It is obvious to me that we are talking about different types of pulverizer and boiler systems. Mine is a B&W Drum type negative pressure natural circulation water wall boiler.
We do not have tilting burners so upper and reheat temps are controlled by loading the top burner mills with less loading, thus less amps.
To tell if one of our pulverizers is malfuncitoning we have people checking them hourly for anything wrong. In the control room I have amp gages, differential air gages Primary air flow and temp gages and secondary air gages along with feeder controls.
To see if something is amiss I look at the amps vs feeder loading (High amps vs low feeder load) for each mill. Then Primary air (low air flow vs feeder load) and mill air temp.
I then check the HEAT RELEASE vs fuel flow. A dropping heat release means am not getting enough fuel into the boiler. It may be a partial feeder pluggage, a slipping feeder belt or low Btu coal. If it is a big rock it will jam the feeder and trip it, then the mill.
An very rapid increase in HEAT RELEASE means I have bogged a mill and it is now blowing out excessive coal into the boiler. Very dangerous, possibility of a boiler explosion exists.
Finally each pulverizer has it’s own characteristics. One may run with a higher amp load than others at the same feeder load. Certain others may bogg or puff while starting up. I know my mills, which ones will bite you in the butt and which might (notice I said “might”)not.
And if any of these run out of coal, the hot PRIMARY air leakage will back up through the feeder and into the silo possibly causing a hopper explosion. We have to send a man to the feeder floor to close the gate between the hopper and the feeder.
I spent 40 years as an, Operator, Supervisor, Start up Engineer, Shift Supervisor, and Shift Manager for Comm Electric, NSTAR, Sythe, Exelon, General Electric, Wheelabrator, and several private developers. I have done Coal, Oil, Natural Gas, Biomass, and Trash.
I have also hired and trained about 10 crews and reviewed the hiring of five more, I am not doubting your ability, every plant is different.