High Sulphur Diesel

Try carrying out an independent analysis. 10,000 ppm (a.k.a. 1%!) seems rather high. One might not expect most of the exhaust system components and the area surrounding the exhaust aperture to last very long at those levels.

10,000 ppm is well beyond responsible content.

see this link:

http://www.dieselnet.com/standards/us/fuel.php

we're running15ppmw for on highway use now.

milo

Ask your engine supplier for a fuel spec. Generally, 1/2 of 1 % (0.5%) is OK, but it depends on counter measures deigned into that engine.

Now for those PhD chemists out there, don't pick this apart. It is a true statement in a practical sense.

Here is what happens when you burn 'sulfur' in a diesel engine, especially a large engine with high/ low temperatures swings.

The reaction of burning sulfur with air's constituents of oxygen and nitrogen produces sulfur tri-oxide. SO3. Then when you shut off the engine, moisture in the air present inside the crankcase condenses to water and lands in the oil pan. H2O. When mixed wit water, the NO3 become H2SO4. Sulphuric acid. This eats chrome off of the rings, babbitt off bearings and forms cold and hot corrosion in the engine slowly eating it away from the inside. High calcium lube oils try to suck up the acid, but too much calcium in the lube oil can cause little hard balls when it is burned as well. Bad situation all the way around.

If you have high sulfur, run your engine very very hot and hence keep the SO3 in the form of a vapor to get it out of the engine. Use extraction blowers to gently suck out the crankcase fumes. Keep the breathers from condensing fumes and sliding back down inside the engine. Put a drip leg in the breather pipe to prevent this. If you keep the engine cooling water liquid, it will cool the engine. Use pressure and chemicals to keep the cooling water liquid but run the engine VERY hot. Modern engines run above 105*C water and sometimes up to 121*C. The goal is to NOT allow the water to flash to steam since gas entrained liquids are poor coolants.

Engine suppliers use temperature control in the engine and special materials to fight sulphuric acid cold and hot corrosion.

Summary:

* Carefully choose lube oil for high sulfur

* Run engines very hot; keeping the water liquid somehow

* Keep condensation to a minimum somehow

* Get the normal combustion gas fumes out of the crankcase and keep them out

* Do not idle your engine at low load (truck or lorry drivers that do this while they eat lunch are destroying their engines)

Hope this helps . . . . .

Hi Petro Power- is sulphur in diesel an extreme pressure lubricant?. I know a guy who uses used chip fat/oil to run a diesel truck- it is heated by water coils from radiator in a tank- prob is injector pumps only last 2,000 kms- recondition costs $2,500, new pump $10,000- after 3 rebuilds, he is going back to straight diesel!. The rebuilders say that bio-diesel causes same probs- I read somewhere that lack of sulphur was the prob- but my feeling is that the higher temp chip/fat/oil causes excess wear as against cool diesel- I spoke to a guy who makes his own biodiesel from chip/fat/oil- it costs him 50c/litre(as against pump price of diesel $1.60litre)- he has done 20,000 kms- no worries- the conversion means no heating is needed.

Some rubbers used in older diesel engines as seals are attacked by various "Bio" diesels....Rape oil Diesel being the worst, but all Diesels made from plants (recently that is!) seem to have this problem.

He needs an engine that has either had every seal replaced with modern Bio safe ones, or was built to accept "Bio" Diesel in the first place....

The second Guy you mentioned seems to have achieved that well.

VW changed all its sealing materials to allow Bio about 7 years ago, but subsidiary heating units that they bought in did not! So if you had the extra heating unit, you were STILL not allowed to use Bio Diesel!!! Stupid if you ask me!!!

I'm not sure if sulfur is a high pressure lubricant or not. I'm too dumb on that. But I do know about injection pumps and nozzles. The injection pump is a metal to metal fit "pump" that has a stroke length. Fuel is trapped and the stroke compresses the liquid to high pressure. On cars it might be 800-1000 barg (11,600 - 14,500 psig) and on large engine that I play with it is 2000 barg (30,000 psig). The tolerance of this plunger and barrel pump is in microns. They are precision ground and they are stroking up and down like a piston engine, metal to metal. So fuel viscosity is paramount. Below 0.5 cSt at the plunger and there is not enough lubricity. Above 15-25 cSt (cold) and the tips will be blown off of the injection nozzles (trying to force jelly through tiny holes). So, perfect viscosity at the injection plunger and nozzle tips is about 1-5 cSt ideally.

