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Rezultatele pentru velocityRezultate gasite: 50
Polyelectrolyte - surfactant complexes used in the coagulation floculation processes
Environmental Engineering and Management Journal › Vol. 7 › Nr. 1 AbstractThe removal of formasine fines particles from water by precipitation with polyelectrolyte and surfactant complex of Polyacrylamide (industrial product Praestol 611 made by Degussa) and Sodium Lauryl Sulphate (SLS) was experimentally studied. Calcium oxide was added to initiate precipitation of the polyelectrolyte complex together with the fines particles. The experiments were carried out with complexes having the surfactants concentration higher then the critical aggregation concentratio... Autori: Cristina Costache, Gabriel Dabija, Mihaela Mihai ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25238
Triphasic external-loop airlift reactors. Hydrodynamic and dispersion studies
Environmental Engineering and Management Journal › Vol. 7 › Nr. 3 AbstractConsidering that three-phase dispersions are common in chemical engineering and biotechnology, and with increasing airlift reactor applications to chemical and biotechnological processes, a experimental study was undertaken in order to investigate the liquid phase hydrodynamics and dispersion in an external-loop airlift reactor on laboratory scale. Experiments were conducted in order to find a relationship between relevant hydrodynamic and mixing parameters of a solidsuspended exter... Autori: Florina Ungureanu, Maria Gavrilescu, Radu Z. Tudose ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25268
Distribution of oxygen transfer rate in stirred bioreactors with simulated broths
Environmental Engineering and Management Journal › Vol. 7 › Nr. 3 AbstractThe study on distribution of oxygen transfer rate for a stirred bioreactor and simulated broths was carried out for four positions inside the broth and indicated the significant variation of kla on the bioreactor height. For all considered positions, kla initially increased to a maximum value with mixing intensification, decreasing then, as the result of the modification of mixing mechanism in presence of air bubbles. The increase of broth viscosity led to the significantly reducing of o... Autori: Adina Segneanu, Anca-Irina Galaction, Dan Caşcaval, Radu Z. Tudose ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25270
Mathematical modeling of gas drying by adsorption
Environmental Engineering and Management Journal › Vol. 7 › Nr. 3 AbstractTheoretical and experimental studies of gas drying processes by adsorption in fixed bed of grains are presented in this paper. Based on an extensive literature study, some of the most representative mathematical models describing gas adsorption in fixed bed and consequently gas drying processes by adsorption in fixed bed are also presented. Using a mathematical model from those mentioned describing adsorption under isotherm regime, the temperature and gas flow velocity effects over the d... Autori: Marius Sebastian Secula, Stelian Petrescu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25272
Analysis of distribution of oxygen transfer rate in stirred bioreactors for bacterial broths
Environmental Engineering and Management Journal › Vol. 8 › Nr. 1 AbstractThe study on the distribution of oxygen transfer rate in a stirred bioreactor for Propionibacterium shermanii broths underlined the major influence of the presence and concentration of biomass on the interphasic transfer of oxygen. Owing to the bubbles surface blockage by the bacterial cells, the accumulation of biomass from 30.5 to 120.5 g/l d.w. led to the decreasing of kla for about 1.3- 2.4 times. Compared with the simulated broths without biomass having similar apparent viscosity, t... Autori: Adina Segneanu, Anca-Irina Galaction, Dan Caşcaval ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25364
Comparative study of the adsorption-desorption cycles of hexane over hypercrosslinked polymeric adsorbents and activated carbon
Environmental Engineering and Management Journal › Vol. 9 › Nr. 1 Abstract
In this work, the behavior of n-hexane vapors in the adsorption-desorption cycles of non-functionalized polymeric adsorbents (MN 202 and MN 250) and granular activated carbon (AC 20) was studied. The adsorption experiments were performed in a fixed bed column, under dynamic conditions, at 30?C and atmospheric pressure. The inlet concentration of n-hexane in the air streams was 0.115 mg/cm3 (32500 ppm) and the space velocity was 2.75 s-1. Also, desorption experiments were performed in... Autori: Adela Marilena Buburuzan, Cezar Catrinescu, Matei Macoveanu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25584
