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Showing result 1 - 5 of 19 swedish dissertations matching the above criteria.

2. 1. REACTIVE TRANSPORT MODELLING OF DISSOLVED CO2 IN POROUS MEDIA : Injection into and leakage from geological reservoirs

   Author : Nawaz Ahmad; Anders Wörman; Auli Niemi; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CO2 geological storage and safety; leakage of brine saturated with dissolved CO2; reactive transport; fracture; advection; dispersion and diffusion; sorption; carbonate minerals kinetic reactions; calcite; dolomite; siderite; porosity; permeability; heat transport; Land and Water Resources Engineering; Mark- och vattenteknik;

   Abstract : The geological sequestration of carbon dioxide (CO2) is one of the options of controlling the greenhouse gas emissions. However, leakage of CO2 from the storage reservoir is a risk associated with geological sequestration. Over longer times, large-scale groundwater motion may cause leakage of dissolved CO2 (CO2aq). READ MORE

4. 2. Internal Erosion Phenomena in Embankment Dams : Throughflow and internal erosion mechanisms

   Author : Farzad Ferdos; Anders Wörman; Bijan Dargahi; Fredrik Johansson; Willi Hager; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Internal erosion modelling in porous material; Constitutive law of erosion for closure of continuum-mechanics-based balance equations for numerical modelling; High Reynolds-number turbulent flow; Flow laws; Coarse rockfill material throughflow; Computational Fluid Dynamics.; Civil and Architectural Engineering; Byggvetenskap;

   Abstract :  In this study, two major internal erosion initiation processes, suffusion and concentrated leak mechanisms, which lead to both defect formation in a dam’s body and its foundation and high throughflow in dams subjected to internal erosion were studied. This understanding has the potential to facilitate numerical modelling and expedite dam safety assessment studies. READ MORE

5. 3. Filtration System For On-Site Wastewater Treatment : Experiences From Modelling and Experimental Investigations

   Author : Rajabu Hamisi; Gunno Renman; Anders Wörman; Scholz Miklas; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Land and Water Resources Engineering; Mark- och vattenteknik;

   Abstract : Many on-site wastewater treatment systems in Sweden are not sustainable in terms of treatment efficiency, nutrient recycling and economics. Achieving reliable and sustainable systems to meet on-site wastewater treatment demands requires comprehensive field investigations of the performance of novel technologies. READ MORE

6. 4. Effect of Hyporheic Exchange on Conservative and Reactive Solute Transport in Streams : Model Assessments Based on Tracer Tests

   Author : Karin Jonsson; Anders Wörman; Bernhard H. Schmid; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; conservative; hyporheic exchange; model; reactive; retention; solute; sorption kinetics; stream transport; temporal moments; tracer experiment; Geovetenskap; Earth sciences; Geovetenskap; Sedimentology; sedimentologi;

   Abstract : Understanding of the processes affecting solute transport in flowing water is important for the possibility to predict the evolution with time of polluted stream systems. This thesis presents tracer experiment methodology and model developments for solute transport in streams, with special focus on retention processes and their effect on solute stream transport. READ MORE

7. 5. Coupled Hydrological and Microbiological Processes Controlling Denitrification in Constructed Wetlands

   Author : Johan Kjellin; Anders Wörman; Sara Hallin; Barbro Ulén; Björn Klöve; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Constructed wetland; Residence time; water flow modeling; denitrification rate; Tracer experiment; denitrifying bacteria community structure; Water in nature and society; Vatten i natur och samhälle;

   Abstract : Treatment wetlands play an important role in reducing nitrogen content in wastewater and agricultural run-off water. The main removal process is denitrification and the removal efficiency depends on the hydrological and microbiological features of the wetland, especially in terms of water residence times and denitrification rates. READ MORE