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Inglezakis V.J.,Science European Focus Consulting srl | Elaiopoulos K.,National Technical University of Athens | Aggelatouc V.,Entrance | Zorpas A.A.,University of Cyprus
Desalination and Water Treatment | Year: 2012

Iron and manganese are found naturally in several soil and rock minerals while in the same time they are used as raw material in steel manufacture and products. Both metals can reach ground water reserves easily by rain or other means and while surface water does not usually contain high concentrations of iron or manganese because the oxygen-rich water enables both minerals to settle out as sediments, in anaerobic conditions, like in ground water deposits, iron and manganese are reduced to their soluble oxidation states Fe2+ and Mn2+. The problem of groundwater contaminated with these metals has become evident the last decades and several methods have been tested in the related literature. Ion exchange and adsorption are inexpensive and simple methods, especially when natural minerals are used, as zeolites and clays, however, the relevant studies of simultaneous removal of Fe and Mn from natural samples in the literature are few. In the present study natural clinoptilolite (zeolite) and vermiculite (clay) are utilized for simultaneous removal of Fe and Mn from underground water samples in open flow and closed loop fixed bed systems. A closed loop fixed bed system is a fixed bed with recycling of liquid phase and thus, is a type of batch process. Vermiculite exhibited higher removal levels than clinoptilolite for both Fe and Mn. For both materials Fe removal is higher than Mn. In the closed loop fixed bed system after 24 h of treatment and 2 g/100 ml solid to liquid ratio, Fe and Mn removal levels reach 100% and 75% for vermiculite and 82% and 30% for clinoptilolite, respectively. Pretreatment of groundwater by precipitation increases removal of Fe and the system could reach 100% removal for clinoptilolite as well. Finally, results show that under the same operational conditions, closed loop fixed bed system is more promising for groundwater treatment than batch system. © 2012 Desalination Publications.

Inglezakis V.J.,Science European Focus Consulting srl | Zorpas A.A.,University of Cyprus
Desalination and Water Treatment | Year: 2012

The heat of adsorption, the adsorption energy and the activation energy are of the most important and frequently calculated parameters in adsorption and ion exchange systems. However, in many occasions these parameters are not clearly defined, appropriate calculated or analyzed in the related literature. A characteristic example is the use of different limits used in order to identify a process as physisorption, chemisorption or ion exchange. The present paper aims at clarifying the nature of these parameters and their interrelationship in theoretical basis and to present the paradigm of ion exchange systems involving zeolites and cations as a case study. All basic theoretical issues are presented, analyzed and discussed with the support of a large number of experimental data in order to draw secure conclusions on several critical issues. In total 46 activation energy, 32 adsorption energy and 34 heat of adsorption experimental values are collected and discussed. © 2012 Desalination Publications.

Cobzaru C.,Technical University Gheorghe Asachi | Inglezakis V.,Science European Focus Consulting srl
Environmental Engineering and Management Journal | Year: 2012

The sorption capacity of the native Romanian clinoptilolite and analcime employed for removing Cu2+ ions from wastewater was investigated under various conditions of temperature, time and solution concentration. These parameters are necessary and sufficient for developing a mathematical model of the sorption process. The corresponding mathematical models show common characteristics due to the good arrangement of the experimental points on the response surfaces and correlation coefficients close to unity. Differences appear with respect to the shape of the response surface and model equations.

Hamidpour M.,Vali e Asr University of Rafsanjan | Afyuni M.,Isfahan University of Technology | Khadivi E.,Isfahan University of Technology | Zorpas A.,Sustainable Development Technology | Inglezakis V.,Science European Focus Consulting srl
International Agrophysics | Year: 2012

A 3-year field study was conducted to assess effects of composted municipal waste on some properties, distribution of Zn, Cu in a calcareous soil and uptake of these metals by wheat. The treatments were 0, 25, 50 and 100 Mg ha-1 of municipal solidwastewhichwas applied in three consecutive years. The application of composted municipal waste increased the saturated hydraulic conductivity, the aggregate stability, the organic carbon content and electrical conductivity, whereas it slightly decreased the soil pH and bulk density. A significant increase in the concentration of Zn and Cu were observed with increasing number and rate of compost application. The distribution of Zn and Cu between the different fractions in untreated and treated soils showed that the majority of Zn and Cu were in the residual form. Finally, the levels of Zn and Cu were higher in grains of wheat grown in composttreated plots compared to that grown in the control plots. © 2012 Institute of Agrophysics. Copyright © 2012 Institute of Agrophysics, Polish Academy of Sciences.

Inglezakis V.J.,Science European Focus Consulting srl | Zorpas A.A.,Science European Focus Consulting srl | Venetis C.,Euroconsultants SA | Loizidou M.,National Technical University of Athens | And 4 more authors.
Fresenius Environmental Bulletin | Year: 2012

This paper presents the results of the analysis of the relation between waste management and economic situation for the years 2000-2013 in Romania, Bulgaria, Slovenia and Greece. In particular, the interest of the present study focuses on the "decoupling principle" which falls within the EU policies. The population growth, the gross domestic product and the municipal solid waste generation constitute the basic indicators used. These indicators are integrated into one, the municipal waste intension (MWI) indicator, allowing for easy comparison between the countries and simplifying data analysis. In general terms, it can be stated that there is a decoupling of waste generation and economic growth in all countries as well as in EU-27 on average. Greece seems to follow the EU-27 average, Slovenia, Romania and Bulgaria show similar patterns with Bulgaria to show a sharper and larger decrease of the MWI indicator. © by PSP.

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