CEwriter
04-17-2007, 10:09 PM
This story from Fleet Owner http://fleetowner.com/equipment/news/epa_warms_to_scr_solution/ indicates that "EPA has reconsidered its stance against selective catalytic reduction (SCR) as a viabletechnology for on-highway diesel engines to meet stringent 2010 emissions standards, and sent a letter to manufacturers outlining its intent to certify SCR engines.
"EPA had previously resisted the certification of SCR-equipped vehicles because the system relies heavily on the end user filling “a second tank” of urea regularly. Just as fuel is consumed to keep an engine running, urea is consumed to produce the emissions benefits of SCR. Additionally, EPA was concerned about developing a sufficient national infrastructure to provide end users a convenient supply of urea or ammonia."
I understand that SCR is used in European heavy trucks and urea is widely available. Interesting stuff. 2010 is not far away . . .
"EPA had previously resisted the certification of SCR-equipped vehicles because the system relies heavily on the end user filling “a second tank” of urea regularly. Just as fuel is consumed to keep an engine running, urea is consumed to produce the emissions benefits of SCR. Additionally, EPA was concerned about developing a sufficient national infrastructure to provide end users a convenient supply of urea or ammonia."
I understand that SCR is used in European heavy trucks and urea is widely available. Interesting stuff. 2010 is not far away . . .