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1

Biosorption of Hexavalent Chromium onto Ziziphus lotus Fruits Powder: Kinetics, Equilibrium, and Thermodynamics

El Yakoubi Nosair, El Ansari Zineb Nejjar, Ennami Mounia, El Kbiach Mohammed L’bachir, Bounab Loubna, El Bouzdoudi Brahim

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

321--332

EN

Ziziphus lotus has been the subject of several researchs because of its nutritional benefits and ecological attributes. The removal of hexavalent chromium Cr(VI) from a solution using powdered Zizphus lotus fruits, for its qualities of being inexpensive as well as environmentally friendly, was investigated. The results obtained showed that at pH = 2, at 30°C, after 600 min of adsorbent/adsorbate contact, with 100 mg/L as initial concentration of Cr(VI) and a biosorbent dosage of 5 g/L, the biosorption of Cr(VI) on Zizphus lotus fruit powder (ZLFP) is at its maximum rate. The sorption process was exothermic (∆H° = –6.69 kJ/mol), and was characterized by a positive entropy values (∆S° = 46.76 J/K mol) suggesting a high affinity of the ZLFP for Cr(VI). Given that the Gibbs free energy (∆G°) is negative and decreases as temperatures increase from 293 to 323 K, the process of biosorption is both feasible and spontaneous. The Temkin model and the Langmuir model both generated excellent fits to the equilibrium data. The maximum monolayer biosorption capacity was 36.11 mg/g. The pseudo second order model was used to fit the kinetic data relating to the adsorption of Cr(VI) on the ZLFP. The FTIR spectral analysis allowed the characterization of the biochemical groups mainly involved in the sorption of Cr(VI) ions on the ZLFP, and which are: N–C, H-O, O–C, H-C, and O=C. The capacity of Ziziphus lotus fruit as an inexpensive, effective, and ecofriendly biosorbent is confirmed through this study.

2

The relationships between the kinetic grinding parameters with interstitial fillings and the liberation degree of a chromite ore

Umucu Yakup, Deniz Vedat, Gursoy Hakan Y., Tokcan Isıl, Arsoy Zeyni

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 168254

EN

In this study, the relationships between the liberation degree and the kinetic breakage parameters of a chromite ore obtained from the Burdur (Türkiye) were examined under the laboratory conditions. Firstly, liberation degrees for chromite particles were determined by the particle counting method in a metal microscope for 4 different size groups. Secondly, the breakage parameter of chromite ore which was dry ground with a ball mill was obtained using standard test methods. Additionally, the model parameters were also determined for the fractional interstitial fillings (U) of the chromite sample. Thirdly, the kinetic grinding parameters were compared with the liberation degree of the chromite sample. As a result of the tests, a very good correlation was obtained with R2=0.998, and regression analysis in the grinding processing of the chromite ore was used to verify the validity of the relationship parameter of Si that was produced. To these, it was found that interstitial fillings (U=0.6, 0.8, 1.0, and 1.2) have an effect on the grinding.

3

Effect of Biological Pretreatment on Anaerobic Sewage Sludge Digestion: Using Growth Media for Methanogenic Bacteria and Kinetic Studies for Biogas Yield

Lihi Khadija, Auajjar Nabila, Hamdi Inass, Echchayeb Kaouatar, Attarassi Benaissa

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

178--186

EN

The valorization of sewage sludge, a by-product of wastewater treatment by anaerobic digestion (AD), is getting more attention as a result of the advantages it provides for the environment and economy. The current investigation is an experiment performed in a lab setting using a batch-operated anaerobic digestion reactor with a mesophilic temperature of 35°C. This study examined the generation of experimental biogas and biodegradability .The effect of pretreatment by methanogenic bacteria growth medium on anaerobic digestion of sewage sludge was studied on three different concentrations of growth media, a control, and a low, medium and high concentration of culture medium, with cumulative biogas production of 610N ml /gVS added, 750 N ml /gVS added, 900 N ml /gVS added, 10 N ml /gVS added, respectively, with biodegradability rate of 52.16%, 56.5%, 74.04%, 28.70% respectively. Biogas production was enhanced at a medium concentration of culture medium and inhibited at a high concentration during anaerobic digestion of sewage sludge. Additionally, a theoretical biogas estimate was evaluated using four kinetic models (Logistic function, Modified Gompertz, Transference function, and First order); which were utilized to match the experimental biogas generation process involving the anaerobic digestion of untreated and pretreated sewage sludge by various concentrations of growth media of methanogenic bacteria . The kinetic findings demonstrated that both models, Modified Gompertz and Logistic function, were useful for predicting biogas output and matched experimental biogas production.

