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Predmet ove doktorske disertacije je istraživanje procesnih parametara vakuumskog degazatora napojne vode sa nasutom ispunom za sisteme daljinskog grejanja i formiranje originalne proračunske procedure. U disertaciji je dat pregled proračunskih procedura, dostupnih u otvorenoj literaturi, koje su danas najzastupljenije u praktičnom inženjerskom radu. Pokazano je da analizirane metodologije dovode do poddimenzionisanja aparata odnosno do aparata sa nedovoljnom visinom ispune. Na osnovu rezultata eksperimentalnih ispitivanja na industrijskom vakuumskom degazatoru, formirana je originalna korelacija za proračun koeficijenta prelaza supstancije u tečnosti predmetnog tipa aparata. Ova procedura, odnosno korelacija, može da se koristi za proračun i dimenzionisanje novih aparata, kao i za analizu rada postojećih aparata ovog tipa., The subject of this doctoral dissertation is the research of process parameters of a vacuum degasser with random packing used for water degassing in district heating systems and formation of the original design procedure. The dissertation gives an overview of the calculation procedures available in the open literature, which are the most represented in practical engineering work. It has been shown that the methodologies analyzed could lead to an undersizing of the apparatus i.e. to a insufficient height of the packed bed. Based on the experimental testing of industrial vacuum degasser, an original correlation for calculation of the mass transfer coefficient in a liquid phase of this type of apparatus has been formed. This procedure i.e. correlation, can be used for design and sizing of new equipment, as well as for performance analysis of existing equipment of this type.

SAŽETAK: Akutna hepatotoksičnost je jedan od najvećih problema farmakovigilance. Dijagnoza ovog neželjenog dejstva bi trebalo da se zasniva na kliničkim kriterijumima ali i na detekciji specifičnih biomarkera hepatocelularnog i/ili holestatskog oštećenja. Nekoliko studija je dokazalo povezanost toksičnih efekata amjodarona i aktivnosti superoksid dizmutaze (SOD). Istraživanje je sprovedeno u dva dela. Jedan je bio prospektivna kontrolisana studija, dizajnirana prema kohorti bolesnika koji imaju hepatotoksičnost i primaju amjodaron i drugi, koji je obuhvatio retrospektivno prikupljanje podataka i posledičnu analizu sa dva opservaciona dizajna, studije tipa „slučaj-kontrola“ (pojava hepatotoksičnosti) i kohortne studije (izloženost faktoru rizika-amjodaronu). Istraživanje je bilo sprovedeno u Klinici za kardiologiju, prema etičkim principima naučno-istraživačkog rada. Retrospektivnu populaciju su činili pacijenti koji su lečeni u klinici u proteklih deset godina. Podaci su bili prikupljani uvidom u istorije bolesti. Za prospektivnu, kontrolisanu studiju koristitili su se uzorci krvi bolesnika koji se leče na klinici, određivani su biomarkeri hepatotoksičnog oštećenja i genetski polimorfizam SOD2. Tokom prospektivne, kontrolisane studije korišćeni su detaljni podaci neinvazivne kliničke dijagnostike koja je od značaja za varijable istraživanja. Statistička analiza prikupljenih podataka je obuhvatila proračun veličine uzorka i statističku obradu. Primarne nezavisne varijable su bile: prisustvo Val16Ala polimorfizma (rs4880) SOD2, u prospektivnoj studiji i uzimanje amjodarona, u retrospektivnoj kohorti. Primarna zavisna varijabla je bilo prisustvo hepatotoksičnosti. S obzirom da su podaci u dostupnoj literaturi za datu populaciju oskudni i kontroverzni, rezultati predstavljaju originalni doprinos u oblasti rasvetljavanja mehanizma i značaja hepatotoksičnosti udružene sa upotrebom amjodarona kod hospitalizovanih bolesnika., Acute hepatotoxicity represents nowadays one of the greatest problems in pharmacovigilance. The diagnosis of this adverse reaction should be based on clinical criteria as well as on the detection of specific biomarkers of hepatocellular and / or cholestatic damage. Several studies have demonstrated the correlation of toxic effects of amiodarone and the activity of superoxide dizmutase (SOD). The research consisted of two parts. One was a prospective controlled study, designed according to the cohort of patients with hepatotoxicity and receiving amiodarone and the other, which included retrospective data collection and consequent analysis with two observational designs, case-control study (hepatotoxicity) and cohort study (exposure to risk factor-amiodarone). The research was conducted at the Clinic for Cardiology, according to the ethical principles of scientific research. The retrospective population consisted of patients who have been treated in the Clinic for the past ten years. The data were collected by screening the medical records of the patients. For a prospective, controlled study, blood samples of patients who are being hospitalized at the clinic were used for determination of hepatotoxic lesion biomarkers and genetic polymorphism of SOD2. During the prospective, controlled study were used detailed noninvasive clinical diagnostic data, which were important for the research variables. Statistical analysis of the collected data included a sample size calculation and statistical processing. Primary independent variables were: presence of Val16Ala polymorphism (rs4880) SOD2 in prospective study and amiodarone administration in a retrospective cohort. The primary dependent variable was the presence of hepatotoxicity. Considering the fact the data in available literature for the given population are scarce and controversial, the results will be an original contribution to the field of clarification of the mechanism and significance of hepatotoxicity as

