Search for dissertations about: "raffinering"

Showing result 1 - 5 of 11 swedish dissertations containing the word raffinering.

2. 1. Slag/Metal Metallurgy in Iron and Steel Melts

   Author : Johan Ekengård; Pär Jönsson; Attila Dioszegi; Johan Björkvall; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; austenit; syreaktivitet; slagg; fördelning; primär dendrit; metalldroppar; lamellär grafit; svavel; kompaktgrafit; skänk; nodulär grafit; raffinering; Metallurgical process science; Metallurgisk processvetenskap;

   Abstract : In this work, the metal and slag phase mixing in three steps of a ladle refining operation of steel melts and for an oxygen balance during cooling of cast iron melts have been studied at two Swedish steel plants and at two Swedish cast iron foundries, respectively. In order to predict the oxygen activity in the steel bulk in equilibrium with the top slag as well as in metal droplets in the top slag in equilibrium with the top slag, three slag models were used. READ MORE

4. 2. Process intensification in mechanical pulping : Reduced process complexity and improved energy efficiency

   Author : Christer Sandberg; Per Engstrand; Jan-Erik Berg; Göran Bengtsson; Mittuniversitetet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : This work shows that, for newsprint quality grades, the production processes for mechanical pulp can be simplified, and the specific electrical energy demand can be reduced with around 600 kWh/ton (30%). The purpose of the work is to demonstrate how the production cost for mechanical pulps can be decreased through increased energy efficiency and reduced number of unit operations. READ MORE

5. 3. Measurement of shear force, temperature profiles and fibre development in mill-scale TMP refiners

   Author : Hans-Olof Backlund; FSCN - Fibre Science and Communication Network; []
   Keywords : Shear force; Tangential force; Temperature profile; Thermomechanical pulping;

   Abstract : Two different force sensors have been developed for tangential forcemeasurements in commercial TMP refiners, one is based on the use of piezoelectricsensors and the other on strain gauges. The measurements are used to learn moreabout the refining mechanism in both single-disc (SD) refiners and conical disc(CD) refiners. READ MORE

6. 4. Towards a Sustainable Biomass and Waste Refinery Based on Pyrolysis Combined with a Pretreatment Process

   Author : Yuming Wen; Weihong Yang; Pär Jönsson; Tobias Richards; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pyrolysis; anaerobic digestion; hydrothermal carbonization; refinery; biomass; waste; kinetics; LCA; Energiteknik; Energy Technology; Chemical Engineering; Kemiteknik;

   Abstract : Some of the naturally accumulated biomass and the massive production of waste by human activities have caused serious environmental problems. The degradation of biomass and waste is one of the main greenhouse gasses (GHG) emission sources. READ MORE

7. 5. A study of the autogenous Hydrogen-DRI slag and its impact on the dephosphorization of fossil-free steel at different oxygen potentials

   Author : Joar Huss; Pär Jönsson; Du Sichen; Niklas Kojola; Chris Pistiorius; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials Science and Engineering; Teknisk materialvetenskap;

   Abstract : The present study comprises aspects related to the phosphate capacity, the dephosphorization of fossil-free steel, and the utilization of potential by-products. The focus is mainly given to the functions and impact of the autogenous H-DRI slag in the dephosphorization process and the possibility for future slag valorization. READ MORE