New project aims to significantly reduce four-stroke methane slip
MAN Energy Solutions has announced that it is developing an oxidation catalyst for four-stroke engines that will significantly reduce methane slip. Called ‘IMOKAT II’ and developed at MAN Energy Solutions’ headquarters in Augsburg, Germany, the research project is currently undergoing testing at the company’s Frederikshavn, Denmark facility, according to the company's release.
Funded by the German Federal Ministry for Economics and Climate Action, the new project will investigate the operational experience of a pre-turbo methane-oxidation catalyst, ultimately aiming for a 70% reduction of methane emissions at 100% load.
Whereas predecessor project, IMOKAT I, investigated different catalytic materials and uncovered a sulphur-resistant material without any precious metals that facilitated high methane-conversion, IMOKAT II is a prototype and technology demonstrator. In this context, it is currently investigating the material’s potential on a test engine with the major goal of designing a catalyst solution that can be applied to a full-scale engine to reduce methane emissions in the field. Field testing aboard a vessel is scheduled for Q1 2024.
The catalyst material chosen without precious metals is sulphur-resistant, which is an important design consideration as – even during gas operation – pilot- and lube-oils contain traces of sulphur. It also means that it is possible to preheat the catalyst in diesel mode before switching to gas operation, where a cold catalyst would not be able to perform optimally and methane slip would occur.
MAN Energy Solutions reports that pre-turbocharger integration of the catalyst is necessary because of the exhaust-gas pressure and temperature level there. Integration is much more complex there compared to a post-turbocharger installation, as is found with SCR (Selective Catalytic Reduction).