NUMERICAL SIMULATION OF HEAT TRANSFER IN DIRECTIONAL SOLIDIFICATION PROCESS FOR POLYCRYSTALLINE SILICON
Environmental Engineering and Management Journal › Vol. 10 › Nr. 6 Temperature distribution in the vacuum directional solidification system influenced seriously on the impurities concentration andmicrostructure in Polycrystalline Silicon. In this study, a numerical model for the transient global heat transfer for directionsolidification process has been developed by the finite element method (FEM). A two-dimension numerical simulation fortemperature distribution of directional solidification process was carried out using software Multi-physics Comsol 3.5a. Ther... Autori: Guoqiang Lv, Wenhui Ma, Hua Wang, Xiangyang Mei, Kuixian Weihttp://www.ecozone.ro/reviste.php?RID=25671
PARAMETERS EFFECT ON THE PRODUCT DISTRIBUTION IN THE BIOMASS TO FISCHER-TROPSCH FUELS PROCESS
Environmental Engineering and Management Journal › Vol. 10 › Nr. 9 Abstract:The increasing of energy consumption and fossil fuel emissions (especially CO2, SO2 and NOx) and the limitation of crude oilreserves, determined a growing trend toward renewable energy technologies, like solar, wind, geo-thermal energy and biomass forbiofuels.From all the renewable energies sources, biomass attracts more and more interest being a renewable resource with economicpotential, which can be found all over the world, with positive environmental properties due to neutral emissi... Autori: Anca Sauciuc, Angela Potetz, Georg Schlaub, Gerald Weber, Hermann Hofbauer, Lucia Dumitrescu, Reinhard Rauch, Ziad Abosteif ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25762
NUMERICAL INVESTIGATION ON CONVECTIVE HEAT TRANSFER IN HIGH TEMPERATURE SOLAR RECEIVER
Environmental Engineering and Management Journal › Vol. 10 › Nr. 10 Abnstract:In recent years, solar receivers have been employed in several applications where high temperature fluids are involved, such aspower plants and solar thermal reactor. The possible presence of high temperature gradients could determine reduced receiverefficiency and a short life of the material. Thermal and fluid dynamic analysis of the receiver allows to highlight possible presenceof temperature gradients and to evaluate their values and the more critical zone of the material. Compress... Autori: Alina Adriana Minea, Oronzio Manca, Salvatore Tamburrino, Sergio Nardini ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25779
BIOLOGICAL AIR TREATMENT EFFICIENCY OF A STRAW BIO-CHARGE
Environmental Engineering and Management Journal › Vol. 10 › Nr. 10 Abstract:Experimental research evaluated the possibilities of air treatment efficiency of a cylindrically shaped bio-charge, namely straw, toremove volatile organic compounds from the air. As determined during experiments, the air treatment efficiency of the straw biochargefor acetone removal reached 97.3%, while for butanol removal the efficiency was 86.0%. It has been determined that, withvolatile organic compound concentrations increasing biological air treatment efficiency is decreasing as h... Autori: Alvydas Zagorskis, Petras Vaitiekunas, Pranas Baltrenas, Raimondas Leopoldas Idzelis, ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25790
MATHEMATICAL MODELS TO SUPPORT POLLUTION COUNTERACTION IN CASE OF ACCIDENTS
Environmental Engineering and Management Journal › Vol. 11 › Nr. 1 This paper presents a mathematical model for the prediction of pollutant transport in rivers. The model has been developed and calibrated using the Matlab software and relying on field data from Romanian Someş River (collected in case of accidental cyanide release). Field data has been used to estimate model parameters (e.g. dispersion coefficient, velocity) as variable in time and space in order account for river features non-uniformity in time and also in space. These initial parameter va... Autori: Elisabeta-Cristina Ani, Vasile Mircea Cristea, Paul Serban Agachi ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25848
REPRESENTATION OF 3D ATMOSPHERIC DATA USING A MULTI-STAGE VISUALIZATION PIPELINE
Environmental Engineering and Management Journal › Vol. 12 › Nr. 6 AbstractThe representation of relevant information from data generated through atmospheric imaging is of substantial importance toenvironmental sciences, meteorology, as well as in weather hazard predictive models for disaster prevention. As the techniquesfor the acquisition of such data have progressed and grown in complexity, so have the visualization algorithms required to processthe related data and to produce images or animations of the underlying information. To this extent, we present a g... Autori: Marius Gavrilescu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26001
CFD MODELING AND SIMULATION OF A SURFACE WATER TREATMENT PILOT PLANT
