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Environmental management concepts supported by information technology

Environmental management concepts supported by information technology

The genesis and development of environmental management concepts are presented. An overview of the current environmental management ideas, programmes and systems, including Sustainable Development, Responsible Care, Cleaner Production, environmental management based on ISO 14000, and EMAS is provided. Selected computer-aided tools and techniques for improving the quality of environmental management are proposed.

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Evaluation of ground pollution by hydrocarbons using Rock-Eval pyrolysis

sediments. Org. Geochem. 86, 71–80. DOI: 10.1016/j.orggeochem.2015.06.009. 13. Carrie, J., Sanei, H. & Stern, G. (2012). Standardisation of Rock-Eval pyrolysis for the analysis of recent sediments and soils. Org. Geochem. 46, 38–53. DOI: 10.1016/j.orggeochem.2012.01.011. 14. Hetényi, M. & Nyilas, T. (2014). Soil organic matter characterization using S3 and S4 signals from Rock-Eval pyrolysis. Pedosphere 24(5), 563–574. 15. Hetényi, M., Nyilas, T. & Toth, T.M. (2005). Stepwise Rock-Eval pyrolysis as a tool for typing heterogeneous organic matter in

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CFD modelling of hydrogen starvation conditions in a planar Solid Oxide Fuel Cell

Abstract

The aim of this study was to highlight the interest of using CFD technique as a diagnostic tool of a malfunctioning Solid Oxide Fuel Cells. Hydrogen starvation of a SOFC due to nitrogen dilution is one of the cell dysfunctions and can lead to its degradation. Identification of the starvation point allows to improve cell performance and establish the best conditions for degradation tests. To illustrate a potential of the CFD tool, several simulations of a single planar SOFC and its behaviour under hydrogen starvation were performed and analysed. The results showed that at lower cell voltage values of 0.3 and 0.5 V significant gradients in the electric current were noticed due to a local reduction in hydrogen concentration. The CFD analysis allowed defining desirable mass flow rate of hydrogen to SOFCs to avoid fuel starvation. The model constitutes a helpful tool for optimizing cell design and operational conditions.

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Mechanical properties evaluation and ultrasound diagnosis of unsaturated polyester-glass pipes

Abstract

The purpose of the present work was the elaboration of research methodology of the exhaustion degree of performance properties of pipes based on unsaturated polyester and glass fibers, which were manufactured by the cross winding method on a poly(vinyl chloride) core. Within the frame of the work we conducted fatigue-ageing tests being the simulation tool of the degradation process of polyester-glass pipes. Diagnosis of the composite material condition was conducted with the use of nondestructive ultrasonic testing with the application of the echo method, in which the transition time of ultrasonic wave was determined as the identifying parameter. The registered transition time of ultrasonic wave allowed the identification of the material condition during the course of pipes exploitation.

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Model development of integrated CPOx reformer and SOFC stack system

Abstract

The main purpose of this study was to develop a mathematical model, in a steady state and dynamic mode, of a Catalytic Partial Oxidation (CPOx) reformer – Solid Oxide Fuel Cell (SOFC) stack integrated system in order to assess the system performance. Mass balance equations were written for each component in the system together with energy equation and implemented into the MATLAB Simulink simulation tool. Temperature, gas concentrations, pressure and current density were computed in the steady-state mode and validated against experimental data. The calculated I–V curve matched well the experimental one. In the dynamic modelling, several different conditions including step changes in fuel flow rates, stack voltage as well as temperature values were applied to estimate the system response against the load variations. Results provide valuable insight into the operating conditions that have to be achieved to ensure efficient CPOx performance for fuel processing for the SOFC stack applications.

Open access
Statistical modeling of copper losses in the silicate slag of the sulfide concentrate smelting process

Abstract

This article presents the results of the statistical modeling of copper losses in the silicate slag of the sulfide concentrates smelting process. The aim of this study was to define the correlation dependence of the degree of copper losses in the silicate slag on the following parameters of technological processes: SiO2, FeO, Fe3O4, CaO and Al2O3 content in the slag and copper content in the matte. Multiple linear regression analysis (MLRA), artificial neural networks (ANNs) and adaptive network based fuzzy inference system (ANFIS) were used as tools for mathematical analysis of the indicated problem. The best correlation coefficient (R2 = 0.719) of the final model was obtained using the ANFIS modeling approach.