My daughter runs free French fry oil in a Ford Excursion Power Stroke Diesel and a Mercedes sedan diesel for 2 years now with absolutely no problems, but, she maintains correct viscosity by a control valve on the tank heater to throttle water in a shunt circuit and not overheat it. Also, water is a likely culprit on your friend's system. This oil is full of water and if your friend has a large tank running hot and on empty a lot, water from the atmosphere will condense at night. Water kills injection plungers slowly (lubricity issues and emulsification).

My daughter's final filter is 0.3 micron coalescing filter. She has a suction strainer to keep out dogs and cats, 250 mesh inline for fine particles, 5 micron paper and final 0.3 coalescing paper filter. She sucks oil out of restaurant vats, brings it home to buffer in a 1000 liter tank (water and sediment), then taps off the top with a floating strainer pickup and goes to another clean oil tank and constantly 'polishes' the fuel in a loop with a filter bank equal to the on she has on the truck. The oil looks better than store purchase vegetable oil. Pure light golden color. She did all this work herself while her Marine Sargent husband watched on ! Installing the kits to both cars as well with some modifications from "Dad's " spec.

Ain't it a joy?

milo

Good post. Except for the misplaced NO3 in the 4th para, which I know you meant SO3, that is essentially correct. I would suspect that there would be a lot of dead vegetation in a large area around that generator installation! Someone with more experience can comment, but it's possible that running the diesel fuel thru a mixed ethanolamine countercurrent stream or bath might reduce or remove the sulfur in the fuel. How to separate the fuel from the ethanolamines would be a problem.

As I understand it the removal of sulphur from automotive distillate once you get to 0,5% becomes a fairly expensive proposition, both in equipment and production.

This is going to really hurt the Maritme Industry and of course every individual on a global scale. I think that by 2010 the fuel ships burn within 200 nautical miles of land has to be < 0.1%...............this is going to cause transportation costs to inflate rather rapidly.

On RN ships in the 60's, you could clearly smell the sulphur in the exhaust gases.....God knows what percentages were in use then!!!

Same,same RAN ships......................when serving on the aircraft carrier HMAS Melbourne, one of the valves that had to be opened when flying, was steam to the catapult. This valve was next to the funnel uptakes at the top of the machinery space..............you couldn't breathe their, with the sulphur fumes and heat. It used to take 5-10 minutes to open the valve. There was a small crack in the uptakes that admitted sufficient funnel gases in to make life very uncomfortable.

There was a fan not too far away. You would stand under the fan..........take a deep breath, climb up a short ladder and try to start opening the valve................before you took your next breath you had to be under the small fan outlet for a minute or two, then away you would go again, until the valve was open.

Those were the good old days Andy.

I still miss them, exercising off Australia with the RAN Melbourne and other ships.....Good runs ashore too!!!

You are right there chief..................there was nothing like a good pissy run ashore.

Had some beauties in Singapore, in the NAFFIE Club opposite Raffles. You RNers were really bad news..............mad as cut snakes.

....or worse!!!!

I still remember Singapore as it was, when Raffles was one of the tallest buildings around!!! The foundations for the Singapore Hilton had just been laid!!!!Slightly different today.......!

What about Bugis Street Andy................one had to be careful when one had had a few too many ales

Has the "one" in the short dress got hairy legs???????

I believe that's all changed ..........large shopping centre.

Did you ever get to Olongapo, the city outside of of the Naval base at Subic Bay.

Bugis street was dangerous, I have drunk beer there a few times, the saying on the street was "If she is ugly, its probably a she, but if she is beautiful, its a he!"

Yes I was in Subic bay on HMS Devonshire, while in port we had a bad fire under the missile compartment. It was funny, all the RN personnel running to the ship to get the fire out and all the US sailors running for their lives in the opposite direction!!! I could hardly run for laughing!!!

We put it out and moved all the missiles away from the hot spot......there is a small deck of a few inches between the missiles and what is underneath and this can be quickly flooded if needed to keep things cool....

The town next to the dockyard was like the wild west - check your guns at the entrance before being allowed to drink!!

An RN colleague (much the worse for wear after a heavy evening on whisky) refused to pay his bar bill, the barman pulled out a huge sixshooter, cocked it and fired a bullet into the ceiling near the aforesaid colleague's ear, he paid immediately, was stone cold sober and stone deaf in one ear for several days!!!! Irishmen!!!! When will they learn....the barman was 3 x his weight and size too......!!!

