Sökning: "sulfides"

Visar resultat 16 - 20 av 33 uppsatser innehållade ordet sulfides.

  1. 16. Acid Sulfate Soils and Metal Accumulation in Sediments in Rosån Catchment, Northern Sweden

    Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Carola Lindström; [2017]
    Nyckelord :Acid sulfate soils; increased metal concentrations; anthropogenic activity; Sura sulfatjordar; ökade metallkoncentrationer; mänsklig påverkan;

    Sammanfattning : Global environmental concerns arise when marine deposits with fine-grained iron sulfide-rich sediments (FeS and FeS2), now situated above sea level, oxidize from anthropogenic lowering of the groundwater table. The oxidation of iron sulfides decreases the soil pH and the acidic environment of these Acid Sulfate Soils (AS) soils increase weathering and mobilization of metals into adjacent watercourses, lakes and estuaries. LÄS MER

  3. 17. Modelling of Metal Recovery using Sulfate Reducing Bacteria, Simulation in MATLAB and Aspen Plus

    Master-uppsats, Lunds universitet/Teknisk mikrobiologi; Lunds universitet/Bioteknik

    Författare :Hanna Kvarnström; Erika Lönntoft; [2017]
    Nyckelord :Sulfate reducing bacteria; Metal sulfides; Metal Recovery; Metal precipitation; Modelling; Simulation; Aspen Plus; Matlab; Technology and Engineering;

    Sammanfattning : This report presents a mathematical kinetic model describing the recovery of metal ions as metal sulfides, using sulfate reducing bacteria (SRB). Metal recovery from industrial waste is a potential beneficial and unused source of metals. LÄS MER

  4. 18. Geometallurgical approach to understand how the variability in mineralogy at Zinkgruvan orebodies affects the need for copper activation in the bulk rougher-scavenger flotation

    Master-uppsats, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

    Författare :Ivan Belo Fernandes; [2017]
    Nyckelord :Geometallurgy; Zinkgruvan; Zn-Pb flotation; ore variability; mineral chemistry; pyrrhotite; magnetic separation;

    Sammanfattning : Zinkgruvan is a Pb-Zn-Ag deposit located in south-central Sweden, owned and operated by Lundin Mining. The ore is beneficiated by a collective-selective flotation circuit, recovering both galena and sphalerite in a bulk rougher-scavenger flotation stage and later on separating them into two final products. LÄS MER

  5. 19. Three-dimensional Investigations of Different Sulfides in Steels by Using Electrolytic Extraction

    Master-uppsats, KTH/Materialvetenskap

    Författare :Pang Kit Jerry Lam; [2016]
    Nyckelord :Electrolytic extraction EE ; Manganese sulfides MnS ; Heat treatment HT ; Size; Number density per unit volume Nv ; Morphology; Aspect ratio AR ; Particle size distribution PSD ;

    Sammanfattning : The emphasis of this study is focusing on three-dimensional (3D) investigations of the manganese sulfide (MnS) inclusions characteristics in steels by using electrolytic extraction (EE). Two steel grades, 42CrMo4 and 157C, heat treated (HT) at 900 oC were investigated. LÄS MER

  7. 20. Sulfidförande berggrund i Stockholmsområdet : Riskbergarter och trender

    Kandidat-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Immanuel Åhrberg; [2016]
    Nyckelord :sulfide-bearing rock; Stockholm bedrock; ARD; ABA; NAG; sulfidförande berg; Stockholms berggrund; ARD; ABA; NAG;

    Sammanfattning : Kunskap om svavelhalter i den svenska berggrunden är viktig när bergmassa ska losshållas och bearbetas, oavsett om det gäller gruvbrytning, infrastruktur eller andra byggnationer. Svavel förekommer ofta bundet i sulfider som oxiderar i kontakt med syre och vatten, vilket kan ha en försurande effekt på yt- och grundvatten. LÄS MER