Cilj istraživanja u okviru ove doktorske disertacije je da se jednostavnom metodom proizvede materijal od lako dostupnih sirovina, koji bi se koristio kao adsorbent za uklanjanje arsena iz vodenih rastvora..., The aim of the research in this doctoral dissertation is to use a simple method to synthesize material from readily available precursors, which would be used as an adsorbent for the removal of arsenic from aqueous solutions...

Dyes are an important class of pollutants because large amounts are often found in the environment as a result of their extensive industrial use. Traditional wastewater treatment methods often lead to high energy costs, formation of by-products, and the production of sludge. This paper analyzes the possibility of using a new, sustainable approach to water decolorization with reduced consumption of chemicals. In microreactor experiments, reactant molar ratios, volumetric flow rate, and microreactor length and diameter were varied. The obtained results showed that batch decolorization required 250-500 times higher molar ratios to achieve comparable decolorization (70-90%) and at least three times longer residence time. Microreactor experiments demonstrated that higher microreactor lengths and molar ratios influence positively the decolorization process, although satisfactory results are also achieved with medium microreactor lengths and lower molar ratios. Higher fluids velocities contribute to the decolorization process, but the best results were obtained using a medium velocity (in a 5.8m microreactor system) to achieve the highest possible mixing intensity and long enough residence time. Microreactor systems have achieved significantly better decolorization results, considering any combination of microreactor length, molar ratio, diameter, flow rate, and residence time, than a batch system. Thus, a medium length microreactor system, with a low concentration of NaOCl, low flow rate, small diameter, and medium residence time can achieve satisfactory decolorization results, but with a lower consumption of chemicals, energy, equipment, and better environmental impact. Article HighlightsColored wastewater was decolorized using batch and microreactor systems.Various microreactor lengths, diameters, and mixture velocities were tested.Microreactor system required 500 times lower amounts of decolorizing agent.

In this study, applicability of the friction theory for the viscosity estimation of pure substances and binary liquid mixtures, used in regenerative flue gas desulphurization processes, was investigated. Theory was tested on the selected solvents that have already found commercial application, tetraethylene glycol dimethyl ether, n-methyl-2-pyrrolidone and n,n-dimethylaniline, in mixtures with alcohols 1-butanol, 2-butanol or 1-hexanol. The results were compared with experimental viscosity data for eleven systems. In the calculation procedure, friction theory was coupled both with the Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) equations of state (EoS). Almost identical deviations, under 02% with both EoS, were obtained for pure compounds. For viscosity of mixtures, in almost all cases, better results were obtained using PR EoS, with values of percentage deviations less than 4%. Additionally, the possibility of simultaneous density calculations was checked and the obtained values were compared with experimental data. Application of this model for viscosity modeling of the investigated systems was justified by comparison of the obtained results with other commonly used predictive models, UNIFAC-VISCO and ASOG-VISCO.

