Search for dissertations about: "Digester"

Showing result 1 - 5 of 35 swedish dissertations containing the word Digester.

  2. 1. ANALYZING THE HYDRO DYNAMICS AND THE CHEMICAL REACTIONS IN PULP DIGESTER SYSTEMS USING CFD MODELLING

    Author : Bijan Pourian; Erik Dahlquist; Laszlo Fuchs; Mälardalens högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; MODELLING; SIMULATION; PULP; DIGESTER. CHEMICAL; MULTIPHASE; Cellulose and paper engineering; Cellulosa- och pappersteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

    Abstract : The aim of this thesis is to use differential analysis and finite volume method (FVM) to model and analyze a continuous pulp digester in order to create a detailed picture of the flow behaviour and chemical reactions in the digester. This information will be used to optimize wood chip flow and reactions and to diagnose and avoid faults such as hang-ups and channelling. READ MORE

  4. 2. Digester modelling for diagnostics and control

    Author : Johan Jansson; Erik Dahlquist; Thore Berntsson; Mälardalens högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pulp production; diagnostics; simulation; control; Cellulose and paper engineering; Cellulosa- och pappersteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

    Abstract : This thesis will show the possibility for the development and use of an on-line model for application to continuous digesters for pulp production. The model is developed by using a program called Dymola (Dynamic Modeling Laboratory). What makes the Dymola software so well suited is that the program solves equations simultaneously. READ MORE

  5. 3. Risk of nitrous oxide emissions and potential of bioaugmentation when treating digester supernatant via nitrification-denitrification

    Author : Fredrik Stenström; Avdelningen för kemiteknik; []
    Keywords : Bioaugmentation; Digester supernatant; Inoculation; Nitrification-denitrification; Nitrifiers; Nitrous oxide emissions; Reject water; Bioaugmentation; Digester supernatant; Inoculation; Nitrification-denitrification; Nitrifiers; Nitrous oxide emissions; Reject water;

    Abstract : This thesis examines two different impacts of sidestream treatment of digester supernatant via nitrification-denitrification in a sequenced batch reactor (SBR). One of the impacts is the detrimental formation of nitrous oxide, and the other is the positive boosting of nitrifiers to the mainstream process through bioaugmentation. READ MORE

  6. 4. Anaerobic Digester Fluid Rheology and Process Efficiency : Interactions of Substrate Composition, Trace Element Availability, and Microbial Activity

    Author : Luka Šafarič; Annika Björn; Sepehr Shakeri Yekta; David Bastviken; David C Stuckey; Linköpings universitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Anaerobic digestion; biogas; rheology; trace elements; microbiology; Anaerob rötning; biogas; reologi; spårämnen; mikrobiologi;

    Abstract : As the anthropogenic greenhouse gas emissions continue imposing stress on our environment, it is becoming increasingly important to identify and implement new renewable technologies. Biogas production through anaerobic digestion has a great potential, since it links waste treatment with extraction of renewable energy, enabling circular bio-economies that are vital for a sustainable future. READ MORE

  7. 5. Renewables Based Polygeneration for Rural Development in Bangladesh

    Author : MD. Ershad Ullah Khan; Andrew R. Martin; Semida Silveira; Peter Hagström; Jochen Bundschuh; Erik Ahlgren; Marcus Öhman; Monica Odlare; Lasse Aistrup Rosendahl; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Anaerobic digester; solar PV; polygeneration; cooking gas; gas engine; electricity; membrane distillation; arsenic safe water; Anaerobisk rötkammare; solceller; polygenerering; matlagningsgas; gasmotor; elektricitet; membrandestillering; arsenikfritt vatten; Energy Technology; Energiteknik;

    Abstract : Despite the country's rural electrification programme, kerosene is the predominant source for lighting, and unsustainable and polluting woody biomass is virtually the only option available for cooking. The rural population also struggles with unsafe drinking water in terms of widespread arsenic contamination of well water. READ MORE