Avancerad sökning

Visar resultat 1 - 5 av 434 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Fundamental Studies Related to Gaseous Reduction of Iron Oxide

   Författare :Mania Kazemi; Du Sichen; Ioannis Arvanitidis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct reduction; iron ore; cementite; reduction model;

   Sammanfattning : The demands for increasing the efficiency and lowering the environmental effects in iron and steelmaking industries have given rise to interests in application of direct reduction (DR) processes for production of iron by different gases. These advancements require comprehensive models for better control of the process conditions and the product properties. LÄS MER

3. 2. Investigating the parameters that influence the behaviour of natural iron ores during the iron production process

   Författare :Abraham Judah Bumalirivu Muwanguzi; Andrey V Karasev; Henrik Saxèn; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; natural iron ore; iron production; characterization; physical and metallurgical properties; sinter; pellet; direct reduction; low temperature degradation; sample weight; sample positioning; microstructure; reduction degree; solid conversion; Volumetric Model; Grain Model; Random Pore Model; Muko; Uganda;

   Sammanfattning : In the iron production processes, sinters and pellets are mostly used as raw materials due to their consistency with respect to physical and chemical properties. However, natural iron ores, as mined, are rarely used directly as a feed material for iron processing. LÄS MER

4. 3. Recycling of Antimony and Zinc from Metal Oxide Varistors (MOVs)

   Författare :Toni Karlsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carbothermal reduction; metal oxide varistor; zinc; cementation; antimony; recycling; hydrometallurgy; direct reduction; leaching;

   Sammanfattning : .... LÄS MER

5. 4. Theoretical Studies on CO2 Reduction Electrocatalysts

   Författare :Xiaoyu Chen; Mårten S. G. Ahlquist; Sandra Luber; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational Chemistry; CO2 reduction; electrocatalysis; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

   Sammanfattning : The atmospheric CO2 concentration has increased by more than 20% since 1980s and has now reached the highest level than at any point in the past 800 000 years. Electrochemical CO2 reductions are receiving particular in- terest as the apparatus are relatively easy to maintain and cheap to operate. LÄS MER

7. 5. On direct hydrogen fuel cell vehicles : modelling and demonstration

   Författare :Kristina Haraldsson; Per Alvfors; Dougal J. Nelson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; direct hydrogen; Proton Exchange Membrane; PEM; fuel cell; fuel cell vehicle; fuel cell hybrid vehicles; on-board hydrogen storage; Kemiteknik; Chemical engineering; Kemiteknik;

   Sammanfattning : In this thesis, direct hydrogen Proton Exchange Membrane (PEM) fuel cell systems in vehicles are investigated through modelling, field tests and public acceptance surveys. A computer model of a 50 kW PEM fuel cell system was developed. The fuel cell system efficiency is approximately 50% between 10 and 45% of the rated power. LÄS MER