Wyniki wyszukiwania - BazTech

1

Impact of temperature, bed height, and particle size on Ni(II) removal in a continuous system: Modelling the break curve

Villabona-Ortíz Ángel, Tejada-Tovar Candelaria, Ortega-Toro Rodrigo, Peña-Romero Keily, Botello-Urbiñez Ciro

Journal of Water and Land Development

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2022

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no. 52

257--264

EN

The objective of this research was to evaluate the adsorption capacity of the shell biomass (Dioscorea rotundata), taking into account the impact of temperature, bed height, and particle size on the removal of nickel(II) ions in aqueous solution in a continuous fixed-bed column system; performing the modelling of the break curve. The biomass was characterised by SEM-EDS analysis. The analysis found that it represents a rough, heterogeneous structure, rich in carbon and oxygen, with mesopores, and is suitable for removing heavy metals. It also determined the optimum parameters of the bed height, particle size, and temperature, keeping the pH and the initial concentration of the solution constant. The results revealed that the bed height and the particle size are the two most influential variables in the process. Ni(II) removal efficiencies range between 85.8 and 98.43%. It was found that the optimal conditions to maximise the efficiency of the process are temperature of 70°C, 1.22 mm particle size, and 124 mm bed height. The break curve was evaluated by fitting the experimental data to the Thomas, Adams-Bohart, Dose-Response, and Yoon-Nelson models, with the Dose-Response model showing the best affinity with a coefficient of determination R2 of 0.9996. The results obtained in this research showed that yam shell could be suggested as an alternative for use in the removal of Ni(II) ions present in an aqueous solution in a continuous system.

2

Experimental studies of packed-bed Thermal Energy Storage system performance

Ochmann Jakub, Bartela Łukasz, Rusin Krzysztof, Jurczyk Michał, Stanek Bartosz, Rulik Sebastian, Waniczek Sebastian

Journal of Power Technologies

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2022

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Vol. 102, nr 1

37--44

EN

This paper contains an experimental analysis of a heat storage tank's heat loss and exergy efficiency using a basalt porous bed as a storage material. The basic parameters of the laboratory bench with measuring equipment are presented and the experimental procedure is discussed. The methodology for evaluating the energy potential of the heat storage process for large-scale energy storage systems is described. The main novelty of the presented system is the application of the slenderness of the heat accumulator, which corresponds to the development of the system in a post-mining shaft. Based on the analysis of the experiment, the exergy cycle efficiency of the heat storage unit was determined to equal 52.3%, and the energy efficiency equal to 96.6%.

3

Role of thermal energy storage technology in the decarbonization of energy sector process - packed rock bed parameters analysis

Ochmann Jakub, Jurczyk Michał, Bartela Łukasz

Architecture Civil Engineering Environment

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2022

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Vol. 15, no. 3

65--74

EN

The paper presents the adiabatic installation of compressed gases energy storage. The authors present the results of analyzes for this type of installation due to the selection of thermal storage material. The simulations were carried out for basalt, granite and ceramics (alumina) as well as for porosity value from 0.375 to 0.39 of basalt-filled reservoirs in Thermal Energy Storage (TES) installation. Characteristics of outlet air temperature, air pressure drop amount of energy stored and external heat losses as a time functions during the charging phase are presented. The research indicated that due to the lowest density and average heat capacity of the materials studied, granite has the fastest and most intense physical exit loss from the storage tank which was approximately 1100 W. However, there was no significant effect on air pressure drop depending on the chosen accumulation materials. The effect of rock bed porosity on the pressure drop of flowing air was investigated. For a constant mass flow rate, pressure drop values ranging from 2200 Pa to 6200 Pa were obtained depending on the porosity value.

