Bunker oil?

[BioHazard]

Something I've been curious about lately is the "bunker oil" used to power diesel engines in ships. There doesn't seem to be a whole lot of info about it, other than #6 bunker is the most common in shipping, has more BTU/gallon than diesel, needs to be heated to be burned, and I'm guessing it is cheaper.

The questions in my mind are,
Is it possible for me to buy bunker oil without owning a large ocean going vessel?
Is it possible to run bunker oil in a normal diesel engine like WMO?
Would it burn like WMO without the ash from the additives?

[LowGear]

My understanding of electricity production in Hawaii is mostly bunker oil based.  I've been lead to believe that the power plants in this state are the only in the country that are licensed to burn this "nasty" stuff.  My Witte generator only reads "No Crude" under fuel recommendations.

Casey

[BioHazard]

Interesting. Is that with piston engines or just burning it to generate steam?

[LowGear]

I'll check with HELCO in the near future and report back.  Any ship experts may jump in.

Casey

[mike90045]

I thought Bunker Oil was soft roofing tar.

[Ronmar]

Yep, bunkers or heavy fuel oil.  Pretty much paste at room temp.  Ships that use it have a whole boiler system and heat pipe network to turn the paste in the tanks into pumpable/injectable liquid.  The only system I have ever been around had a diesel fired boiler to melt the bunkers.  Once the mains were lit off, engine heat provided the melting energy...  A byproduct of normal refining with little other use(too thin to tar roofs, too thick to pour without added heat), so a less expensive fuel for shipping...

[Lloyd]

And very dirty when burning.

It's now outlawed in many Ports, so Now those ships have dual fuel so they can stay in compliance while in port. In the Puget Sound Basin they have to stop burning bunker as soon as they hit the entrance to Juan De Fucia.

Lloyd

Yep, bunkers or heavy fuel oil.  Pretty much paste at room temp.  Ships that use it have a whole boiler system and heat pipe network to turn the paste in the tanks into pumpable/injectable liquid.  The only system I have ever been around had a diesel fired boiler to melt the bunkers.  Once the mains were lit off, engine heat provided the melting energy...  A byproduct of normal refining with little other use(too thin to tar roofs, too thick to pour without added heat), so a less expensive fuel for shipping...

[BioHazard]

So basically "virgin" WMO? It may be dirty but it can't be as bad for the environment as my 2 stroke boat that dumps raw gasoline into the river. Is there something special about ship engines that allow them to burn this stuff...other than the heaters? Do they have to do anything to mitigate wear or lots of internal engine cleaning? I'm guessing they rack up some pretty high run times....

I'm thinking a listeroid may love the stuff...if it is possible to source....

[rcavictim]

There was a time when my friends called me Bunker Bob.    I used bunker-C in a DIY waste oil burning furnace to heat a decommisioned cold war defence troposcatter site control building on the shore of the Great Slave lake in Canada's western arctic  for three bitterly cold, windblown winters.  My furnace took two years to perfect but operation the last winter I was there was perfect.  There was no visible particulate or carbon soot in the exhaust smoke.  You could absolutely not tell by looking at the chimney if it was operating or not.   Part of the learning curve involved a 'drip in a cast iron pan' type burner the first winter.  This revealed hard rock like mineral deposits that almost needed a sledgehammer to remove daily in what was a daily shutdown routine.  There was so much of this hard rock buildup that I could not miss a day's cleaning cycle.

From my experience I can say that I would be happy to use the stuff again to heat my buildings from a centralized boiler if I had a low cost source for the stuff but I would in no-way ask a injection pump or injector nozzle on a diesel engine to deal with it even after sufficient thinning heat was applied.  I'll bet you would get so much rock like crud jamming up the rings and valves that you would destroy the engine in a day.   I found the only clean way to burn this stuff was heat the crap out of it, create a microglobule fine sprayed mist constantly ignited by a conventional oil furnace ignition xfmer igniter system, properly and generously applied forced combustion air and very important, not to allow the resultant flame to touch any physical surfaces.   Wherever the flame touches will grow a cone of stone.  My final furnace design ran 24/7 without shutdown and never needed cleaning.

[deeiche]

rm /

[cognos]

Bunker! God help the engine that gets fed bunker as fuel!

As much as I hate to recommend Wikipedia for anything, I've had a look at this page - http://en.wikipedia.org/wiki/Fuel_oil - and find it to be "mostly" correct. This should more-or-less explain the differences in the various "fuel oils".

