Hidrogeohemijska ispitivanja kvaliteta podzemnih i površinskih voda u neogenim - kvartarnim sedimentima

Geochemical investigations in order to identify the mineral deposits, as well as the sources of water supply of rural settlements included in the area of Bela Crkva, between the Nera and the Karaš rivers, draining the Neogene and Quaternary sediments. During the prospecting, water samples were collected from surface water streams, springs, wells, drills, water reservoirs, as well as the samples of stream sediments and rocks. Hydrogeochemical investigations are of significance, where, in the water of Vrsac hills, elevated levels of radionuclides U, Ra and Rn, and other toxic elements were detected with values above maximum allowed concentrations for drinking water. The wells of rural households had increased levels of Fe and Mn, as well as the increased mineralization, conductivity, and nitrogen cycle. The concentration of heavy metals in water wells was increased in the most settlements around Bela Crkva, as well as in Češko Selo, Banatska Subotica, Kuštilj, Jablanka and Karaš river. From the water accumulations formed in the Quaternary sediments southwest from Bela Crkva, samples of water, mud, overbank sediments, and A-horizon were collected. The water samles were determined on: Na, K, Ca, Mg, Fe, Mn, Al, NH4, NO3, SO4, HCO3, Cl, F, Ep, Eh, pH value, mineralization, Pb, Cd, Co, Ni, Cr, Cu, Zn, H2S, O2, CO2, U, Ra, Rn, As, Hg, Br. In the solid samples, Au, Ag, Pb, Zn, and other elements, as well as the content of 238U, 232Th and 40K were determined. Test results are presented in tables, diagrams, and hydrogeochemical maps.Geološko-geohemijska istraživanja u cilju identifikacije ležišta mineralnih sirovina, kao i izvorišta za vodosnabdevanje ruralnih naselja obuhvatila su područje Bele Crkve, između reka Nere i Karaša, koje dreniraju sedimente Neogena i Kvartara. U toku prospekcije, prikupljeni su uzorci voda iz površinskih tokova, izvora, bunara, bušotina, vodenih akumulacija, potočnih sedimenata i uzorci stena. Značajna su hidrogeohemijska ispitivanja, u kojima su u vodama otkriveni povišeni sadržaji radionuklida U, Ra i Rn u području Vršačkih brda, kao i drugih toksičnih elemenata, čije su vrednosti iznad maksimalno dozvoljenih u vodi za piće. U bunarima seoskih domaćinstava povećani su sadržaji Fe, Mn, a povećani su i mineralizacija, provodljivost i azotni ciklus. Koncentracija teških metala u bunarskim vodama je povećana u većini naselja oko Bele Crkve kao i u naseljima Češko selo, Banatska Subotica, Kuštilj, Jablanka kao i reka Karaš. Od vodenih akumulacija nastalih u kvartarnim sedimentima JZ od Bele Crkve; prikupljeni su uzorci voda muljevite komponente s dna jezera, overbank sedimenata i A-horizonta. U uzorcima voda određivani su : Na, K, Ca, Mg, Fe, Mn, Al, NH4, NO3, SO4, HCO3, Cl, F, Ep, Eh, pH, mineralizacija, Pb, Cd, Co, Ni, Cr, Cu, Zn, H2S, O2, CO2, U, Ra, Rn, As, Hg, Br, u čvrstim uzorcima Au, Ag, Pb, Zn, U i dr. elementi, kao i sadržaji U, Th i 40K. Rezultati ispitivanja prikazani su: tabelama dijagramima i hidrogeohemijskim kartama

Removal of manganese and iron from groundwater in the presence of hydrogen sulfide and ammonia

Presence of iron and manganese in water not only affects the organoleptic properties of water, but also can cause a number of problems in drinking water treatments. Their removal in drinking water preparation processes becomes more complicated in the presence of hydrogen sulfide and ammonia in water. There are certain commercialized products at the market that are used for removal of manganese, iron and ammonia, but it is of crucial importance to establish an appropriate order of removal in the technological process during drinking water treatment. Through the various combinations of commercialized filtration media, the removal of iron, manganese, hydrogen sulfide and ammonia, was being examined and on the basis of obtained results their effectiveness was estimated. Research results have shown that hydrogen sulfide is pollutant that causes problems during the adsorption in removing manganes. Ammonia, which is bonded to hydrogen sulphide influences the volume of treated water when it comes to removing the iron and manganese. Decrease in the concentration of hydrogen sulfide at the entrance to Filtersorb FMH for four times, has led to an increase in the volume of treated water in the amount of two times, followed by the breakthrough point of concentration of manganese. For complete usage capacity of commercialized products for the removal of these pollutants, finding their mutual bond in compounds which are present in the water, is of the importance

Assessment of the Trophic Status by Monitoring of Reservoir’s Water Quality

Continuous long-term monitoring of aquatic systems is important for understanding their complete evolution in order to monitor changes in the trophic status and water quality. The continuous monitoring during a period of 20 years, by sampling once a month at two locations, the water quality of reservoir “Grlište”, which is used for the water supplying town Zaječar (Eastern Serbia), is observed and developmental stages in the life of the reservoir were determinated. It should be noted that the obtained results were used also in the purpose of finding a cause of cyanobacteria bloom, as a consequence of algal production. Limiting factors of algal production usually were nitrogen and phosphorus, however, in this study, obtained results of subtraction between trophic state index, calculated through total chlorophyll a (TSIChl-a) and trophic state index, calculated through total phosphorus (TSITP), indicated that limiting factor of algal production was light. On the basis of the concentrations of dissolved oxygen (DO), total phosphorus (TP) and chlorophyll a (Chl-a) in the surface and in the bottom, it was concluded that the reservoir passed through four development phases during the examined period. Results of long-term monitoring showed that in the first years after the formation of the reservoir, the highest trophicity was detected (hypereutrophic status), but later the reservoir mostly maintained eutrophic status