4

Adsorption of Lead, Zinc, and Nickel Ions from Wastewater Using Coriander Seeds as an Adsorbent

Shamkhi Hibatallah Jamil, Hussein Tamara Kawther

Journal of Ecological Engineering

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2022

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Vol. 23, nr 1

158--168

EN

This research focused on using coriander seeds as low cost adsorbent to remove heavy metals ions such as lead, zinc, and nickel from wastewater. Different parameters were studied to obtain the best results, such as pH, contact time, adsorbent dosage, concentration of initial metals and agitation speed. The highest results were obtained at pH 6, 105 min contact time, 1 g/100 ml dosage, 50 mg/l initial concentration of metal ions and 200 rpm agitation speed at temperature 25 ± 2 °C, which were 95.926%, 89.799% and 79.255% for lead, zinc and nickel ions, respectively. The results were also categorized as the Langmuir and Freundlich models, and found that the Freundlich isotherm fit the experimental data better than the Langmuir isotherm. The pseudo-second order was shown to have a high degree of fitness based on kinetic data. The adsorbent was characterized using a variety of techniques, including Fourier transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FESEM).

5

Effect of Thermal Pretreatment on the Kinetic Parameters of Anaerobic Digestion from Recycled Pulp and Paper Sludge

Habchi Sanae, Lahboubi Nabila, Karouach Fadoua, Naim Ikram, Lahlou Yahya, Bakraoui Mohammed, Sallek Brahim, El Bari Hassan

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 1

192--201

EN

This paper investigates the influence of thermal pretreatment on kinetic parameters based on four kinetic models: Modified Gompertz, transference and logistic functions and first order equation. The kinetic modeling was applied on experimental results of previous study on producing methane from anaerobic digestion of Recycled Pulp and Paper Sludge (RPPS) under mesophilic conditions. We observed that the thermal pretreatment improve considerably improved the kinetic parameters mainly the methane production rate and the lag phase. Indeed, it can be noted that methane production rate μ increases significantly from a value of 4.72 to 16.27 ml/h using logistic function for 1 g VS/L added load. Then the lag phase parameter λ has dramatically decreased from 5.46 to 1.04 h using logistic function for 1.5 g VS/L added load. This means that the thermal pretreatment of RPPS accelerates the methane production process and saves time.

6

Improved understanding of Sodium hydroxide concentration role and kinetic model of cryolite reactive extraction in cathode Spent Pot Linings

Tropenauer Blaž, Klinar Dušan, Golob Janvit

Polish Journal of Chemical Technology

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2021

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Vol. 23, nr 1

37--44

EN

Spent Pot Lining (SPL) cathode pot, waste from the aluminium smelting process needs detoxification from cyanides, washing out water-soluble salts and extraction of the cryolite (Na3AlF6) decomposition products to be recycled. Revealed cryolite decomposition mechanism with NaOH opens possibilities to explore its critical role in the reactive extraction process. Common Na+ ion from NaOH hinders the solubility of the product but also drives mass transfer to the reaction site. Reaction mass balance provides adequate liquid to solid ratio (L/S) and NaOH concentration range. A newly developed kinetic model based on Whitman film theory and NaOH mass flow enables prediction of the reaction time to decompose cryolite to a low enough level. Results show that the internal particle resistance to transport (1/ks) is 19 times larger than the external (1/kl) one and governs the whole process.

7

Models using in metallurgical process management

Pustĕjovska Pavlina, Kardas Edyta, Toman Radek, Bařina Dominik, Jursova Simona

Zarządzanie Przedsiębiorstwem

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2020

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Vol. 23, nr 3

16--19

EN

The paper presents the possibilities of the application of different models for blast furnace operation management: thermodynamic and kinetic models and also coke degradation model. Thermodynamic and kinetic approaches in modelling metallurgical processes form are necessary basis for continuous analysis of the conditions under which the evaluated iron technology can actually work while achieving the highest productivity. They can be also useful for estimating of maximal rate of auxiliary fuels in specific conditions of the blast furnace iron making, what can help to optimize the cost of fuels. The aim of the article is to present the possibility of reducing the costs of pig iron production using models, especially the coke degradation model, which was used for Czech conditions. The model was developed in two options: a regressive non-linear statistical model, and a selflearning neuron network. Subsequently, both predictive model variants are compared.

