154,692 Works
Economics of biodiesel production
Camilla Christiansen, Anne Skov Ladegaard, Mathias Nordblad & John Woodley
EU has determined that 10 % of all fuel used in 2020 should be replaced by a biofuel. That substitute could be biodiesel. This project deals with the possibility of replacing 10 % of the used fuel in Denmark by biodiesel. Furthermore a comparison of the economic evaluation of two different plants was done. The crucial difference between the plants was purchase of the catalyst, enzymatic or chemical, with a difference of 17.3 mil. kr....
Development of a sustainable fermentation platform
Martin Malthe Borch & Anne Belinda Thomsen
Risøs pretreatment expertice and methods have been used to extract sugars and nutrients from agriculturalwaste. screening have been done with algae and yeast species to test this medium for the industrial potential. further analysis of the nutrient content have been made.
Compost toilets in Roskilde festival
Raphaël Barriol & Guillaume Durand
we thought that there is a very important improvement to do by using composting toilets during Roskilde festival, in terms of environment and hygiene.
Communicating sustainability through interactive design and prototyping of solar cooker
Christian Mebus, Nikolaj Schledermann, Rasmus Funk & Bengt Perers
Cooking and producing clean drinking water is essential in third world countries. Using solar energy for these applications seems obvious and this project focuses on achieving this. It contains design and prototyping of a solar grill using accessible materials in many regards considered garbage after designated use. We build the solar grill from a parabolic shape and a reflective foil. This could be a trashed satellite dish and the wrapping of potato chips. Thus “up...
CO2 absorption from power plants
Tim Sønderby, Kim Carlsen, Nicolas Von Solms & Lars George Kiørboe
This work is on optimizing the absorption of CO2 from post combustion by using MEA(monoethanolamine) as solvent. The aim is to report detailed experimental concentration and temperature profiles for various operation conditions. In this work the height and liquid/gas ratio has been changed to find the optimum operation conditions. The data has been compared with theoretical values based on mathematical models.
Characterization of nanoporous gold electrodes
Erol Zekovic & Xueling Quan
This project investigates the use of nanoporous gold microelectrodes for detection of heavy metals in ground water. By the use of electrochemistry, the change in impendance by adjusting parameters as etching time and poresize, is determined.
Building Intelligence Into Intelligent Buildings
Andreas Møller, David Emil Lemvigh & Christian D Jensen
Most modern "Intelligent" buildings is focused on enhancing the users control when interacting with the building, and simplifying this interaction. BIIIB is different because it analyses its users and then take over the control of the building based on this analysis. We have implemented a simple AI which controls the lighting in the the ground floor hallway of building 322. In this experiment we have managed to cut the time the lamps are turned on...
Black Silicon Solar Cells
Rasmus Schmidt Davidsen & Michael Stenbæk Schmidt
This project aims to optimize the solar cell by applying a new kind of material, black silicon, in order to optimize the absorption of the solar radiation. By changing the surface of the conventional solar cell absorption-material, silicon, on nanoscale, the absorption can possibly and hopefully be improved. If this is the case the next challenge in this project is to incorporate the material in a functioning solar cell, which can actually transform sunlight into...
Black Silicon Solar Cells
Rasmus Schmidt Davidsen & Michael Stenbæk Schmidt
This project aims to optimize the solar cell by applying a new kind of material, black silicon, in order to optimize the absorption of the solar radiation. By changing the surface of the conventional solar cell absorption-material, silicon, on nanoscale, the absorption can possibly and hopefully be improved. If this is the case the next challenge in this project is to incorporate the material in a functioning solar cell, which can actually transform sunlight into...
Bio Meets nano 2010
Anna Kaminska, Frederikke Bahrt & Vimal Katiyar
The project addresses the question of polylactide (PLA) biodegradable plastic and how its properties might be improved, thereby allowing this plant-derived renewable material to be used in a wider range of food packaging applications. In particular, PLA-nanoclay masterbatches will be produced and characterised in the laboratory and selected films produced from these masterbatches will also be studied. As an outcome, we will advance the knowledge base in terms of optimised PLA nanocomposite masterbatch production methods.
Algae Microculture System
Søren Matthias Goldschmidt, Maciej Skolimowski & Kristian Mølhave
This project develops a micro fluidic system for trapping algae in microchambers. The system comprises chambers, valves with a membrane as lock, and filters to provide a growth medium. Membrane strength, stability, deflection, thickness and filter types is studied. When deflection increases, thickness decreases. An applied pressure in the membrane decreases exponentially with time to a pressure above ambient pressure. The relation between the pressure where the growth medium leak through the valve and membrane...
