AbstractMicrobial flora is an indicator of the environmental potential of allowing the air-transmitting infections. The paper presents the determination of micro-flora from public indoor spaces and hospital wards in an urban zone. There were used the following sampling and insemination methods: harvesting by sedimentation (Koch method) and harvesting by aspiration, filtration methods, barbotage method, impact method, electro-precipitation method and biotest Hycon. Air micro-flora determinations ...
Autori: Capatina Camelia, Cristinel Racoceanu, Gheorghe Lazăr
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25139

AbstractHeavy metals can be transported by rivers which flow through areas with industrial pollution, both as metal in solution and metal adsorbed to suspended solids. They can settle in lakes and accumulate in the sediment, exhibiting significant effects on wildlife and humans if they enter into the food chain.In this work, heavy metals transport and sedimentation is simulated based on an analytical model proposed in literature, considering the material balance and complementary equations, unde...
Autori: Camelia Beţianu, Florina Ungureanu, Loredana Branza, Lucian Vasile Pavel, Maria Gavrilescu, Simona Pintilie
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25197

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

Abstract The paper presents the preliminary experimental results performed at laboratory scale set-up for different combined mechanochemical treatments of final effluents from a zootechnical farm from the central Moldavian region of Romania. Because of the high content of pollutants into wastewaters, the soil can be polluted and also the ground waters. To avoid this soil pollution episode, some combined mechano-chemical processes were studied and applied into a specific technological order as...
Autori: Carmen Zaharia, Mioara Surpăţeanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25434

Abstract In this work the method for the treatment of industrial waste waters effluents containing hexavalent chromium in three companies during process of treating metal surface with chromic acid is described. Industrial water polluted with hexavalent chromium is collected in separate sewage system. Polluted water is collected in precipitation tanks which are directly connected with neutralization reservoirs. The treatment process includes pre-neutralization by lime-milk, sedimentation, floc...
Autori: Igor Creţescu, Mirjana Cvijovic, Predrag Djurdjevic, Slavica Cvetkovi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25596

Abstract:The aim of this work is to obtain sintered porous membranes with graded structure for microfiltration by sedimentation andsintering of metallic powders. Our previous studies have demonstrated the possibility of obtaining sintered porous materials withgraded structure by sedimentation. In this paper, spherical nickel particles were used having a grain size in the 2-90 Âľm rangemeasured by the laser scattering particle size analyzer. The powders were sedimented into a sintering die in a s...
Autori: Gyorgy Thalmaier, Ioan Vida-Simiti, Nicolaie Jumate, Niculina Sechel, Valentin Moldovan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25775

Abstract An activated sludge from SBBR (sequencing biofilm batch reactor) reactor filled with Fe0  as filler had been acclimated to Fe(III)rich environment aiming at secure an enrichment culture of iron-reducing bacteria. The dissimilatory Fe(III) reduction ability and its efficiency on the effect of nitrogen and phosphorous removal by dosing different Fe(III) under anaerobic condition were investigated. The mechanism was also proposed based on the results derived from the experiment a...
Autori: Jie Li, Juanjuan Feng, Siyuan Zhai, Ya’e Wang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25943

AbstractSecondary aluminium production inherently generates significant amounts of slag of variate composition and including dangerous compounds. Consequently, a care treatment of the resulted slag is imperatively necessary for preventing the environment pollution and for recovering valuable materials even if present in low amounts. The aluminium recovering procedure is based on a chemical and hydrometallurgical slag treatment, leading to the technical grade aluminium sulphate (AS), possible to ...
Autori: Carmen Tociu, Cristina Maria, Elena Diacu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26295

AbstractAmmonia pollution occurs frequently in urban water networks, which threatens the safety of water supply systems. Zeolite can beused for the removal of ammonium in the pretreatment of raw water for its peculiar adsorptive property to ammonium, but a largeamount of sludge from this measure could be a significant pollution source. In this work, the dewatering performance ofprecipitated sludge from the pretreatment of micro-polluted raw water was studied. Batch experiments of the simulatedco...
Autori: Bairong Zhu, Hao Chen, Huaizheng Li, Zhenliang Liao
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26355

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

The direct measurement of the nutrients largely contributes to understand how the quality of the information, coming from the instruments, may improve the performances of the plants. The advanced knowledge acquired on the meaning of the signals gives new possibilities to control the biological processes and estimate the operational state of the plant, improving the quality of the effluent and keeping the operational costs as low as possible. Such information, furthermore, can be used to under...
Autori: Carmine Fiorentino
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27127