8

Preparation and characterization of pH-sensitive hydrogels from photo-crosslinked poly(ethylene glycol) diacrylate incorporating titanium dioxide

Senol Sebnem, Akyol Emel

Materials Science Poland

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2020

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Vol. 38, No. 3

443--449

EN

The purpose of the present investigation was to prepare pH-sensitive hydrogels from photo-crosslinked poly(ethylene glycol) diacrylate (PEG-DA). Rutile titanium dioxide (TiO2) was employed to modify the PEG-DA hydrogels. The rutile titanium dioxide (TiO2) nanoparticles were prepared by direct oxidation of titanium in the presence of polyethylene glycol (PEG) at high temperature. The nanoparticles were characterized by FT-IR, XRD and SEM. The influence of experimental conditions, such as pH, type and amount of photoinitiators on the release profiles of donepezil hydrochloride (active pharmaceutical ingredient for Alzheimer disease) from modified PEG-DA hydrogels, was investigated. The drug release processes were analyzed kinetically using zero-order, first-order, Hixson-Crowell and Peppas models.

9

Seasonal variability of antibiotic resistance and biodiversity of tap water bacteria in Wrocław, Poland

Siedlecka Agata, Wolf-Baca Mirela, Piekarska Katarzyna

Environment Protection Engineering

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2020

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Vol. 46, nr 2

93--109

EN

Antibiotic resistance of bacteria has become a worldwide problem. Drinking water distribution systems (DWDSs) can be regarded as reservoirs of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). This study aims to provide a preliminary evaluation of seasonal changes in the occurrence of ARB and ARGs in Wrocław tap water samples. It also investigates the biodiversity of bacterial communities dwelling in Wrocław DWDS and compares them with worldwide literature reports. Third generation cephalosporins resistant bacteria were present in each season, with relative abundances reaching from 40.46% in spring to 99.86% in summer. β-lactams and tetracyclines resistant bacteria were present only in spring and autumn samples, with relative abundances reaching from 0.51% to 3.80%. Relative abundances of ARB fluctuated across the year, and no season-dependent trend was found. This suggests that other factors influenced the resistance phenomenon in Wrocław tap water. The investigated resistomes were represented only by several ARGs (qnrB, tetW, ermB,qacEΔ1). Class 1 integrons gene intI1 was also detected. Biodiversity of bacteria collected from large amounts of tap water was similar to that reported previously for Wrocław and worldwide DWDSs, with a prevalence of Proteobacteria, followed by Actinobacteria, Cyanobacteria, and Firmicutes.

10

Comparison of two single-solute models of potassium kinetics during hemodialysis

Pietribiasi Mauro, Waniewski Jacek, Zaluska Wojciech, Wójcik-Zaluska Alicia, Leypoldt John K.

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 3

938--949

EN

Optimal potassium removal in hemodialysis (HD) is an important but difficult to achieve goal, influenced by numerous factors. Two types of single-solute mathematical models have been previously proposed to assess potassium kinetics in HD: pseudo-one compartment ( p1) and two-compartment models (2c). We compared these two models in simulating potassium kinetics during HD sessions with different treatment settings. After estimation of unknown parameters via fitting to clinical data during 4 h sessions with a dialysate potassium of 2.6 ± 0.6 mmol/L, the models were used to simulate 4 HD sessions for each patient, resulting from the combination of session length (4 h vs. 8 h) and potassium dialysate concentration (2.6 vs. 0 mmol/L). The simulated potassium concentration profiles were similar under different treatment conditions, and predicted potassium removal during the treatments was 77 ± 24 mmol with the standard settings; both increases in session length and potassium dialysate to plasma concentration gradient resulted in a significant increase in potassium removed. Both models indicated similar minimum values of dialysate potassium concentration required to avoid post-HD hypokalemia: 1.18 ± 0.66 mmol/L for 4 h HD and 1.71 ± 0.52 mmol/L for 8 h HD. The models described similar kinetics for potassium during different combinations of treatment settings. Total removal of potassium and minimum dialysate concentration to avoid post-HD hypokalemia, were predicted without significant differences by both models. Although no model has a clear advantage in terms of describing clinical data, our analyses suggest that 2c might offer a better trade-off between physiological accuracy and over-parametrization.