Environmental Engineering and Management Journal › Vol. 12 › Nr. 5 AbstractThe hydrodynamics of two equipments from a surface water treatment pilot plant has been investigated through residence timedistribution (RTD) experiments using brine solution as tracer. Computational Fluid Dynamics (CFD) procedure, which isincreasingly utilized to study a wide variety of complex environmental fluid mechanics processes, was used to predict the flowpatterns and other properties of flowing fluids (e.g. velocity, concentration of species etc.). In this work, ANSYS Fluent 14.... Autori: Adina Pacala, Alain Liné, Alexandru-Dan Filep, Cosmina-Mariana Militaru, Teodor Todinca ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26030
CHALLENGES FOR 2D WATER QUALITY MODELLING OF LAKE TAIHU IN CHINA
Environmental Engineering and Management Journal › Vol. 12 › Nr. 5 AbstractLake Taihu is a shallow, wind-driven lake where eutrophication is always a serious problem. The study presented hereininvestigates the effect of wind on the eutophication of the lake, by using a two-dimensional (2D) hydrodynamic model coupledwith a 2D water quality model. The 2D water quality model looks in particular at the water quality situation of Lake Taihu in theyear 2008 and predicts future changes in the algae bloom situation. The Delft3D modelling tool was used to build thehydro... Autori: Arthur Mynett, Chao Yue, Ioana Popescu, Leo Postma, Quan Pan ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26037
MODELING THE IMPACTS OF HUMAN ACTIVITIES ON WATER QUALITY OF JIJIA RIVER
Environmental Engineering and Management Journal › Vol. 12 › Nr. 4 AbstractQuality of water bodies is influenced by their ability to self-clean and disperse the existing substances in water originating fromnatural or anthropogenic sources. Creating mathematical models, using design software and simulation, in terms of surface waterquality monitoring, are standard design and interpretation of studies necessary for rational management of water resources. Andwe must respect the concept of "sustainable development”. In this paper we highlight this by modeling data ... Autori: Florentin Nacu, Ion Giurma, Valentin Boboc ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26056
BEHAVIOUR OF SOLID PARTICLES ON A FLAT OSCILLATING SURFACE
Environmental Engineering and Management Journal › Vol. 12 › Nr. 1
Abstract
In many industrial applications most of the solid particles are separated by size and for this purpose there are used the oscillating
sieves. The separation process based on sieves is a complex one and it depends on several factors, such as the properties of solid
particles submitted to the separation process and on the operating regimes of the separating equipment. We have studied the
separation process of the behaviour of solid particles on a flat oscillating surface... Autori: Ovidiu Bontas ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26134
DEMINERALIZATION OF WATER WITH MIXED-LAYER ION-EXCHANGERS
Environmental Engineering and Management Journal › Vol. 12 › Nr. 1
Abstract
This paper develops a procedure whereby breakthrough curves obtained experimentally for ion exchange process in fixed bed ion
mixed exchangers during water demineralization, can be used to characterize quantitatively and optimize the ion exchange
process. In this regard, based on breakthrough curves there were developed statistical models that correlate three important factors
which influence the process (superficial fluid velocity through the layer, changing layer height,... Autori: Iuliana Rogoveanu Radosavlevici ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26147
DYNAMIC MECHANICAL COMPRESSION OF ROCK MATERIAL WITH DIFFERENT WEATHERING DEGREES
Environmental Engineering and Management Journal › Vol. 12 › Nr. 9 AbstractRock dynamic mechanical characteristic is the basic information to study the damage of rock structures under dynamic loadsinduced from earthquake or blasting. A nuclear power plant site is a granite mountain of the same active tectonic period. Dynamic triaxial compression experiments need to be conducted on the drill cores of different project parts according to the design requirements. These drill cores were formed in the same active tectonic period, but as a result of the different bur... Autori: Liu Bo ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26163
EXPERIMENTAL INVESTIGATION ON WET FLUE GAS DESULFURIZATION WITH ELECTROSTATICALLY-ASSISTED TWIN-FLUID ATOMIZATION
