SCR Isn't So Simple

[DriVer]

YouTube - SCR isn't so simple!

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Navistar, MaxxForce & Monaco RV LCC would like to share their vision for the future of diesel emissions by presenting the Preserve Our Freedoms website.

[spike45]

Perhaps you do not know that International Maxxforce engines do not use SCR and that Navistar International engines do not meet the 2010 EPA requirements. So, they sue the EPA to stall for time. SCR really is simple; spray 32.5% urea solution into the exhaust stream ahead of the catalyst muffler. The urea at those temps changes into ammonia that reacts with NOx. Cleaner exhaust and less EGR. Navistar is trying to do what Caterpillar could not do with their ACERT, twin turbos engines. In fact, the Maxxforce 15 is a Caterpillar long block with an MAN air and exhaust system that closely resembles the ACERT. MAN is now owned by Caterpillar.

Don't rush out to buy a Maxxforce. A field test model operating with a customer that I work with on some coolant field testing has their new ProStar with Maxxforce in the shop more than on the road. That truck has its own factory engineer to babysit it!

[DriVer]

Quote:

Originally Posted by spike45 So, they sue the EPA to stall for time. SCR really is simple; spray 32.5% urea solution into the exhaust stream ahead of the catalyst muffler.

Spike45, Greetings! You lost me ... did you know that an SCR equipped vehicle or any other 2010 Emission compliant vehicle does not have a muffler?

[spike45]

Remove that diesel oxidation catalyst unit and get back to me on how much louder the engine is.

[DriVer]

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What others are saying about SCR

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(Look for the top right tiangle fold over)

[spike45]

You say "po-tay-toe"

I say "po-taa-toe"



They taste the same, look the same, do the same. Remove one and the engine is much louder. Cummins has referred to them as Diesel Oxidation Catalyst and as Catalyst Reduction Muffler. Guess it just depends on when we get into the conversation.

Cheers,
Gary Spires
Sr. Field Service Engineer
Fleetguard / Cummins

[dbear]

spike45, is there a reason you seem to be looking for a fight? DriVer has never implied AEGR is fully compliant. In fact, he's stated many times that despite making great gains, they still have a huge ways to go to make TIER 4. Same also applies to SCR, except I've never seen the SCR guys admit it as openly Navistar has, nor have they ever tried to hide the fact they have been using credits to meet compliance since TIER 3(?), just as SCR has.

The main component of the lawsuit Navistar brought was centered around the fact that the EPA did NOT order the SCR guys to derate their engines via computer controls in the event they run out of DEF. In effect, this meant these engines could be operated outside of the law, and without any reduction in pollutant levels. With this in mind, AEGR seems a better choice from an environmental standpoint.

I don't understand why this SCR vs AEGR is so adversarial. It seems polarized worse than the whole Ford vs CM vs Dodge thing. Where's the harm in pursuing different technologies, unless you're heavily invested in DEF manufacturing?

[powerboatr]

Quote:

Originally Posted by dbear I don't understand why this SCR vs AEGR is so adversarial. It seems polarized worse than the whole Ford vs CM vs Dodge thing. Where's the harm in pursuing different technologies, unless you're heavily invested in DEF manufacturing?

exactly ....
heaven forbid someone do something different , there is always more than one way to skin a fish....or cat

[spike45]

Quote:

Originally Posted by DriVer YouTube - SCR isn't so simple! · Navistar, MaxxForce & Monaco RV LCC would like to share their vision for the future of diesel emissions by presenting the Preserve Our Freedoms website.

DriVer, you may find this article interesting in regards to Cummins view about noise abatement available from an SCR system.

http://http://www.dieselprogress.com/Industry-News/3329/@OTC:-Cummins-Reveals-New-Engines-Facility/

The third paragraph down discusses the topic of replacing a muffler on previous industrial engines with an SCR system that has similar ability to provide similar sound suppression.

Terminology is obviously different from differing engine manufacturers.

[DriVer]

Quote:

Originally Posted by spike45 Terminology is obviously different from differing engine manufacturers.

√ Understood. All that plumbing does attenuate noise that's for sure. We'll be missing those good old days when you could just go and get an off the shelf Maremount and stick in on the tail pipe!

[Ray,IN]

I miss those days too Mike. And today there is a possible $10,000 fine and 10 years in jail for modifying the exhaust system. Todays exhaust system is very complex, has to be to meet EPA rules.
What I don't get is European air quality rules are more stringent that ours, yet they don't appear to have these issues. I hope Navistar gets it things worked out.

[RustyJC]

European regulations target greenhouse gases, especially CO2 where the diesel has an advantage over gas engines. The U.S. regulations target smog precursors (NOx) and particulates, where the diesel operates at a disadvantage.

Rusty

[DriVer]

Quote:

Originally Posted by RustyJC European regulations target greenhouse gases, especially CO2 where the diesel has an advantage over gas engines. The U.S. regulations target smog precursors (NOx) and particulates, where the diesel operates at a disadvantage.

Rusty, Thanks for putting that in focus for us.

[two-niner]

Think of it this way. Everything is driven by CARB in the LA basin.

Once their perimeters are met, they tighten them some more.

In an interview with the CARB chief the question was asked "So that means standards will never be met?". His answer "That is correct"..... That is the rest of the story. The article was in Science Magazine several years ago.

Kerry