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1

The simple network-based measuring system for improving the evaporation estimation

Dlouhá Dagmar, Pospíšil Lukáš, Dubovský Viktor

Production Engineering Archives

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2023

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Vol. 29, Iss. 3

328-336

EN

This paper presents a novel method for measuring the data for evaporation estimation as the key ingredient for the final decision of the reclamation form in the area of the Most Basin. The area has been intensively mined for many decades, resulting in significant landscape devastation, loss of natural habitats, and negative environmental impact. Currently, it is assumed that by 2050, three large-scale reclamation projects will be implemented in the area and it is necessary to decide which form of reclamation to choose. Whether to build lakes according to the currently valid rehabilitation and reclamation plan or to leave the area of the quarries in succession with the support of spontaneous inflow of water up to a naturally sustainable water level. Whether the first or second option is approved, or a combination of both, the prediction of evaporation from the free water surface will always be of great importance. To deal with this goal, the available meteorological data must be combined with a suitable calculation method. In our work, we suggest utilizing a measuring network of meteorological devices that describe the character of the weather in a given area of interest in a long-term time series. Together with the state-of-the-art calibration of models for calculating evaporation, the measurement network helps to provide more accurate evaporation data for a given area. Based on the analysis of research results, it will be possible to choose a specific right decision and thus contribute to the long-term sustainability of these reclamations.

2

A data-driven approach to predict hydrometeorological variability and fluctuations in lake water levels

Tan Kesgin Remziye I., Demir Ibrahim, Kesgin Erdal, Abdelkader Mohamed, Agaccioglu Hayrullah

Journal of Water and Land Development

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2023

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no. 58

158--170

EN

Beyşehir Lake is the largest freshwater lake in the Mediterranean region of Turkey that is used for drinking and irrigation purposes. The aim of this paper is to examine the potential for data-driven methods to predict long-term lake levels. The surface water level variability was forecast using conventional machine learning models, including autoregressive moving average (ARMA), autoregressive integrated moving average (ARIMA), and seasonal autoregressive integrated moving average (SARIMA). Based on the monthly water levels of Beyşehir Lake from 1992 to 2016, future water levels were predicted up to 24 months in advance. Water level predictions were obtained using conventional time series stochastic models, including autoregressive moving average, autoregressive integrated moving average, and seasonal autoregressive integrated moving average. Using historical records from the same period, prediction models for precipitation and evaporation were also developed. In order to assess the model’s accuracy, statistical performance metrics were applied. The results indicated that the seasonal autoregressive integrated moving average model outperformed all other models for lake level, precipitation, and evaporation prediction. The obtained results suggested the importance of incorporating the seasonality component for climate predictions in the region. The findings of this study demonstrated that simple stochastic models are effective in predicting the temporal evolution of hydrometeorological variables and fluctuations in lake water levels.

3

Evaluation of Evapotranspiration and Performance of Emerging Plants: Case of Cyperus papyrus and Typha latifolia

Benrahmane Loubna, Mouhir Latifa, Laaouan Mohamed, El Hafidi Mustapha, Saafadi Laila

Journal of Ecological Engineering

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2023

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Vol. 24, nr 11

257--267

EN

The treatment of wastewater in small rural settlements requires special attention in the choice of the purification technique to be used, insofar as experience has shown that the technologies initially developed for the urban environment do not prove to be as effective for the rural environment. The current trend tends towards autonomous systems. Among these systems are Floating treatment wetlands. The objective of this study was to evaluate the evapotranspiration and the performances of two emerging plants; Cyperus papyrus and Typha latifolia. The experimental device was composed of three test tanks whose dimensions were: length = 1 m, width = 1 m and water height = 0.85 m – two tanks with emerging plants (Cyperus papyrus and Typha latifolia) and a control tank without vegetation. The monitoring of the evolution of plant evapotranspiration and the evaporation of the control tank for different periods and temperatures showed that the volumes of water lost were respectively for Cyperus papyrus, Typha latifolia and control tank: (1) 130 liters, 230 liters and 5 liters for two days at an average temperature of 26.3 °C; (2) 125 liters, 150 liters and 0 liters for two days at an average temperature of 26.7 °C; (3) 240 liters, 280 liters and 5 liters for three days at an average temperature of 27.3 °C; (4) 140 liters, 260 liters and 10 liters for two days at an average temperature of 26 °C; (5) 140 liters, 240 liters and 5 liters for two days at an average temperature of 27.3 °C; (6) 260 liters, 550 liters and 10 liters for four days at an average temperature of 28.6 °C. It turned out that the presence of plants as well as the temperature and the retention time in the tanks have a impact on the loss of water and more precisely those with emerging macrophytes. The present study has shown that the floating treatment wetlands planted with Cyperus papyrus and Typha latifolia can be used for wastewater treatment. Indeed, the removal efficiency in terms of COD, BOD5 and SS were respectively: 76%, 75.3% and 95.90% for Cyperus papyrus and 70.45%, 66.5% and 93.70% for Typha latifolia.