4

Badania modelowe przepływu żużli w wielkim piecu

Panic Bogdan

Hutnik, Wiadomości Hutnicze

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2021

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Vol. 88, nr 5-6

2--5

PL

Przeprowadzono badania eksperymentalne przepływu przez złoże kawałkowe cieczy o różnych lepkościach. Dla realizacji badań zaprojektowano i skonstruowano instalację badawczą w układzie 2D. Wyznaczono prędkości przepływu cieczy modelowych przez złoże kawałkowe. Zbadano zachowanie dwóch cieczy o różnych lepkościach, spływających w złożu kawałkowym. Podczas badań uwzględniono liczby Reynoldsa, Galileusza oraz liczbę kapilarną, wskazujące na podobieństwo warunków prowadzonych badań do warunków panujących w wielkim piecu.

EN

Experimental studies of the flow of liquids with different viscosities through a packed bed were carried out. In order to carry out the research, a 2D research installation was designed and constructed. The flow velocities of model liquids through the packed bed were determined. The behavior of two liquids of different viscosities flowing in a packed bed was investigated. Reynolds, Froude and capillary criteria indicated the similarity of study conditions with blast furnace condition.

5

Applying CFD for studying the dynamic and thermal behavior of an indirect solar dryer: paramertric analysis

Khaldi S., Korti A. N., Abboudi S.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 1

253--272

EN

In this work, an indirect solar dryer integrated thermal storage for drying figs. (Ficuscarica) is studied numerically. Unsteady turbulent airflow and heat transfer through a two-dimensional model is carried out for a typical day of August under the climatic conditions of Tlemcen (Algeria). Effects of air inlet size and thickness of the packed bed on the dynamic and thermal behaviors of the dryer with and without packed bed have been discussed. The study shows that: (1) Increase the inlet size from 0.04 m to 0.10 m can accelerate the extraction of air by about 13% and reduce the maximum crops temperature by about 14%. (2) The packed bed can reduce the mass flow rate extracted by 22% and the fluctuations of air temperature by 1.3%. (3) A packed bed with a thickness of 0.15 m can extend the operating time of the dryer up to 23%.

6

Homogenizacja emulsji o/w podczas przepływu przez złoże mikrocząstek węglika krzemu

Różański J., Kuczora A.

Inżynieria i Aparatura Chemiczna

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2018

|

Nr 4

116--117

PL

Przedstawiono wyniki badań przepływu rozcieńczonych emulsji olej-woda przez złoże mikrocząstek węglika krzemu (71÷100 µm). Olej mineralny był fazą rozproszoną (5 i 15% obj.), a Tween 40 wykorzystano jako emulgator. Przetłoczone przez złoże emulsje zawierały mniejsze krople oleju i były bardziej jednorodne od emulsji wstępnej. Użyte złoże przede wszystkim spowodowało zanik kropel o średnicy większej od 30 µm. Zaobserwowano również silny wpływ stężenia emulsji na spadek ciśnienia.

EN

The results of study on the flow of diluted o/w emulsions through packed beds of Silicon carbide microparticles (71÷100 µm) are reported. The mineral oil as dispersed phase (5 vol% and 15 vol%) and Tween 40 as emulsifier were used. The emulsions pressed through the packed bed contained smaller oil droplets and were more uniform than the preliminary emulsion. The packed bed used in the study caused mainly the disappearance of droplets with diameters greater than 30 µm. A strong effect of emulsion concentration on pressure drop was also observed.

7

Biomass drying: Experimental and numerical investigations

Żabski J., Lampart P., Gumkowski S.

Archives of Thermodynamics

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2018

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Vol. 39, no 1

39--73

EN

Results of experimental and numerical investigations of wood chips drying are described in the paper. Experiments are carried out on two test facilities: a small laboratory rig and a larger pre-prototype dryer. Both facilities are thorough-circulation convective air dryers. The first one is a batch dryer, whereas the second one is a continuous dryer with wood chips flowing down by gravity from a charging hopper to a gutter with the aid of screw-conveyor. The latter is considered a half scale model (preprototype) for professional drying installations. A low feeding rate of wood chips into the pre-prototype dryer makes the process quasi-stationary and the difference between it and a batch drying is negligible. So, most experiments at this facility were carried out as batch dryers with non-agitated packed beds. The investigations exhibit the same linear correlation between the mass of evaporated water from the packed bed and the drying air velocity for both facilities. Numerical analysis of the drying process is conducted using the Ansys Fluent software enriched in drying capabilities by means of self-written procedures – user defined functions. Simulations confirmed a phenomenon of a drying front observed in the small laboratory rig. A thin layer of wood chips comprises the whole heat exchange and moisture evaporation phenomenon. The drying front travels downstream in the course of the process separating the already dried layer and still wet layer.