Absorption Chilled Automobile Climate System
Anders Worning Slot, Claus Svend Simonsen, Morten Bjelbo Thomsen & Arne Jørgensen Egelund
In an average combustion engine automobile, more than half of the fuel energy released upon combustion, is lost through dissipated heat. By employing the principle of absorption cooling, our project aims to utilize this excess heat to provide the cooling needed for the car’s climate system. This would in turn increase the fuel efficiency of the average car with up to 10%, as the conventional cooling system in today’s cars is a compressor driven system,...
A VIRTUAL GREENTECH LABORATORY
Mads Tvillinggaard Bonde & Mogens Kilstrup
It is crucial for the development of tomorrows green technologies, to ensure a sufficient engineering work-force in the future. However, application for engineering educations is low. Here I present a virtual laboratory that aims to educate and inspire young people to study greentech engineering. Furthermore, the project aims to reduce the use of chemicals and lab-equipment through replacement of some experiments with in silico simulations. In the virtual laboratory genetic engineering can be applied to...
A Stirling engine powered by the concentrated solar energy reflected by a parabolic reflector
Azur Hodzic, Jesper Andreasen, Martin Holm, Morten Renneberg, Paw Møller & Knud Erik Meyer
The Stirling engine is a heat engine driven by an external heat source in contrast to a normal internal combustion engine. Because of the external independent heat source the Stirling Engine is very versatile in its fuel selection. In modern industry Stirling Engines runs on bio-fuels or waste heat from electricity production. In our project we will use green sustainable energy, by focusing sun rays directly at a Stirling Engine with a parabolic reflector, to...
Analytical modelling as a basis for monitored natural attenuation studies
M. Gutierrez-Neri, P.A.S. Ham, R.J. Schotting, D.N. Lerner & M. Gutierrez-Neri
In this paper, an analytical approach to modelling coupled fringe and core
degradation of a contaminant plume is presented. Explicit steady-state solutions are
derived in three dimensions using a well-known analytical solution for a continuous
planar source problem. These solutions provide rapid methods to evaluate the risk of
subsurface pollution by contaminated groundwater plumes at field sites, particulary
in terms of maximum potential plume length. The resulting fringe-core degradation
model suggests the controlling parameters of...
Linking soil properties to permittivity data: Beyond the Complex Refractive Index Model
Alessandro Brovelli, Giorgio Cassiani & Alessandro Brovelli
The availability of reliable constitutive models linking the bulk electric properties
of porous media to their inner structure is a key requirement for useful quantitative
applications of non invasive methods. In this paper we focus on the use of dielectric
measurements for (time-lapse) monitoring of fluid saturation changes in porous
materials, e.g. via Time Domain Reflectometry (TDR) or ground penetrating radar
(GPR). A number of empirical, semi-empirical and theoretical relationships have been
proposed, linking the...
Geostatistical solution to the inverse problem using surrogate functions for remediation of shallow aquifers
Domenico Bau, Alex Mayer & Domenico Bau
Pump-and-treat (PAT) techniques are often applied to the remediation of dissolved
chemicals from shallow aquifers. A related management problem typically consists of
the selection of the pumping strategy and the most appropriate treatment method, in
order to minimize the total cleanup cost while meeting a set of technical, economic
and social constraints. However, due to scarcity of information about the
hydrogeological system, stochastic modeling approaches seem more appropriate. Of
primary concern is the inherent spatial...
Experimental and Numerical Study to Investigate Dynamic Capillary Pressure Effect in Two-Phase Flow in Porous Media
Simona Bottero, Majid Hassanizadeh & Simona Bottero
Experimental and Numerical Study to Investigate Dynamic Capillary Pressure Effect
in Two-Phase Flow in Porous Media
Simona Bottero, Majid Hassanizadeh
Department of Earth Sciences, Utrecht University, P.O.Box 80021, 3508 TA Utrecht,
The Netherlands
It is known from literature that traditional equations describing two-phase flow
processes in porous media may be inadequate in case of non-equilibrium or dynamic
condition.
In the latest theory an additional dynamic term is proposed such that capillary
pressure may depends on...
