The aim of this paper is the investigation of natural materials that could be effectively used as a sorbent in the process of removing heavy metals from water. Interests are focused on the group to organic sorbents: natural wool fibres. The sorption experiments were conducted with lead, cadmium and zinc dissolved in distilled water, and then used as an example of heavy metal contaminated water and river water. Studies were performed in group sorption system. Possible use of natural fiber wool to remove heavy metals from water was determined by measurement of lead, cadmium and zinc before and after the sorption process. Analytical methods used for the determination of lead, cadmium and zinc in water by potentiometric stripping analysis. It was concluded that the sorption process mainly affect sorbent mass.

The possibility of applying the process solidification/stabilization for treatment of arsenic containing sludge, obtained after coagulation and flocculation treatment in the preparation of raw drinking water, using lime, cement and lime and cement in the mixture as stabilization agents was examined. Test results showed a high content of arsenic in the initial sample of sludge, above the allowable 41 mg As/kg by the USEPA prescribed for disposal of waste sludge. Performance of S/S process was investigated by two leaching tests, PCLP and DIN 38414-S4 test, which showed the highest efficiency of lime and cement mixture in the removal of arsenic by this procedure.

Groundwater from the middle Banat region (Serbia) which is used as a drinking water supply for Zrenjanin town contains a high amount of natural organic matter and a high content of arsenic. In this study a pilot-scale system was used to investigate the influence of different ozone doses (0.4-0.9 mg O3/mg DOC) during a pre-ozonation process on NOM removal by coagulation. Ferric chloride coagulant was chosen at a dose of 100 g/cubic meter, as a traditional coagulant which can also help in arsenic removal. The obtained results indicate that an ozone dose of 0.4 mg O3/mg DOC has the best influence on structural changes of NOM. The coagulation process with ferric chloride as coagulant had a significant influence on the arsenic content of the water, with the measured values in the water after coagulation in all three investigated treatment trains being below 10 microgram/l, which is the standard MCL in Serbian legislation.

Due to very high concentration of organic matter there is a great need for alternative solutions for drinking water disinfection in the world. Chlorine dioxide has been successfully used for almost 50 years for disinfection and later for taste removal, odor control, color reduction and oxidation of inorganic compounds such as iron and manganese. An advantage of using chlorine dioxide instead of chlorine is that it does not directly react with organic matter and form halogenated byproducts when it is used for disinfection. THMs, such as CHBr3, ChCl3 etc, are considered as most dangerous for people health. In this article we are to represent the results got from raw water disinfection treatment with chlorine dioxide.

Paper provides an overview of proposed methodology for planning and designing of system for collection, transport and treatment of road surface runoff in R. of Serbia. Methodology has objective to clearly define minimal scope and contents of required analyses, as well as to introduce into practice measures for protection of groundwater and soil from pollution, depending on sensitivity of the area on which road route is planned. paper also provides summary of required data and investigations needed for proper planning and designing.

Quality of groundwater from aquifers used for water supply in the town of Zrenjanin, does not meet the drinking water quality requirements. Among the basic problems are the high content of natural organic matter and arsenic, but also sodium and boron. This paper presents one of possible alternative of technological solutions for drinking water preparation in Zrenjanin. Research has lasted three years. The paper presents a only an outline of the drinking water preparation processes.

This study investigates removal efficiency of arsenic species from water on natural and modified sorbent materials. Selective removal of As(III) and As(V) from water was carried out with pure natural materials: bentonite, sepiolite, limonite, pyrolusite and zeolite. Materials most commonly used in water treatment, quartz sand and granular active carbon, were modified by iron coating in order to increase its sorption capacity. For the purpose of comparison, commercial material, granular ferry hydroxide (Everzit As), was investigated under the same conditions. The investigations were performed in batch experiments following the standard experimental methodology. Of all the tested natural materials zeolite exhibited significant sorption capacity: 100 microgram As(III, V)/g. Iron coating increased materials sorption capacity for at least 80%. Iron coated sand and iron coated activated carbon exhibited 340 and 430 microgram As(V)/g respectively.

This study investigates the possibilities of using Lagenaria vulgaris biomass as a biosorbent for removal of heavy metals from wastewater and natural water. The experiments were carried out with model solutions of Pb2+, Cd2+, and Zn2+, in batch system. The effects of contact time, temperature, initial metal concentration and adsorbent doses, on the adsorption of heavy metals have been studied. Results show that biosorbent based on Lagenaria vulgaris represent efficient and low-cost means for pretreatment of heavy metals contaminated waters.

In the project Quality of Drinking Water of Banja Luka City, during 2007 the colony of zoobentos around the water factory is followed. The composition of colony is different in both season and horizontal profile. The quality of water in litoral area of river is much worse, because polluted water from ambiental settlement and that is indicated by major number of Tubificidae. During monitoring of the states there was a change of qualitative and quantitative composition of colony, also and the change of individual domination of taxons.

This study was performed to investigate the efficiency of Fenton's process (FP) for removing natural organic matter, in particular the main disinfection by-products precursors. In order to determine the optimal reaction conditions of the process, the influence of pH, mixing speed and reaction time were investigated, as well as the influence of initial concentration and the molar ratio of Fe2+ and H2O2. The best results in terms of reducing the DOC content (by 82%) were achieved under pH 5, 30 rpm, reaction time of 15 min, Fe2+ concentration of 0.25 mM and a molar ratio of 1:10, and in terms of reducing trihalomethane and haloacetic acid precursors (by 98-99%) under a Fe2+ and H2O2 molar ratio of 1:20.