Posted on 04/24/2008 5:39:14 AM PDT by Red Badger
It's beginning to look like the near-term technology for making diesels clean enough to meet 2010 emissions rules will involve urea. Or perhaps we should say, MORE urea-Mercedes alone currently offers four diesel models in North America, including the E320 sedan, that currently rely on a urea-based emissions system.
You have probably heard that urea is a way of carrying ammonia, which can be used to catalyze NOx. Selective Catalyst Reduction (SCR) systems are now being developed that use urea to generate ammonia, which in turn cuts NOx.
As the dieselization of North America progresses as predicted, there's going to be a whole lot of urea going on. These SCR systems will be used on new cars and light trucks starting with 2008 models. Which means that luxury car owners, truck drivers and soccer moms will need to fill up with urea every so often.
We wonder, where is all this urea going to come from, and how is everyone going to get it into their tanks? Will there be a urea shortage? What will happen when your Blue Tec car or SUV runs out? Does it quit on the spot?
Turns out that urea is a product already in mass production worldwide. An estimated 100 million tons are produced every year, most of which is used in fertilizer, especially water-soluble fertilizers. Urea is also used as an additive ingredient in cigarettes to enhance flavor, as a browning agent in pretzels, and in some facial cleansers and lotions. You have probably had it in your mouth already, since it is an ingredient in many tooth-whitening products. Urea is also a component of the chemicals included in ready-to-use cold compresses (first aid for sprains, etc).
Urea is a useful alternative to rock salt for melting ice on sidewalks and runways, since it does not attack steel the way salt will.
Last but not least, it is the active ingredient in AdBlue and other SCR systems. You might not think you need urea in your life, but probably, it already is.
It is produced commercially from ammonia and carbon dioxide. Large quantities of carbon dioxide are produced during the manufacture of ammonia from coal or natural gas, which allows synthesis of urea. So there is plenty of it around already, and more can easily be made.
This is a good thing, because new clean diesels are going to need it. Recently the EPA released guidelines for cars that use urea in their SCR systems. The issue was that consumers might not choose to refill their urea tanks when they emptied, undercutting the effect of the SCR and possibly damaging the system, which is supposed to last at least 120,000 miles. Manufacturers, such as Mercedes, understandably horrified at the prospect of a car that could strand its owner, lobbied the EPA to develop a regulatory guideline they could live with. Fortunately, the EPA developed a more practical way of ensuring the clean diesel systems stay clean.
First, manufacturers will be required to have an instrument panel warning light that alerts the driver to low urea supply about 1,000 miles before the tank is empty. There will also be a warning that alerts if the wrong chemicals are used in the tank.
For those drivers who continue to ignore the warnings, the EPA recommends other driver inducements, such as an electronic system that limits the number of vehicle starts once urea reaches critically low levels.
Making urea refills convenient is being addressed by companies such as Benecor of Fenton, Michigan. Benecor packages urea in totes, drums and bottles, and has recently developed a large-capacity, free-standing above-ground dispenser that could be placed in garages and gas stations on a widespread basis. Could be, come 2010, you'll be seeing a lot of these.
![](http://images.google.com/images?q=tbn:R8sR7daexSBGmM:www.ted-kyte.com/3D/Pictures/Spark%2520Plug.jpg";)
Rest In Peace, old friend, your work is finished.....
If you want ON or OFF the DIESEL ”KnOcK” LIST just FReepmail me.....
This is a fairly HIGH VOLUME ping list on some days.....
Urea gonna love this KnOcK!................
No more running out of gas on a lonely road!
Are you happy to see me or did you just fill up your urea tank?.............
How many miles per gallon of piss can I can? I’m just getting out of bed and can top off a tank if needed.
Late to the party, but it seems to me that urea is the number two ingredient in urine, I’m sure that lots of others will exploit all of the requisite jokes this involves.
“We’re running low, folks. Anybody gotta take a dump?”
Properly nitrated, urea also makes a nifty homemade explosive.
Could be a chance to help our energy situation — but the Democrats will piss it away.
http://www.weizmann.ac.il/usersfiles/ics2007/2007/abstracts/237.html
In this case, the urea is simply cleaning up the emissions (ahem) of a DIESEL engine.
You still need DIESEL for fuel.
Yeah, they know. They’re just being FReepers.......
Hey.
That's my son in his red "Pete"
Ammonia itself can be an effective way of producing hydrogen for use in fuel cells. They won’t do it because ammonia is so caustic. But I wonder if that problem would be solved by using urea to produce ammonia on an as-needed basis in a fuel cell?
How many pots of coffee will you need to 'shovel' the driveway, I wonder.
If vehicles running on fast food waste oil smell like french fries, vehicles running on urea will smell like pi..?
Yup, Urea is going to make a splash. I think it will be displaced though through improvements in combustion control, or an in situ fuel reformer like the the Honda system.
Not being a chemistry wizard, I could not tell you the do’s and don’ts of ammonia vs. urea...........
I despise the EPA.
Urea is also the key ingredient of piss.
I don’t think so. The urea is injected and immediately breaks down into something else and combines with the exhaust to help reduce the pollutants..............
Depends on how far north you live and how long your driveway is.
The #2 ingredient in #1...
OK, so you just pee in the exhaust pipe?
If you’re so inclined, go for it.
I think we’ll see the market become the deciding factor on which technology becomes the De Facto standard. In cars, the urea filter needs to be replace every 100-120k miles, and trucks (they are estimating) every 500k miles. That’s a lot of money. So, of course, some of the OEMS are on board, more parts = higher residual revenue streams.
AFAIK, Mercedes and Volvo/Mack are the only Class 8 Truck motor OEM that have firm plans on using urea.
The others are committed to using diesel particulate filters, EGR, and newer fuel management systems.
Cummins will use it on smaller vehicle motors, Class 1-5, International (Navistar) is fighting it tooth and nail, PACCAR (Peterbilt, Kenworth) have, at one point, said they will use it, and later when seeing Cat’s results without it, said they will hold their options open.
Caterpillar, in fact, already has motors in it’s test fleet that surpass the 2010 rules without using urea. It makes uses of a combination of combustion technologies, fuel system technologies, electronics and after-treatment applications, a result of their technological leadership and continuing with their ACERT program. And they get my vote for rising to the challenge and finding a creative solution that benefits all.
See, here is the problem, one that I harp on all the time....people, and especially big business and Government, seem to always take the path of least resistance, letting others innovate and make the rules for them.
Is there no creativity and “can do” spirit in our world anymore?
There is no "leadership" in our "leaders" anymore........
You’ve got that right.
“Dude, your ride smells like armpits...”
As I understand it, the Cummins 6.7L engine that started going into Dodge pickups in 2007.5 is compliant with the 2010 emmissions requirements. It uses a diesel particulate filter w/ on board regeneration and exhaust gas recirculation.
That said, there are many of these trucks on the road today that have removed all the emmissions hardware and have electronic foolers on them. With the emmissions equipment, these 3/4 ton pickps gets 12-13 MPG. With it all removed and running straight piped exhaust and a high flowing air intake, the fuel economy will go upwards of 20MPG; depending on driving habits, loads, etc.
So, is the carbon footprint of a 6.7L engine getting 12MPG less than tne same engine getting 20MPG w/20-25% greater HP? What about a 4. something liter engine that is not choked down by all this crap that produces the same HP as a 6.7L emmission controlled engine?
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