The model for theoretical determination of composition of a heterogeneous equilibrium mixture in the course of chemical reactions: C + H2O lt = gt CO + H2 and C + 2H2 lt = gt CH4

Rad predstavlja nov način izračunavanja sastava heterogene ravnotežne mešavine hemijskih reakcija važnih u inženjerskoj praksi: proizvodnji čađi gasifikaciji ugljeva, pirolizi otpada, prečišćavanju dimnih gasova suvim i polusuvim postupcima. Rad opisuje tri načina izračunavanja i to: zasnovana na broju kilomolova, sumi broja kilomolova i izračunavanju sastava samo homogene mešavine.The work presents a new way of calculation of the composition of a heterogeneous equilibrium mixture in the course of chemical reactions important in engineering practice: soot production, coal gasification, waste pyrolysis, refining flue gases by dry and semi-dry treatments. In the available literature, the calculation of equilibrium composition of only the homogeneous (gaseous) phase is applied. This work presents three ways of calculation: based upon the number of moles, based upon the sum of the number of moles, and the calculation of the composition of only the homogeneous mixture. The reactions C + H2O ( CO + H2 and C + 2H2 ( CH4 have been considered, since in the available reference literature there is the largest number of data on the composition of the equilibrium homogeneous mixture concerning these reactions. The results of the calculation of the composition of the homogeneous (gaseous) phase, as a part of a heterogeneous mixture are identical with the results obtained by the orthodox calculation of only the homogeneous phase

The model for theoretical determination of composition of a heterogeneous equilibrium mixture in the course of chemical reactions: C + H2O lt = gt CO + H2 and C + 2H2 lt = gt CH4

Rad predstavlja nov način izračunavanja sastava heterogene ravnotežne mešavine hemijskih reakcija važnih u inženjerskoj praksi: proizvodnji čađi gasifikaciji ugljeva, pirolizi otpada, prečišćavanju dimnih gasova suvim i polusuvim postupcima. Rad opisuje tri načina izračunavanja i to: zasnovana na broju kilomolova, sumi broja kilomolova i izračunavanju sastava samo homogene mešavine.The work presents a new way of calculation of the composition of a heterogeneous equilibrium mixture in the course of chemical reactions important in engineering practice: soot production, coal gasification, waste pyrolysis, refining flue gases by dry and semi-dry treatments. In the available literature, the calculation of equilibrium composition of only the homogeneous (gaseous) phase is applied. This work presents three ways of calculation: based upon the number of moles, based upon the sum of the number of moles, and the calculation of the composition of only the homogeneous mixture. The reactions C + H2O ( CO + H2 and C + 2H2 ( CH4 have been considered, since in the available reference literature there is the largest number of data on the composition of the equilibrium homogeneous mixture concerning these reactions. The results of the calculation of the composition of the homogeneous (gaseous) phase, as a part of a heterogeneous mixture are identical with the results obtained by the orthodox calculation of only the homogeneous phase

The study on the effect of fractional composition and ash particle diameter on the ash collection efficiency at the electrostatic precipitator