4

Results of Mathematical Modeling of Evaporation Process the Drops of Sulfuric Acid in the Gas Flow

Khimka Uliana, Helesh Andriy, Bukliv Roksoliana, Śniadkowski Mariusz

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

41--47

EN

The processes of concentration of dilute solutions of sulfuric acid (H2SO4), in particular hydrolytic sulfuric acid for the production of pigment titanium (IV) oxide, were analyzed. It is proposed to concentrate solutions of Н2SO4 by evaporation in direct contact of acid droplets with hot industrial exhaust gases. The mathematical model of the evaporation of Н2SO4 drops in a hot gas stream, which used for the calculations, makes it possible to calculate the mass, temperature, velocity, and coordinates of the drop at any time with sufficient accuracy. However, the calculations are difficult, cumbersome and require multiple processing of large data sets. Therefore, the aim of the article was to approximate the calculated technological parameters of sulfuric acid droplet evaporation by obtaining simple mathematical dependencies. The mathematical dependences of the mass transfer coefficient and the distance traveled by a drop of Н2SO4 during evaporation on air temperature and drop diameter were obtained. It has been established that technologically expedient evaporation of Н2SO4 drops with a diameter of ≤ 0,5·10-3 m in traditional devices leads to significant droplet loss, increased corrosion of equipment, etc. So, in order to practically implement the technology of evaporation of HSA solutions with industrial exhaust gases, it is necessary to change the technological mode of operation of the evaporator and the design of the main device. It is proposed to use the obtained results to study the methods of intensification of the evaporation process, selecting a modern mass transfer apparatus, developing a technology for utilizing hydrolytic sulfuric acid and producing pigment titanium (IV) oxide.

5

Thermal and physical properties and heat-mass transfer processes of drying pumpkin seeds

Paziuk Vadim, Snezhkin Yurii, Dmytrenko Natalia, Ivanov Sergiu, Tokarchuk Oleksiy, Kupchuk Ihor

Przegląd Elektrotechniczny

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2022

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R. 98, nr 7

154--157

EN

We have investigated pumpkin seed heat capacity influenced by the two factors of the heat agent temperature and the moisture content of the material. The difference between the heat of evaporation when drying pumpkin seeds in a differentiated microcalorimeter DMKI 01 from the tabular value is 6%. Increasing the temperature of the heat agent from 40 to 60°C reduces the drying process by 8 times, but the most appropriate is the drying mode at 40°C, under which the germination of pumpkin seeds is 98%. The study of heat and mass transfer during drying shows that active heat up process takes place at the beginning, then there is an intensive moisture evaporation from the material as evidenced by the value of the Rehbinder test, which is close to zero.

PL

Badano pojemność cieplną pestek dyni, na którą wpływają dwa czynniki: temperatura czynnika grzewczego oraz wilgotność materiału. Różnica pomiędzy ciepłem parowania podczas suszenia pestek dyni w zróżnicowanym mikrokalorymetrze DMKI 01 od wartości tabelarycznej wynosi 6%. Podwyższenie temperatury czynnika grzewczego z 40 do 60°C skraca proces suszenia 8-krotnie, ale najbardziej odpowiedni jest tryb suszenia w 40°C, w którym kiełkowanie pestek dyni wynosi 98%. Z badań wymiany ciepła i masy podczas suszenia wynika, że na początku zachodzi proces aktywne(go nagrzewania, następnie następuje intensywne odparowywanie wilgoci z materiału, o czym świadczy bliska zeru wartość testu Rehbindera.

6

Oznaczanie wilgoci w biomasie metodą miareczkowania kulometrycznego Karla Fischera

