We use aqueous ammonia and inject it in our scrs for NOX reduction.I can't imagine running around with a ammonia tank and fuel tank...lol would remind me way to much of being at work! Good idea for Nox at a power plant but for a car? Time will tell.Kevin

 

Wayne,

Seriously....what do you do for a living? I'm impressed by your knowledge of EPA Emissions standards and your knowledge of Tier II Bin 5 diesel cert options.

I'm glad you framed it as "relatively inexpensive". There are, from what I can tell, two key issues / impediments. The biggest is definitely the prospect of whether or not the urea canister issue will ever be approved. Even though the system can provide warnings, the EPA concern has been that the owner can still ignore the alert and continue to drive without replenishing the urea canister. If EPA doesn't allow the urea solution, we're back at invention as well as very heavy converter loads (precious metals.). That's where a lot of the incremental cost comes in.

The other issue is that it is apparently more difficult, even with a urea solution, to certify smaller displacement diesels than larger displacement engines. This means that even though we may see diesel trucks and SUVs, we may be waiting for the next generations of vehicles before we see crdible passenger car applications.

Peace,

Martin

 

Anybody know the chemical reaction that will involve urea ?

I was under the impression that emissions testing at 50K miles is mandatory, and that 120K is voluntary for Fed tier II bin 5. Not positive though. I had not heard of the 'car stops if maintanence not performed' urea canister solution, but it makes a lot of sense, as long as it can not be easily bypassed.

Comparing CARB, Euro, and US Federal Emissions standards is a pain, mostly because the US uses pollutant/distance, while Euro is pollutant/fuel.

Here are some numbers that help to figure it out. First, Euro III and IV, CARB, and Fed Tier II bin 5:


To get an idea what 2008 Euro V will require,
EURO V is the emission standard for cars that will be introduced in the EU in 2008 that limits car emissions to 2 g/kWh of NOx and 0.02 g/kWh of PM (Particle Matter).


EURO IV is the emission standard for cars that will be introduced in the EU in 2005 that limits car emissions to 3.5 g/kWh of NOx and 0.02 g/kWh of PM (Particle Matter).

These numbers are in gr/kWh, but you can apply ratios to the graph above. As you can see, Euro V Nox is still 4.5x greater than Tier II Bin 5; and since PM did not change, Euro V PM is 4x greater than Tier II Bin 5. AFAIK, PM is easier for the diesel manufacturers to clean up than Nox.

 

http://www.greencarcongress.com/2005...r_nosubxs.html

http://www.greencarcongress.com/2005...ishi_fuso.html

4NO + 4NH3 + O2 -> 4N2 + 6H2O