Environmental Engineering

In a previous study, treatment sludge obtained from a chemical industry, which contained potentially toxic heavy metals and organics, was characterized and solidified by solidification/stabilization (S/S). In this study, however, the prediction of leaching behavior of the sludge by linear regression method and neural networks (NNs) was discussed. NN analysis was used to construct models of leaching behavior as a function of mix composition (waste/binder ratio, W/B) using existing data from the previous study of cement-based S/S. The differences in leaching rate of each metal were also considered. The hazard characteristics of the waste were determined as defined in both Turkish and US EPA regulations, by means of Extraction Procedure Toxicity Test (EPTox) and DIN 38414-S4 Test. S/S studies were conducted using Portland cement to solidify the sludge containing high amount of Cr, Cu, Hg, Ni, Pb, and Zn. The W/B ratios of 36 specimens were kept between 0/100 and 40/100. The specimens were cured at room temperature for 7, 28, and 90 days. The heavy metal content of the extracts of each specimen was detected usually less than standard concentrations in EPTox and DIN 38414-S4 leaching procedures. By the use of NN, leaching behavior of the solidified wastes can be predicted and, therefore, optimum S/S technologies can be achieved.

The bay of Izmir, which is the biggest harbor on the Aegean Sea, is of upmost economical importance for Izmir, the third largest city in Turkey. Most of the studies carried out focused on the effects of intensive industrial activity and agricultural production on the bay pollution within the region. These studies, most of the time, are limited to monitoring the level of pollution. However, it is believed that these studies should be supported with models and statistical analysis techniques, as the models, especially the prediction ones, provide an important approach to assessing risk and assessment. In this study, neural network analysis was used to construct prediction models for nanoplankton population change with nutrients and other environmentally important parameters. The results indicated that, using data over a 52 week period, it is possible to predict nanoplankton population dynamics and dissolved oxygen change for the future.

Sewage treatment works are one of the major sources that cause atmospheric odour pollution. The increase in the number of complaints about odour nuisance is due to the increase in environmental concerns. Unfortunately, the legislation on odour nuisance from sewage treatment works is very limited. In order to determine suitable thresholds on which to base legal standards, reliable and efficient odour measurement methods need to be defined. A chemical sensor array was developed for the purpose of measuring wastewater odour. This paper describes the development of the chemical sensor system which is specifically tuned to odours of wastewater origin and which can give an electronic measure of the wastewater odours. Odour emissions from a wastewater treatment facility were detected by using a quartz crystal microbalance (QCM) sensor array. The array consists of nine sensor elements, which were coated with different materials. In this paper, the usage of these novel instruments in the water industry was shown.

Sewage treatment works are one of the major sources that cause atmospheric odour pollution. Due to the increase in environmental concerns, there is a growing number of complaints on odour nuisance. In order to determine the boundaries of legal standards, reliable and efficient odour measurement methods need to be defined. An electronic nose was used for the purpose of characterising sewage odours. Samples collected at different locations of a wastewater treatment plant were classified using an Artificial Neural ...

Each stage of the sewage treatment process emits odor causing compounds and these compounds may vary from one location in a sewage treatment works to another. In order to determine the boundaries of legal standards, reliable and efficient odor measurement methods need to be defined. An electronic NOSE equipped with 12 different polypyrrole sensors is used for the purpose of characterizing sewage odors. Samples collected at different locations of a WWTP were classified using a fuzzy clustering technique and a neural network trained with a back-propagation algorithm.

... Corresponding author: Berna Yavuz, Department ... of sulphide to elemental sulphur and af-terward to sulphate are carried out by phototrophic (Kim et al., 1990, 1992, 1993; Henshaw et al., 1998; Henshaw and Zhu, 2001; Hurse and Keller, 2004a, 2004b) and col-orless sulphur ...

