The Influence of Lubricating Oil and Diesel Fuel on Ash Accumulation in an Exhaust Particulate Trap

A diesel generator set was used as a long term durability test for an exhaust particulate trap oxidizer system. The single trap (wall flow monolith) system was exposed to two 3000 hour tests. The tests included 20 minute engine cycles of varying speeds and loads, with complete monitoring of trap performance during loading and regeneration. The two tests differed in the type of lubricating oil and fuel used. The first test used a relatively high ash oil and regular sulfur fuel. The second test used an ashless oil and low sulfur fuel. The affects on the ceramic filter performance over the extended test times were dramatically different. The regular sulfur fuel and high ash of the first test resulted in a trap almost completely filled with ash. The low sulfur fuel and ashless oil of the second test had only 6% by mass of the ash collected in the previous test. The use of an experimental ashless lubricating oil and low sulfur fuel resulted in only modest noncombustible deposits in the exhaust particulate trap system, and hence had little detrimental effect over the trap system's design service interval.