Jędrychowska Sylwia, Kowalczyk Anna

Nafta-Gaz

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2022

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R. 78, nr 5

393--400

PL

W artykule przedstawiono prace nad wykorzystaniem metody miareczkowania kulometrycznego Karla Fischera z odparowaniem do oznaczania zawartości wody w biomasie. Przeprowadzono badania sześciu rodzajów próbek biomasy roślinnej: zmielonej kawy otrzymanej jako odpad po zaparzeniu, słomy pszenicznej, siana, łupin orzecha włoskiego oraz zrębków drewna leszczynowego i świerkowego. Wykonano badania zawartości wody we wszystkich pozyskanych produktach i porównano wyniki z wynikami otrzymanymi dwiema innymi metodami stosowanymi standardowo do badania wilgoci w biomasie, tj. metodą wagosuszarkową i destylacyjną. Stwierdzono, że wszystkie metody wykazały dobrą zgodność w zakresie wyników uzyskanych dla przebadanych próbek. Najmniej przydatna okazała się metoda destylacyjna, której rezultaty najbardziej odbiegały względem pozostałych metod. Wykonanie analizy tą techniką wymaga długiego czasu, jest ona dość pracochłonna i niezautomatyzowana. Najszybszą techniką jest metoda wagosuszarkowa, ale cechuje ją mniejsza precyzja w stosunku do metody kulometrycznej. Wyniki otrzymane tą metodą mogą być zawyżone ze względu na to, że miarą zawartości wody w badanej próbce jest ubytek masy, który może być związany nie tylko z obecnością wody, ale także z innymi lotnymi substancjami uwalnianymi w trakcie badania. Metoda miareczkowania kulometrycznego Karla Fischera jest natomiast metodą selektywną i podczas analizy oznaczana jest tylko woda odparowywana z próbki, nawet gdyby z próbki uwalniały się jeszcze inne substancje lotne w warunkach badania. Metoda miareczkowania kulometrycznego Karla Fischera z odparowaniem próbki w piecyku wykazała się największą precyzją. Jest łatwa w wykonaniu i zautomatyzowana. Stwierdzono, że metoda ta może być z powodzeniem stosowana w badaniu biomasy. Zawartość wody we wszystkich pozyskanych próbkach biomasy wahała się w przedziale od 8% do 10,5% (m/m). W celu zbadania możliwości oznaczenia zawartości wody w szerszym zakresie pomiarowym próbki biomasy suszono w suszarce laboratoryjnej w ciągu 4 godzin w temperaturze 105°C oraz dodatkowo przygotowano próbki modelowe o różnej zawartości wody z wykorzystaniem zmielonej kawy jako matrycy. Na przygotowanych próbkach wykonano badania wilgoci metodą miareczkowania kulometrycznego Karla Fischera z odparowaniem. Przeprowadzone badania potwierdziły, że metoda ta świetnie nadaje się do badania próbek biomasy. Charakteryzuje się bardzo dobrą powtarzalnością w badanym zakresie od 0,7% do 75% (m/m).

EN

The article presents works on the use of coulometric Karl Fischer titration with evaporation for determining water content in biomass. Six types of plant biomass samples were tested: ground coffee obtained as brewed waste, wheat straw, hay, walnut shells and hazel and spruce wood chips. Tests of water content in all obtained products were carried out and their results were compared with two other methods used as standard for biomass moisture testing, i.e. by using a drying balance method and the distillation method. All the methods were found to be in good agreement with the results obtained for the samples tested. The distillation method turned out to be the least useful, as it gave results that differed most from the other methods. The analysis time using this technique is long, it is quite laborious to perform and is not automated. The fastest technique is the method utilizing a drying balance, but it is less precise than the coulometric method. The results obtained with this method may be overestimated as the measure of water content in the tested sample is the loss of mass, which may be related not only to the presence of water, but also to other volatile substances released during the test. On the other hand, the coulometric Karl Fischer titration method is selective and only the water evaporated from the sample is determined during the analysis, even if other volatile substances are released from the sample under the test conditions. The coulometric Karl Fischer titration method with sample evaporation in an oven showed the best precision. It is easy to make and automated. It was found that this method can be successfully used in biomass research. The water content in all obtained biomass samples ranged between 8 and 10.5% (m/m). In order to investigate the possibility of determining the water content in a wider measuring range, the biomass samples were dried in a laboratory dryer for 4 hours at 105°C, and additionally, model samples with different water content were prepared using ground coffee as a matrix. The prepared samples were tested with coulometric Karl Fischer titration with evaporation method. The conducted research confirmed that the method of coulometric Karl Fischer titration with evaporation is perfect for testing biomass samples. It is characterized by a very good repeatability in the tested range, from 0.7 to 75% (m/m).

7

Evaporation of Zinc in an Argon - Hydrogen Mixture

Matuła Tomasz

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

885--888

EN

Many modern processes for the production and casting of metals and their alloys are carried out in protective gas atmospheres, which protect them, for example, from oxygen pollution. This applies, for example, to titanium, magnesium or aluminum alloys. Most liquid alloys are comprised of constituents that differ in vapor pressures, resulting in harmful phenomenon during melting due to evaporation of some of its components. This harmful process may be limited by the selection of a suitable gas atmosphere in which the liquid metal treatment process is carried out. In the paper, results of study on the impact of the type of gas atmosphere on the rate of evaporation of zinc in argon - hydrogen mixtures are presented. It should be noted that such mixtures are used, for example, in metal welding processes, in which it is also possible to evaporate a component of the so-called liquid metal pool. The research results showed that the rate of zinc evaporation increases with the increase of hydrogen content in the gas atmosphere.