Teorijski značaj istraživanja termodinamičkih svojstava tečnih smeša se ogleda u proširivanju baze podataka novim eksperimentalnim vrednostima i produbljivanju znanja iz teorije rastvora. U ovom istraživanju obuhvaćeni su sistemi koji sadrže industrijski važne komponente: estre i alkohole. Termodinamička i termofizička istraživanja estara su od velikog značaja zbog njihove široke primene kao veštačkih aroma, mirisa, i uopšte u industriji hrane i kozmetike, dok su alkoholi najčešće korišćeni rastvarači u industriji..., The theoretical significance of the study of thermodynamic properties of liquid mixtures is reflected in the expansion of the database due to new experimental values, and deepening of knowledge in the theory of solution. Systems included in this study are containing industrially important components: esters and alcohols. Thermodynamic and thermophysical studies of esters are of increasing interest due to their wide usage in flavoring, perfumery, artificial essences, and generally in food and cosmetic industry, while alcohols are the most commonly used industrial solvents...

The theoretical significance of the study of thermodynamic properties of liquid mixtures is reflected in the expansion of the database due to new experimental values, and deepening of knowledge in the theory of solution. Systems included in this study are containing industrially important components: esters and alcohols. Thermodynamic and thermophysical studies of esters are of increasing interest due to their wide usage in flavoring, perfumery, artificial essences, and generally in food and cosmetic industry, while alcohols are the most commonly used industrial solvents..., Teorijski značaj istraživanja termodinamičkih svojstava tečnih smeša se ogleda u proširivanju baze podataka novim eksperimentalnim vrednostima i produbljivanju znanja iz teorije rastvora. U ovom istraživanju obuhvaćeni su sistemi koji sadrže industrijski važne komponente: estre i alkohole. Termodinamička i termofizička istraživanja estara su od velikog značaja zbog njihove široke primene kao veštačkih aroma, mirisa, i uopšte u industriji hrane i kozmetike, dok su alkoholi najčešće korišćeni rastvarači u industriji...

In this paper densities, viscosities and refractive indices of four binary mixtures containing methyl ethyl ketone, at atmospheric pressure and in the temperature range from 288.15 K to 333.15 K are reported. From experimental measurements excess molar volumes, viscosity deviations and refractive index deviations are calculated and fitted to the Redlich-Kister equation. For the analysis of molecular interactions present in the mixtures, molar excess Gibbs free energies of activation of viscous flow are also calculated and fitted to the Redlich Kister polynomial equation. Experimental viscosity data are modeled by friction theory, predictive UNIFAC-VISCO and ASOG-VISCO models and correlative Teja-Rice, Grunberg Nissan, McAlister, Eyring-UNIQUAC and Eyring-NRTL models. The new CO-CH2O and CO pyridine interaction parameters are determined for their application in the UNIFAC-VISCO and ASOG-VISCO models.

This research focuses on the modeling of the liquid-liquid dispersed system, including particular insight on the electrocoalescence (EC) process that occurs during the breaking of double emulsions. The representative system, used in this work, was taken from the pilot plant for solvent extraction of uranium from wet phosphoric acid. The chosen framework required for elucidation of the EC process is based on the electrohydrodynamic (EHD) principles. During the model development it was necessary to consider several theoretical concepts for easier understanding and description of the related events. The first is the concept of entities, and corresponding classification of finely dispersed systems. The second concept is an introduction of almost forgotten basic electrodynamics element the memdiode or memristor as a current controlled device, and corresponding memristive systems. Hence, the conclusions that may be withdrawn from the presented results and findings could enable easier designing of the solutions for a breaking of double emulsions problems, that is, the entrainment problems that may arise in some pilot or industrial plants. Finally, the perspectives and the remaining challenges, considering the here discussed concepts and model based on the EHD principles, are mentioned.

Carbon cryogel/ceria composite, with 10 wt.% of ceria, was synthesized by mixing of ceria and carbon cryogel (CC). The sample was characterized by field emission scanning electron microscopy, nitrogen adsorption and X-ray diffraction. The adsorption of arsenic(III) ions from aqueous solutions on carbon cryogel/ceria nanocomposite was studied as a function of time, solution pH and As(III) ion concentration. The results are correlated with previous investigations of adsorption mechanism of arsenic(III) on carbon cryogel. Adsorption dose experiments showed that the mass of the adsorbent was reduced for 20 times, in comparison with pure CC, for the same amount of adsorbed arsenic(III) ions. BET isotherm was used to interpret the experimental data for modelling liquid phase adsorption.