8

Zagadnienia pomiaru wymiany ciepła w złożu warzyw i owoców

Łapiński A., Kołodziejczyk M., Butrymowicz D.

Chłodnictwo : organ Naczelnej Organizacji Technicznej

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2017

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R. 52, nr 3

12--18

PL

Artykuł przedstawia przegląd literatury w zakresie wymiany ciepła w upakowanym złożu warzyw. Przedstawione i opisane zostały różne podejścia w zakresie technik pomiaru oraz wyniki badań eksperymentalnych w postaci bezwymiarowych zależności korelacyjnych opisujących wymianę ciepła. W przeglądzie przeanalizowano metody pomiarowe odnoszące się głównie do wymiany ciepła w upakowanych złożach wykonanych ze sztucznych elementów o stałych regularnych kształtach tj. płaskich płyt, kuł lub cylindrów.

EN

The paper presents state of the art in problems of heat transfer in packed bed consisted of vegetables and/or fruits. Various approaches were presented along with possible formulations of the dimensionless relationships describing heat transfer. The presented review deals with packed bed consisted of the elements of the regular shapes, e.g. flat plates, balls, and cylinders.

9

Pomiar współczynnika wnikania ciepła w złożu warzyw przy zastosowaniu metody przedmuchowej

Łapiński A., Butrymowicz D.

Chłodnictwo : organ Naczelnej Organizacji Technicznej

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2017

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R. 52, nr 4-5

20--26

PL

W artykule przedstawiono wykorzystanie metody przedmuchowej do pomiaru współczynnika wnikania ciepła w upakowanym złożu warzyw. Została przedstawiona i opisana metoda przedmuchowa (ang. single blow technique), a także przystosowanie jej do pomiarów z elementami złoża o skomplikowanej geometrii. Dodatkowo przedstawiono stanowisko pomiarowe skonstruowane do metody przedmuchowej wraz z wynikami pomiarów, jakie uzyskano przy badaniu złoża marchwi.

EN

The paper presents the application of the single blow technique to mea-sure of heat transfer coefficient in packed bed of vegetables. The methodology of the measurement approach was presented along with its adjustment for the measurements with bed elements of complex geometry. The testing rig was also presented. The experimental results obtained for the packed bed composed of carrots were presented.

10

External Mass Transfer Model for Hydrogen Peroxide Decomposition by Terminox Ultra Catalase in a Packed-Bed Reactor

Grubecki I.

Chemical and Process Engineering

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2017

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Vol. 38, nr 2

307--319

EN

It is known that external diffusional resistances are significant in immobilized enzyme packed-bed reactors, especially at large scales. Thus, the external mass transfer effects were analyzed for hydrogen peroxide decomposition by immobilized Terminox Ultra catalase in a packed-bed bioreactor. For this purpose the apparent reaction rate constants, kP, were determined by conducting experimental works at different superficial velocities, U, and temperatures. To develop an external mass transfer model the correlation between the Colburn factor, JD, and the Reynolds number, Re, of the type JD = K Re(n-1) was assessed and related to the mass transfer coefficient, kmL. The values of K and n were calculated from the dependence (am kp-1 - kR-1) vs. Re-1 making use of the intrinsic reaction rate constants, kR, determined before. Based on statistical analysis it was found that the mass transfer correlation JD = 0.972 Re-0.368 predicts experimental data accurately. The proposed model would be useful for the design and optimization of industrial-scale reactors

11

Measurement approach of mean heat transfer coefficient for packed bed of vegetables

Łapiński A., Butrymowicz D., Kołodziejczyk M.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 1