11

A mathematical model of some viral-induced autoimmune diseases.

Kolev M., Nikolova I.

Mathematica Applicanda

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2018

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Vol. 46, no. 1

97--108

EN

We propose a new mathematical model of viral-induced autoimmune diseases. The model is described by a bilinear system of four integro-differential equations of Boltzmann type. We present numerical results illustrating several typical outcomes of autoimmune diseases. In particular, special attention is devoted to the role of the ability of effector immune cells to destroy target cells for the development of autoimmune diseases.

PL

W pracy został zaproponowany nowy matematyczny model chorób autoimmunologicznych wywołanych przez wirusy. Model opisany jest dwuliniowym układem czterech równań całkowo-różniczkowych typu Boltzmanna. Zaprezentowane są wyniki obliczeń numerycznych ilustrujące kilka typowych przebiegów takich chorób. Szczególną uwagę poświęca się roli zdolności efektorowych komórek odpornościowych do niszczenia komórek docelowych w rozwoju chorób autoimmunologicznych.

12

Modeling of Ozonation of C.I. Reactive Black 5 through a Kinetic Approach

Bilińska L., Żyłła R., Smółka K., Gmurek M., Ledakowicz S.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 5 (125)

54--60

EN

C.I. Reactive Black 5 (RB5) is the most commonly used dye in the textile industry. Ozone is a strong oxidan that can decompose many barely degradable pollutants, including dyes. Although there are many literature reports devoted to the treatment of textile wastewater and dye solutions by ozone, the ozonation mechanism and modeling of the kinetics is still not well covered. In this work a kinetic model of the process of RB5 decolourisation by ozone has been proposed and validated on the basis of experimental data. The experiments were carried out in a liquid-liquid system to avoid mass transfer limitation. A model was established for acid reaction medium. The main RB5 reaction was direct oxidation of the dye with molecular ozone. The self-decomposition of ozone in liquid phase was taken into account and described by an empirical equation. The reaction rate constants of RB5 with ozone were estimated from the experimental data in the range of (1.88 ± 0.08) × 104 – (2.53 ± 0.10) × 105 M-1s-1 (invariant with initial dye concentration). An empirical equation k′ 2 = 1.06 × 108(COH−)0.31 was built for the constant to make it dependent on the pH value. A solution of the non-linear inverse problem allowed for identification of the kinetic constants on the basis of the experimental data obtained. The model gave a good match between the prediction and experimental data for pH between 1.88 and 4.0.

PL

Reactive Black 5 (RB5) jest powszechnie stosowanym barwnikiem w przemyśle włókienniczym. Ozon, będący silnym utleniaczem, jest w stanie rozłożyć wiele trudno degradowalnych substancji w tym barwniki. Pomimo, iż oczyszczanie ścieków włókienniczych i roztworów barwników ozonem było tematem wielu pozycji literaturowych, niewiele pośród nich dotyczyło badań nad poznaniem mechanizmu utleniania oraz modelowania kinetyki tego procesu. W niniejszej pracy zaproponowano matematyczny model opisujący kinetykę procesu odbarwiania barwnika RB5 za pomocą ozonu. Walidacji dokonano poprzez porównanie wyników modelowania do danych eksperymentalnych. Eksperymenty prowadzono w układzie homogenicznym ciecz-ciecz, aby uniknąć limitacji transferu masy między fazami układu. Model został opracowany dla procesu przebiegającego w środowisku kwaśnym, gdzie główną reakcją było bezpośrednie utlenianie barwnika cząsteczkowym ozonem z jednoczesnym uwzględnieniem rozkładu ozonu w fazie ciekłej. Model opisano równaniem empirycznym. Wartości stałych szybkości reakcji RB5 z ozonem oszacowane na podstawie danych eksperymentalnych znajdowały się w zakresie od do M-1s-1 i były niezależne od początkowego stężenia substratu. W celu uzależnienia stałych szybkości od wartości pH, wyznaczono zależność empiryczną w postaci. Rozwiązanie nieliniowego problemu odwrotnego pozwoliło na identyfikację stałych kinetycznych na podstawie danych eksperymentalnych. Otrzymano dobrą zgodność pomiędzy wynikami modelowania a danymi doświadczalnymi dla wartości pH w zakresie 1,88-4,0.