The efficient use of fresh water sources and proper modeling of the water quality can only be possible when flows in the dam reservoir are well defined. Therefore, in this study, a hydrodynamics model of an actual dam reservoir in three dimensions for simulating a real dam reservoir flows for summer season is created. The model is developed using nonlinear and unsteady continuity, momentum, energy and k-ε turbulence model equations. In order to include the Coriolis force effect on the...
Autori: Fatih Üneş
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27430

Simulation experiments were conducted to investigate the behaviour of ozonation by-products and the removal of organic matter in the treatment of the Pearl River raw water. The treatment processes include pre-ozonation, conventional treatment processes (coagulation/sedimentation and sand filtration), post-ozonation and granular activated carbon (GAC) filtration. Treatment efficiency of each unit process was evaluated by using several parameters such as permanganate index (CODMn), ultraviolet abs...
Autori: Yue Wu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27580

The influence of the active compound of Moringa oleifera Lam (MO) seeds was evaluated by different methods for the preparation of the natural coagulant in the treatment of surface water. Nine methods were analyzed, comprising samples of seed powder with different granulometry, aqueous and saline solutions, evaluated before and after oil extraction from MO seeds. Tests of coagulation/flocculation and sedimentation were accomplished using simple Jar Test. Natural coagulant dose of 50 mg.L-1 identi...
Autori: Karina Cardoso Valverde
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27588

Polycyclic aromatic hydrocarbons (PAHs) are very hazardous compounds. This investigation is the third in a series of three experiments carried out in conventional wastewater treatment plants with regard to PAHs. The first experiment regarded the analysis of PAHs in a municipal wastewater sewage system and in the wastewater treatment plant (WWTP) effluent, followed by a comparison between the observed removal efficiency and FATE model (US-EPA) predictions. The second experiment was carried out in...
Autori: Vincenzo Torretta
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27629

Dam construction in Cuba and their use for freshwater aquaculture development are explained. Some of the environmental impacts of Cuban freshwater reservoirs, particularly in fisheries, the salinization of coastal lands, and effects on marine fisheries, are reviewed and analyzed. Some argumentation and explanations given are in response to remarks on the impact of Cuban dams on species composition of reservoir fishery landings and on coastal marine fisheries. The main impacts of dams are on estu...
Autori: Luis Alvarez-Lajonchčre
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27653

Bare zero-valent iron nanoparticles (bare-ZVIN) have a great tendency to aggregate, which drops their reactivity with pollutants. To address this issue, polyvinylpyrrolidone stabilized-ZVIN (PVP-ZVIN) was synthesized and used for the removal of Cd2+ from aqueous solution in a batch system. The effects of operation conditions such as the pH of aqueous solution (2-8), reaction time (0-120), adsorbent concentration (1-6 g L-1) and the initial Cd2+ concentration (10-60 mg L-1) on the removal efficie...
Autori: Amirhosein Ramazanpour Esfahani
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27764

In this work, the examination of separation of gypsum from wastewater generated during the machining of casts and the method of waste gypsum management have been presented. This waste gypsum is produced in Ortolab Poland facilities. Gypsum casts are cut and ground in water-cooled circular saws. Wastewater, with over-normative content of suspension, 10000 mg L-1 and sulphates, 1600 mg L-1 is produced in the process. The analysis of water and wastewater management in Ortolab Poland facilities l...
Autori: Ewa Liwarska-Bizukojc
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27910

Drinking water treatment aims to avoid or minimize some risks to human health and to provide adequate water quality by removing physical, chemical and biological contaminants. However, treatment processes require increasing efforts in terms of technology, chemicals and energy inputs, which generate increased secondary environmental impacts and added water production costs. The objective of this study is to evaluate the drinking water treatment plant (DWTP) in Iasi City (Romania) by life cycle...
Autori: George Barjoveanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27922

The present paper is a multidisciplinary investigation of the indoor air quality inside the Multipurpose Hall of the University of Oradea, based both on specific monitoring and questionnaire-based survey to identify people’s perception in this regard. The monitoring, carried out during October-November 2016 when the heating did not work, was focused on: relative air temperature and humidity (Thermohygrometer data logger Klimalogg Pro), carbon dioxide (CO2) (Extech Instruments CO250 model a...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27981

A Computational Fluid Dynamics (ANSYS Fluent CFD) software was applied for the examination of a critical combined sewer section of Budapest (Hungary) sewer network. The critical part of the main branch is located at a combined sewer overflow (CSO) which is implying environmental risk for the receiving water body. The CFD simulations proved the anticipated disadvantageous hydrodynamic effects of the lateral inflow. A discrete phase model (DPM) was also applied to analyse the sediment transport...
Autori: Marcell Knolmar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28183

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