Environmental Engineering and Management Journal › Vol. 12 › Nr. 9 AbstractA wet flue gas desulfurization (WFGD) system adopting electrostatically-assited twin-fluid atomization injector was presented.Spatial distributions of the droplet sizes, velocity for different voltages were measured using limewater and SO2 removalefficiency for different voltages and Ca/S ratios were tested using limewater drops. The physical and chemical improvementmechanisms were analyzed using spray characteristics and double film theory. The analysis showed that electrostatically-ass... Autori: Zhentao Wang ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26175
EXPERIMENTAL INVESTIGATION AND CFD SIMULATION OF THE HYDRODYNAMIC AND MASS TRANSFER CHARACTERISTICS IN A SPLIT-CYLINDER AIRLIFT REACTOR CONTAINING PETROLEUM-WATER MICRO-EMULSIONS
Environmental Engineering and Management Journal › Vol. 12 › Nr.12 AbstractIn this article, hydrodynamic parameters and overall Oxygen mass transfer coefficient of petroleum based micro-emulsions in anairlift reactor were investigated. Four different petroleum-in-water micro-emulsion systems containing kerosene, heavy naphtha,light naphtha and diesel as oil based were used with concentrations of 3% and 7 % (v/v). The experimental data were supportedby simulation results obtained from the Computational Fluid Dynamics (CFD) method. The CFD was properly able to si... Autori: Mostafa Keshavarz Moraveji ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26234
SOLID MATERIAL MOTION LAW IN VERTICAL FEEDING SYSTEM WITHIN FULLY MECHANIZED COAL MINING AND BACKFILLING TECHNOLOGY
Environmental Engineering and Management Journal › Vol. 13 › Nr. 1 AbstractBased on principles of feeding solid waste into vertical boreholes in fully mechanized coal mining and backfilling technology,the literature established a trajectory model of particles in gas-solid two-phase flow for the sake of reducing the damage tostorage silo underground done by enormous impulsive force generated by falling solid waste. In addition, dynamical analysismethod in gas-solid two-phase flow field was adopted herein to study the solid particles’ force characteristics and th... Autori: Nan Zhou ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26271
NUMERICAL AND EXPERIMENTAL STUDY ON THE THERMO-AERODYNAMIC BEHAVIOR OF A DOUBLE-SKIN GLAZED FAÇADE
Environmental Engineering and Management Journal › Vol. 13 › Nr. 4 AbstractThis paper presents a study of the thermoaerodynamic spectrum inside an asymmetrically heated vertical channel of a doubleskinfaçade. A double-skin façade is an envelope construction that consists of two transparent surfaces separated by an airchannel. The numerical modeling was developed using the Ansys-Fluent simulation software under conditions of forcedconvection, using a three-dimensional geometry and a “k-ε standard” turbulence model. Then, experimental tests were performedon ... Autori: Cătălin George Popovici, Cătălin Grigoraş, , Theodor Mateescu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26332
KINETIC STUDY OF PHENOL REMOVAL FROM WASTEWATER OVER A 0.5% Pt/ γ-Al2O3 CATALYST IN A TRICKLE BED REACTOR
Environmental Engineering and Management Journal › Vol. 13 › Nr. 5 AbstractCatalytic wet oxidation (CWO) of phenol was studied in the present work. The effect of liquid hourly space velocity (LHSV),superficial gas velocity, reactor pressure, temperature and initial phenol concentration on phenols removal was investigated.Results showed that phenol conversion increased with increasing reaction temperature, reactor pressure, and superficial gasvelocity of oxygen, yet it decreased with increasing (LHSV). The results exhibited that the highest phenol conversion of(... Autori: Farah T. Jasim, Luma S. Ahmed, Mohammad F. Abid ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26381
PERFORMANCE EVALUATION OF ANIONIC POLYMER-CATIONIC SURFACTANT COMPLEX COAGULANTS IN WATER TREATMENT
Environmental Engineering and Management Journal › Vol. 13 › Nr. 8 AbstractThe performance of some complex coagulants derived from weak and medium anionic polymers and medium cationic surfactantin coagulation-flocculation process for water treatment was experimentally investigated by carrying out kinetic studies and bydetermining the optimum coagulant dose. The complex coagulants were prepared from weak anionic and medium anioniccopolymers of acrylamide and sodium acrylate with the commercial names Praestol 2515 and Praestol 2540, and mediumcationic surfactant ... Autori: Constantin Bobirică ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26478
RESEARCH ON PARAMETERS CHANGES OF THE TWO-LEVEL MULTICHANNEL CYCLONE
Environmental Engineering and Management Journal › Vol. 13 › Nr. 9 AbstractThe conducted research has proved the dependence of gas flow rate in the separate channels of the two-level multichannel cycloneat a different inflow velocity and the number of channels. The carried out investigation demonstrates the dependence of changesin velocity in the channels under varying relations between peripheral and transitional flows. The work of a cyclone of the channelis based on centrifugal forces and an additionally occurring filtration process caused by the interaction ... Autori: Pranas Baltrėnas ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26488
