Wyniki wyszukiwania - Biblioteka Nauki

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Evaluation of pyritic tailings from a copper concentration plant for calcareous sodic soil reclamation

100%

Tozsin G. , Arol A. I. , Cayci G.

Physicochemical Problems of Mineral Processing

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2014

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tom Vol. 50, iss. 2

693--704

EN

This study was aimed to investigate the feasibility to use waste pyrite and sulphuric acid produced from waste pyrite for the reclamation of calcareous sodic soils. The final aim is to displace Na from an exchange complex and replace it with Ca, leading to a decrease in pH and exchangeable sodium percentage (ESP) and an improvement of soil structure. A fertility of the soil may also be enhanced by this technique since waste pyrite can be rich in several micronutrients. An additional advantage to this strategy is that waste pyrite is inexpensive and readily available in large quantities, by contrast to gypsum. In this study, column-leaching tests were carried out to evaluate a change in soil properties upon addition of gypsum and pyritic tailing amendments from a copper concentration plant. An availability of essential micronutrients for a plant growth (Fe, Cu, Zn and Mn) and hazardous potential of pyritic tailings in terms of heavy metal contamination were taken into account. Gypsum, powder waste pyrite and sulfuric acid produced from waste pyrite were applied to the soil with reference to the gypsum requirement (GR) of the soils. The results showed that application of waste pyrite with a dose of 44.74 megagrams per ha was superior to gypsum of 55.20 Mg/ha dose in terms of exchangeable sodium percentage (ESP) in 42 weeks. In addition, application of all the concentrations of sulfuric acid produced from waste pyrite also decreased the ESP values. The best values with sulfuric acid were obtained with a dose of 35.31 Mg/ha in 26 weeks. It was observed that the content of all micronutrients in the soil increased significantly (P<0.01) with waste pyrite and sulfuric acid applications. The levels of the micronutrients after treatments can be classified sufficient for the plant growth except for the iron level with the minimum dose of sulfuric acid application 17 Mg/ha. The heavy metal content in the soil after treatment with the pyritic tailings was found to be lower than the legal limit values. Thus, waste pyrite can be effectively used since rapid amelioration of calcareous sodic soils is possible with no deleterious heavy metal contamination.

2

Microbiology of acid waters ans ferruginous precipitates formation in the polish part of the Muskau Arch - preliminary raport

84%

Bożęcki P. , Rzepa G. , Ratajczak T.

Civil and Environmental Engineering Reports

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2010

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tom No. 4

13-18

EN

This work presents preliminary results of mineralogical, geochemical and microbiological investigations carried out in the Polish part of the Muskau Arch. As a result of sulphide oxidation in this abandoned mining area, highly acidified Fe-rich waters have been formed. Ferruginous precipitates composed mainly of schwertmannite, goethite, jarosite and gypsum accompany them. Both the water chemistry and the rate of the sediments formation vary significantly due to seasonal weather changes and microbiological activity.

PL

W pracy przedstawiono wstępne wyniki badań mineralogicznych, geochemicznych i mikrobiologicznych wykonywanych w polskiej części Łuku Mużakowa. W wyniku utleniania siarczków w tym opuszczonym obszarze górnictwa tworzą się wody bardzo zakwaszone oraz bogate w żelazo. Osady żelaziste składają się głównie z schwertmannitu, goethytu, jarosytu oraz gipsu. Zarówno chemia wody oraz tempo powstawania osadów różnią się znacząco ze względu na sezonowe warunki pogodowe i aktywność mikrobiologiczną.

3

Oxidation and dissolution of metal in circulating water - the fate of sulfide sulfur

84%

Nowak P. , Socha R. P.

