Old Coal

When I was doing my research & reading prior to taking the firemans' school at the C&TS, I learned a great deal about coal I didn't know before. A significant amount of the energy in coal isn't in the solid coke, but in the volatile gasses (eg. methane) also contained within the coal. Over time, the volatile gasses can dissipate. The coal looks the same, but it won't burn as we're accustomed to, or how the firebox was designed to burn it.

I experienced an example of this when firing down the 4% and coming into Chama. As you might imagine, the trip down the hill uses very little coal, so by the time we got to the 1st crossing, the volatile gasses were spent, and I had a layer of coke burning quietly on the grates. As the engineer opened the throttle as we got closer to the yard, the draft did not wake up the fire. The fire was about as thick as I wanted it to be, but the instructor told me to toss in a scoop or two and see what happened. The fresh coal really livened things up! Those few scoops brought the fire back to life, and we completed our switching with a few more scoops as instructed and a nice bright and lively fire that kept the pressure gauge where it needed to be and the engineer happy.

I couldn't imagine trying to run a locomotive with a fire of dead coal. Thick fire on the grates, no gasses burning above the fire, and nothing I do can make it work properly!

Dave