New Flow-Through Trap System Targeting 50% PM Removal for Diesel Emission Control

A diesel particulate Flow Through Trap (FTT) system, composed of either silicon carbide (SiC) ceramic foam or stainless steel foam, has been developed and evaluated. The basic concept of the system is to configure several different pore sizes of the foam filters gradually, from large pore sizes to small pore sizes, in order to achieve high efficiency of diesel PM reduction and simultaneously low pressure drop. Each component of the FTT system was coated with Sud-Chemie's proprietary catalyst support and further catalyzed with platinum for better performance. Multiple configurations of the FTT system were evaluated by varying pore sizes (20∼50 PPI), substrate sizes, and the number of beds. Tests were conducted using 0.74 Liter and 1.86 Liter diesel engine / generator sets.

Based on the results of these engine tests, the FTT is found to be an effective device to remove more than 50% of PM from the diesel engine exhaust. The Balance Point Temperature of the FTT systems was around 260°C, and the FTT prototypes can be regenerated successfully without any further active regeneration control when the exhaust gas temperature is maintained at 280°C and higher. For the system tested in this paper, the size should be bigger than 1.3 times of engine displacement to meet the target, 50% of PM removal efficiency.