Cilj eksperimentalnih istraživanja prikazanih u ovom radu jeste da se proceni stepen efikasnosti rada elektrostatičkog filtra na realnom industrijskom postrojenju (termoelektrana 'Gacko' električne snage od 310 MW, Bosna i Hercegovina) i dobijeni rezultati iskoriste za projektovanje periodičnog ili neprekidnog merenja i uporede sa rezultatima istraživanja drugih istraživača. Istraživanje performansi elektrostatičkog filtra je izvršeno u skladu sa BAS ISO 9096:2003. Efikasnost elektrostatičkog filtra je procenjena tokom uklanjanja čestica pepela u širokom opsegu veličina čestica od 1 do 250 μm. Eksploataciona iskustva ukazuju da su elektrostatički filtri efikasni za ugljeve različitog kvaliteta (prečnik čestica pepela veći od 1 ìm) i da se mogu optimizovati, kako u toku samog rada, tako i za neke naredne procese, kao što je odsumporavanje dimnih gasova. U mernim ravnima, merenja su vršena na 20 tačaka po preseku. Primećeno je da stepen uklanjanja pepela dobijen eksperimentalno (3 ispitivanja) ima približno jednake vrednosti (95,93-97,78%). Najbolje slaganje sa rezultatima eksperimentalnih ispitivanja pokazuje jednačina Deutsch-a, dok teorijski modeli Zhibin-Guoquan i Nobrega-Falaguasta-Coury ne aproksimiraju najbolje rezultate eksperimentalnih ispitivanja. Za čestice pepela prečnika manjeg od 17,5 μm ne postoji dobra korelacija između ispitivanih teorijskih modela. Najveće odstupanje modela za čestice pepela prečnika manjih od 17,5 μm je primećeno u slučaju upotrebe jednačine Deutsch-a.The goal of experimental investigations shown in this paper is to estimate the operating efficiency degree of the electrostatic precipitator on a real industrial plant (a the thermal power plant 'Gacko' with the electric power of 310 MW, Bosnia & Herzegovina) and to use the obtained results as a base of periodical engineering or continual measurement and compare them with the investigations of other investigators. The investigation of the electrostatic precipitator performance was done according to BAS ISO 9096:2003. In this paper, the electrostatic precipitator efficiency during the ash particle removal with a wide range of particle sizes from 1 to 250 μm is evaluated. The exploitational experience points out that electrostatic precipitators are efficient for the coals of different quality (coal particles with diameters bigger than 1 μm) and that they could be optimized during the exploitation itself and for some following processes (e.g., flue gas desulphurization). Within the measurement plane, the measurements were made on 20 points per section. It has been noticed that ash removal degrees obtained experimentally (3 investigations) have approximately equal value (95.93 to 97.78%). The best concordance with the results of experimental investigation shows the Deutsch equation, while theoretical models of Zhibin-Guoquan and Nobrega-Falaguasta-Coury do not correspond well to the results of experimental investigations. For the ash particles with the diameters less than 17.5 μm there is no good correlation between investigated theoretical models. The highest deviation of the model for ash particles with diameters less than 17.5 μm is notable in the case of using the Deutsch equation

Effect of temperature on a free energy and equilibrium constants during dry flue gas desulphurisation chemical reactions

During dry flue gas desulphurisation (FGD) dry particles of reagents are inserted (injected) in the stream of flue gas, where they bond SO2. As reagents, the most often are used compounds of calcium (CaCO3, CaO or Ca(OH)2). Knowledge of free energy and equilibrium constants of chemical reactions during dry FGD is necessary for understanding of influence of flue gas temperature to course of these chemical reactions as well as to SO2 bonding from flue gases

A new fuzzy risk management model for production supply chain economic and social sustainability

The issues of operational, organisational and process risk assessment in supply chains (SCs) are the most usually analysed, while other risk groups (like economic and social risks) are not taken into account, even though they have a critical effect on the competitive advantage and SCs sustainability over long time periods. The determination of risk value that may arise due to the materialisation of each defined risk factor (RF) is based on the assessment of the severity of RF consequences and frequency of RF occurrence. These judgments are obtained by decision makers and modelled by using fuzzy set theory. The relative importance of RFs are stated by fuzzy pair-wise comparison matrices in compliance with fuzzy analytical hierarchy process (FAHP). The risk level of SCs could be obtained in an exact way by applying fuzzy logic. The proposed model, to be presented in this paper, provides a possibility to easily and simply determine risk level from the automotive industry SC and to propose appropriate management initiatives that should lead to a reduction or elimination of RF influenc

Evaluation and Selection of the Quality Methods for Manufacturing Process Reliability Improvement-Intuitionistic Fuzzy Sets and Genetic Algorithm Approach

The aim of this research is to propose a hybrid decision-making model for evaluation and selection of quality methods whose application leads to improved reliability of manufacturing in the process industry. Evaluation of failures and determination of their priorities are based on failure mode and effect analysis (FMEA), which is a widely used framework in practice combining with triangular intuitionistic fuzzy numbers (TIFNs). The all-existing uncertainties in the relative importance of the risk factors (RFs), their values, applicability of the quality methods, as well as implementation costs are described by pre-defined linguistic terms which are modeled by the TIFNs. The selection of quality methods is stated as the rubber knapsack problem which is decomposed into subproblems with a certain number of solution elements. The solution of this problem is found by using genetic algorithm (GA). The model is verified through the case study with the real-life data originating from a significant number of organizations from one region. It is shown that the proposed model is highly suitable as a decision-making tool for improving the manufacturing process reliability in small and medium enterprises (SMEs) of process industry

Evaluation and Selection of the Quality Methods for Manufacturing Process Reliability Improvement-Intuitionistic Fuzzy Sets and Genetic Algorithm Approach

