The NOx limit value is adjusted within the engine via the fuel-air mixture, the CO limit value is still well below even with strongly deactivated catalytic converters. In order to increase the service life of the catalyst, it is important to know that the formaldehyde measurement result is significantly influenced by two factors:
– The formaldehyde emissions, which correlate directly with the level of methane slip
– The activity of the built-in catalyst.
In order to achieve the best possible formaldehyde measurement results with an already installed catalyst, it is therefore very important to work with a very good ignition (spark plugs, ignition coils, ignition timing setting) as well as to burn biogas in high methane concentrations. (see also “Why is a good ignition so important?”) The activity of a fresh catalyst is insignificant. All fresh catalysts are good. The decisive factor is that the catalyst technology is coordinated in such a way that it is
deactivated as slowly as possible by the catalyst poisons of the biogas (see also Technology. The sulphur-resistant catalyst developed by Emission Partner is a technology that has been specially developed for biogas applications: in addition to the sulphur in biogas, the engine oil ash deactivates the catalyst most strongly. Zinc- free engine oils, whose ashes can be blown off the catalyst surface, have proved to be advantageous. (Mobil Pegasus 610/705/1005 and Tectrol Methaflexx HC Plus (download specification here, see appendix). We recommend that the catalytic converter is cleaned of oil residue every 6 months.
Emission Partner therefore only offers catalysts that are very easy to install and remove for maintenance or easy replacement, and if the above points are taken into account, Emission Partner catalysts also reach formaldehyde values below the limit for second and now even for third party measurements.