Sökning: "Ferrous sulphate"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Ferrous sulphate.

  1. 1. Influence of acid hydrogen peroxide treatment on refining energy and TMP properties

    Författare :Karin Walter; Per Engstrand; Magnus Paulsson; Lennart Salmén; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TMP; Black Spruce; Energy reduction; Hydrogen peroxide; Ferrous sulphate; Refining; Inter-stage treatment; Pulp and paper properties; Fenton´s reagent; Bleaching; Sodium dithionite; Brightness; Metals; Fibre dimensions; Cross-sectional dimensions; Chemical composition; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : The potential of using acid hydrogen peroxide under Fenton conditions to lower the electrical energy consumed during the production of Black spruce (Picea mariana) thermomechanical pulp (TMP) was investigated. The chemical system, which consisted of ferrous sulphate, hydrogen peroxide and optionally an enhancer (3,4-dimethoxybenzyl alcohol, ethylenediaminetetraacetic acid or oxalic acid/sodium oxalate), was evaluated as an inter-stage treatment where the primary refiner was used as a mixer. LÄS MER

  3. 2. MRI evaluation and image processing in gel dosimetry. A study of selected MRI properties and image processing in 3D gel dosimetry

    Författare :Peter Magnusson; Malmö Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Klinisk fysiologi; medical instrumentation; tomography; radiology; Clinical physics; image registering; multi-slice; slice profile; ferrous sulphate; polyacrylamide; 3D volume acquisition; RF field; B1 field; relaxation time; T1; T2; spin-echo; multi-spin-echo; stochastic noise; nonuniformity; SNR; radiologi; tomografi; medicinsk instrumentering; Radiopharmaceutical technology; Radiofarmaceutisk teknik; Physics; Fysik;

    Sammanfattning : Gel dosimetry is a new dosimetry method applied in radiation therapy. Gel dosimeters consist of a radiation sensitive gel, which can integrate absorbed doses from several radiation sources or beams. The dose to the gel can be evaluated by magnetic resonance imaging (MRI), a procedure that is the focus of the present thesis. LÄS MER

  4. 3. Chalcopyrite Dissolution in Sulphate-Based Leaching and Bioleaching Systems

    Författare :Mohammad Khoshkhoo; Wolfgang Sand; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Process Metallurgy; Processmetallurgi;

    Sammanfattning : Chalcopyrite (CuFeS2) is the most abundant and the most economically important copper mineral. Increasing worldwide demand for copper accompanied by exhaustion of copper resources necessitate the development of new processes for treating lower-grade copper ores. LÄS MER

  5. 4. The use of Fenton chemistry for reducing the refining energy during TMP production : the effect of free ferrous and free or chelated ferric ions

    Författare :Karin Walter; Per Engstrand; Magnus Paulsson; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The potential of using acid hydrogen peroxide under Fenton conditions to lowerthe electrical energy consumed during the production of Black spruce (Piceamariana) thermomechanical pulp (TMP) was investigated in pilot scale. Thechemical system, which consisted of ferrous sulphate, hydrogen peroxide andoptionally an enhancer (such as a chelating agent), was evaluated as an inter-stagetreatment. LÄS MER

  7. 5. Flotation chemistry of complex sulphide ores : recycling of process water and flotation selectivity

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

    Sammanfattning : Recycling of flotation effluents through the ore processing plant is one of the ways of reducing both plant-operating costs and industrial impact onto the local ecosystem. Such waters named acid mine drainage (AMD), if discharged from sulphide flotation are gypsum (CaSO4.H2O) saturated and have a high salinity (on the order of 1000 ppm). LÄS MER