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Auflistung nach Autor:in "Horner, Christoph"

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  • Konferenzbeitrag
    A Coupled Model for Transport, Geochemistry and Redox Processes
    (The Information Society and Enlargement of the European Union, 2003) Horner, Christoph; Holzbecher, Ekkehard; Wiese, Bernd; Nützmann, Gunnar
    A reactive multicomponent chemical transport model to describe redox processes during bank-filtration dealing with equilibrium chemistry and Kinetics of biodegradation is presented. The model approach considers hydrodynamic transport, biodegradation kinetics and equilibrium chemistry speciation. Due to their different mathematical character the transport and reaction model subsets are coupled by a two step procedure (“operation splitting”). The multi species hydrodynamic advection-dispersion subset is a partial differential equation system, the Kinetics subset are ordinary differential equation systems, and the equilibrium subset is a nonlinear algebraic equation system. The model was set up using user friendly software tools as ModelMaker 3 an MATLAB4 which offer powerful tools to solve partial differential and ordinary differential equation systems. The model is demonstrated to three test-cases typical for river bank-filtration and verified by available geochemical software. Topic: Modelling and simulation of environmental systems
  • Konferenzbeitrag
    Modelling Assessment of an in situ Oxygen Sparging Remediation of an Ammonium Contamination - Pilot Plant BIOXWAND Berlin
    (Environmental Informatics and Systems Research, 2007) Horner, Christoph; Engelmann, Frank; Schmolke, Lutz-Peter; Nützmann, Gunnar
    Reactive transport modelling is demonstrated by assessing the remediation of an Ammonium contamination plume originating from sewage field management over decades and situated close to the Friedrichshagen water works in Berlin. As remediation method, an in situ nitrification of the aquifer by injection of Oxygen gas and Air close to the production wells will be performed. In order to assess the kernel process itself (the nitrification), but also its impact on the hydrochemical composition of the raw water to be pumped from water works production wells, reactive transport modelling was performed. First, principal aspects of the coupling of hydrodynamic transport and reactive software tools are presented. In order to assess the remediation by in situ nitrificaton a site and problem adapted reaction network has to be deduced, followed by the mathematical formulation and by the incorporation of reactive terms into a reactive transport solver. Two model versions result from these steps: (1) a generic regional model set up to evaluate the long-term reaction zoning to expect due to permanent Oxygen gas injection, and (2) a verification of the monitored hydrochemistry during a first field test to estimate reaction parameters for further field tests planned in future closely to the well fields.