Katalytische Stickstoffmonoxid Abscheidung an einem CSCR®-Testreaktor mit Ammoniak als Reduktionsmittel

Translated title of the contribution: Catalytic nitrogen monoxide reduction on a CSCR®-testreactor with ammonia as reducing agent

Michael Miletich

Research output: ThesisMaster's Thesis

966 Downloads (Pure)

Abstract

The CSCR®-process (Carbon Catalytic Selective Reduction) is applied in the field of flue gas denitrification (DeNOx). The CSCR®-method is used for large flue gas flows. By connecting two CSCR®-reactors a simultaneous reduction of SO2 and NO is possible. In a subsequent step activated coke can be regenerated and then reused in a circulation with a low amount of residues. Activated coke is characterized as an adsorbens for air pollutants such as nitrogen oxides (NOx) and sulfur dioxide (SO2) because of its large B.E.T.-surface. Additionally, it offers the possibility to act as a catalyst to reduce the adsorbed nitrogen oxide by ammonia to harmless molecules. The CSCR®-method is tested in a specially built test facility. The bedheight of activated coke in the testing plant corresponds to that bedheight which is used in a real sintering gas cleaning plant. Thereby, it is possible to obtain comparable results. The testing conditions as concentration of ammonia, nitrogen oxide and water vapor are varied during the test series. In addition to the adsorption- and reductiontests with activated coke, desorption experiments have been carried out. The results of the desorptiontests provide information about the coke-bound ammonia molecules which are depending on temperature. On the one hand the results of the test series confirm the bad adsorption ability of activated carbon by adsorbing nitrogen oxides on the surface, and on the other hand the inhibitory effect of water vapor for the catalytic reduction of NO by ammonia. Thus, in the adsorption experiments a NO-breakthrough is detected in a few minutes. The reduction of nitrogen oxides at 6% vol. humidity is up to 95%. At 12% vol. humidity the limit value is also achieved. The reduction amounts to 80% at an ammonia slip below 30 ppm, dry. However at 20% vol. humidity the required limit value cannot be achieved without producing excessive ammonia slip.
Translated title of the contributionCatalytic nitrogen monoxide reduction on a CSCR®-testreactor with ammonia as reducing agent
Original languageGerman
QualificationDipl.-Ing.
Supervisors/Advisors
  • Lehner, Markus, Supervisor (internal)
Award date28 Jun 2013
Publication statusPublished - 2013

Bibliographical note

embargoed until 29-04-2018

Keywords

  • Denitrification
  • Nitrogen monoxide
  • Catalytic reduction
  • CSCR
  • Activated coke

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