73--80

EN

The non-invasive measurement approach of the mean heat transfer coefficient for the packed bed of vegetables may be thought as still open issue. There is a clear need for the assessment of heat transfer conditions for various types of fruits and vegetables in order to accurately predict the thermal load that is necessary to select refrigeration equipment for cold storage chamber. Additionally, there is significant development in numerical modelling of heat and mass transfer processes in cold storage chambers for fruits and vegetables which requires precise heat transfer prediction. The theoretical basis for the indirect measurement approach of mean heat transfer coefficient for the packed bed of vegetables that is based on single blow technique is presented and discussed in the paper. The approach based on the modified model of Liang and Yang was presented and discussed. The testing stand consisted of a dedicated experimental tunnel along with auxiliary equipment and measurement system are presented. The geometry of the tested vegetables bed were presented. Selected experimental results of heat transfer are presented and discussed for the packed bed of carrots. These results were presented as dimensionless relationship. The obtained results were compared with the existing dimensionless relationships developed for the packed bed consisting of elements of various regular shapes.

12

Modelling of the hydrodynamics of concurrent gas and liquid flow through packed bed

Janecki D., Bartelmus G., Burghardt A.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2016

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nr 19(3)

267--284

EN

The aim of the present study is to simulate concurrent gas and liquid flow through packed bed in the gas continuous flow regime (GCF) and continuity shock waves regime(CSW) using computational fluid dynamics (CFD). The application of multiple gas-liquid-solid model requires the knowledge of relationships determining interactions between phases. The exchange coefficients of these forces were defined by means of equations suggested by ATTOU et al. (1999). As a result of the computational simulation the following data were obtained: gas pressure drop in the bed, volume fraction distribution of a given phase (liquid and gas holdups) along the packing and its mean value in the reactor. The comparison of the values of the hydrodynamic parameters, both calculated and obtained experimentally in a column packed with 3 mm glass spheres, indicates that CFD model can be applied to model the hydrodynamics of concurrent gas and liquid flows through a packed bed because a good compatibility of the compared parameters was obtained.

13

Agregacja cząstek drewna w procesie biofiltracji pod wpływem wilgoci

Grubecki I.

Inżynieria i Aparatura Chemiczna

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2016

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Nr 3

93--94

PL

Przeprowadzono badania mające na celu określenie wpływu zawartości wilgotności na opory przepływu powietrza przez złoże biofiltracyjne złożone z nieregularnych zrębków drewna. Przeanalizowano dziewięć poziomów zawartości wilgoci w złożu. Na tej podstawie określono wpływ zawartości wilgotności złoża na jego powierzchnię właściwą. Wykazano, że wzrost zawartości wilgoci w złożu powoduje agregację cząstek drewna, a w konsekwencji drastyczny spadek powierzchni właściwej doża i wzrost średnicy Sautera.

EN

Experiments were carried out to determine the influence of moisture content in a packed bed made of irregular wood chips on the pressure drop of air flowing through this bed. The nine moisture content levels were analyzed. As a result, the influence of moisture content in a packed bed on its specific surface area was established. It was found that the increase of moisture content caused the aggregation of wood particles and, as consequence, the drastic reduction of specific surface area and the increase of Sauter diameter.

14

Anisotropy of effective thermal conductivity analysis of heat transfer coefficient distribution around spherical particles in a packed bed

Asakuma Y., Asada M., Kanazawa Y., Yamamoto T.

Computer Assisted Methods in Engineering and Science

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2015

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Vol. 22, no. 1

31--38

EN

Effective thermal conductivity with radiation is analyzed by a homogenization method. The method used can precisely represent the conditions around particles in a packed bed. In this study, the effects of variation in parameters such as heat transfer coefficient distribution around spherical particles in a packed bed, Reynolds number, temperature and particle size on the conductivity were estimated in order to elucidate the heat transfer mechanism of complex packed structures. The results show that it is unnecessary in heat transfer analysis to consider the anisotropic behavior of the flow direction for larger particles, high Reynolds numbers and high temperatures. However, the heat transfer was anisotropic for smaller particle sizes.

