System and method for preheating a beater mill

A method for preheating a beater mill comprising:

• rotating a beater wheel disposed within the beater mill to facilitate circulation of a gas stream between the beater mill and a furnace fluidly connected to the beater mill via a pulverized fuel conduit and a flue gas recirculation conduit;
• generating a burner gas at stoichiometric conditions via a burner disposed within the flue gas recirculation conduit such that the burner gas joins and heats the gas stream circulating through the beater mill and the furnace;
• adjusting at least one of an air supply and a fuel supply to the burner via a controller such that the temperature of the gas stream at a entrance of the beater mill is within a target mill entrance gas temperature range;
• when the temperature of the gas stream at the entrance of the beater mill is within the target mill entrance gas temperature range, further adjusting at least one of the air supply and the fuel supply to the burner via the controller such that the temperature of the gas stream at a exit of the beater mill is within a target mill exit gas temperature range;
• when the temperature of the gas stream at the exit of the beater mill is within the target mill exit gas temperature range, reducing the air supply to the burner via the controller such that a oxygen level within the beater mill is below a maximum mill oxygen threshold;
• and
• when the oxygen level within the beater mill is below the maximum mill oxygen threshold, introducing a fuel from a fuel source into the beater mill.