13

Condensation polymerization of AB2 monomers – modeling and validation of model of polyreaction performed at the room temperature

Ryczek A., Lechowicz J. B., Walczak M., Galina H.

Polimery

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2016

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T. 61, nr 11-12

780--787

EN

Statistical and kinetic methods to model step polymerization of AB2 type of monomers (A and B stand for functional groups) are briefly reviewed and the relationships linking conversion or reaction time with averages of polymerization degree are derived for systems fulfilling the Flory-Stockmayer assumptions, i.e., for those with no reactivity changes of functional groups and absence of intramolecular linking. Results of kinetic studies are also presented for polymerization of 3,5-diaminobenzoic acid, aided with N,N'-diisopropylcarbodiimide, carried out at room temperature in NMR test tubes. For reaction carried out in dimethylsulphoxide, the relationship between conversion and time is well described by the simplest kinetic model. It was stated that in the case of reaction carried out in dimethylformamide the reactivity of the second amino group in the monomeric units seems to be ten times lower than that of the first one.

PL

Przedstawiono krótki przegląd statystycznych i kinetycznych metod modelowania stopniowej polimeryzacji monomerów typu AB2 (A i B reprezentują grupy funkcyjne). Wyprowadzono relacje łączące stopień przereagowania ze średnimi stopniami polimeryzacji dla układów reagujących zgodnie z założeniami Flory'ego i Stockmayera, tj. bez zmian w reaktywnościach grup funkcyjnych oraz nieobecności wiązań wewnątrzcząsteczkowych. Przedstawiono wyniki badań kinetycznych przebiegu polimeryzacji kwasu 3,5-diaminobenzoesowego wspomaganej N,N'-diizopropylokarbodiimidem, którą prowadzono w temperaturze pokojowej w probówkach NMR. Kinetykę badanej reakcji, prowadzonej w dimetylosulfotlenku, dobrze opisuje najprostszy model kinetyczny polikondensacji. Stwierdzono, że w przypadku reakcji prowadzonej w dimetyloformamidzie, reaktywność drugiej grupy aminowej w jednostkach monomerycznych jest dziesięciokrotnie mniejsza, niż reaktywność pierwszej z tych grup.

14

Toner recovery from suspensions with fiber and comparative analysis of two kinetic models

Trumic M. S., Antonijevic M. M.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

5--17

EN

This paper studies kinetic aspects of toner flotation in a mechanical cell with methyl isobutyl carbinol (MIBC) as a frother by using a synthetic toner sample 212+0 μm in a size at variable pH. The effect of the MIBC dosage and pH value on the flotation behavior of the toner has been investigated in terms of toner recovery and fiber recovery. Two kinetic models, the classical first order model and a modified first order model, have been tested and compared. It was established that the achieved optimal parameters of flotation were MIBC 1.5 mg/dm3 and pH from 7 to 12. The obtained results indicate that the toner floats rapidly and that flotation kinetics fits well the modified first order model with a very good correlation coefficient compared to the correlation coefficient for the classical first order model.

15

Using Mathematica software for coal gasification simulations – Selected kinetic model application

Iwaszenko S.

Journal of Sustainable Mining

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2015

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Vol. 14, iss. 1

21--29

EN

Coal gasification is recognized as a one of promising Clean Coal Technologies. As the process itself is complicated and technologically demanding, it is subject of many research. In the paper a problem of using volumetric, non-reactive core and Johnson model for coal gasification and underground coal gasification is considered. The usage of Mathematica software for models' equations solving and analysis is presented. Coal parameters were estimated for five Polish mines: Piast, Ziemowit, Janina, Szczygłowice and Bobrek. For each coal the models' parameters were determined. The determination of parameters was based on reactivity assessment for 50% char conversion. The calculations show relatively small differences between conversion predicted by volumetric and non reactive core model. More significant differences were observed for Johnson model, but they do not exceeded 10% for final char conversion. The conceptual model for underground coal gasification was presented.

