Sökning: "galena"

Visar resultat 6 - 10 av 22 avhandlingar innehållade ordet galena.

  1. 6. Sulphide mineral flotation : a new insight into oxidation mechanisms

    Författare :Alireza Javadi; Jan D. Miller; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mineralteknik; Mineral Processing;

    Sammanfattning : Formation of hydrogen peroxide (H2O2), an oxidizing agent stronger than oxygen, by sulphide minerals during grinding was investigated. It was found that pyrite (FeS2), chalcopyrite (CuFeS2), sphalerite ((Zn,Fe)S), and galena (PbS), which are the most abundant sulphide minerals on Earth, generated H2O2 in pulp liquid during wet grinding in the presence or devoid of dissolved oxygen in water and also when the freshly ground solids are placed in water immediately after dry grinding. LÄS MER

  3. 7. A spectroscopic study of mechanically activated sulphide minerals

    Författare :Benoit Drouet; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

    Sammanfattning : Sulphide minerals are a major source of non-ferrous metals such as lead, zinc or copper. Ores are processed to be selectively separated which can be achieved by flotation. LÄS MER

  4. 8. Roasting of Cu-rich complex concentrates - A mineralogical investigation

    Författare :Pande Nishant Prasad; Caisa Samuelsson; Andreas Lennartsson; Pekka Taskinen; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Process Metallurgy; Processmetallurgi;

    Sammanfattning : Copper has assumed importance as a metal which is essential for realization of a sustainable modern society. Demand for copper is sharply increasing, and a supply shortfall is shortly anticipated. Such a scenario could adversely affect some of the major transformations directed toward reversal of climate change. LÄS MER

  5. 9. Recycling process water in complex sulphide ore flotation

    Författare :Fatai Kolawole Ikumapayi; Jaako Olavi Leppinen; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mineral Processing; Mineralteknik;

    Sammanfattning : An approach to environmental sustainability and improved process economy in sulphide minerals production is recycling of process water in flotation of complex sulphide ores. However process water chemistry may be a critical issue to flotation efficiency. Process water discharged from sulphide flotation circuits are usually gypsum (CaSO4. LÄS MER

  7. 10. Flotation selectivity, process modelling and simulation for a complex sulphide ore

    Författare :Xuemin Yuan; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mineralteknik; Mineral Processing;

    Sammanfattning : This thesis covers research with different methods on the same fine-grained complex sulphide ore - Petiknäs - from the Skellefte Field in Northern Sweden. Mineralogical research results demonstrate that the degree of liberation of galena, rather than the chemical factors under the current flotation conditions, is the dominant factor affecting Pb grade and recovery, since galena has the same flotation as chalcopyrite if having the same degree of liberation. LÄS MER