At the 7th VDI conference Emissionsminderung 2024, held on 3 and 4 June 2024 in Nürtingen, CVET GmbH presented new findings on the operation of regenerative thermal oxidisers (RTO) handling hydrogen-containing waste gases.
Dr.-Ing. Olaf Neese had to withdraw from the event at short notice due to illness. Prof. Dr.-Ing. Otto Carlowitz (ret.) stepped in for him, representing CVET GmbH on site together with Dipl.-Ing. J. Leefmann and delivering the presentation with assurance and his customary experience despite the extremely short preparation time. Prof. Carlowitz is the academic teacher and long-standing mentor of several CVET managing directors — that he was able to step in at short notice and deliver the presentation to such a high standard with virtually no preparation is testament to precisely the experience he has passed on to today’s CVET team over the years.
The results, developed jointly with Dipl.-Ing. Ł. Piech and Dipl.-Ing. K.-H. Dammeyer, were presented under the title
“Pre-Ignition in RTO Systems: Analysis and Consequences for Design and Operation”.
The remaining co-authors were not present in person at the conference.
When Hydrogen Reacts Too Early
RTO systems are today part of the standard repertoire of exhaust air treatment. However, where the waste gas contains hydrogen in addition to substances such as carbon monoxide or methane, particular process-engineering effects come into play.
Hydrogen can oxidise very early and very rapidly within the regenerator beds of the RTO — before the remaining exhaust air constituents have reached the temperature level in the combustion chamber required for their complete combustion. The consequence: although the calorific value of the exhaust air should, on a mass and energy balance, permit autothermal operation, complete oxidation cannot be assured without supplementary fuel — and without supplementary fuel, no hot gas can be extracted from the combustion chamber for process heat recovery either.
The paper analysed the phenomenon of pre-ignition and derived process-engineering concepts from it that combine complete oxidation of the exhaust air constituents with the most efficient possible recovery of process energy.
The contribution underlines CVET GmbH’s expertise in the design and optimisation of exhaust air treatment plants, including for demanding waste gas compositions with safety-critical implications.
CVET – Process engineering for a low-emission, future-proof industry.