16

The investigation of effect of wet-dry grinding condition and ball types on kinetic model parameters for kaolin

Umucu Y., Haner S., Tunay T.

Inżynieria Mineralna

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2015

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R. 16, nr 1

205--211

EN

Ceramics are products made from inorganic materials that are first shaped and subsequently hardened by heat. Many ceramic raw materials require crushing or disintegrating followed by dry or wet grinding to various degrees. Most of the energy is consumed in the grinding operations for the ceramic industry. As it is known, some of the energy during grinding is converted to heat that is fully not utilized in the grinding process. Thus, grinding is not a very efficient operation and it needs to be paid attention in detail. However, it is possible to set up a grinding system with a low energy consumption and higher efficiency of fineness before they can be used in ceramic manufacture. The type of grinding media exerts significant influence on milling performance in terms of product size and energy consumption. In recent years, various shapes of grinding media including rods, pebbles, and cylinders have been used as an alternative to balls. Cylinders have received particular attention because they have a greater surface area and higher bulk density than balls of similar mass and size. The objective of this study is to compare the wet and dry grinding of most frequently used ceramic raw materials namely, kaolin with the grinding of alumina ball type and cylbebs (pebbles).

PL

Produkty ceramiczne wykonane są z materiałów nieorganicznych, które najpierw się kształtuje, a następnie utwardza przy użyciu ciepła. Wiele surowych materiałów ceramicznych wymaga miażdżenia lub dezintegracji przy pomocy suchego lub mokrego mielenia w różnych stopniach. W przemyśle ceramicznym najwięcej energii zużywa się do reakcji mielenia. Jak wiadomo, część energii w trakcie mielenia zmienia się w ciepło, które nie jest w pełni wykorzystywane w procesie mielenia. Co oznacza, że mielenie nie jest zbyt opłacalną operacją i wymaga szczegółowej uwagi. Niemniej jednak, można ustawić system mielący z niższym wykorzystaniem energii i większą wydajnością rozdrabniania, zanim zostanie użyty w wytwórstwie ceramicznym. Rodzaj medium mielącego wywiera znaczący wpływ na proces mielenia w odniesieniu do rozmiaru produktu i konsumpcji energii. W ostatnich latach, jako alternatywę do kul wykorzystywano różnego kształtu medium mielącego, wliczając w to pręty, kamyki i cylindry. Największą uwagę zwrócono na cylindry, ponieważ posiadają większą powierzchnię właściwą i wyższą wielkość objętościową niż kule o podobnej masie i rozmiarze. Zamiarem badań jest porównanie mokrego i suchego mielenia najczęściej stosowanych materiałów ceramicznych, czyli kaolinu z mieleniem aluminiowymi kulami oraz przy użyciu cylbebu (kamyczków).

17

Wet Oxidation of Dairy Sewage: The Kinetic Study of Decomposition of the Milk Components

Piotrowska K., Imbierowicz M., Chacuk A.

Ecological Chemistry and Engineering. S

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2013

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Vol. 20, nr 3

531--541

EN

The article presents the results of kinetic studies of the wet oxidation process of dairy sewage. The dairy sewage, obtained straight from the production line, was subjected to oxidation at pH close to the natural value of 7. Experiments were carried out in a stirred batch tank reactor at the oxygen partial pressure equal to 1 MPa and at temperature ranging from 473 to 593 K. The effectiveness of organic compounds decomposition was estimated based on the measurement of TOC. The kinetics of decomposition of milk components, ie lactose, protein and fat, as well as the kinetics of oxidation of intermediate products was the aim of the study. Measurement of the concentration of protein, fat and lactose was done with a milk composition analyzer, calibrated in relation to the dairy sewage. The obtained results were used to develop a mathematical model of wet oxidation of dairy sewage, including the group of analyzed compounds.