The same guy got knocked out a year or so later because he got drunk and obnoxious at another colleague's wedding, by the Bride's Mother!!!! He never lived that down either......she was smaller, but heavier, meaner and sober!!!

Sorry for typo. NO3 v SO3. The idea is the end product that kills your engine is DEFINATELY H2SO4. And is begins by burning high sulfur and it combines with condensed water. Hot engines keep the water condensation as a vapor and keep the burned constituents as a vapor and we want to extract those things OUT of the engine via the breathers and keep them out. The remaining H2SO4 is sucked up by chemicals in the lube oil, but too heavy of a dose of those chemicals causes problems also.

Cheers

Hot engines keep the water condensation as a vapor and keep the burned constituents as a vapor

This maybe okay in high speed diesels...............not so in low speed diesel engines.

In the mid 70's when oil companies were doing it hard for a dollar (sic), among other things they put catalytic crackers into the refining process...........more product from same volume of fuel.............extremely poor quality bunkers. In high sulphur content bunkers (up to 6% in some cases), engines had problems with low temperature corrosion. SO₂ and SO₃ combining with water vapour and forming sulfurous and sulphuric acids respectively, which caused major engine problems caused by "low temperature corrosion.

Engine manufacturers said easy...........raise all engine operating temperatures for your above said reasons. However bunkers contained small traces of vanadium, sodium and iron.............pow...........high temperature corrosion. This was worse and more damaging than the low temperature corrosion and the high temperature corrosion could not be easily overcome.

After a couple of years head scratching.............the answer...............dropping engine running temperatures to normal and injecting a high TBN(Total Base Number = high alkalinity) oil into the upper cylinder each stroke to neutralise the acids formed by combustion.

Notice I didn't mention vanadium which is a hot temperature plating mechanism (if memory serves around 1000*F ?) that keeps exhaust valves from closing. I specialise in large bore engines burning crude oil as fuel (Wartsila, MANN, MaK, etc) and to combat sulfur, we use high crankcase temps, to combat vanadium we use valve rotators and special valve materials and grind angles with VERY aggressively cooled exhaust valve seats, high duration closing and high overlap timing to promote heat transfer. If the valve seats don't get above the plating temp, vanadium doesn't plate out and burn a valve. Cold temp corrosion can dribble down the intake valve stems and score them . . . bla bla bla bla. in low loads, I heat the charge oil. In high loads, I coll the charge air. It is all about process temp control at strategic points inside the engine. I have 25 internal design tricks to large bore slow speed engines to burn crude oil. Large to me is 10 MW and speeds down to 450 RPM. I have no two stroke ship engine experience, such as the Sulzer RTA 96 (Wartsila).

Cheers

I have no two stroke ship engine experience, such as the Sulzer RTA 96 (Wartsila).

Thems the ones I was talking about, anywhere from about 95rpm-200rpm, all two stroke.

to combat vanadium we use......... special valve materials

Just a question out of interest on this point, do you use stelite on valve faces and valve stems (ends). I have found it successful on medium speed engines using blended residual fuel.

Certainly interesting stuff when you get into larger diesel engines.

Good talking to you PetroPower.........perhaps that should read DiesoPower

Many years ago (in the 60's), 1,5% sulphur was about the norm for top grade diesel fuel for high speed diesels. Medium and slow speed engines could use lower grade fuels some bunkers, for low speed marine diesels, being as high as 6%.

As I understand it dropping the sulphur content in top grade distillate in Australia has been on the downward march for years. By the 70's South Australia dropped it to 0,5%, the Eastern States followed later. Sulphur levels were continuing to drop until they reached 0,05%, On January 1 2006, it became mandatory for ULSD (ultra low diesel fuel) with a sulphur content of 0.005% to be used and by 2009 it is hoped that this falls to 0.001% sulphur. As we can see some countries are a long way off from achieving these levels.

This of course does not apply in the international marine area, however the MARPOL 73/78 Convention introduce another Annex, Annex VI in May 2006. This annex covers air pollution from ships in specified areas, where when in those areas must burn bunkers containing < 1.5% sulphur. This annex covers ozone depleting substances, nitrous oxides, sulphur oxides, VOCs and ships incinerators.

Could it be that the person who gave the 10,000 ppm made a mistake, that level of sulphur seems to me to be far higher that it ever was......but of course I could be wrong and it is really so bad.....

1% sulphur content in this day and age for high speed diesel engines, is to my mind, definitely unacceptable................so is the use of CFC refrigerants.............but they are still used by the truckload in many countries!