METHOD FOR THE DETERMINATION OF ELECTRIC PERMITTIVITY OF AIR POLUTANTS EFFECTIVE IN HEAT TRANSPORT
Environmental Engineering and Management Journal › Vol. 13 › Nr. 9 AbstractThe objective of this study is air pollutants discharging on active centers, depending on its relative electric permittivity, effectivein thermal, chemical and mechanical hydrogen relaxation enabling the fastest velocity of pollutant heat transport. The diagnosticsof relative electric permittivity is carried out on the basis of the daily pollutants mass concentration monitoring results, in sixthday period in the various seasons and locations in Romania and Serbia. The monitoring results ... Autori: Milan Pavlović ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26507
UNCERTAINTY IN CALCULATING AIR EXCHANGE RATE OF NATURALLY VENTILATED DAIRY BUILDING BASED ON POINT CONCENTRATIONS
Environmental Engineering and Management Journal › Vol. 13 › Nr. 9 AbstractAccurate quantification of gaseous emissions from livestock buildings to the atmosphere requires accurate determination of theventilation rate and the representative gas concentration in the exhaust air. But there is a lack in the investigation of reasons anduncertainties for selecting sampling points and locations in naturally ventilated dairy (NVD) buildings. The objective of thisstudy was to investigate uncertainties in calculating AER based on carbon dioxide (CO2) balance method. The... Autori: Chayan K. Saha ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26515
OPTIMIZING THE NANOFILTRATION OPERATING CONDITIONS AS POST TREATMENT STEP IN THE GROUNDWATER DENITRIFICATION PROCESS
Environmental Engineering and Management Journal › Vol. 13 › Nr. 9 AbstractTwo types of nanofiltration membranes had been used to study the influence of cross flow velocity on the membrane filtration ofdenitrification effluent (NF270 and NF90). Filtration had been conducted at constant transmembrane pressure of 5 bar andvariable cross flow velocity (0.03, 0.06, 0.15 and 0.39 ms-1). The obtained normal flux was 0.47, 0.58, 0.59 and 0.77for NF270membranes and 0.35, 0.38, 0.41 and 0.39 for NF90 membranes, the increase in cross flow velocity had enhanced fluxperfor... Autori: Abdel Halim Fuqaha ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26523
SIMPLE ECO-FRIENDLY -GALACTOSIDASE IMMOBILIZATION ON FUNCTIONALIZED MAGNETIC PARTICLES FOR LACTOSE HYDROLYSIS
Environmental Engineering and Management Journal › Vol. 14 › Nr. 3 Abstract
β-galactosidase from Aspergillus oryzae was strongly immobilized on magnetic particles functionalized with amino groups. By
simple incubation without any activating agents, electrostatic interactions between amino groups and enzymes allowed obtaining
a strong linkage. The immobilization efficiency was studied with the quantification of amino groups of the particles and of
immobilized β-galactosidase. Kinetic parameters, especially the maximal velocity Vmax and the affinity... Autori: Kalim Belhacene ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26682
RESONANT TECHNIQUES AS NON-DESTRUCTIVE TECHNIQUES (NDT) APPLIED TO COMPOSITE MATERIALS: CASE STUDY ON LOW VELOCITY IMPACTS DETECTION
Environmental Engineering and Management Journal › Vol. 14 › Nr. 5 Abstract
Impact damage is considered the primary cause of in-service delamination in composite materials and promotes significant
reduction in residual strength. Non-destructive techniques (NDT) include several methods able to detect the shape and the size of
the interior damages without destruction of the structure or component, which is economically advantageous. The aim of this
paper is to evaluate the properties after low velocity impacts using an experimental-numerical procedure based o... Autori: Ana Martins Amaro ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26726
STUDY OF PRESSURE DROP IN FIXED, FLUIDIZED AND SPOUTED BED OF SEVERAL ADSORBENT MATERIALS
Environmental Engineering and Management Journal › Vol. 14 › Nr. 10 Abstract
An experimental study on the hydrodynamics of fixed, fluidized and spouted granular bed was performed. With this aim two
commercial adsorbent materials and a composite material obtained by impregnation with a hygroscopic inorganic salt were
employed. The fluid phase consisted in dry air. The obtained results highlight the influence of grain size, material density and
roughness over pressure drop and gas velocity. Increasing grain size leads to decreasing pressure drop and increasing... Autori: Ioan Solomon ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26854
