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Wyświetlanie 1-2 z 2
Tytuł:
Mobilność wybranych metali ciężkich w komunalnych osadach ściekowych
Mobility of Selected Heavy Metals in Municipal Sewage Sludge
Autorzy:
Wikarek-Paluch, E.
Rosik-Dulewska, C.
Karwaczyńska, U.
Powiązania:
https://bibliotekanauki.pl/articles/1818051.pdf
Data publikacji:
2016
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
metale ciężkie
komunalne osady ściekowe
sekwencyjna ekstrakcja chemiczna
heavy metals
municipal sewage sludge
sequential chemical extraction
Opis:
The research was aimed at determining the interaction of municipal sewage sludge with the environment in the aspect of its potential for land applications in agriculture, land reclamation and land adaptation to different uses. Sequential extraction of heavy metals according to Brümmer’s method was used in the study. A detailed interpretation of the data allowed to state that the highest content of copper was found in one of the most mobile bindings (fraction I). For other heavy metals only trace amounts were found in the bindings considered as the most mobile (fraction I-III) which proved less risk posed to the environment. The highest percentage share of heavy metals in the investigated sludge was determined in fractions IV to VII (i.e. in bindings rather unavailable to the ecosystem). It should be highlighted that three out of the seven determined metals were bound in the highest amounts with the organic matter (fraction IV): i.e. Zn 49.97%, Pb 66.58% , Mn 41.91%.; three with silicates (fraction VII): i.e.: Cu 40.60%, Ni 88.58%, Cr 34.33%; and only cadmium was found to be bound (30.29%) with crystalline iron oxides (fraction VI).
Źródło:
Rocznik Ochrona Środowiska; 2016, Tom 18, cz. 2; 181-192
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamika ekstrakcji Zn, Cu, Ni, Pb i Cd z przemysłowych i komunalnych osadów ściekowych przy zastosowaniu roztworów EDTA i kwasu cytrynowego
Dynamics of Zn, Cu, Ni, Pb and Cd Extraction from Industrial and Municipal Sewage Sludge Using EDTA and Citric Acid Solutions
Autorzy:
Karwowska, B.
Powiązania:
https://bibliotekanauki.pl/articles/1818058.pdf
Data publikacji:
2016
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
osady ściekowe
metale ciężkie
ekstrakcja chemiczna
EDTA
kwas cytrynowy
sewage sludge
heavy metals
chemical extraction
citric acid
Opis:
Sewage sludge generated in wastewater treatment plants accumulates varied contaminations of inorganic as well as organic character. Among them, heavy metals constitute a group of chemical substances which are highly dangerous for natural environment, because of the possibility of their mobilization and migration in environment as a result of changes in surrounding system. Moreover, they are pollutants toxic for humans, non-biodegradable and accumulate in living organisms. In recent years, there has been a great interest in the removal of heavy metals from sewage sludge with different chemical compounds solution and especially metal chelating agents. The goal of this work was to determine the optimal time for extraction of selected metals (Zn, Cu, Cd, Ni, Pb) from contaminated industrial and municipal sewage sludge by using 0.1 M solutions of EDTA (disodium salt of ethylenediaminetetraacetic acid), as well as citric acid. The analyzed wastewater sludge was collected from metallurgic industry treatment plant and from municipal wastewater treatment plant. In sewage sludge samples, the principal parameters were determined and after mineralization with mixture of concentrated mineral acids: HNO3 and HCl (1 : 3) the total content of analyzed heavy metals was detected using atomic absorption spectrophotometry. Chemical extraction of metals from sewage sludge 5 g samples was carried out with 50 c3 portions of 0.1M EDTA and citric acids solution for different periods of time, i.e. from 0.5 to 24 hours. After given time of shaking, the liquids were decanted, filtered through a filter paper, and finally the extracts were analyzed for heavy metals content with AAS method. It was observed that both applied solutions effectively washed metals from studied sewage sludge samples. For the period of time from 0.5 up to 5.0 hours, the concentration of almost all metals increased linearly and in the 6th hour of extraction the process was limited and finally for the period of time from 8.0 up to 24 hours, the detected metal contents in extracts were practically the same. The analysis of dependences of metal concentration versus time of extraction yielded in the optimal time of process, what value was determined as equal to 6 hours. The efficiencies of the metals removal from the studied sewage sludge by mans of the analyzed solutions of extractants were compared. Copper and lead reached higher concentration in liquids after EDTA extraction. It indicated that EDTA solution was a more effective extractant for the afore-mentioned metals. The concentration of zinc was higher in citric acid solution and citric acid was determined as more effective compound for zinc removal. For nickel and cadmium, the concentrations of metals were similar in both type of washing solution, which indicated that the efficiencies of both solutions were comparable.
Źródło:
Rocznik Ochrona Środowiska; 2016, Tom 18, cz. 2; 681-694
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

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