8

Optymalizacja warunków oznaczania wody metodą miareczkowania kulometrycznego z odparowaniem dla olejów smarowych

Jędrychowska Sylwia

Nafta-Gaz

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2021

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R. 77, nr 7

480--489

PL

Wiedza o zawartości wody w produktach naftowych, między innymi olejach smarowych, dodatkach oraz różnych innowacyjnych produktach, jest istotna z punktu widzenia ich wytwarzania, zakupu czy sprzedaży ze względu na wpływ na ich jakość i charakterystykę działania. W przypadku olejów smarowych obecność wody może stanowić przyczynę przedwczesnej korozji i zużycia, powstawania osadów, co prowadzi do ograniczenia smarowania i przedwczesnego zatkania filtrów, osłabienia działania dodatków czy niepożądanego wzrostu bakterii. W artykule przedstawiono prace nad dobraniem optymalnych warunków oznaczania zawartości wody metodą miareczkowania kulometrycznego Karla Fischera z odparowaniem w olejach smarowych. Badania przeprowadzono z wykorzystaniem kulometru z celą miareczkową bez diafragmy firmy Metrohm model 917 Coulometer wraz automatycznym podajnikiem próbek wyposażonym w komorę grzejną 885 Compact Oven Sample Changer. Do badań wytypowano różne rodzaje olejów smarowych, a mianowicie oleje silnikowe o różnej klasie lepkości (5W-40, 10W-40, 15W-40, 5W-30), olej przekładniowy, olej hydrauliczny, olej turbinowy, olej bazowy oraz płyn hydrauliczny. Wszystkie wytypowane próbki olejów smarowych badano w czterech różnych warunkach pomiarowych: 110°C i 20 ml/min; 150°C i 50 ml/min, 180°C i 50 ml/min oraz 150°C i 70 ml/min. Stwierdzono, że w przypadku wszystkich wyżej wymienionych olejów smarowych najlepsze wyniki uzyskano przy ustawieniu temperatury pieca na 150°C i przy przepływie gazu nośnego wynoszącym 50 ml/min lub 70 ml/min. Określono wpływ różnych czynników, takich jak naważka próbki, temperatura pieca, prędkość przepływu gazu nośnego, na przebieg badania oraz szybkość analizy. Zwiększony przepływ gazu nośnego do 70 ml/min nie powoduje skrócenia czasu analizy. W niektórych przypadkach wzrost temperatury pieca może przyspieszyć szybkość analizy, ale jest to dość ryzykowne dla niektórych próbek, które w tej temperaturze ulegają rozkładowi. W związku z tym bezpieczniej jest prowadzić badanie w temperaturze pieca 150°C. Największy wpływ na szybkość analizy ma odpowiedni dobór naważki próbki poddanej analizie. W zależności od zawartości wody w badanej próbce należy dobrać odpowiednią naważkę próbki. Powinna być ona na tyle mała, aby nadmiernie nie wydłużać analizy, ale także na tyle duża, żeby ilość odmiareczkowanej wody była przynajmniej dwukrotnie większa niż w ślepej próbie.

EN

The knowledge of the water content of various petroleum products, including lubricating oils, additives and various innovative products, is important from the point of view of manufacturing, purchasing or selling them, due to the impact on their quality and performance characteristics. In the case of lubricating oils, the presence of water can lead to premature corrosion and wear, the formation of deposits, which leads to reduced lubrication and premature clogging of filters, reduced action of additives or undesirable bacterial growth. The article presents the study on the selection of optimal conditions for the determination of water content by coulometric Karl-Fischer titration with evaporation in lubricating oils. The tests were carried out using a coulometer with a titration cell without a diaphragm by Metrohm, 917 Coulometer model with an automatic sample feeder equipped with a heating chamber 885 Compact Oven Sample Changer. Various types of lubricating oils were selected for testing, namely engine oils of different viscosity classes (5W/40, 10W/40, 15W/40, 5W/30), gear oil, hydraulic oil, turbine oil, base oil and hydraulic fluid. All selected samples of lubricating oils were tested in four different measuring conditions: 110°C and 20 ml/min; 150°C and 50 ml/min, 180°C and 50 ml/min and 150°C and 70 ml/min. It was found that for all the lubricating oils, the best results were obtained with a furnace temperature setting of 150°C and a carrier gas flow of 50 ml/min or 70 ml/min. The influence of various factors, such as the sample weight, the furnace temperature, the carrier gas flow velocity on the test course and the analysis speed, was determined. Increased carrier gas flow of up to 70 ml/min does not shorten the analysis time. In some cases, an increase in the oven temperature may speed up the analysis, but this is quite risky for some samples that decompose at given temperature. It is therefore safer to conduct the test at an oven temperature of 150°C. The speed of analysis is most influenced by an appropriate selection of the sample quantity under analysis. Depending on the water content in the tested sample, the appropriate sample weight should be selected. It should be small enough not to excessively extend the analysis, but also large enough that the amount of titrated water is at least twice as large as in the blank.