STUDY OF THE ADSORPTION OF Cu2+, Cd2+ AND Pb2+ ON AMORPHOUS Al(OH)3 IN DRINKING WATER SUPPLY NETWORKS
Environmental Engineering and Management Journal › Vol. 14 › Nr. 12 Abstract
Trace metal elements commonly exist in drinking water. Excessive exposing on them may result in lots of health problems. This
paper mainly focuses on the accumulations of Cu2+, Cd2+, and Pb2+ in drinking water supply networks with amorphous Al(OH)3
formation. The effects of pH, water flow rate, and metal element contents were investigated at laboratory bench scale. It was
found that chemical adsorption mainly occurred at pH > 7.0. Suspended Al(OH)3 showed a strong adsorption capa... Autori: Wendong Wang ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26906
PRELIMINARY ANALYSIS OF STURGEONS SWIMMING CAPACITY ABOVE THE BOTTOM SILL BY NUMERICAL SIMULATION. BALA BRANCH CASE STUDY
Environmental Engineering and Management Journal › Vol. 15 › Nr. 5 The need of hydraulic structures for the improvement of the navigation conditions on the Danube, between Calarasi and Braila
(km 375 and km 175), led to the development of studies regarding the environmental impact. The studies were made by
correlating the dynamic implementation of hydraulic works with the results of the environmental monitoring, biotic and abiotic
factors. The hydraulic works designed to be built-up on the Bala branch, raised issues regarding sturgeons’migration in thi... Autori: Alina-Florina Nicolae ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27036
DIFFUSION CHARGING EFFECTS ON PM10 COLLECTION EFFICIENCY IN A WIRE-PIPE ESP UNDER MULTI-FIELD COUPLING
Environmental Engineering and Management Journal › Vol. 15 › Nr. 11 In this study, a mathematical model was introduced to calculate the collection efficiency of dust particles in a wire-pipe single-stage electrostatic precipitator (ESP). The aerodynamic diameters of these particles are less than 10 μm (PM10). The mathematical model, using combined Deutsch-Anderson Equation, considers coupling effects among gas flow field, electric field and particle field. A simplified 2-D ESP model was established using GAMBIT and a software application (FLUENT) was used to ... Autori: Jian-Ping Zhang ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27172
A STUDY ON THE DETERMINATION OF CUMULATIVE ABSOLUTE VELOCITY (CAV) THRESHOLD LEVELS FOR VRANCEA EARTHQUAKES
Environmental Engineering and Management Journal › Vol. 16 › Nr. 1 Natural disasters from earthquakes can cause considerable damages, with potentially severe effects to urban environment. Last strong Vrancea earthquake on March 4, 1977 (Mw=7.4, depth=95km); tens of thousands of buildings damaged, many people injured and dead. Strong earthquakes in the Vrancea zone occur between 60-200 km depth within an almost vertical column. Bucharest Earthquake Early Warning (EEW) system detects earthquakes with a seismic network in the epicentral Vrancea region and issue a ... Autori: Hakan Alcik ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27235
QUANTIFICATION OF EFFECTS PRODUCED BY THE EXTRACTION OF MINERAL AGGREGATES TOWARDS WATER BODIES
Environmental Engineering and Management Journal › Vol. 16 › Nr. 4 This paper presents the research performed in view of emphasizing the effects of mineral aggregates extraction on the geomorphological and hydraulic features of Moldova body of water. The effect on the geomorphological features was assessed by overlapping the cross profiles (22 profiles) and long profiles (2 profiles) from the entire area studied. These profiles were obtained by topographical measurements on the starting date (July 2013) and on the research end date, respectively (March 2015). T... Autori: Paula Cojocaru ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27335
PREVENTION OF ACCIDENTAL POLLUTION WITH COMBUSTION GASES AFTER THE OCCURRENCE OF EXPLOSIONS
Environmental Engineering and Management Journal › Vol. 16 › Nr. 6 This paper aims to study the behavior of air-gas explosion systems, in terms of propagation speed of pressure wave and flame front, based on experimental measurements in a shock tube, in order to prevent accidental pollution with the combustion gases. The characteristic parameters of the explosion process determined using the shock tube, the velocity of propagation of the flame
front, the speed of propagation of the wave of pressure, explosion pressure at various distances from the source of in... Autori: Emilian Ghicioi ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27355
CHEMICAL, MECHANICAL AND THERMAL PROPERTIES OF MORTAR COMPOSITES CONTAINING WASTE PET
