My guess would be four to five hours for a 30,000 gallon car, based on one hose. I used to drive tanker trucks (6,000-7,500 gallon tanks) and these would take about an hour to unload by gravity.
With the penchant people and businesses have for circumventing and breaking rules… I guarantee it.
‘TankTrain’ cars are regulars in Albany, NY. I’d say they run maybe 5 cars per unit.
I used to haul tankers over the road MC707 class stainless steel 7000 gallon capacity hauling foodgrade products and non foodgrade. We never mixed the trailers IE If their first load was foodgrade that was their load for the life of the trailer.
One haul I liked was from Cincinnati, Ohio to Green Bay, Wisconsin, I forget the product name but it was loaded heated and maintained heat by engine coolant built into the trailer. Each trailer was completely cleaned and sterilized before the next load including all safety devices on the trailer. When I arrived in Green Bay with my first load it was suggested to me by the unloader to open the top hatch and fore and aft fittings ( standard two inch thread fittings with sealed caps) and bring a hammer to punch out the solidified product before unloading. You also had to break up all the solidified product from the top hatch as it would plug solid the vent valves, We hadto leave the top hatch sitting on the tie down threaded rod to admit air as I never trusted the vent valves after that first load.
Three months later another driver failed to do as I explained and had to call saftey to explain he wrecked/crushed a brand new MC707 trailer on it’s first load. $86,000 gone in an instant.
Over in Revere, Mass were long tracks (4 of em) that I later found out were the primary unloading/loading points for East Coast oil products in WW II The Boston and Albany Railroad had a switcher assigned 24-7 from 1942 to the end of the war. The tracks held 40 cars each and were pulled according to my Engineer back in 1973 every two hours and the average tank car back then was a (for the times) a staggering 8000 gallons per car!! The local delivery tractor trailer tankers back then averaged 4 to 5000 gallons which were considered to be huge.
Soory guys I digress too much but it is interesting to see the difference in size on equipment between a few decades makes.
James Shanks
When I was a kid in the 60’s, when the county highway department was paving a road, they would have the tar delivered to a nearby rail yard in a tank car. They had a 1940’s Chevrolet truck that had a boiler on it. There were pipes that connected the boiler to the rail car for heating the tar. I assume there were pipes inside the car that the steam flowed through. Then the heated tar would be pumped into the tank of a tar spraying truck, I suppose using steam pressure.
I would not think it is done like that anywhere anymore.
Strasburg RR has been known to use one of their steam locomotives to heat up tankloads of vegetable oil so it can be transloaded into trucks.
But lots of industries still use steam to heat up cars for unloading. Strasburg just has a mobile source…
Asphalt in tankcars is still heated by steam pipes in the car when its time to transfer the asphalt out of the railcar.
A steam generator turns water into steam—and that steam is used to heat tank cars. The generator is located in the enclosed building alongside the hot-oil heaters. Its source of heat is the thermal fluid that is heated by the hot-oil heaters. Photo linked from the article at the site below.
The link below is to a paving trade magazine article about the C.W. Matthews’ Rockmart, Georgia Asphalt Terminal
http://www.hotmixmag.com/index.php?option=com_content&view=article&id=111&Itemid=124
From the article:
The huge storage tanks at the terminal are heated by hot oil that circulates through coils installed in the tank bottoms. Each tank has independent temperature controls enabling different tanks to maintain their contents at different temperatures. Tank cars are heated with steam to raise the temperature of the asphalt and decrease its viscosity so it can be pumped out of the tank cars into the storage tanks.
Lots more photos and text at the link.
Now Conrail Shared Assets did try the swing bridge method of unloading tank cars. Didn’t work too well.
Too soon?
What I meant was road paving. When a road is paved (tarred or sealcoated) today, normally a truck delivers the tar directly from the source to the site rather than sending a tank car there and transloading it to a truck. It is possible it is still done, but it would be uncommon today.
I used to work at a chemical plant where we used compressed air to assist in off loading sulphuric or caustic acid tank cars, an air to liquid propane heat exchanger to vaporize the liquid propane thus providing the pressure to offload the tank car and finally a steam powered/heated vapourizer to vapourize liquid hydrogen sulphide providing the motive force to move liquid H2S into storage bullets. All the tank cars had liquid and vapour relief devices which sometimes decided to lift at lower than original/design/spec set pressure. That created some exciting moments while trying to get the tank car depressured and the RV/SV repaired/replaced.
jumper- That sounds way too exciting. Do the workers wear any type of protective clothing or masks to do that kind of work?
Norris, anyone handling large quantities of hydrogen sulfide certainly should have protective gear. I never dealt with more than enough to precipitate cations when I was taking qualitative analysis in college so I could see what cations were present in the unknowns I was given to analyze. Even that little bit was dangerous–and when I think of how little protective gear we had 50+ years ago, I sometimes shudder.