Кафедри
Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393
Переглянути
9 результатів
Результати пошуку
Документ Determination of kinetic characteristics of heat and mass exchange in a column heat exchanger with direct phase contact(РС Tесhnology сеntеr, 2024) Tseitlin, Musii; Shkop, Andrii; Shestopalov, Oleksіi; Raiko, Valentina; Ponomarova, NataliiaОб’єктом дослідження були процеси тепломасообміну в колонному теплообміннику з безпосереднім контактом фаз. Досліджувана проблема пов’язана з необхідністю визначення оцінок кінетичних характеристик теплообміну при концентруванні розчинів у контактному теплообміннику, оснащеному двопоточними тарілками. Зокрема, передбачалося, що визначення впливу швидкості газу в апаратові і щільності зрошення тарілок рідиною, а також геометрії тарілок, на кінетичні коефіцієнти дасть змогу виявити закономірності теплообміну і масообміну між рідиною і контактуючим з нею повітрям в колонному апарату. Визначено, що для збільшення інтенсивності масообміну в газі та теплообміну в рідині необхідно збільшувати значення швидкості газу та щільності зрошення. Тоді швидкість газу та щільність зрошення приблизно однаково впливають на інтенсивність масообміну в газі та теплообміну в рідині. При дослідженні впливу геометрії тарілки на кінетичні коефіцієнти тепловіддачі в рідині та масообміну в газі встановлено, що величина частки вільного перерізу тарілки має вирішальний вплив на значення розглянутих кінетичних коефіцієнтів. Отримано узагальнене рівняння, яке дає змогу не тільки розрахувати коефіцієнт передачі ентальпії при взаємодії розчину хлориду натрію з повітрям, а й визначити лімітуючу стадію цього процесу. Отримані результати можуть бути використані в розробці установки концентрування гарячого розчину хлориду натрію випаровуванням води при продуванні повітрям в контактному теплообміннику. Це може дати змогу отримання кристалічного хлориду натрію з використанням вторинних енергоресурсів та інших нетрадиційних джерел теплової енергії.Документ Defining features in the kinetics of sodium carbonate-bicarbonate solution carbonization and the quality of the resulting sodium bicarbonate crystals(Технологический центр, 2021) Porokhnia, Mykola; Tseitlin, Musii; Bukhkalo, Svitlana; Panasenko, Vladimir; Novozhylova, TetianaThis paper reports a study into the influence of temperature and gas consumption on the carbonization kinetics (saturation with carbon dioxide) of sodium carbonate-bicarbonate solution. The study also examined the quality and speed of crystal formation in this process. This research is predetermined by the environmental problems faced by modern enterprises that produce purified sodium bicarbonate – an insufficient degree of carbonization and, as a result, excessive air pollution with carbon dioxide, which did not participate in the reaction during the process. This study addresses these particular issues. As a result of using specialized laboratory equipment, it was found that an increase in the absorbent temperature from 79 to 85 °C leads to a decrease in the maximum degree of carbonization of the solution from 64 to 59 %. In contrast, the quality of the resulting sodium bicarbonate crystals improves but only in the range from 79 to 82 °C. With a further increase in temperature, the quality stabilizes. It is shown that the carbonization rate increases with increasing specific consumption of the absorbent (carbon dioxide) and is characterized by a negative correlation with the value of oversaturation of the absorbent in terms of NaНCO₃. The quality of sodium bicarbonate crystals decreases with increasing gas velocity. Thus, it was reasonable to assume that the established dependence of the kinetics of carbonization of Na₂CO₃ and NaНCO₃ solution on the gas velocity in the apparatus is explained by the inhibition of СО₂ absorption, which is caused by the diffusion resistance of sodium bicarbonate crystallization. To improve the quality of crystals and the productivity of carbonization by reducing the supersaturation in terms of NaНCO₃, it is recommended to introduce a seed crystal in the zone of binding of crystals in the carbonization columns.Документ Optimization of floccular cleaning and drainage of thin dispersed sludges(Scientific Route, Estonia, 2020) Shestopalov, Oleksii; Briankin, Oleksandr; Rykusova, Nadegda; Hetta, Oksana S.; Raiko, Valentina; Tseitlin, MusiiThe efficiency of solid phase retention and dehydration of finely dispersed products of a coal processing plant and a metallur gical enterprise on the module for cleaning and dewatering sludge is investigated. A technique for selecting the operating parameters of equipment based on the determination of the strength criterion of flocs is proposed. A methodology for technological tests has been developed to control the flocculation process and optimize the flow of flocculant depending on the concentration of the solid phase. Industrial tests on the module for wastewater