15

Wpływ zawartości wilgoci na powierzchnię właściwą złoża biofiltracyjnego złożonego z nieregularnych cząstek drewna

Grubecki I., Trawczyńska I.

Inżynieria i Aparatura Chemiczna

|

2014

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Nr 4

243--244

PL

Zbadano wpływ wilgotności na opory przepływu powietrza przez złoże biofiltracyjne złożone z nieregularnych zrębków drewna. Przeanalizowano siedem poziomów wilgotności złoża. Na tej podstawie określono wpływ zawartości wilgoci złoża na jego powierzchnię właściwą. Wykazano, że istnieje wilgotność złoża, po przekroczeniu której następuje gwałtowny spadek jego powierzchni właściwej.

EN

The influence of moisture content in a packed bed made of irregular wood chips on the resistance of air flowing through this bed was examined. Seven moisture content levels were analyzed. As a result the influence of moisture content in a packed bed on its specific surface area was determined. It was found that there was a certain moisture content value above which a drastic change in specific surface area occurred.

16

Modeling of heat and mass transfer in LaNi5 matrix during hydrogen absorption-desorption cycle

Akanji O. L., Kolesnikov A. V.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 3

71-76

EN

Packed bed reactors using metal hydride are attracting a lot of attention as potential hydrogen storage systems. Some operational and design variables are major constraints to obtain a proper infl ow/outfl ow of hydrogen into a metal hydride reactor. These variables include packed bed thermal conductivity, porosity, pressure and temperature distributions in the reactor during the absorption/desorption cycle. They also cause a mechanical stress induced by temperature gradient. In this paper, two dimensional models are implemented in COMSOL multiphysics to simulate the hydrogen fl ow, pressure and temperature distributions in the packed bed reactor during absorption/desorption cycle. Also, stresses in porous metal hydride induced by temperature variation in the heating/cooling cycle were evaluated. A possible effect of stress induced, porosity changes on diffusion and heating of hydrogen in both radial and axial direction in packed bed is discussed. The model consists of a system of partial differential equations (PDE) describing structural mechanics of stress, heat and mass transfer of hydrogen in the porous matrix of the packed bed reactor.

17

Modelowanie przeciwprądowego przepływu gaz - ciecz w złożu porowatym

Niegodajew P., Asendrych D.

Modelowanie Inżynierskie

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2012

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T. 14, nr 45

108--115

PL

Praca dotyczy modelowania przeciwprądowego przepływu dwufazowego gaz-ciecz w kolumnie z wypełnieniem porowatym. Wielofazowy model eulerowski został wykorzystany do opisania ruchu płynu w dwu-wymiarowej, osiowosymetrycznej domenie obliczeniowej. Jako czynniki zastosowane zostały woda i powietrze. Opory przepływu fazy dominującej, tj. gazu, zostały wyznaczone na drodze eksperymentalnej. Uzyskane wyniki obliczeń wskazują na adekwatność zastosowanego modelu do analizowanego przepływu.

EN

The paper deals with the numerical modelling of countercurrent flow through the absorber column with packed bed inside. Model geometry follows the real pilot plant absorber column localized in IChPW in Zabrze. The Euler-Euler model was applied to treat the gas-liquid system in 2-dimensional and axisymmetric domain. The flow is dominated by the gas phase and the liquid creates the film on the packed bed. The results obtained have shown the realistic behaviour of the system in terms of its hydrodynamics.

18

Comparison of kinetics of black shale bioleaching process using stationary and agitated systems

Sadowski Z., Szubert A.

Physicochemical Problems of Mineral Processing

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2007

|

Vol. 41

387-395

EN

In the study, the kinetics of black shale ore bioleaching process, carried out in small column and tank reactor, was investigated. During all experiments the concentration of Cu2+ ions in the leaching solution was determined as a function of leaching time. Based on the results obtained, kinetics of bioleaching processes in the agitated tank reactor and column reactor were compared. The rate of bioleaching in column was similar to that in agitated tank. For the experiments in column, two different types of packing materials (plastic bullets and sawdust) were tested in order to improve the bed porosity. The results showed that sawdust was the best packing material used in this study.