9

The Evaporation Estimation on Lake Most

Dlouhá Dagmar, Dubovský Viktor, Pospíšil Lukáš

Multidisciplinary Aspects of Production Engineering

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2021

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Vol. 4, Iss. 1

221--231

EN

After finishing the mining process, the best way to deal with the residual of open-cut coal mines in the north-western region of the Czech Republic has been proposed to be hydric recultivation. The area of our study is the first artificial Lake Most (formerly known as Ležáky-Most coal quarry) finished in 2014 and opened to the public in 2020 for recreational purposes. Since the lake is a closed system without natural inflow and outflow, the prediction of evaporation plays a crucial role in the securitization of long-term sustainability based on the capability of keeping the stable level of a dimension of the final water level. In this paper, we use the historical data consisting of the altitude of the lake level, its area, the perimeter of the shoreline, and especially the volume of refilled water. These data are compared against the computational methods; namely, the Penman-Monteith Equation and Hargreaves-Samani model calibrated by the method proposed in our previous work.

10

Long-Term Retardation of Water Evaporation by Ultra-Thin Layers of Polydimethylsiloxanes in the Indoor Conditions

Zhuk Volodymyr, Rehush Andriy, Burchenya Sofiya, Hrytsiv Oleh

Journal of Ecological Engineering

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2021

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Vol. 22, nr 8

33--40

EN

Global climate change is causing water imbalances in many regions of the world to exceed evaporation over rainfall, leading to negative environmental consequences and economic losses. An effective way to reduce the water loss due to evaporation from the free surface of water bodies is the use of ultra-thin surface films of special additives. Insufficient stability and significant cost of additives based on fatty alcohols (hexadecanol, octadecanol and their mixtures) necessitate searching for new effective and more economical additives to reduce the water loss due to evaporation. A series of long-term (84 day) experimental studies of the effect of ultra-thin layers of polydimethylsiloxanes PDMS100 and PDMS-200 with a thickness of 1 μm on the rate of evaporation of water from the free surface was conducted under the indoor laboratory conditions. Both the dynamics of change in time of daily values of the effect of evaporation retardation by PDMS films, and total effect from the beginning of experiment were obtained. The maximum daily effects of evaporation retardation were obtained on the 6th day of the study; they are 39.5% for the PDMS-200 film and 32.9% for the PDMS-100 film, respectively. Linear correlations are obtained between the values of the mass transfer coefficient and the free surface temperature for water without additives, as well as for the same free surfaces with ultra-thin PDMS films. Overall integral efficiency of evaporation retardation by the PDMS-200 film with a thickness of 1 μm for 84 days was equal to 17.2%, while for the PDMS-100 film of the same thickness a reduction of evaporation by 5.7% was obtained. Due to the long-term activity, ultra-thin films of polydimethylsiloxanes, especially PDMS-200, can be a profitable alternative to the use of monolayers based on fatty alcohols.

11

Assessment of the Influence of Evaporation and Evapotranspiration on the Volume of Sludge Accumulation in the Sludge Drying Beds

Velychko Svitlana, Dupliak Olena

Journal of Ecological Engineering

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2021

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Vol. 22, nr 2

63--69

EN

At present, the sludge drying beds of the Kyiv wastewater treatment plants are operated as a sludge accumulator in an emergency mode, practically without free volume. The purpose of the work was to determine the equation for the evaporation losses calculation from sludge drying beds and the required free volume for sludge accumulation for the next 7 years. The required free volume was calculated using the water budget method which takes into account evaporation from the water surface and evapotranspiration during the vegetation. The total losses from sludge drying beds is 1076 mm/year in normal year and is 920 mm/year in a cold year. The required free volume was calculated considering the trend of increasing average temperature over the last decade and considering the significant environmental risk. A correction was made for one unfavourable year with cold summer and warm winter and an additional rain rate of 1% probability. The additional free volume required is 3.24 million m3 for 7 years if all three sludge drying beds are operated.