Waste disposal is an important element of integrated waste management. In order to dispose of waste that is free of environmental risk, the proper design of landfills during their construction and/or closure is necessary. The first section of the paper presents the current state of landfills in Serbia, the second deals with problems in project design of landfills, especially in regard to their: a) program of waste disposal; b) impermeable layer; c) leaching collection and treatment; and d) gas collection and treatment. Analysis shows that many modern landfills in Serbia do not meet environmental protection requirements, therefore, they need reconstruction. All existing landfills owned by municipalities, as well as illegal dump sites, should be adequately closed. This paper presents the guidelines for successful landfill design which are to serve to meet the requirements and recommendations of Serbian and European regulations. Sound design of landfill technological elements should insure full sustainability of landfills in Serbia., Deponovanje otpada je element integrisanog upravljanja otpadom. Valjano izrađeni projekti izgradnje i/ili zatvaranja deponije osiguravaju bezbedno odlaganje otpada, uz minimalne negativne uticaje na životnu sredinu. U prvom delu rada izvršen je pregled i analiza deponija u Republici Srbiji. U drugom delu rada, u funkciji analize, opisani su značajni elementi tehnološkog projektovanja savremenih deponija koji uključuju: a) program deponovanja, b) obezbeđivanje vodonepropusnosti dna i prekrivnog sloja, c) sakupljanje i tretman procednih voda i d) sakupljanje, tretman i iskorišćenje deponijskog gasa. U radu je konstatovano da postojeće, savremene deponije nisu u potpunosti projektovane u skladu sa propisima, te da je neophodna njihova rekonstrukcija. Takođe, postojeća smetilišta i divlje deponije neophodno je zatvoriti i sanirati. U ovom radu predstavljene su smernice za valjano tehnološko projektovanje deponija koje su u funkciji ispunjavanja zahteva i preporuka nacionalnih i evropskih propisa.

Densities, refractive indices and viscosities of three binary systems consisting of ethyl lactate with methyl ethyl ketone (MEK) or toluene or n-methyl-2-pirrolidone (NMP) were measured at eight temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15) K and atmospheric pressure. From these data, excess molar volumes, deviations in refractive indices and viscosity deviations were calculated and correlated with the Redlich-Kister equation. The obtained results for excess molar volume have been used for analysis of specific molecular interactions between mixture components and the influence of temperature on them. In addition the modeling of V-E binary data was performed with the Peng-Robinson-Stryjek-Vera cubic equation of state (PRSV CEOS) coupled with the van der Waals (vdW1) and CEOS/G(E) mixing rules. The refractive indices of binary mixtures were predicted by various mixing rules and compared with experimental data. The viscosity modeling was done by UNIFAC-VISCO and ASOG-VISCO models, which could be used as predictive if all interaction parameters between functional groups are known, and purely correlative Eyring-UNIQUAC, Eyring-NRTL, Teja-Rice, Grunberg-Nissan and McAlister equations. Due to the high importance of models for viscosity prediction, the experimental values presented in this work, but also the data obtained in previous as well as in ongoing investigations, were used to determine the unknown interaction parameters of several functional groups for their application in the UNIFAC-VISCO and ASOG-VISCO models.

Viscosities of ten binary liquid mixtures consisting of ionic liquids and organic compounds, determined at atmospheric pressure and in a wide temperature range, were calculated using two different approaches, predictive by group contribution models (UNIFAC-VISCO and ASOG-VISCO) and correlative (Seddon, Grunberg-Nissan, McAlister, Eyring-UNIQUAC and Eyring-NRTL models), and compared using literature data. The obtained results were analysed in terms of the applied approach and model. For UNIFAC-VISCO and ASOG-VISCO predictive models, the literature viscosity data were used to determine new interaction parameters.

