In this study, the authors investigated particulate matter (PM) collection efficiency of an electrostatic-cyclone precipitator (ESP-cyclone) by conducting bench tests and onboard measurements of PM emissions with three diesel engines. A small sized high-speed 4-Stroke diesel was used for a bench test and two types of low-speed 2-Stroke marine diesels were utilized for another bench test and onboard PM measurements aboard a ship of 2,703 gross-tonnage. In order to study PM collection efficiency of the ESP-cyclone, PM concentrations in exhaust gas were measured upstream and downstream of the ESP-cyclone with a partial flow dilution tunnel system. Experimental results showed that the PM collection efficiency was as high as 60-80% with the ESP-cyclone collecting not only insoluble organic fraction (ISF), but also soluble organic fraction (SOF). The ESP-cyclone realizes stable PM reduction from the diesel engine on the actual ship.
