You can see the assembly at the top of the stack, from my understanding the top rig has the spray nozzles. IIRC a few months back someone was talking about them with a closeup (may have been on one of steam facebook groups)

Interesting, but stack arrestors only solve part of the problem. Sparks or burning embers also come out through the grates, Most go into the ash pan, but all it takes is one to start an inferno. Oil is the better choice. Depending on how much oil it takes to make a round trip, it might also save money. Waste oil is plentiful, relatively inexpensive, produces no ash and burns cleaner than coal.

Are you familiar with the term "drooling"? It's what happens when there is an abundance of oil flow and insufficient atomizer in an oil burning locomotive (oil guys, correct me if I'm way off base). Regardless, this situation produces globs of fire dripping below the firepan, spilling out onto the ROW, and just as great of a line side fire hazard. Good firing habits prevent this just as they do with coal burners, but it still happens.

Secondly, waste oil if not properly filtered for the heavy impurities will produce ash and cinders. Granted, it is not to the same degree as a coal burning locomotive, however, oil burners are not immune from starting fires along the ROW. They just lessen the potential.

Best,
DC

I have understood that D&S routinely followed all steam trains with a motorized section car equipped with a water tank and spray pump, with the intent of spotting and extinguishing any fire that was started by the locomotive. I also understand that they use a helicopter to patrol the route and search for fires that might be started by the trains. I also assume there must be a method or arrangement for the railroad to contact the Forest Service for a quick response from the Forest Service fire fighters.

Also, apparently, the D&S and the Forest Service agreed that running the D&S steam locomotives during the drought conditions existing at the time of the fire starting was in compliance with the Forest Service fire danger rating.

So, given all of these precautions, how could this fire have been started by a D&S train?

If the train did start the fire, considering the last point about the Forest Service fire danger rating in particular; it would seem that the Forest Service did not impose enough of a restriction on the D&S steam train operations. So wouldn’t the fire be the fault of the Forest Service? Certainly, they had the power to prevent it.

"Waste oil", if from gas stations or garages, often has ATF, power steering fluid, anti-freeze, and maybe some other impurities that just won't burn. It is also considered as a hazmat in many cases. Been there, done that-

EDM
Superfund, NJ

Note that initial treatment for any waste oil ought to involve centrifugal separation of the 'aqueous materials' (including the fluids EDM just mentioned) and removing most of the particulates as an additional step, for example by passing them through filter media on the way to the centrifuge, is sensible. You'd run the plant as continuously as you had 'feedstock' and volunteers, so even a comparatively small and inexpensive treatment setup would likely work for an operation the size of the D&S, especially if waste oil were used mostly at peak fire time and not as a permanent conversion.

I believe there are also some suspended polllutants in the waste oil, such as ZDDP, that might come to be restricted in material to be burned in the open. What additional treatment steps might then be required is up to people more expert than I am.

Or, you burn refined clean oil - using an efficient combustion system like that devised at SLM / Sulzer.

Drifting further off topic but I wonder if you can use WVO (clean, dewatered waste vegetable oil) as fuel. IIRC, it has about the same BTU as #2 fuel oil. Unless I calculate incorrectly, it's currently about $1.70/gal retail plus delivered if it's available locally. I've been around biodiesel buses that kind of smell like french fries which might help local restaurant sales after a trip. Just wonderin'.....

I think that's what Grand Canyon and the Disneyland Railroad burn... I know they smell a bit like cooking oil. ha.

I wonder why the D&S doesn't install netting around the top of the ash pan or fabricate something similar to an Anderson or Cyclone spark arrestor front end. After all they're considering burning oil, and these improvements wouldn't cost a lot. I know there aren't any guaranties, but it would be a preventative along with a following vehicle or train. Might be worth it for the PR value of showing more actions done to prevent fires.
Tom Hamilton

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Yes, the circle of pipe has nozzles which shoot across the top of the stack. They're piped off the fireman's injector with an on/off valve in the cab. When I fired there in 2016 we ran them from Hermosa to Rockwood, then from High Bridge/Tacoma to just north of Snowshed Slide.

TT

Keeping both threads up to date, story from Durango on the return of service.

https://durangoherald.com/articles/2424 ... olls-again

How reliable are the water spray stack nozzles in preventing the emissions hot enough to start fires along the track? Were they in operation on the train that is suspected of starting the 416 fire?

If the present water spray system is not nominally 100% reliable in preventing fires due to stack emissions, is it possible to design and build a system that is nominally 100% reliable?

Regarding the D&S conversion of coal fired locomotives to oil firing, is this work based on existing development, so it is just a matter of mechanically executing an oil firing system that has already been successfully proven? Or will the conversion require new research and development to perfect a workable system for converting D&S locomotives?

The nozzles are arrayed around the outside of the stack spraying water into the stream of gasses and cinders exiting the stack at a high velocity when the engine is working hard. I don't know how far into the gas stream it penetrates before it is evaporated into steam and carried up with the rest of the exhaust gasses but probably not very far. It almost certainly douses some of the cinders around the periphery and helps, but nowhere near approaches 100% effectiveness.



Firing a steam locomotive boiler with oil is a straightforward conversion using thoroughly proven technology. Calculations are required to size the burner, fire pan, combustion air openings, and exhaust nozzle. Some fine tuning may be require to get everything right but it is by no means an exotic new technology.