Search Results

Beginning with the interim Tier 4 legislation in the US, off-highway engines with 56 - 560 kW are required to reduce Particulate Matter (PM) emissions to less than 0.02 g/kWh. While this significant reduction in PM emissions represents a great new challenge for off-highway engines, it can be achieved with a combination of engine measures and PM aftertreatment technologies. An engine with high engine out PM emissions would require a wall flow filter which has to be frequently actively regenerated at temperatures above 600 degree C and requires measures to address ash collection. On the other hand, an engine with low to moderate engine out PM emissions could be fitted with a passively regenerated partial filter such as the PM-Metalit, with no need for frequent high temperature soot regeneration or ash removal maintenance [1, 2]. A PM-Metalit system is constructed solely from metal and thus is extremely robust against severe mechanical loads that are present in off-highway applications.