12

Specification of the climate character in the study area of projected hydric reclamation

Dlouhá Dagmar, Dubovský Viktor

Inżynieria Mineralna

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2021

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no. 1

75--79

EN

Hydrical reclamation of the residual pit of Most-Ležaky is part of the comprehensive revitalisation of the land affected in the past by mining activity with an area of 1264 ha. .us, in terms of remediation and reclamation, the most appropriate way to reclaim the residual pit, as one of the final stages of the long-term reclamation activities that have been going on in the area for more than half a century, occurs under the given conditions. .e Lake Most, our study area, was planned and created as a hydric recultivation of the former surface Most-Ležaky mine located near the town of Most, in the foothills of the Ore Mountains, approximately 80 kilometers northwest of the capital of the Czech Republic - Prague. .e Lake Most represents extensive hydric reclamation, which is unique in the sense that it does not have a natural inflow and runoff, therefore an artificial feeder from the Ohře River had to be built. .e main goal of the ongoing research is to construct a mathematical model predicting the water balance of Lake Most. .erefore, it is important to separate amount of water that is lost by the evaporation and amount of water that is lost into the subsoil. If we do not wish to use only temperature equations but more complex methods and equations to calculate evaporation instead, we need to have relative humidity, atmospheric pressure, wind speed, and daylight length values. In addition to the climatic data needed to calculate the evaporation, the amount of precipitation is needed to construct the balance equation of the area. An important objective in planning all hydric reclamations is to ensure their long-term sustainability, which is based on a detailed description of the study area's climate and local hydrological conditions. In our article we focus on assessing the evolution of climate in the area of this hydric reclamation. We have processed a long-term series of measurements in monthly averages from the Kopisty meteostation data provided by the Institute of Atmospheric Physics of the CAS.

PL

Jezioro Most jest wyjątkowe w tym sensie, że nie ma naturalnego dopływu i odpływu, dlatego konieczne było wybudowanie sztucznego dopływu rzeki Ohře. Głównym celem prowadzonych badań jest zbudowanie modelu matematycznego prognozującego bilans wodny jeziora Most. Dlatego ważne jest, aby zbilansować ilość wody traconej w wyniku parowania od ilości wody traconej do podłoża. Poza zależnościami od temperatury, wykorzystano bardziej złożone metody i równania do obliczenia efektu parowania, uwzględniające wartości wilgotności względnej, ciśnienia atmosferycznego, prędkości wiatru i długości dnia. Oprócz danych klimatycznych potrzebnych do obliczenia parowania, w rownaniach bilansu uwzględniono ilość opadów. Ważnym celem przy planowaniu rekultywacji wodnej jest zapewnienie długoterminowej trwałości, co opiera się na szczegółowym opisie klimatu i lokalnych warunków hydrologicznych badanego obszaru. W naszym artykule skupiono się na ocenie ewolucji klimatu w badanym obszarze rekultywacji wodnej. Przetworzono serię długoterminowych pomiarów w średnich miesięcznych z danych meteorologicznych Kopisty dostarczonych przez Instytut Fizyki Atmosfery CAS.

13

El-Nino effect on reservoir capacity reliability: Case study of Sumi dam, Sumbawa Island, Indonesia

Andawayanti Ussy, Yasa I. Wayan, Bisri Mohammad, Sholichin Mochamad, Sulianto

Journal of Water and Land Development

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2020

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no. 44

1--7

EN

Reservoirs have a very important function in providing multi-sector water requirements. In the future, reservoirs not only serve to store and available water can also be used as disaster mitigation instruments. The completeness of hydrological measurements in reservoirs can be expanded more widely for climate change mitigation. The reliability of the reservoir capacity varies greatly depending on the El-Nino character that occurs among them El-Nino is weak, moderate, strong and very strong. The El-Nino characteristic is very influential on the period of water availability, the increase of evaporation capacity and decrease of reservoir capacity. Analysis of the reliability of the reservoir volume due to El-Nino using the Weibull equation. The deficit reservoir was calculated using the concept of water balance in the reservoir that is the relationship between inflow, outflow, and change of storage at the same time. Based on the results of the analysis showed that the evaporation increase and the decrease of reservoir capacity had a different pattern that is when the evaporation capacity started to increase at the same time the reservoir capacity decreased significantly. The correlation coefficient between evaporation capacity increase and decrease of reservoir water capacity are consecutively –0.828, –0.636, and –0.777 for El- Nino weak, moderate and very strong respectively. At the reservoir capacity reliability of 50% reservoir has a significant deficit. When weak El-Nino the deficit is 2.30∙106 m3, moderate: 6.58∙106 m3, and very strong 8.85∙106 m3.