Environmental Engineering and Management Journal › Vol. 16 › Nr. 7 The main objective of this study was to investigate the potential utilization of polyethylene terephthalate PET waste in cementitious matrix, as substituent to cement, to develop lightweight construction materials and for preventing chemical attacks or repairing various reinforced concrete structures. Composites containing different amounts of PET particles, as partial replacement to cement by weight, were characterized by destructive and non-destructive testing. So, the thermal conductivity, ul... Autori: Ahmed Soufiane Benosman ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27381
LONG-TERM IMPACTS OF GROUND SKIDDING ON STANDING TREES: ASSESSMENT OF DECAY USING STRESS WAVES
Environmental Engineering and Management Journal › Vol. 16 › Nr. 10 Timber harvesting and log extraction with conventional ground-based skidding systems in steep, mountainous terrain often results in severe damage to residual stands and forest sites. In this study, the impact of rubber-tired skidders on standing trees along sides of the trails was investigated 5 to 20 years post-harvest in terms of frequency and development of decay at the points of wounding. The study was located in the Hyrcanian mountainous forests of Iran. All standing beech trees (healthy or... Autori: Davoud Kartoolinejad ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27457
NUMERICAL SIMULATION OF INTERNAL MICROCLIMATE INSIDE A LIVESTOCK BUILDING
Environmental Engineering and Management Journal › Vol. 16 › Nr. 11 In the current work, a numerical model for the prediction of temperature, air velocity, relative humidity and ammonia distribution released by sheep and goats manure inside a naturally ventilated livestock building is presented. Given that noteworthy amount of gaseous pollutants are emitted by the agricultural and animal husbandry activities, the study of the indoor microclimate is essential to be investigated for the healthy growth of the breeding livestock. The developed numerical model is sat... Autori: Catherine Baxevanou ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27482
GAS HOLD UP IN THE CULTIVATION OF A PETROLEUM-DEGRADING BACTERIAL CONSORTIUM
Environmental Engineering and Management Journal › Vol. 17 › Nr. 5 The hydrodynamic behavior of bubble column bioreactors (BCB) is strongly dependent on the bubbly flow regime. Therefore, the influence of superficial gas velocity (Ug) and Sauter mean diameter (d32) on gas hold up (εg) was evaluated for the cultivation of a petroleum-degrading consortium. Hydrodynamic parameters were determined by photographic techniques. Also, the biomass cultivation was quantified by suspended solids formation (SS). Our findings indicated that the d32 increased at high... Autori: Olivia Tzintzun-Camacho ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27597
AN IMPROVED MODELING FOR PREDICTION OF PM2.5 COLLECTION EFFICIENCY IN ELECTROSTATIC PRECIPITATORS
Environmental Engineering and Management Journal › Vol. 17 › Nr. 3 In this work, PM2.5 removal mechanism was explored to investigate PM2.5 collection efficiency under the influences of applied
magnetic field and diffusion charging (the main charging mode for submicron particle). The proposed electrostatic precipitators
(ESPs) mathematical model considered three-field interaction between fluid field, electromagnetic field and particle dynamic field.
CFD software FLUENT was used to generate the simplified solid structure of the ESP. In numerical calculation, t... Autori: Jian-Ping Zhang ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27667
CHARACTERISTICS OF SOILS IMPROVED WITH POLYETHYLENE TEREPHTHALATE WASTES
Environmental Engineering and Management Journal › Vol. 18 › Nr. 2 In this study we investigated the possibilities of using recyclable fine and coarse grain waste obtained by grinding Polyethylene
Terephthalate (PET) containers, as light filling materials for different applications (clay dams, highway embankments, and backfills
behind retaining structures. Various geotechnical tests were performed on clayey soil and soil-PET mixtures using recycled fine
and coarse granules of Polyethylene Terephthalate bottles. The results indicated that the use of the recyc... Autori: Osman Gunaydin ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27920
CONTINUOUS INVASIVE MONITORING TECHNOLOGY FOR DETERMINATION OF AIR VELOCITY AT THE LEVEL OF MAIN VENTILATION STATION
Environmental Engineering and Management Journal › Vol. 18 › Nr. 4 Proper functioning of the main ventilation station depends on the mining network’s degree of ventilation. Also, knowledge of
changes in instantaneous aerodynamic parameters offers the possibility of taking operational measures necessary to maintain
optimal health and safety in the underground. The objective of the present paper is to identify a new method of monitoring the
aerodynamic parameters at the main ventilation station.