treatment and sludge dewatering using flocculants proved the effectiveness of the developed methodology. It is shown that the conditions for conducting tests on flocculation should correspond to the operating conditions of the circuit apparatus for cleaning and dewatering sludge. These conditions include sludge performance, sludge flow rate in the cross section of pipes and apparatuses, and the flow time from the flocculator to the centrifuge. During the testing of the Module, the solids retention efficiency of 97–99 % was achieved with the strength criteria of flocs in front of a centrifuge of 2–2.5 mm/s. The conditions for the high efficiency of the apparatus chain are the optimization of the aggregation process itself. It is revealed that for the formation of strong flocs it is necessary to regulate the concentration of the solid phase. For coal sludge, the concentration of the solid phase before the flocculant is fed must be maintained no higher than 50–60 g/l, and for gas treatment sludge – no higher than 20–25 g/l. Correction of the concentration of sludge before the flocculator is possible by diluting it with clarified water to the optimum concentration for aggregation. It is found that the moisture content of the sediment and the efficiency of the retention of the solid phase depend on the strength criterion of the flocs. Therefore, the optimization of the flocculant flow rate is possible by controlling and the residual floccule deposition rate after mechanical action in front of the dewatering equipment. The flocculant flow rate must be adjusted depending on the concentration of the solid phase in the sludge to achieve the desired criterion for the strength of the flocs.Документ Studying patterns in the flocculation of sludges from wet gas treatment in metallurgical production(PC Technology center, 2019) Shestopalov, Oleksii; Briankin, Oleksandr; Tseitlin, Musii; Raiko, Valentina; Hetta, Oksana S.The influence of a solid phase concentration in the model sludges of wet gas purification, as well as the flocculant consumption, on a change in the solid phase sedimentation rate and the strength of floccules has been examined. This is important because fluctuations in the solid phase concentration in waste water represent an uncontrolled process that significantly affects the kinetics of the solid phase sedimentation and leads to an increase in the flocculant consumption. We have proposed a procedure for determining the sedimentation rate of the flocculated sludge and the strength of floccules following the hydromechanical influence, which takes into consideration the solid phase concentration and the flocculant consumption. The study was carried out on model waste water, synthesized by mixing the dust from dry gas purification at actual production site with water. It has been determined that the solid phase concentration affects the rate of floccule deposition. It has been established that the optimum conditions for aggregate formation within a given model system are observed at the solid phase concentration in the interval 8–12 g/l. Increasing the solid phase concentration above 16 g/l decreases the floccule sedimentation rate disproportionately to the flocculant concentration. It is possible to reduce flocculant consumption and to optimize its dosage by carrying out a cleaning process taking into consideration the specified patterns. It was established that the hydromechanical influence on aggregates exerts the destructive effect, whose degree depends on the solid phase concentration. In particular, increasing the rate of fluid motion leads to greater damage to floccules than increasing the time for a less intense exposure. The way to minimize the destructive effect on floccules could be lowering the suspension transportation speed resulting from a decrease in the installation performance or through the increased cross-section of the channel (a pipeline). An increase in the solid phase concentration of the model system above 16 g/l is accompanied by a significant reduction in the strength of floccules. Therefore, when designing wastewater treatment plants that utilize flocculants, it is necessary to provide optimum conditions for aggregation and to minimize the hydromechanical effects on floccules by lowering the velocity of fluid motion.Документ Ratio between heat and mass transfer when concentrating the solution in a cooling tower(Lviv Polytechnic National University, 2019) Tseitlin, Musii; Raiko, ValentinaThe ratio between the intensity of the mass transfer in gas and the heat transfer in liquid during the evaporative solution concentration has been studied. It was determined that the share of liquid resistance in the total resistance to enthalpy transfer increases in the temperature range from 30 to 50°C by almost 2 times, and reaches 40 %. The technique has been developed for the separate determination of the mass transfer coefficients in gas and heat transfer in liquid.