Sökning: "Zinc Sulfate"

Visar resultat 6 - 10 av 16 uppsatser innehållade orden Zinc Sulfate.

1. 6. Mineralogical speciation of sulfur in acid sulfate soils from Luleå, Sweden

   Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Geovetenskap och miljöteknik

   Författare :Niklas Gunnarsson; [2018]
   Nyckelord :acid sulfate soil; metal leakage; low pH; SEM; elemental sulfur; framboidal pyrite;

   Sammanfattning : Marine sulfide – bearing sediments that oxidize when in contact with oxygen and leach outelements in high concentrations to small watercourses have been a problem for many years allover the world especially around the Bothnian Bay. The purpose of this study was to furtherinvestigate the sulfur mineralogy present in acid sulfate soils in the area of Luleå, Sweden. LÄS MER

3. 7. Corrosion initiation induced by sodium sulfate and sodium chloride particles on Cu and the golden alloy Cu5Al5Zn at simulated atmospheric conditions

   Master-uppsats, KTH/Materialvetenskap

   Författare :Weijie Zhao; [2017]
   Nyckelord :atmospheric corrosion; sodium sulfate; sodium chloride; Cu5Al5Zn; Cu metal; mixed salt pre-deposition; laboratory exposure; LOM; SEM EDS; ATR-FTIR; cathodic reduction;

   Sammanfattning : Effects of sodium sulfate (Na2SO4) particle deposition on the atmospheric corrosion of copper (Cu) metal and a Cu-based alloy (Cu5Al5Zn) used in architectural applications were investigated at laboratory conditions compared with effects induced by sodium chloride (NaCl) and to some extent ammonium sulfate (NH4)2SO4 induced corrosion. Pre-deposited surfaces were exposed to repeated wet/dry conditions in a climatic chamber and the formation of corrosion products were assessed using light optical microscopy (LOM), scanning electron microscopy with elemental analysis (SEM/EDS), Fourier transform infrared techniques (FTIR microscopy) and cathodic reduction (CR). LÄS MER

4. 8. 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

5. 9. 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

7. 10. 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