The residual waste has a high concentration of recoverable elements, which can be either recycled or recovered into energy in accordance with the waste hierarchy. One option is the implementation of mechanical biological treatment of waste, which has showed a steady progress in the recent two years in Hungary.
This paper analysis the relevant factors, which should be considered during the technology planning. The multi criteria analysis involves the economical environmental and external considerations into the technology assessment. Based on the results, the technology plan should be revised and adjusted.
For open channels significant pollution sources during the intensive precipitations are outflows from storm-water overflows on the sewer network. When combined with low discharges in rivers, the water released from overflows can cause high concentration of pollution in receiving open channels. In this paper, the results of computer modeling of the impact of storm-water overflows on the stream water quality in three municipalities in Czech Republic are shown. The local river networks are the main receivers in the cities where storm-water overflows are led in. The results serve as a base for the proposals on the measures, improvements and structural modifications.
Authors:Brigitta Török, Adél Len, and Zoltán Orbán
This paper presents a nonstandard experimental procedure for detection of the presence of salts in building materials. The proposed tests helped modeling the deterioration of specific historical building materials caused by salts. The specimens were subject to visual survey and scanning electron microscope analyses, after submerging them in salt solutions. The results showed the damage of brick, cement based mortar and lime based mortar, caused by various concentrations of sulphate and chloride solutions. By this method various types of salt crystals could be identified. In cement and lime based mortars larger extents of salt deposits were found. A relevant difference between the control samples and the salt treated samples was observed.
The abandoned Smolnik mine is regarded as an environmental loading in the Central Europe region, where acid mine drainage (AMD) is generated and discharged from abandoned mine and contaminates the Smolnik creek catchments. The whole mine complex produces large amounts of AMD with the pH 3–4 that contain high metal concentrations, fluctuating depending on rainfall intensity.The main aim of this work is to compare and to interpret the method of adsorption for the heavy metals (Cu, Fe, Al, Mn and Zn) removal from AMD out-flowing from the shaft Pech of the deposit Smolnik (Slovak Republic).
Pollution of the natural environment by heavy metals is a universal problem because these metals are indestructible and most of them have toxic effects on living organisms, when permissible concentration levels are exceeded. The degree of contamination in the sediments of the Smolnik creek, for the metals Ca, Mg, Fe, Mn, Al, Cu, Zn, As, Cd and Pb, has been evaluated using Enrichment factor (EF), Pollution load index (PLI) and Geo-accumulation index (Igeo). The sediments have been found to be contaminated with Pb, Cu and As which has been attributed mainly acid mine drainage from abandoned shaft Pech (the mine Smolnik) since no major industrial establishments are present in the area.
Authors:Adriana Eštoková, Jozef Oravec, and Martina Kovalčíková
The paper presents the results of leachability testing of selected heavy metals from the concrete composites of various compositions in order to assess the degree of a contamination risk of the environment. Tested concrete samples contained various amounts of special ingredients based on the blast furnace slag (65%, 75%, 85% and 95% of Portland cement replacement). Leaching tests have been performed by using distilled water. The concentrations of chromium and barium ions in the leachates were measured after period of 30 and 240 days. Changes in pH and conductivity values in leachates have been also observed.
Applying several hydrocolloids in ascending concentrations (0.1, 0.5 and 1% w/w flour basis) to bread making procedure was considered. Effect of hydrocolloids [guar, xanthan gum, carboxylmethylcellulose (CMC), and hydroxypropylmethylcellulose (HPMC)] as bread improver on Barbari (Iranian bread) was analysed in terms of microstructure. Image analysis parameters, hardness, and microstructure of fresh bread were analysed. The results confirmed the ability of hydrocolloids for improving fresh bread quality. Among all used hydrocolloids, HPMC and CMC produced the softest texture, smoothest and continuous structure, and improved overall the bread quality.
Authors:Endre Salamon, Zoltan Goda, and Tamás Berek
Unsuitable feed water quality causes fouling and serious decrease in membrane permeability during the operation of reverse osmosis filters, which leads to costly operation and low contaminant removal efficiency. The purpose of the experiment was to create a detailed, yet simple calculation scheme, suitable for higher education and everyday pilot experiments. The obtained formulas were calibrated against measured results, while investigating the fouling of the membranes at different iron concentrations. Pressure losses on a reverse osmosis equipment with a permeate capacity of 100 L/h were investigated for almost a year. Changes in permeability and cleaning methods were investigated with different feed water qualities.
Authors:N. Topic Popovic, A. Benussi Skukan, P. Dzidara, I. Strunjak-Perovic, S. Kepec, J. Barisic, and R. Coz-Rakovac
Listeria monocytogenes is a bacterium widespread in the environment, which has a capacity to survive and grow under various conditions. The bacterial growth results from interactions when subjected to various temperatures, pH levels, and NaCl concentrations were examined by measurements and predictive modelling. Good correlation across the range of growth conditions was shown among observed and predicted growth values, having similar trends and minimal deflections for pH levels 5.0 and 6.0. The growth condition in the 8% NaCl concentration (pH 7.0, temperature 4 °C) resulted with a growth curve of 1 log interval greater than the fitted curve for all the measurements. In all of the cases, there were consistent increases in the rates and decreases in the lag time when the growth temperature increased. Higher incubation temperatures provided higher growth rates as 30 °C and 35 °C yielded double increase of the fitted rate. Fitted and measured growth rates for salinity conditions were significantly different (P<0.05). Comparison of doubling times showed good compatibility, particularly at lower temperatures. Critical use of a model is suggested, although it may enable microbiologists to limit the need of challenge tests and to make rapid and realistic prediction of the growth of L. monocytogenes under conditions relevant to a range of aquatic and other products examined.
Authors:E. Takács, A. Nagy, É. Gelencsér, and A. Székács
Reliable determination of microbial or transgenic Cry toxins is an essential issue in food and feed analyses, and enzyme-linked immunosorbent assays (ELISAs) are the method of choice for quantifying these toxins currently in food and environmental analysis. Internal Quality Control (IQC) is an indispensable method to assess accuracy, precision, and reproducibility of analytical measurements. To assess the utility of the ELISA method, IQC was performed on EnviroLogix Cry1Ab/Cry1Ac QualiPlate ELISA with manufacturer supplied analytical standards. Applicability of negative and positive controls (C− and C+) was examined by Shewhart Control Charts for bias and Control Chart of the Range of Duplicates for precision. Linear regression (up to 5 ng ml−1 Cry1Ab concentration) of the commercial ELISA kit was compared to sigmoid calibration (up to 60 ng ml−1 Cry1Ab concentration). For immunoassay optimization process, possible matrix effects in different liquid and solid vertebrate tissues were examined by determination of the limit of detection values in these matrices.