The urea in DEF breaks down the oxides of nitrogen (NOx). Since diesel engines burn fuel at high temperatures and pressures with the oxygen content above what's needed for stoichimteric combustion, some of the excess oxygen combines with nitrogen to form NOx. Gasolene engines typically run very close to stoichimetric and typically generate less NOx - and three way catalysts are very good at reducing the NOx and using the released oxygen to burn the unburned hydrocarbons and CO.
I do remember the urea reaction with NO2/N2O4 from my freshman chem lab.
What exactly does DEF do? I've seen it at truck stops. I assume it reduces emissions.
So who came up with the idea of peeing (urea) in the gas tank to reduce emssions?
challenger3980 BTW, it is DIESEL, not Deisal.
BTW, it is DIESEL, not Deisal.
When I was in college, a filling station (most likely in North Adams, MA, on the way from Amherst College to Williams College,) had a large billboard facing west-bound trafic, advertising the availability of "Diesle" fuel.
Buslist I remember listening to a UP locomotive guy (ex CNW if you can guess) that every locomotive fueling point would need a cattle feed lot to meet the requirement!
I remember listening to a UP locomotive guy (ex CNW if you can guess) that every locomotive fueling point would need a cattle feed lot to meet the requirement!
Shadow the Cats owner I doubt they would need that much my bosses last order of 2016's just arrived they carry 250 gallons of useable fuel and only carry 25 gallons of DEF onboard and that will last for 500 gallons of diesel fuel. So the ratio is about 20 gallons to 1 in usage. So based on EMD and GE having a 5K gallon tank your looking at a 100 gallon DEF tank when the EPA says sorry have to use it.
I doubt they would need that much my bosses last order of 2016's just arrived they carry 250 gallons of useable fuel and only carry 25 gallons of DEF onboard and that will last for 500 gallons of diesel fuel. So the ratio is about 20 gallons to 1 in usage. So based on EMD and GE having a 5K gallon tank your looking at a 100 gallon DEF tank when the EPA says sorry have to use it.
The EMD specification sheet for the F125 indicates a fuel capacity of 1800 (US) gallons and a DEF tank of 410 gallons.
The SC44 has the same fuel capacity but I have no figure for DEF.
M636C
NorthWest M636C I asked an EMD representative if they expected to offer the 1010 engine in export applications and they said that the maintenance requirements would be too high for a customer not needing to meet the Tier 4 regulations. It is really interesting that they actually admit this. I suppose it is because the railroads essentially forced them to go that direction.
M636C I asked an EMD representative if they expected to offer the 1010 engine in export applications and they said that the maintenance requirements would be too high for a customer not needing to meet the Tier 4 regulations.
It is really interesting that they actually admit this. I suppose it is because the railroads essentially forced them to go that direction.
M636CI asked an EMD representative if they expected to offer the 1010 engine in export applications and they said that the maintenance requirements would be too high for a customer not needing to meet the Tier 4 regulations.
beaulieu Neither GE nor EMD freight locomotives need DEF to meet Tier 4 emission standards. EMD passenger locomotives with Cat engines do require DEF.
Neither GE nor EMD freight locomotives need DEF to meet Tier 4 emission standards.
EMD passenger locomotives with Cat engines do require DEF.
So do the Siemens SC-44 Charger locomotives with Cummins engines and the Cummins engined freight prototype (need DEF).
The MTU 4000 was advertised as meeting Tier 4 without DEF but this may not have worked out. That engine does need DEF to meet marine IMO Tier III regulations which are similar to USA Tier 4.
Basically the (greatly modified) GEVO and the EMD 1010 are alone in trying to meet the standard without DEF and it is fairly early days to see how well these engines will last in traffic while still meeting the standard.
GE did build a prototype GEVO, more or less an ES-44 which used DEF but they followed their customer's wishes and built the ET-44.
I asked an EMD representative if they expected to offer the 1010 engine in export applications and they said that the maintenance requirements would be too high for a customer not needing to meet the Tier 4 regulations.
challenger3980 So for a pick up a 3-5 gallon DEF tank is probably adequate.
Ram 1500 Ecodiesels have 8.5 gallon DEF tanks. Popular belief is that they put a large DEF tank on it to last ~10,000 miles to line up with regular oil changes. That's the theory, anyhow.
Looks like the diesel GM colorados get a 5.5 gal tank. Same with the bigger Ram 25 & 3500s.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
CandOforprogress2 I see empty containers of DEF Fluid all over my local Deisal Station which is basicaly Urea from what I smell and read. I guess that locos are not required as of yet to use this stuff
I see empty containers of DEF Fluid all over my local Deisal Station which is basicaly Urea from what I smell and read. I guess that locos are not required as of yet to use this stuff
DEF per se is not a requirement for diesels. Vehicle manufacturers have found DEF to be the most expedient method to meet required emissions standards.
Class 1 carriers were adament in their opposition to using DEF in their locomotives. GE and finally EMD have found engineering means to meet the required standards without using DEF. Potentially, over the coming years, vehicle manufacturers will devise technology in their diesel engines that will no longer need DEF to meet the required standards.
Never too old to have a happy childhood!
BTW, it is DIESEL, not Deisal. It was about the 2010 model year that Over The Road (OTR) trucks started needing to use DEF, and that really slowed truck sales, as customers put off buying new trucks as long as they could to avoid the DEF headaches. Now most truck stops have bulk DEF at the pumps, but at first it was a real pita trying to find it. Some one buying DEF in 1-2.5 gallon jugs is wasting a lot of money, the 2.5 gallon jugs tend to retail for $14.99 out here in the PNW, with bulk at the pump averaging about $2.69/gallon.
The railroads have gone to great lenghts to avoid DEF, or other supplementary additives, but it is likely just a matter of time before they have to accept it, Even new Diesel pick ups are using it, and are likely the customers buying it in jugs. I don't know what size the DEF tanks are on pick ups, but the 10 gallon tank on my Peterbilt 384, is a bit on the small side, and generally is good for about 2,000 miles. So for a pick up a 3-5 gallon DEF tank is probably adequate. With the smaller capacity it probably isn't worthwhile to go to the commercial fuel islands to get DEF, when a 2.5 gallon jug will last a pick up driver much longer than in a tractor trailer, and at that point saving a couple bucks just isn't worth the hassle.
Doug
May your flanges always stay BETWEEN the rails
Good! I stand corrected, and I learned something!
Some do, some don't. From what I've read GE locomotives use urea for emission reduction, as of this time EMC (Caterpillar) locomotives don't.
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