Pilot-scale experiments of continuous regeneration of ceramic particulate filter in marine diesel engine using nonthermal plasma-induced radicals

As the regulations governing diesel engine emissions become more stringent, it is difficult to fulfill these new requirements using only techniques that improve combustion. More effective aftertreatment technology is thus needed particularly for particulate matter (PM). Although the use of ceramic diesel particulate filters (DPF) is a leading technology in automobiles, it still presents a problem in terms of soot removal or regeneration for marine diesel engine operated with marine diesel oil (A-heavy fuel oil) including the sulfur. In the present study, to establish a nonthermal plasma DPF regeneration method for marine diesel engines, laboratory-scale and pilot-scale experiments are carried out. The pressure difference decreased only when the plasma is turned on and that regeneration is realized at 320°C. The amount of ozone required for regeneration is determined under various engine-operating conditions, and basic characteristics of regeneration are clarified. The required plasma energy is approximately 5% of the generated power of the marine engine.