On the equivalence of measured and averaged pressures in porous media:
Cas Berentsen, S. Majid Hassanizadeh & Cas Berentsen
Fluid pressure in porous media is commonly measured by means of a manometer or a
pressure transducer. The measurement is actually done on a body of fluids just
outside the porous medium, which is in hydraulic contact with the fluid just inside
the porous medium. It is almost always assumed that the measured pressure is equal
to some volumetric average pressure of the fluid inside the porous medium.
This major assumption however, has never been...
Behaviour of mixed finite element and multipoint point flux approximations for flow with discontinuous coefficients
Vincent FONTAINE, Anis YOUNES & Vincent FONTAINE
We study the numerical behaviour and the relationships between some numerical
methods derived from the Mixed Finite Element (MFE) formulation and from the
Control Volume formulation using the Multi-Point Flux Approximation (MPFA) of
Aavatsmark et al. (1996).
All methods are locally mass conservative and are well suited to solve the flow
problem for both steady state (elliptic case) an transient (parabolic case) on a
general irregular grid with anisotropic and heterogeneous discontinuous
coefficients.
Hybridization of...
Parameter Sensitivity in the Predication of DNAPL Infiltration and Redistribution in Heterogeneous Porous Media
Tissa Illangasekare, Mini Mathew, Fritjof Fagerlund, Auli Niemi & Tissa Illangasekare
Subsurface heterogeneity has a significant influence on infiltration and distribution of DNAPLs. Numerical
models of multiphase flow are limited by their ability to predict behavior of DNAPLs in the field due to lack of
accurate data on characterization of heterogeneity. However, these models help to obtain insights into the
complex behavior that will be useful in designing effective remediation schemes. A number of multiphase
flow codes that have the ability to capture the fundamental processes...
Fluid Circulation in Coupled Free and Porous Domain: Implications of Porous Media Heterogeneity
Diganta Das, Mark Lewis & Diganta Das
Fluid flow in coupled free and porous domain, particularly when the porous medium is
heterogeneous, is encountered in many hydro-environmental conditions. These include,
e.g., groundwater hydrology, conjunctive surface and subsurface flow, mud cake
formation during drilling of oil wells and others. One of the most difficult
problems in the study of coupled flow behaviour has been the development of a
universally applicable modelling scheme for combining the flow regimes. This is
because the free/porous interfacial...
Redox processes on a grain scale, the possible effect of organic matter in stagnant inter/intra-granular voids
Rasmus Jakobsen & Rasmus Jakobsen
The presence of stagnant zones in porous media is often used to explain the
observations of self-contradictory redox chemistry once the possibilities of borehole
mixing are ruled out. As an example, methane is found in very small amounts in many
suboxic groundwaters, though methanogenesis requires very reduced conditions (high H2
levels) in order to be thermodynamically feasible. This feature has been produced in
a previous model using a simple dual-porosity 1-D PHREEQC model (Jakobsen, 2002),...
A Three-Dimensional Lattice-Boltzmann Model for Bacterial Chemotaxis: Traveling Bands and Groundwater Bioremediation
Markus Hilpert, Long Wei & Markus Hilpert
We present a Lattice-Boltzmann model for bacterial chemotaxis that
accounts, at the pore scale, for advective-diffusive transport of
the bacteria and a reaction of the bacteria with a chemoattractant.
The model was validated by simulating experiments on the degradation
of naphthalene by Pseudomonas putida in a capillary tube
containing either bulk liquid or glass beads. Naphthalene was
initially uniformly distributed in the void space of a tube. Then,
one tube inlet was brought into contact...
Subsurface Characterization Using Geophysical and Geohydrological Data Fusion
Metin Ozbek, James Ross, George Pinder & Metin Ozbek
We are introducing a novel technology applicable to the robust
interpretation of the spatial distribution of hydraulic conductivity in
heterogenous formations. The evidence theory approach is based on a
combination of directly measured hydrogeological and geophysical data
together with expert opinion. The approach first utilizes fuzzy-set based
approximate reasoning to quantify subjective expert opinion, especially
when data are scarce, to create a fuzzy prior characterization of the
hydraulic conductivity field. Subjective information includes, but is...
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Resource Types
Affiliations
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French National Centre for Scientific Research38
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Duke University21
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University of British Columbia20
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The University of Texas at Austin16
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Centre for Ecology & Hydrology13
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UK Centre for Ecology & Hydrology13
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University of Montpellier10
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University of Sheffield10
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University of Cambridge9
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Indiana University9