Open access
Uncertainty analysis of the kinetic model of natural gas combustion in IC Engine

References Rabitz, H., Kramer, M. & Dacol, D. (1983). Sensitivity analysis in chemical kinetics. Annals of Rev. Phys. Chem. 34, 419-461. Turianyi, T. (1990) Sensitivity analysis of complex kinetic systems: tools and applications. J. Math. Chem. 5, 203-248. Radhakrishnan, K. (1990). Numerical approaches to combustion modelling. In Progress in Astronautics and Aeronautics, vol. 135, pp. 83-128, eds Oran E. S., and Boris J. P. AIAA, Washington

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CFD modelling of two-phase liquid-liquid flow in a SMX static mixer

CFD modelling of two-phase liquid-liquid flow in a SMX static mixer

The paper provides an overview of the application of Computational Fluid Dynamics tools for predicting transport processes in two-phase flow in a SMX static mixer. The overview is achieved by taking a brief look at factors: mesh generation, development of sub-models, post-processing including validation and quantitative verification of CFD results with experimental data. Two types of numerical approach were used in the simulations: the Reynolds averaged Navier-Stokes in the steady-state mode with the standard k-??turbulence model and Large Eddy Simulations in the unsteady mode. Both CFD techniques were applied to calculate flow velocities, pressure drop and homogenisation level in a SMX static mixer of the liquid-liquid mixture. The steady state drop size distribution was obtained by implementation procedure containing the population balance equation, where transport equations for the moments of the drop size distribution are solved and the closure problem is overcome by using the Quadrature Method of Moments.

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ANFIS based prediction of the aluminum extraction from boehmite bauxite in the Bayer process

Abstract

This paper presents the results of nonlinear statistical modeling of the bauxite leaching process, as part of Bayer technology for alumina production. Based on the data, collected during the year 2011 from the industrial production in the alumina factory Birač, Zvornik (Bosnia and Herzegovina), nonlinear statistical modeling of the industrial process was performed. The model was developed as an attempt to define the dependence of the Al2O3 degree of recovery as a function of input parameters of the leaching process: content of Al2O3, SiO2 and Fe2O3 in the bauxite, as well as content of Na2Ocaustic and Al2O3 in the starting sodium aluminate solution. As the statistical modeling tool, Adaptive Network Based Fuzzy Inference System (ANFIS) was used. The model, defined by the ANFIS methodology, expressed a high fitting level and accordingly can be used for the efficient prediction of the Al2O3 degree of recovery, as a function of the process inputs under the industrial conditions.

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Investigation of the toxicity of the ionic liquid 1-butyl-3-methylimidazolium chloride to Saccharomyces cerevisiae AY93161 for lignocellulosic ethanol production

Ionic liquid (IL) pretreatment of lignocellulosic materials has provided a new technical tool to improve lignocellulosic ethanol production. To evaluate the influence of the residual IL in the fermentable sugars from enzymatic hydrolysis of IL pretreatment of lignocellulosic materials on the subsequent ethanol fermentation, the toxicity of the IL 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) to Saccharomyces cerevisiae AY93161 was investigated. Firstly, the morphological structure, budding and metabolic activity of Saccharomyces cerevisiae AY93161 at different [BMIM]Cl concentrations were observed under an optical microscope. The results show that its single cell morphology remained unchanged at all [BMIM]Cl concentrations, but its reproduction rate by budding and its metabolic activity decreased with the [BMIM]Cl concentration increasing. The half effective concentration (EC50) and the half inhibition concentration (IC50) of [BMIM]Cl to Saccharomyces cerevisiae AY93161 were then measured using solid and liquid suspension culture and their value were 0.53 and 0.39 g.L-1 respectively. Finally, the influence of [BMIM]Cl on ethanol production was investigated. The results indicate that the [BMIM]Cl inhibited the growth and ethanol production of Saccharomyces cerevisiae AY93161. This toxicity study provides useful basic data for further development in lignocellulosic ethanol production by using IL technology and it also enriches the IL toxicity data.

Open access