Документ Analysis of ways reducing drilling waste in oil and gas production influencing on natural environment(UNIVERSITAS Publishing, Romania, 2019) Shestopalov, Oleksii; Rykusova, N. I.; Tseitlin, Musii; Raiko, ValentinaДокумент A study of the flocculs strength of polydisperse coal suspensions to mechanical influences(Scientific Route, 2017) Shkop, Andrii; Tseitlin, Musii; Shestopalov, Oleksii; Raiko, ValentinaThe effect of the concentration and disperse composition on the flocculation strength to mechanical influence is investigated. It is found that the residual rate of floccules sedimentation after the mechanical influence at a constant rate of flocculant has a maximum value at a concentration of solids in the slime in the range of 7–30 g/dm3. The best results are obtained in all the experiments at a solids concentration of 10 g/l. It is found that at a concentration up to 7 g/l and more than 30 g/l, the floccules is formed. They have the lowest residual rate after mechanical influences. With increasing content of the solid fraction of 40–100 microns over 15 %, the strength of floccules increases. They retain their shape and relatively high sedimentation rate even after mechanical influence. The obtained data allow to recommend correction of the slime composition before flocculant injection both the concentration close to the optimum, and the content of size fraction of 40–100 mm more than 15 %.Документ A study of wastewater treatment conditions for the poultry meat processing enterprise(Технологічний центр, 2018) Makhlay, Konstantyn; Tseitlin, Musii; Raiko, ValentinaFor the local treatment of wastewater of food industry enterprises, physicochemical treatment methods are widely used, which, with properly selected reagents and their doses, allow achieving high treatment efficiency. At the same time, doses of reagents and conditions for their use can differ sharply between enterprises, therefore the regularities of the treatment process must be studied at a particular drain. In the paper, the regularities of the process of wastewater coagulation by coagulants and flocculants of different chemical composition are examined on the example of the wastewater of the turkey meat processing enterprise. The regularities of the process of wastewater coagulation in a wide range of pH values of the medium are studied. It is experimentally determined that the optimum pH of the medium for the use of polyaluminum chloride is in the range 5.9÷6.4, iron chloride 6.2÷6.7, iron sulfate 5.1÷5.7. The regularities of the effect of the coagulant dose on the efficiency of suspended solids removal from wastewater and color reduction are established. Based on the data obtained, the most optimum doses of coagulants are determined. The rational dose of polyaluminum chloride was 140 mg/l, iron sulfate – 110 mg/l and iron chloride – 80 mg/l. The regularities of the process of wastewater flocculation with the use of flocculants of different charges and molecular weight are investigated. The most effective types of flocculants are determined, and optimum reagent doses are established. The rational conditions for physicochemical wastewater treatment using coagulants and flocculants are determined. The obtained data make it possible to optimize the operation of local treatment facilities of the poultry processing enterprise: to increase performance, as well as to reduce operating costs. The selected binary combinations of reagents allow achieving the efficiency of suspended solids removal of 99.4 % and color reduction – 82.4 %.Документ Study of the strength of flocculated structures of polydispersed coal suspensions(Технологічний центр, 2017) Shkop, Andrii; Tseitlin, Musii; Shestopalov, Oleksii; Raiko, ValentinaThe influence of concentration, dispersed composition and degree of thickening of the flocculated slime on the strength of floccules was studied. It was revealed that for the formation of durable aggregates of polydispersed coal slime it is recommended to apply the combination of the non-ionogenic and anionogenic flocculant in the ratio of 20:80 % respectively. It was established that the residual sedimentation rate of floccules after mechanical influence at the constant consumption of the flocculant has the greatest value at the concentration of solid phase in slime of 10–30 g/dm3. With an increase in the content of the portion of solid phase with coarseness of more than 40 µm, the strength of floccules increases to the larger degree than the influence of the initial concentration. This makes it possible to recommend the correction of the slime composition not only by the concentration, but also by the content of medium grade of more than 15–20 %. It was shown that with an increase in the degree of thickening of more than 140–150 g/l the resistance of aggregates to mechanical influence substantially decreases due to an increase in pseudo-plastic properties of flocculated slime.