... Autori: Emeric Chiuzan ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27949
MODELLING THE PISTON EFFECT IN SUBWAY TUNNELS USING FIRE DYNAMICS SIMULATOR
Environmental Engineering and Management Journal › Vol. 18 › Nr. 4 The influence of the piston effect in subway tunnels depends on a train speed, the geometry of a tunnel and a train, the types of air
flow caused by mechanical ventilation and other variable characteristics. Tables and graphs of changes in air flows generated by
the effect of the piston are presented depending on the speed of a train and the degree of fill rate of a tunnel. It is noted that the
piston effect is characterized by two phases. At the first stage, the piston effect and the process... Autori: Omar Lanchava ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27959
EFFECTS OF ENVIRONMENTAL FACTORS ON THE BIOMASS OF BENTHIC DIATOM IN RIVERS
Environmental Engineering and Management Journal › Vol. 18 › Nr. 5 This paper aims to disclose the quantitative relationship between benthic diatom biomass in natural rivers and environmental factors.
For this purpose, the author selected seven natural rivers in the basin of Minjiang River as the objects. First, the samples of benthic
diatoms and the environmental factors were collected from 14 different sampling sites of five rivers and the diatom density and
Chlorophyll a (Chl a) content were selected to characterize the diatom biomass. Then, the number of... Autori: Baichuan Zhang ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28001
PROPAGATION CHARACTERISTICS AND ENVIRONMENTAL IMPACT OF COAL DUST EXPLOSION
Environmental Engineering and Management Journal › Vol. 18 › Nr. 9 Dust explosions are one of the main causes of mining disasters. To avoid them, it is important to understand how they are propagated. In the study reported here, computational fluid dynamics software was used to model a 3D diagonal pipe network then simulated a dust explosion at its inlet to examine its propagation characteristics. The initial conditions, boundary conditions and parameter settings were detailed description in the simulation to analyze possible propagation characteristics, assess... Autori: Baichao Song ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28067
CORRELATION BETWEEN AERATION AND ERGOSTEROL PRODUCTION BY YEASTS
Environmental Engineering and Management Journal › Vol. 18 › Nr. 12 The present study represents an extension of ergosterol production by Saccharomyces cerevisiae fermentation processes using oxygen-vector by establishing the influence of the analyzed main factors, such as aeration efficiency and hydrocarbon concentration. The study has been developed for batch and fed-batch fermentation systems and has been focused on the variation of ergosterol content inside the yeast cells during the fermentation cycle in correlation with hydrocarbon volumetric fraction, COV... Autori: Corina Ciobanu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28130
TURBULENT FLOW CHARACTERISTICS IN THE ERODED REGION OF THE SIDE-WALL BANK
Environmental Engineering and Management Journal › Vol. 19 › Nr. 8 An experimental inquest was performed to quantify the turbulent flow characteristics near the eroded region of an artificial sidewall bank at three different flow depths, and a comparison study is made between before and after erosion for two Reynolds numbers. Instantaneous flow velocities were taken with an acoustic Doppler velocimeter (ADV) at near bank of the vertical side wall. The mean flows and other turbulence quantities such as Reynolds shear stress, turbulent intensities, and turbulent ... Autori: Krishnendu Barman ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28264
DEVELOPMENT AND IMPLEMENTATION OF A WATER SAFETY PLAN FOR THE DRINKING WATER SUPPLY SYSTEM OF FLORENCE, ITALY
Environmental Engineering and Management Journal › Vol. 19 › Nr. 10 The adoption of the Water Safety Plan (WSP) approach, as recommended by the World Health Organization, represents the most effective means to guarantee public health protection and improve drinking water safety. WSP is a risk assessment and management
approach applied to all phases of the water supply chain. This study presents the development and implementation of the WSP for the municipality of Florence. The Florence drinking water supply system (DWSS) has two drinking water treatment plants ... Autori: Roberta Muoio ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28303 |