PL

Artykuł prezentuje wyniki badań kinetycznych procesu mokrego utleniania ścieków pochodzących z przemysłu mleczarskiego. Utlenianiu poddane zostały ścieki mleczarskie o ich naturalnym pH zbliżonym do wartości 7, pobrane bezpośrednio po procesie produkcyjnym. Badania prowadzone były w okresowym reaktorze zbiornikowym z mieszadłem, przy ciśnieniu cząstkowym tlenu wynoszącym 1 MPa, w zakresie zmienności temperatury od 473 do 593 K. Oceny efektywności stopnia rozkładu związków organicznych dokonano na podstawie pomiaru wartości TOC. Celem badań było zbadanie kinetyki rozkładu związków wchodzących w skład mleka - laktozy, białek i tłuszczu oraz kinetyki przemian produktów pośrednich utleniania - lotnych kwasów tłuszczowych. Pomiar stężenia białek, tłuszczu i laktozy odbywał się z wykorzystaniem analizatora składu mleka, skalibrowanego w stosunku do ścieków mleczarskich. Otrzymane wyniki posłużyły do budowy modelu matematycznego procesu mokrego utleniania ścieków, obejmującego grupy analizowanych związków.

18

Process engineering in iron production

Pustejovska P., Jursova S.

Chemical and Process Engineering

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2013

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Vol. 34, nr 1

63--76

EN

Balance, thermodynamic and mainly kinetic approaches using methods of process engineering enable to determine conditions under which iron technology can actually work in limiting technological states, at the lowest reachable fuel consumption (reducing factor) and the highest reachable productivity accordingly. Kinetic simulation can be also used for variant prognostic calculations. The paper deals with thermodynamics and kinetics of iron making process. It presents a kinetic model of iron oxide reduction in a low temperature area. In the experimental part it deals with testing of iron ore feedstock properties. The theoretical and practical limits determined by heat conditions, feedstock reducibility and kinetics of processes are calculated.

19

Biotechnologiczne wytwarzanie kwasu bursztynowego

Piotrowska E., Szewczyk K. W., Jaworska M. M., Konieczna-Mordas E.

Inżynieria i Aparatura Chemiczna

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2012

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Nr 4

171-173

PL

Celem niniejszej pracy było modelowania fermentacji bursztynianowej prowadzonej przy użyciu bakterii A.succinogenes 130Z w reaktorze półciągłym. Sformułowany model uwzględniał inhibicję produktem oraz inhibicję substratem. Średnie wartości wynoszą: stała nasycenia Ks = 5,9 g/L, stała inhibicji produktem Kp = 32,8 g/L, stała inhibicji substratem Ki = 100,3 g/L. Stwierdzono, że w warunkach prowadzenia doświadczeń przemiana podkowa nie odgrywała roli. Model dobrze odzwierciedlał dane doświadczalne.

EN

The aim of this study was to model kinetics of succinic acid production by bacteria Actinobacillus succinogenes 130Z in a fed-batch reactor. A formulated model used in the work combined growth rate with product inhibition and substrate inhibition. Mean values of parameters were as follows: saturation constant = 5.9 g/L, product inhibition constant Kp = 32.8 g/L, substrate inhibition constant Ki = 100.3 g/L. The presented model predicts the fermentation process satisfactorily.

20

Wet Oxidation of Dairy Sewage

Piotrowska K., Imbierowicz M., Chacuk A.

Ecological Chemistry and Engineering. S

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2012

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Vol. 19, nr 1

29-38

EN

Results of kinetic studies on the process of wet oxidation of dairy sewage are presented. Experiments were carried out in a stirred batch tank reactor at the oxygen partial pressure equal to 1 MPa and at temperature ranging from 473 to 523 K. Dairy sewage was subjected to oxidation at a natural pH close to 4. The efficiency of decomposition of organic compounds was estimated on the basis of TOC measurement. The highest TOC reduction rate reached 79.6%. A kinetic model of the process was proposed and its parameters were determined experimentally. Good agreement of the experimental and calculated results was obtained.

PL

W pracy przedstawiono wyniki badań kinetycznych procesu mokrego utleniania ścieków przemysłu mleczarskiego. Badania przeprowadzono w okresowym reaktorze zbiornikowym z mieszadłem, przy ciśnieniu cząstkowym tlenu O2 P = 1 MPa, w zakresie temperatury od 473 do 523 K. Utlenianiu poddawano ścieki mleczarskie o ich naturalnym odczynie zbliżonym do wartości 4. Oceny efektywności rozkładu związków organicznych dokonano na podstawie pomiaru wartości TOC. Najwyższy stopień redukcji TOC ukształtował się na poziomie 79,6%. Zaproponowano model kinetyczny procesu i na podstawie badań eksperymentalnych określono jego parametry. Uzyskano dobrą zgodność wyników doświadczalnych i obliczeniowych.