Software for chemical processes modeling and simulation, in the past few decades, plays an important role in the development of chemical-process industry with its growing capabilities and wide range of application. Usage of process simulators in Serbia for the process design is very limited. This paper gives a brief overview of the numerous process simulators that are used in the chemical-process industry today. The conceptual design is responsible for most of the investment costs in chemical process industry. Importance of precise design on preliminary level is obvious. Wrong decisions made at the conceptual level could be carried out throughout the chain in process design to the detailed design procedures and procurement of equipment. Although preliminary design phase comprises only about 2% of the total cost of the project, it contributes significantly to the reduction of cost of the project by more than 30%. Therefore process simulators play important role in elimination of unnecessary errors in basic process design. Here is also shown a case study of parallel process simulated in different process simulators which tests the results, the reliability and usefulness of these programs in solving specific engineering tasks. Comparison of given simulation results confirm that the modern process simulators are at high level of confidence, no matter they are based on different models, equations, methods, operations, interfaces or data bases. Usage of software speeds up the arrival of optimized solution during the design and the operational procedures. Therefore software has significant impact on reducing time of pre-project phase such as research, conceptual design, and proving project abilities. Its development leads to the faster commercialization of industrial ideas., Softveri za modelovanje i simulaciju tehnoloških procesa u poslednjih nekoliko decenija imaju značajnu ulogu u razvoju procesne industrije. Korišćenje procesnih simulatora,u našoj zemlji, za potrebe projektovanja tehnoloških procesa nije široko rasprostranjeno, a literatura je nedovoljna. U ovom radu je dat pregled savremenih procesnih simulatora i prikazane su njihove mogućnosti za projektovanja procesa u zavisnosti od grane hemijske industrije. Prikazna je studija slučaja tehnološkog procesa u više procesnih simulatora koja ispituje rezultate, pouzdanost i upotrebljivost ovih programa prilikom rešavanja konkretnih projektantskih zadatka na primeru postrojenja za separaciju prirodnog gasa. Date su uporedne karakteristike rezulata simuliranja separacije prirodnog gasa za potrebe projektovanja procesa, na osnovu simulacija u softverima različitih složenosti i kvaliteta. Procesni simulatori su pokazali svoju upotrebnu vrednost kao značajan oslonac projektantima, iako rezultati koje su pokazali međusobno imaju značajna odstupanja.

Landfills are complex systems that could potentially contaminate the environment. This needs to be prevented by providing impermeability during the landfill design. In this aim, the related regulations should be followed and adequate materials that provide impermeability should be used. The first part of the paper presents a review of the current regulations, interpretations, and recommendations from the U.S., EU and Republic of Serbia. Knowing that the Serbian regulation should fully follow the related European Directive, some inadequate formulations and terms were observed in the analyses related to the Directive Annex I, 3.2. Request of the Regulation that deals with the bottom of the landfill leakage is formulated differently than in the Directive as well. The mentioned problems enable some design solutions that are not among the best available techniques. In the second part, the paper presents a comparative analysis of possible alternatives in impermeable layer design, both for the bottom and landfill cover. Some materials like clay, CCL, GCL might not be able to satisfy the prescribed requirements. The longest lifetime and the lowest coefficient of permeability, as well as excellent mechanical, chemical and thermal stability, show the mixture of sand, bentonite and polymers (PEBSM)., Deponije predstavljaju složen sistem koji potencijalno može zagaditi životnu sredinu, što se sprečava obezbeđenjem vodonepropusnosti prilikom njihovog projektovanja. Prvi deo preglednog rada bavi se analizom odgovarajućih tehničkih propisa, tumačenja i preporuka iz SAD, EU i Srbije, u cilju podsticanja valjanog usaglašavanja domaće prakse i propisa sa najboljim dostupnim tehnikama na međunarodnom nivou. U drugom delu rada uporedno su analizirane alternative prilikom projektovanja vodonepropusnih slojeva za oblaganje dna i prekrivanje deponija. Opisane su slabosti i prednosti korišćenja prirodne gline, bentonita, geosintetičke glinene obloge i različitih mešavina peska, bentonita i polimera. Rad zaključno formuliše predlog unapređenja nacionalnog propisa o odlaganju otpada na deponije.