PL

W pracy przedstawiono wyniki doświadczeń przeprowadzonych na dwóch próbkach rudy łupkowej o zawartości miedzi 7,04 % (próbka A) i 2,32 % (próbka B). Obie próby materiału do badań zostały dostarczone przez Centrum Badawczo-Rozwojowe KGHM Cuprum. Przeprowadzone doświadczenia miały za cel porównanie procesu bioługowania próbek rudy łupkowej, który był prowadzony z bioreaktorze z mieszaniem i w kolumnie ze złożem stacjonarnym. W przypadku bioługowania w kolumnie użyto dodatkowo dwóch wypełniaczy, to jest plastikowych kulek i wiórów drewnianych. Bioługowanie prowadzono z wykorzystaniem bakterii heterotrofowych (Streptomyces setoni i mieszanka C) i autotrofowych (Acidithiobacillus ferrooxidans). Otrzymane wyniki sugerują, że kinetyka procesu bioługowania w bioreaktorze był lepsza od kinetyki procesu w kolumnie. Procesy, prowadzone w kolumnach z wypełnieniem, były korzystniejsze w porównaniu z procesami bez użycia wypełnienia. Z zastosowanych dwóch materiałów wypełniających, trociny okazały się być lepszym wypełniaczem. Może to być spowodowane bardziej porowatą strukturą materiału w kolumnie, o czym świadczy większa szybkość przepływu medium ługującego.

19

The effect of boundary conditions on effective thermal conductivity of heterogeneous materials in transient state

Polesek-Karczewska S.

Archives of Thermodynamics

|

2003

|

Vol. 24, no 4

3-14

EN

The measured temperature distributions in the layer of heated packed bed is presented in the paper. Analytical solutions of Fourier heat conduction equation for two different boundary conditions are found. The comparison of between the experimental data and theoretical predictions are used to estimate the corresponding values of effective thermal conductivity, which is the matching parameter of considered problem. The analysis leads to the conclusion that the contribution of radiation mechanism in the transient processes in non-homogeneous materials may be considerable for the jump boundary conditions.

20

Wpływ zraszania na stopień absorpcji w kolumnie wypełnionej

Poliński P., Chacuk A.

Inżynieria Chemiczna i Procesowa

|

2001

|

T. 22, z. 3D

1169--1174

PL

W pracy określono wpływ niepełnego kontaktu fazy gazowej i ciekłej wywołanego złym zraszaniem wypełnienia. To złe zraszanie zostało ujęte w dwojaki sposób: część gazu nie ulega kontaktowi z cieczą wzdłuż całej kolumny (bocznikowanie gazu); część gazu nie kontaktuje się z cieczą jedynie na pewnej wysokości złoża, po przekroczeniu której następuje idealne wymieszanie gazu będącego i nie będącego w kontakcie z cieczą. Określenie wpływu niepełnego kontaktu faz zostało przeprowadzone na podstawie izotermiczno-izobarycznej absorpcji dwuskładnikowej roztworów rozcieńczonych w kolumnie wypełnionej pierścieniami Raschiga. Uzyskane wyniki obliczeń wskazują na znaczny wzrost stopnia absorpcji w kolumnie z bocznikowaniem gazu, po wprowadzeniu do niej podziału na warstwy.

EN

The influence of incomplete contact between gas and liquid phases in the packed column caused by incomplete sprinkling of the bed was described in the paper. The incomplete sprinkling was approached in two ways: part of gas was not in contact with the liquid along the entire column (gas shunting); part of gas was not in contact with the liquid only on certain height of the packing, above which there was a perfect mixing of gas. The influence of incomplete contact between the phases was determined on the basis of isothermal and isobaric binary absorption of dilute solutions in the packed column filled with Raschig rings. Results obtained indicate a substantial increase of absorption ratio in the column with gas shunting. The column was divided into layers.