Bunker, at the refinery, refers to ship fuel. Fuel burned in ships. Could be any kind of fuel burned in a ship, but most likely refers to a heavy fuel oil, burned in a boiler to make steam to turn a turbine or other type of steam engine.

Bunker, particularly 6C, is nasty stuff, the Wiki page does not do justice to it's true nastiness...   It contains all matter of metals, salts, particulates, coke, water, acid, caustic, dirt, etc. that will pass through the large nozzle of a large high-pressure burner in a large boiler. There's specs on this stuff for maximum amounts, but boilers aren't too picky... and many bunkers are only burned in International waters - they may not be allowed anywhere else for environmental reasons. For this reason, many large ships can feed their boilers clean fuel from separate tanks close to shore, and switch to the BSFH (Black S#!t From Hell) when they are out to sea.

The primary thing that will eat your pride and joy in bunker is catalyst fines left over, and captured in the bunker - from Fluid Catalytic Cracking of oil in the refinery. Cat cracker catalyst is a fine powder of aluminum silicate, like fine beach sand, that has been sintered and each granule looks like a tiny sponge. A small handfull of this catalyst has the surface area of a standard football field. After it's been sintered, trace metals are introduced to give the catalyst the desired cracking characteristics.

Now - up to 2.0% spent cat is resident in bunker. How do you think all the spinny, shiny, smooth, close-tolerance parts of your diesel will enjoy a diet of some of the most abrasive particles known to humans? Along with metals, acids, caustics, water, solid coke, soil, sulphur, asphaltines, polymers...

As RCA has mentioned, the stuff has the ability to form impressive deposit concretions, very quickly. These are called "clinkers" in power boilers, and some technicians have been known to open a peep hole and aim a shotgun at them to dislodge the ones in their precious boilers. Not an option in an engine...

If I had one of these engines, I'd stick to fuels that were as close to the original spec of the original manufacturer as possible - diesel fuel, bio-diesel, SVO, and well cleaned and dewatered WVO...

Just my opinion... specs for "Bunker" may vary by region/state/province/country... but not by enough that I'd burn it in an engine, I'd bet...


 

[veggie]

How about blending it to reduce the viscosity.
If you can get the Bunker cheap enough, it might reduce your overall fuel cost by cutting it with regular diesel.

veggie

[billswan]

How about blending it to reduce the viscosity.
If you can get the Bunker cheap enough, it might reduce your overall fuel cost by cutting it with regular diesel.

veggie

Veggie

My goodness did you not read what the resident expert on oil's wrote?

I think what cognos wrote says it all forget about those types of fuel...

Unless you have a boiler live way out in the sticks and need volumes of heat.

Billswan

[rcavictim]

How about blending it to reduce the viscosity.
If you can get the Bunker cheap enough, it might reduce your overall fuel cost by cutting it with regular diesel.

veggie

Veggie,

You don't seem to grasp the significance of the miriad sharpoids in suspension.  Cut the bunker with 50% clean diesel and your sharpoid damage will get reduced by 50% in a given time period.  Dilute by 90% and your damage still accrues, just 1/10ths as fast but it still accrues.

I had the same problem trying to use WATF which contains many abrasive fines as engine fuel.  Diluting with diesel just extended the period before I had to pull the injectors and clean the crud off the tips.  We are talking run times of less than an hour between cleaning on my VW Rabbit diesel engine. I stopped my experiments with this fuel before I ruined my injection pump.  I have oil I cannot use in an engine until I build a super duper filter or a centrifuge. It would burn well in an appropriate furnace however.

[cognos]

You can blend it all you want, you'll still be left with seriously abrasive particulate contamination - how much engineered highly-abrasive sand can you live with in your fuel, no matter how cheap it is? Let alone the asphaltenes - that will drop out of solution as soon as you dilute and upset the solution equilibrium, plugging everything with black glass, mixed with sand and catalyst?

A fuel of desperate last resort, if anything. In my considered opinion. Your actual experience may be different, since I've never done it, and knowing what I do, never will! I know what cat cracker catalyst does to equipment specifically designed to handle the stuff - exotic alloys, 8" thick refractory-cement-lined monel-steel production vessels with stainless-steel needles for "rebar", crazy-money pumps and valves... and the stuff eats 'em all, eventually... like they were made of butter... eats up the nozzles in the boilers pretty regularly, too... and as far as ash, ya, it's a highly ash-producing fuel, even in a boiler!