinal flows of oil in pipes and channels is considered. The model is an extended version of the Bingham flow on the case of flow with one or two solid cores. The fluid part is a two-phase medium, wherein the disperse phase may consist of solid particles, droplets and gas bubbles. The sliding on the borders of pipes and channels, thermal conductivity and viscosity of such systems and their impact on the characteristics of the solid core are discussed. The flow with a yield point dependence on the temperature is also considered.Документ Mathematical Model of Heavy Duty Welded Plate Heat Exchanger and its Validation in Industry(The Italian Association of Chemical Engineering, 2017) Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Perevertaylenko, O. Yu.; Arsenyeva, O. P.; Arsenyev, P. Y.; Khusanov, A. E.Plate Heat Exchanger (PHE) is one of the modern types of compact heat transfer equipment, which can significantly enhance the heat recuperation and improve efficiency of energy usage in many industrial applications. The construction of welded PHE (WPHE) is significantly widening the range of its application on temperature and pressure. The construction of investigated WPHE is developed for work in high pressure shell of ammonia synthesis column at pressure up to 32 MPa and temperature up to 520 °C. It consists of the stack of round corrugated plates with diameter 626 mm, which are welded together to form a number of channels for cold and hot streams exchanging heat. The welded collectors of special design are organizing multi pass movement of both streams with overall counter flow. The movement of two streams in one pass block is cross flow with overall counter flow in a whole WPHE. The mathematical model of considered WPHE is developed, which enables to perform the thermal and hydraulic design for specified process conditions and also rating calculations of WPHE with determined parameters of its construction. The validity of the proposed Equations and developed mathematical model is confirmed by comparison with the data of tests on WPHE installed in ammonia synthesis column at industrial enterprise of ammonia production. WPHE was operating in existing synthesis column of ammonia unit instead shell-and-tube heat exchanger. The construction of WPHE and the results of the tests are discussed. The use of WPHE instead shell-and-tube unit enable to cut down the volume occupied by heat exchanger in high pressure shell of ammonia synthesis column and allows increase of the volume of catalyst. It leads to 15 % rise of ammonia output.Документ Mathematical model of plate heat exchanger for utilisation of waste heat from condensable gaseous streams(The Italian Association of Chemical Engineering, 2018) Kapustenko, Petro Oleksiyovych; Demirskiy, O. V.; Tovazhnyanskyy, Leonid Leonidovich; Klemeš, Jiří Jaromír; Vasilenko, O. A.; Kusakov, S. K.; Arsenyeva, Olga Petrovna; Khusanov, A. E.The mathematical model of vapour condensation from the mixture with noncondensing gas in Plate Heat Exchanger (PHE) channels is presented. The model accounts for the change of process parameters along the heat transfer surface and local features of heat and mass transfer processes in PHEs channels with plates of different corrugations geometry. It consists of the system of ordinary differential equations with considerably nonlinear right parts. The software for its solution by finite difference method is developed. The validity of the model is confirmed by comparison with the experiment for steam-air mixture condensation in a PHE channel sample.Документ Mathematical Modelling and Optimal Design of Plate-and-Frame Heat Exchangers(The Italian Association of Chemical Engineering, 2009) Arsenyeva, O. P.; Tovazhnyanskyy, Leonid Leonidovich ; Kapustenko, P. O.; Khavin, G. L.The optimal design for multi-pass plate-and-frame heat exchanger with mixed grouping of plates is considered. It is formulated as the mathematical problem of finding the minimal value for implicit nonlinear discrete/continues objective function with inequality constraints. The optimizing variables include the number of passes for both streams, the numbers of plates with different corrugation geometries in each pass, the plate type and size. To estimate the value of objective function in a space of optimizing variables the mathematical model of plate heat exchanger developed. To account for thermal and hydraulic performance of channels between plates with different corrugation patterns, the exponents and coefficients in formulas to calculate heat transfer coefficients and friction factors used as model parameters. The procedure and software for numerical experiment to identify model parameters by comparing the calculation results with those obtained with free available in web computer programs of plate manufacturers is developed. The sets of such parameters are obtained for a number of industrially manufactured plates. The described approach implemented as software for plate heat exchangers calculation. Two case studies results discussed.Документ Mathematical modelling of the thermal and hydraulic behaviour of plate heat exchanger in the fouling conditions(The Italian Association of Chemical Engineering, 2018) Kapustenko, Petro Oleksiyovych; Demirskiy, O. V.; Tovazhnyanskyy, Leonid Leonidovich; Klemeš, Jiří Jaromír; Matsegora, O. I.; Arsenyev, Pavlo Yurievich; Arsenyeva, Olga PetrovnaThe mathematical model of Plate Heat Exchanger (PHE) subjected to fouling is proposed. It is represented by the system of ordinary differential equations. The model is accounting for the distribution of process parameters along the PHE channel that allows predicting fouling development in time at different locations along the channel length. The development of the fouling deposit is accounted with the fouling model presented by the equation in dimensionless form. The relative influence of different terms is characterized by empirical coefficients which can be identified with the data of monitoring the PHE thermal and hydraulic performance. The model allows also the prediction of pressure drop variation in PHE with the development of fouling deposition layer and respective reduction in channels cross-section area. The application of the model and its accuracy is demonstrated with two case studies considering the monitoring of PHEs thermal and hydraulic performance in the industry at sugar factory and in District Heating system.Документ Mitigation of Fouling in Plate Heat Exchangers for Process Industries(The Italian Association of Chemical Engineering, 2012) Kapustenko, P. O.; Tovazhnyanskyy, Leonid Leonidovich ; Arsenyeva, O. P.; Yuzbashyan, A. P.Among different methods for mitigation of fouling the use of enhanced heat transfer surfaces is one of the major categories. Heat transfer enhancement is one of the main features of Plate Heat Exchanger (PHE) and mitigation of fouling render even more advantages to the use of this type of heat transfer equipment in different applications at process industries. In present study the period of fouling deposit formation in PHEs and influencing it factors are investigated. To estimate development of fouling thermal resistance with time the Equation is proposed. The pictures of fouling deposit distribution along the plate of PHE for fresh water heating are analyzed. The conclusion is, that for scaling fouling there exist some threshold conditions on wall shear stress, wall temperature and salt content, after which fouling deposition starts. The expression of fouling deposition rate proposed for the tubes with heat transfer enhancement by Yang and Crittenden is used. Comparison with available in literature experimental data have shown good agreement with proposed model, when one its parameter is adjusted. For certain cooling water circuit of a big industrial enterprise this parameter can be determined by data about fouling in one heat exchanger. After that the model can be used for prediction of cooling water fouling development with a time in all heat exchangers of this circuit.