14

Mechanical Properties of HTPE/Bu-NENA Binder and the Kinetics of Bu-NENA Evaporation

Yuan Shen, Luo Yunjun

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 1

119--141

EN

The correlation between the mechanical properties of hydroxyl-terminated polyether (HTPE)/N-butyl-N-(2-nitroxyethyl)nitramine (Bu-NENA) binders with different plasticization ratios (pl/po), varied from 0.9 to 1.5, have been studied. The very early stage of evaporation of Bu-NENA from the HTPE/Bu-NENA binder, with a pl/po ratio of 1.2, has been investigated. The results revealed that the pl/po ratio has strong influences on the mechanical properties. When the pl/po ratio was 1.2, the mechanical properties of the HTPE/Bu-NENA binder were satisfactory, the maximum tensile strength and the elongation at break being 2.39 MPa and 93.27%, respectively. The evaporation rate constant of Bu-NENA from HTPE/Bu-NENA binder with a pl/po ratio of 1.2 increased from 0.31·10–5 to 2.32·10–5 s–1 as the temperature was increased from 50 to 90 °C. The value of the activation energy of evaporation was 51.47 kJ/mol and its pre-exponential factor was 6.14·102 s–1.

15

Water Economy Balance of the Almaty City

Chigrinets Alexander G., Mazur Lidiya P., Duskayev Kassym K., Chigrinets Larissa Y., Akhmetova Saniya T.

Journal of Ecological Engineering

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2019

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Vol. 20, nr 3

194--203

EN

This article provides and analyses the detailed water balances of the Almaty city in regards to the water resources, the share of which for different water bodies is 50%, 75% or 95% at the present level of surface and groundwater use. We have quantitatively assessed such surface water resources for specific water bodies and for the whole city. We have analysed the field studies of channel water balances of small rivers conducted in 2006, 2007 and 2013 (Almaty city) to identify the areas of abstraction losses and groundwater outcrop in riverbeds. The water balance analysis shows that Almaty city suffers from significant deficits in water resources. On the basis of the population growth dynamics, we assume that it will only increase. We have clarified the methods for calculating hydrometeorological characteristics and gained the updated information about the stream flows in a number of control sections and the channel water balances of the Karasu.

16

Evapotranspiration of Technical Substrates – Methodology for Calculating Evapotranspiration of Technical Substrates

Weiss Oliver, Scharf Bernhard, Pitha Ulrike

Journal of Ecological Engineering

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2019

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Vol. 20, nr 9

28--37

EN

The existing formulae, like the well-known Penman-Monteith equation, used for calculating evapotranspiration are characterized by great differences concerning their results. These differences stem from the diversified climatic conditions and vegetation specifics during their development. Every formula of evapotranspiration only delivers 100% correct results, if it is used under the same climatic condition it was developed in. Therefore, a new method for calculating evapotranspiration via specific, but comparatively easily established formula was presented. After a theoretical introduction for illustrating some fundamental aspects for this work, the test setup and approach for creating these formulae are described in detail. The test set up considers typical climatic conditions and simulates, for example, the average temperature of Vienna, a summer day and an extremely hot day. While using a polynomial correlation, a formula for calculating evapotranspiration at any temperature is possible. For determining the evapotranspiration rate (in mm/m2 per 24 hours day) due to the presented formula, only temperature, sort of vegetation and technical soil has to be defined. As a result, the relevance of this work is the presentation of a method to determine the evapotranspiration of any technical substrates (used for e.g. green roofs, façade greenery, indoor greenery, raingardens…) with or without any kind of vegetation, while using the created formula.

17

The Improvement of the Lake Most Evaporation Estimates

Dlouha Dagmar, Dubovsky Viktor

Inżynieria Mineralna

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2019

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R. 21, nr 1/2

159--164

EN

The Lake Most represents extensive hydric reclamation of the former surface mine of Most–Ležáky, which is unique in the sense that it does not have a natural inflow and runoff. The main goal of the ongoing research is to costruct a mathematical model predicting the water balance of Lake Most. Therefore, it is important to separate amount of water that is lost by the evaporation and amount of water that is lost into the subsoil. In this article, we focus on the possibilities of evaporation estimates and their improvements.

PL

Jezioro Most stanowi rozległy teren rekultywacji wodnej byłej kopalni odkrywkowej Most – Ležáky. Jezioro jest wyjątkowe w tym sensie, że nie ma naturalnego dopływu i odpływu. Głównym celem trwających badań jest opracowanie modelu matematycznego przewidującego bilans wodny jeziora Most. Dlatego ważne jest oddzielenie ilości wody utraconej w wyniku parowania i ilości wody utraconej w podłożu. W artykule skupiono się na możliwościach oszacowania parowania i ich ulepszeniach.

