Sökning: "refining intensity"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden refining intensity.

1. 1. Reduction of refining energy during mechanical pulping : using pressurised chip compression and sulphite pre-treatment

   Författare :Erik Nelsson; Geoffrey Daniel; Mittuniversitetet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Chip pre-treatment; double disc refiner; energy efficiency; Impressafiner; low dosage; Norway spruce; refining intensity; single disc refiner; sulphite pre-treatment; thermomechanical pulp;

   Sammanfattning : The effects of pressurised compressive chip pre-treatment and low dosage sulphite pre-treatment were evaluated for production of thermomechanical pulp in mill scale trials using Norway spruce (Picea abies) at the Braviken paper mill (Holmen Paper AB, Sweden). The general aim of the study was to improve the energy efficiency during the production of mechanical pulps suitable for news and improved news grade papers. LÄS MER

3. 2. Improved energy efficiency in double disc chip refining

   Författare :Dino Muhic; Per Engstrand; Lars Sundström; Mats Ullmar; Christer Sandberg; Hans Höglund; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermomechanical pulping TMP ; double disc refining; high intensity; Chemical engineering; Kemiteknik;

   Sammanfattning : The electrical energy consumption in thermomechanical pulping (TMP) is very high, in the range of 2 – 3 MWh/adt depending on process solution and on the product quality specifications for the paper product. Both pulpwood and energy prices have increased rapidly for some time. LÄS MER

4. 3. Frictional studies and high strain rate testing of wood under refining conditions

   Författare :Birgitta Svensson; Hans Höglund; Per A. Gradin; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Friction; High strain rate testing; Wood; Mechanical pulping; Tribology; Refining; Energy consumption; Chemical engineering; Kemiteknik;

   Sammanfattning : When producing thermomechanical pulps (TMP), wood chips and fiber material are loaded mechanically in a disc-refiner to separate the fibers and to make them flexible. In the process, much of the energy supplied is transferred to the fiber material through cyclic compression, shear and friction processes. LÄS MER

5. 4. Process Intensification through Acoustic and Hydrodynamic Cavitation

   Författare :Taraka Rama Krishna Pamidi; Örjan Johansson; Torbjörn Löfqvist; Giancarlo Cravotto; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultrasonic Cavitation; Hydrodynamic Cavitation; Process Intensification; Cellulose fiber; Tungsten; Refining; Leaching; Teknisk akustik; Engineering Acoustics;

   Sammanfattning : Process industries are cornerstones in today’s industrialized world. They contribute significantly to the development of diverse commodities and materials that are used in our daily lives. Process intensification is an approach implemented to boost manufacturing efficiency and capacities in a more sustainable and energy efficient way. LÄS MER

7. 5. Improved energy efficiency in mill scale production of mechanical pulp by increased wood softening and refining intensity

   Författare :Erik Nelsson; Per Engstrand; Birgitta A. Engberg; Rodger Beatson; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : This thesis focuses on the electric energy efficiency of single stage double disc refining for production of printing grade mechanical pulp from Norway spruce wood chips. The thesis is based on the hypothesis, that more energy efficiency refining can be attained by balanced increases of wood softening and refining intensity. LÄS MER