ABSTRACT The presented project initiative CLIMB (‘Climate Induced Changes on the Hydrology of Mediterranean Basins – Reducing Uncertainty and Quantifying Risk’) has recently signed a Grant Agreement in EC’s 7th Framework Program (FP7-ENV.2009.1.1.5.2). In its 4-year design, starting from January 2010, the collaborative project for specific cooperation actions (SICA) dedicated to international partner countries shall analyze ongoing and future climate-induced changes in hydrological budgets and extremes across the Mediterranean and neighboring regions.This is undertaken in study sites located in Sardinia, Northern Italy, Southern France, Tunisia, Turkey, Egypt and the Palestinian-administered area Gaza. The work plan is targeted to selected river or aquifer catchments, where theconsortium will employ a combination of novel field monitoring and remote sensing concepts, data assimilation, integrated hydrologic modeling and socioeconomic factor analyses to reduce existing uncertainties in climate change impact analysis. Advanced climate scenario analysis will be employed and available ensembles of regional climate model simulations will be downscaled. This process will provide the drivers for an ensemble of hydro(-geo)logical models with different degrees of complexity in terms of process description and level of integration. The results of hydrological modeling and socio-economic factor analysis will enable the development of a GIS-based Vulnerability and Risk Assessment Tool. This tool will serve as a platform for the dissemination of project results, including communication with and planning for local and regional stakeholders. An important output of the research in the individual study sites will be the development of a set of recommendations for an improved monitoring and modeling strategy for climate change impact assessment. CLIMB is forming a cluster of independent projects with WASSERMed from the Environment and CLICO from Socio-Economic Sciences and Humanities Call of FP7 in 2009 (see Fig. 2). The intention of this clustering is to foster scientific synergy and cooperation between the partner projects to achieve improvements in policy outreach on different spatial scales.

... 2. Materials and methods The experimental set up used in this study is depicted in Fig. ... The treatment system was supplied with 50 L of aquaculture wastewater everyday from the barra ... 1. Schematic of the experimental setup (A = airflow meter, P = pump, PG = pressure gauge, V ...

... similar to fulvic acid were found to increase with age in landfill leachate [8]. A ... of removing capability of recalcitrant organic compounds and heavy metals from leachate [12 ... use of MF and UF membranes, dissolved organic and inorganic impurities could not be effectively treated. ...

Many countries in the Mediterranean basin are facing water shortage issues. Since water is becoming a rare resource, grey water and domestic wastewater reuse arises as a sustainable solution to reduce the overall water demand. In this study, a compact household reverse osmosis unit was used in order to determine the feasibility of pre-treated grey water and domestic wastewater reuse.

ABSTRACT During biosorption, removal is ensured by several mechanisms that occurred between living or nonliving microorganisms and transporting metal ions. In this study, the kinetics, equilibrium, and thermodynamics of the biosorption of Cu2+ onto dried activated sludge and Spirulina platensis from aqueous solution were investigated at different experimental conditions. The biosorption characteristics were investigated with respect to some of the significant parameters including the effect of pH, biosorbent dosage, and temperature. The Langmuir, Freundlich, and Temkin equilibrium adsorption models were studied. Results showed that Langmuir isotherm model fitted well the experimental data followed by the other isotherm models used. In order to determine the mechanism of the biosorption, kinetic models were applied. The results of the kinetic studies indicated that the biosorption processes fitted the pseudo-second-order model. The thermodynamic parameters were also calculated, and the values indicated that the biosorption process was spontaneous, exothermic, and more ordered in nature.

A novel circulating jet loop bioreactor adapted for organic matter oxidation has been designed and constructed. In this study, the input was leachate samples collected from Kemerburgaz Odayeri waste landfill site located on the European side of Istanbul. Controlling the jet loop bioreactor to realize high rates of purification depends on maintaining the appropriate loadings and operating conditions. This requires collecting various system data to estimate the dynamics of the system satisfactorily with the aim of keeping certain parameters within the specified range. The differential transform method (DTM) based solution of the state equations reveals the current state of the process so that any deviation in the system parameters can be immediately detected and regulated accordingly. The respirometric method for kinetic parameter calculations for biodegradation has been used for some time. In many studies, the respirometer was designed separately, usually in bench-scale. However, when a separate respirometer is used, the scale effect and parameters that affect the hydrodynamic structure of the system should be taken into consideration. In this study, therefore, the jet loop reactor itself was used as a respirometer. Thus, the kinetic parameters found reflecting the characteristics of microorganisms used for biodegradation would be more realistic. If the main reactor, here the jet loop reactor, would be used as the respirometer, the kinetic parameter changes can easily be monitored in the long run. Using the bioreactor as a respirometer, the most important kinetic parameters, Ks, kd and micromax were found to be 11,000 mg L(-1), 0.019 day(-1), and 0.21 day(-1), respectively. The stoichiometric coefficient, Y, was found to be 0.28 gr gr(-1) for the present system.

A novel circulating jet-loop membrane bioreactor adapted to high organic matter oxidation has been designed and constructed. Although jet loop bioreactors are still very new to wastewater treatment companies, their advantages over conventional treatment systems make these technologies beneficial, more affordable and consequently, commercially feasible. Since these reactors are capable of treating high organic loads, leachate, which has very complex