18

Zyski wilgoci z parowania jako parametr projektowy instalacji wentylacji krytych basenów pływackich

Przybylak Jagoda, Ratajczak Katarzyna

Instal

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2019

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nr 11

31--37

PL

Zyski wilgoci z parowania są istotnym parametrem wpływającym na projekt instalacji wentylacji w krytych basenach pływackich. W literaturze dostępnych jest wiele wzorów do obliczania wielkości zysków wilgoci. Trudne może być wybranie wzoru właściwego. Przedstawione analizy mają na celu pokazać, jaki jest wpływ wyboru zależności do wyliczania zysków wilgoci na wielkość przewodów wentylacyjnych, czyli na koszty inwestycyjne instalacji. Dokonano przeglądu wzorów do obliczania zysków wilgoci, wybrano trzy zależności rekomendowane w literaturze oraz wyznaczono strumień powietrza nawiewanego, wielkość przewodów wentylacyjnych oraz centrali wentylacyjnej. Wyniki pokazują, że poprzez wybranie różnych wzorów do wyznaczania zysków wilgoci koszty przewodów wentylacyjnych oraz central wentylacyjnych zastosowanych w przykładowym obiekcie basenowym mogą różnić się w skrajnych przypadkach nawet pięciokrotnie. Wykazano, że przyjęcie nawet średniej wartości zysków wilgoci daje wyniki zawyżone w stosunku do ilości odparowującej wody zmierzonej w obiektach rzeczywistych. Z uwagi na mnogość wzorów do wyznaczania zysków wilgoci w basenach krytych należy uważnie wybierać wzór do zastosowania, ponieważ zyski wilgoci są bardzo istotnym parametrem projektowym, który wpływa na koszty inwestycyjne oraz eksploatacyjne.

EN

Moisture gains from evaporation are an important parameter affecting the design of a ventilation system in indoor swimming pools. There are many formulas available in the literature for calculating the amount of moisture gain. It may be difficult to choose the right one. The analyzes presented are intended to show what is the impact of the choice of formula to calculate moisture gains on the size of ventilation ducts, i.e. the investment costs of the installation. The formulas for calculating the moisture gains were reviewed, three recommended in the literature were selected and the supply air stream was determined as well as the size of ventilation ducts and the ventilation unit. The results show that by choosing different formulas for determining moisture gains, the costs of ventilation ducts and air handling units used in an example pool facility may vary in extreme cases even up to five times. It has been shown that the adoption of the average value of moisture gains results in excessive results in relation to the amount of evaporating water measured in real facility. Due to the multiplicity of formulas for determining moisture gains in indoor pools, the applied formula needs to be carefully chosen, because moisture gains are a very important design parameter that affects investment and operating costs.

19

Numerical study of flow maldistribution in plate heat exchangers used for evaporation process

Pluszka Paweł, Brenk Arkadiusz Patryk, Malecha Ziemowit Miłosz

Archives of Thermodynamics

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2019

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Vol. 40, no 3

57--82

EN

Geometry of plate heat exchangers (PHE) is characterized by a complex net of narrow channels. It enhances turbulence and results in better heat transfer performance. Theoretically, larger number of channels (plates) should proportionally increase the PHE heat power capacity. In practice a nonuniform massflow distribution in consecutive flow channels can significantly deteriorate the overall heat exchange performance. The flow maldistribution is one of the most commonly reported exploitation problems and is present in PHE with and without phase-change flows. The presented paper investigates numerically a flow pattern in PHE with evaporation of R410A refrigerant. Various sizes of PHE are considered. The paper introduces a robust methodology to transform the complicated geometry of a real 3D PHE to its 2D representation. It results in orders of magnitude faster calculations and allows for fast evaluation of different geometrical changes of PHE and their effect on flow maldistribution.

20

Non-alcoholic beer production – an overview

Jackowski M., Trusek A.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 4

32--38

EN

Through years beer became one of the best known alcoholic beverages in the world. For some reason e.g. healthy lifestyle, medical reasons, driver’s duties, etc. there is a need for soft drink with similar organoleptic properties as standard beer. There are two major approaches to obtain such product. First is to interfere with biological aspects of beer production technology like changes in mashing regime or to perform fermentation in conditions that promote lower alcohol production or using special (often genetic modified) microorganism. Second approach is to remove alcohol from standard beer. It is mainly possible due to evaporation techniques and membrane ones. All these approaches are presented in the paper.