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dieselrealtor
05-11-2004, 15:30
I heard something on the radio about them mandating a "clean diesel", removing the sulphur & adding cats.

Does anyone know more about this, is it something that will drive the price of diesel up or affect the runability of the older units?

Thanks

Kidd
05-11-2004, 16:44
A clean diesel will cost more, the engine manufacturers are spending millions to meet the new standards, guess who will pay? The fuel will cost more, that's a given. :(
K.D.

Reid
05-12-2004, 13:21
Just a thought, but isn't the sulfur in diesel responsible for the lubricating qualities that help diesel engines last so ling?

CaseyR
05-12-2004, 17:27
One article I read said that sulfur itself is not a lubricant but that in removing the sulfur some earlier processes also removed some of the lubricating fractions of the diesel fuel.

Another article says the following:
"It's not the sulfur itself in diesel fuel that provides the benefits. In fact, high levels of sulfur when mixed in the combustion process form sulfuric acid, which can be highly corrosive to many internal engine and exhaust parts. But the diesel oil with the highest cetane level and and best lubrication qualities unfortunately comes with sulfur as a byproduct." http://www.sailnet.com/collections/articles/index.cfm?articleid=woodto044

Some other articles say the real problem is that there is no lubricity standards for diesel fuel and are pushing for the adoption of such standards.

One article said that Cummins said the low sulfur fuel is not a problem and recommends against using additives.

damork
05-12-2004, 18:00
I've worked in fuel systems design and know some veterans of the business. Some systems don't rely so heavily on the lubricity as others, those where part of the pump is lubed by engine oil. However, pumps like those relying solely on fuel lubricity could have problems. Systems designed in the era of lubricated fuel need some rethinking to run on "dry" fuel.

I understand Europeans already have refined fuel to very low levels of sulfur or even removed it in some cases. I don't know what they are doing, possibly adding a lubricity agent. Ceramics can help, but in the long run I suspect refineries will have to provide lubricity additives.

I worked 3 years in the Artic on diesels and we had problems with sticking injectors in Detroit Diesels as the fuel there was highly refined to remove all waxes. We added engine oil from time to time, but still had problems. Cat 3208 pumps had problems as well - seemed their plunger and barrels were sticking due to lack of lube. The fuel was perfectly clear - looked just like water, it even felt dry like a cleaning solvent.

CleviteKid
05-13-2004, 04:56
An alternative to tetrachloroethylene (a.k.a. Perchloroethylene, or PERC) is Stoddard solvent, essentially a highly refined, water-white hydrocarbon with a flash point above 140F, essentially ultra-pure diesel fuel. About 10% of the drycleaning plants in the U.S. use Stoddard solvent to avoid the very expensive contamination of soil and groundwater by PERC. The customers don't know the difference, they just want their clothes to come back clean.

Dr. Lee :cool:

PS: How do I know this? Because I consult for dry cleaning equipment manufacturers accused of contributing to underground contamination, and also for municipalities trying to find the real culprits responsible for useless water wells. A lot of this is going on in California's Central Valley. :eek:

Peter J. Bierman
05-15-2004, 06:15
As stated before, over here in Europe we have low sulfur or non sulfur fuel and run a lot of diesels.
Like 40% off all cars sold are diesels, common rail systems most off them.
What is more important for those engines is clean fuel, the CDI's, TDI's, CTTD's and TDG's as they are called, are extremly sensitive for dirt and water in their fuel.
As for the american diesels like the 6.2 and 6.5 and Cummins, I do not know off pump failures coused by low sufur fuel.
I used to run the mill.spec pump whitch is bullet proof but a buddy had a 6.5 TD and only had the "normal" DS4 pump failure at 80 K miles.

If it was a problem, the gas stations would be loaded with additives but they are not!
So I guess there is not realy anything to worry about.

Peter

tom.mcinerney
05-15-2004, 18:53
The Bush administration is moving forward with the plan to mandate cleaner diesel fuel in USA beginning, i think 2007. Sulfur content will drop from ca 400ppm to ca 30ppm. Less residue (sulfates, sulfuric acid) in exhaust will allow much lower emmissions . New catalytic converters are capable of curbing upwards of 60% of the hydrocarbons, particulate matter, and carbon monoxide in non-egr vehicle engines. <http://www.epa.gov/otaq/retrofit/retroverifiedlist.htm>.
I think the high sulfur fuel currently allowed in off-road/construction equipments will be phased out; the new engines for those services are being redesigned for emmissions more in line with automotive applications.
The latest electronic injection controls, and EGR, can lower peak pressures in the cylinders, moderating nitrous oxide formation.
The EPA recently estimated the retail price of our diesel fuel would rise $.08/gal(US) to cover the added refining costs. Unlike much mideastern crude oil, most of that remaining in the Americas is high-sulfur stock.