Physicochemical Problems of Mineral Processing

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2006

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tom Vol. 40

134-148

EN

Dissolution of Zn, Pb, and sulfate ions in water from flotation lead-zinc ore tailings was investigated by passing water through columns filled with the waste. Conductivity, pH and concentration of selected ions in the effluent were measured and expressed as a function of exchange ratio of pore water (ER). Samples collected from the tailing after the experiments were investigated by X-ray photoelectron spectroscopy (XPS). Due to high concentration of carbonate minerals, which saturate the flowing water with hydrocarbonate ions, the concentration of both lead and zinc ions in the effluent is very low, below the standard for industrial waste water (except the very initial period). At the same time sulfide sulfur oxidizes partially to elemental sulfur, not to sulfates. For that reason the transfer of sulfates from the flotation wastes is rather limited.

PL

Badano rozpuszczalność jonów Zn i Pb oraz siarczanowych z odpadów flotacyjnych rud cynkowoołowiowych przepuszczając wodę przez kolumny wypełnione odpadami. Odcieki z kolumn badano oznaczając ich pH, przewodnictwo oraz stężenia wybranych jonów jako funkcję krotności wymiany wody porowej (ER) w odpadach. Z odpadów po doświadczeniu pobrano próbki, które badano metodą spektroskopii fotoelektronów generowanych promieniowaniem X (spektroskopia XPS). Stwierdzono, że dzięki dużej zawartości minerałów węglanowych, które nasycają przepływającą wodę jonami wodorowęglanowymi stężenia jonów cynku i ołowiu, poza początkowym okresem, są znacznie poniżej normy dla ścieków przemysłowych. Równocześnie siarczkowa siarka w znacznej części utlenia się do siarki pierwiastkowej a nie do siarczanów, co powoduje, że emisja siarczanów z odpadów jest stosunkowo niewielka.

4

The influence of bacterial reduction on concentrations of sulphates in deep aquifers in river drainage basin

67%

Kotowski T. , Burkowska A.

Polish Journal of Environmental Studies

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2011

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tom 20

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nr 2

EN

Our study attempts to determine the influence of bacterial reduction on sulphate concentrations in groundwaters. A buried valley in a southeastern section of the Gwda River drainage basin was selected for fieldwork near the towns of Wysoka and Bądecz. Deep aquifers in the area are known for their high sulphate concentrations that result from pyrite oxidation by the Thiobacillus denitrificans bacteria. Isotope compositions of SO₄²⁻ ions show ³⁴S enrichment at lower sulphate concentrations, which might indicate bacterial reduction processes. Theoretical curves of SO₄²⁻ isotope composition and ion concentration change, drawn using a Rayleigh formula and the results of the determination of δ¹⁸O (SO₄²⁻) and δ³⁴S (SO₄²⁻) suggest widely varying intensities of the sulphate reduction processes. It can be estimated that bacterial reduction eliminated between 30% and in excess of 50% of the initial concentrations of SO₄²⁻ ions in individual cases.

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An influence of pyrite oxidation on generation of unique acidic pit water: a case study, Podwisniowka quarry, Holy Cross Mountains [south-central Poland]

67%

Migaszewski Z. M. , Galuszka A. , Paslawski P. , Starnawska E.

Polish Journal of Environmental Studies

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2007

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tom 16

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nr 3

407-421

EN

This report presents an assessment of pyrite weathering on the chemistry of water in the abandoned Podwiśniówka quarry of the Holy Cross Mountains (south-central Poland). This quarry did not operate for ore minerals, but for quartzites. The area of the pit pond enlarges each year generally as a result of an influx of spring snowmelt or heavy rainfall. The water examined reveals a very low pH, varying from 2.27 to 3.57 (with geometric mean value of 2.90), and unusual low concentrations of cations and anions, especially total Fe (2.7–24.0 mg·L⁻¹) and SO₄²⁻ (55–285 mg·L⁻¹). With regard to its chemistry, this pond is unique compared to similar sites in Poland and even throughout the world. The low pH and element concentrations are attributed to the specific mineralogy of ore and gangue minerals, as well as complex bacterially catalyzed geochemical processes that have encompassed pyrite oxidation and iron oxidation/hydrolysis reactions.