Search for dissertations about: "Lean exhausts"

Found 4 swedish dissertations containing the words Lean exhausts.

  1. 1. NOx reduction with dimethyl ether in lean exhaust

    Author : Sara U Erkfeldt; [2009]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NOx storage; Dimethyl ether; ether; hydrocarbon-SCR; lean NOx reduction; alcohol; Cu-ZSM-5; lean NOx trap; alkane; alternative fuel;

    Abstract : There is a growing concern worldwide about the increase in anthropogenic greenhouse gas emissions, particularly carbon dioxide (CO2) from the combustion of fossil fuels. Vehicles with internal combustion engines contribute significantly to these emissions, which has led to an increased demand for engines running on alternative (non-fossil) fuels. READ MORE

  2. 2. Lean NOx reduction over silver-alumina from lab-scale to real conditions - Effects of reducing agent and catalyst composition

    Author : Fredrik Gunnarsson; [2014]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; ethanol; Ag Al2O3; Pt-doping; Lean NOx reduction; HC-SCR; low-temperature activity; catalyst ageing; biofuels;

    Abstract : Lean NOx reduction over silver-alumina from lab-scale to real conditions Effects of reducing agent and catalyst compositionFREDRIK GUNNARSSONApplied surface chemistryDepartment of Chemical and Biological EngineeringChalmers University of TechnologyAbstractThe focus of this work is to increase the understanding of lean NOx reduction over silver-alumina catalysts using hydrocarbons as the reducing agent (HC-SCR), in particular by investigating the effect of silver loading, the role of platinum doping, and the effect of the type of reducing agent. In addition, the effects of aging and hydrothermal treatment on the catalytic activity and selectivity, and the influence of real engine exhausts were investigated, with special attention to the low-temperature activity. READ MORE

  3. 3. Studies on Lean NOx Reduction with Ammonia. Catalysts and Sensors

    Author : Mikaela Wallin; [2005]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; catalysis; Pt SiO2; NOx reduction; gas sensor; DFT; SCR; H-ZSM-5; in situ FTIR; LCAO; DRIFT; high throughput screening; transient ammonia supply; ammonia; microemulsion; perovskite;

    Abstract : Selective catalytic reduction of NOx with ammonia, NH3-SCR, is a promising technique to reduce NOx under lean conditions, e.g. in diesel engine exhausts. The main objective of this thesis was to gain further understanding of key parameters affecting the performance of catalysts and sensors for NH3-SCR. READ MORE

  4. 4. Studies of a Heavy-Duty Diesel Aftertreatment System Based on the NOX Storage and Reduction Technology

    University dissertation from Department of Chemical Engineering, Lund University

    Author : Klaus Papadakis; Lunds universitet.; Lund University.; [2006]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fuel penalty; injection parameters; DoE; design of experiments; exhaust; diesel engine; NO oxidation; simulation; modelling; oxidation catalyst; NOX trap; NOX storage and reduction; NSR; Kemiteknik och kemisk teknologi; Chemical technology and engineering; dosing strategy; system optimisation;

    Abstract : Popular Abstract in Swedish Gränsvärden för NOX-utsläppen i avgaserna från tunga dieselmotorer kommer att minskas i den Europeiska Unionen från 3,5 g/kWh (Euro IV) idag till 2,0 g/kWh (Euro V) år 2008. I USA och Japan är trenden likadan och utveckling av ett avgassystem för tunga dieselfordon verkar oundviklig. READ MORE