Generator Sets
A generator set powered by a small diesel engine can be treated in much the same way as a main propulsion engine. The most common exhaust layout is the same as for a low mounted engine, with the exhaust dropping into a waterlift silencer below the waterline, then rising above it to a swan-neck, before falling steeply away to the hull exhaust outlet.

The spluttering of a water-cooled generator in a quiet anchorage or marina can be surprisingly irritating - particularly during the night. The answer is to replace the gooseneck with a water separator that allows the water to gravitate out of the water/gas mix and be discharged silently below the waterline.

There is another problem with generator exhausts, particularly with superyachts, and that's soot. These are greasy and unburned deposits which are quite common in diesel engine exhausts. These deposits can spoil the look of valuable wooden decks and they also float on the water - forming an oily sheen on the surface, and thus covering bathers with soot and greasy deposits.

PureGen is a new device from Halyard that removes soot from generator exhausts. It operates in tandem with the generator's exhaust gas system and it can be installed in either a 'wet' or a 'dry' exhaust system. It works by passing the exhaust gas through an electric heater which intermittently cuts in to raise the temperature of the exhaust to ensure that all the soot is destroyed and burnt from the catalytically coated ceramic filter. The ceramic filter is therefore continuously cleansed by the heater element and thereby adds between 2.5mbar and 10mabr in back pressure in the exhaust system and the only maintenance required is reversing the filter every 6 months or so.
 

Exhaust Configurations

PureGen - a simple soot burner that cleanses diesel generator exhaust from greasy, dirty soot particles