Diesel RVs: [diesel_mercedes] diesel why the cost, don't blame the tree huggers tho,, Ca. started all this with CARB

Doug,

As a thirty year veteran of being a refinery rat I must make a couple of points, here.

The "hydrotreating" process is essentially the SAME for naphtha stocks, kerosene, and Diesel fuels. This is accomplished by heating the stocks (at relatively lower temperatures), and passing through a cobalt (sic) based catalyst in the presence of hydrogen to convert and remove the sulfur compounds. My point here is that ALL of these components must be hydrotreated in order to render them useful as fuels.

In order to make blend stocks for gasoline naphtha, and all other components, must first be separated from the crude oil charge stock, sulfur compounds removed by hydrotreating, and then reprocessed in a "reformer" type of refining process into a more suitable material of a higher "octane" number. This process uses MUCH higher temperatures and, usually, a platinum catalyst. Therefore, manufacturing "gasoline" is a much more costly process than manufacturing Diesel fuels as the Diesel is "straight run" from the crude still and simply hydrotreated while gasoline must be further processed after hydrotreating.

Also, as you know, the sulfur compounds that remained in the Diesel fuels added lubricity to the fuel which is now largely gone due to the lower sulfur specs. That is why many add ATF, MMO, or other light oils to today's Diesel fuels in order to lubricate the injector pump internals. Tolerances in these pumps are insanely small and it does not take much lubrication starvation to trash one fairly quickly.

I will agree that the sulfur mountains are a nuisance but that is the "cost" of being "green". It is a storage expense, only, for the most part. As for the fuel costs, Diesel should STILL be cheaper than gasoline and the disparity in prices occurred BEFORE the ULSD standard came along! Truth is, big oil knows that truckers use LOTS of fuel, must have it to move, and there is an increasing number of Diesel powered commuter vehicles being produced, so they want a BIG(est) slice of the "pie". Commodity traders are raking in their hogs share as well in crude stocks AND finished product prices! In a word, WE are being ripped off by ALL of them!

There are answers to ALL of these "questions" and one must look no further than big oil AND government regulations to find ALL the answers.

Mark

On 11/2/2011 5:29 AM, Doug wrote:

Here is a large part of the answer as too why Diesel Fuel is so much more expensive than gasoline,, we have small mountains of sulfur along the ship channel here in Houston area, as per the EPA, they have to refine almost all the sulfur from the Diesel fuel, too make ultra low sulfur fuels,,thats very expensive, an then someone has too store all that huge amount of sulfur, thats very expensive, too much of it, an nothing its good for either. So, NOW we pay at the pump.

Back in the good old days of cheap Diesel fuel, all that sulfur went out the tailpipe as pollution, an eventually acid rain an such,,, you guys from California should remember, an know that clean air costs us all money,, ya do remember CARB right, well its all over Texas too now, we pay about 50 cents a gallon of Diesel for cleaner air, which is rare around Houston..

My concern, being a long time Diesel Tech /Instructor, is what is the long term effect upon my darling 300d s fuel system, an pistons, maybe valves. Will my like new running engine still last forever with the ultra low sulfur or not,, thats a good question.

So bottom line, now we are having too pay a lot extra for the ultra low sulfur Diesel fuel, is it worth the cost, in cancer rate, an are we loosing part of the energy in the fuel at the same time. Our exhaust systems should last longer, without all the sulfuric acid coming thu.

   Lots of unanswered questions other than the premium cost we are having to pay at the pump. I do not think there are answers to many of the questions, but one thing for sure, our Mercedes engines were designed to run on Diesel fuel that contained mucho sulfur, a type fuel no longer available, except in maybe Mexico.

     Anyone want about a million tons of raw sulfur, Texas will sell it to you CHEAP, almost free, come get the stuff, makes an ugly mountain here in Texas. Plus it stinks like someone eating too much bean dip.

     Doug Traylor   300d daily driver, 300SD carport parts queen w/ wunderbar turbo engine.