The increasing Environmental Protection Agency standards for diesel engine exhaust emissions are forcing the transit industry to find a means of cleaning up the air. A particulate trap oxidizer systemis currently accomplishing this task on two-cycle transit bus engines. At Phoenix Transit System this same technology is being applied to a Maschinenfabrik Augsburg-Nuernberg AG (MAN) four-cycle engine to demonstrate that four-cycle exhaust can also be cleaned. The particulate trap system installation in the MAN bus is summarized. The initial temperature testing was conclusive that all system components were operating within component manufacturers' specifications. Smokeopacity testing on the particulate-trap-equipped bus resulted in readings of 0 percent smoke opacity compared with a similar MAN bus with as much as 27 percent opacity. Operating data are being collected to determine if the system is applicable to a four-cycle transit bus engine in a desert environment similar to that in Phoenix, Arizona. (A)
Abstract