The aim of this research is to propose a hybrid decision-making model for evaluation and selection of quality methods whose application leads to improved reliability of manufacturing in the process industry. Evaluation of failures and determination of their priorities are based on failure mode and effect analysis (FMEA), which is a widely used framework in practice combining with triangular intuitionistic fuzzy numbers (TIFNs). The all-existing uncertainties in the relative importance of the risk factors (RFs), their values, applicability of the quality methods, as well as implementation costs are described by pre-defined linguistic terms which are modeled by the TIFNs. The selection of quality methods is stated as the rubber knapsack problem which is decomposed into subproblems with a certain number of solution elements. The solution of this problem is found by using genetic algorithm (GA). The model is verified through the case study with the real-life data originating from a significant number of organizations from one region. It is shown that the proposed model is highly suitable as a decision-making tool for improving the manufacturing process reliability in small and medium enterprises (SMEs) of process industry

One-step purification and freeze stability of papain at acidic pH values

Papain is a proteolytic enzyme of great commercial value. It is a cysteine protease highly expressed in Carica papaya fruit latex, but also present in papaya leaves. Purification procedures mostly deal with the latex and include a combination of precipitation and/or chromatographic techniques. Due to its solubility, structure and activity characteristics, the pH and salt content play significant roles in handling papain extracts. Here we report a simple, rapid and easily scalable procedure for papain purification from papaya leaves, which contain different contaminants as compared to papaya latex. Sodium chloride precipitation of contaminants at pH 5 followed by ammonium sulphate precipitation resulted in the removal of other leaf proteins and protein fragments from papain solution and about a 3-fold purification. The procedure also benefits from the suppression of autoproteolysis and preservation of the native structure, as confirmed by FTIR analysis, and the high recovery of activity of over 80%

Side asymmetry in nasal resistance correlate with nasal obstruction severity in patients with septal deformities: Computational fluid dynamics study

Objectives The objective of this study was to investigate the relationship between side asymmetry in nasal resistance (NR) and severity of the nasal airway obstruction (NAO) in patients with different types of nasal septal deformity (NSD). Design Computational fluid dynamics (CFD) study. Setting The study was conducted in a tertiary medical centre. Participants The study included 232 patients, who were referred to the CT examination of the paranasal sinuses. Exclusion criteria were sinonasal and respiratory diseases that may interfere with the nasal obstruction. The presence and the type of NSD were recorded according to the Mladina's classification. Main outcome measures The presence and severity of NAO in each patient were assessed by NOSE questionnaire. Eight computational models of the nasal cavity were created from CT scans. Models represented seven Mladina's NSD types and a straight septum of a symptomless patient. CFD calculated airflow partitioning and NR for each nasal passage. Side differences in NR were calculated by the equation increment NR = NRleft - NRright. The relationship between NOSE scores, airflow partitioning and side differences in NR was explored using Spearman's correlation analysis. Results Mladina's types of NSD showed differences in airflow partitioning and the degree of side asymmetry in NR. A significant positive correlation was detected between side differences in NR and NOSE scores (R = .762, P = .028). A significant negative correlation was found between the per cent of unilateral airflow and NR (R = -.524, P = .037). Conclusions Our results demonstrated that side asymmetry in NR could explain differences in NAO severity related to the NSD type.This is the peer-reviewed version of the article: Janović, N.; Cocić, A.; Stamenić, M.; Janović, A.; Đurić, M. Side Asymmetry in Nasal Resistance Correlate with Nasal Obstruction Severity in Patients with Septal Deformities: Computational Fluid Dynamics Study. Clinical Otolaryngology 2020. [https://doi.org/10.1111/coa.13563

The Allocation of Business Model Components under Presence of Uncertainties by the Branch-and-Bound Method

As the only constant in business is change, business transformation is essential for adopting new perspectives and business trends. One of the keys to performing successful business transformation is to be fully aware of the current components of the business model. This research aims to allocate the business model components (BMCs) to defined business model components groups (BMCGs) by developing a new approach that integrates fuzzy sets and heuristic algorithms. The allocation results enable a comprehensive analysis of business model frameworks and give a good connection to research in the domain of strategic management and business process modeling. For allocation, the decision-makers (DMs) are employing the linguistic terms modeled by the fuzzy sets theory. The considered problem is stated as an integer programming model where the optimal solution is given by a B&B algorithm. The model is tested on a sample of forty experts from four different economic sectors