Exothermic Engineering, LLC

PC-Fired Boilers

Pulverized coal (PC) fired boilers are the most common in utility service.  Exothermic Engineering takes pride in its work in this area of applying first principles in a coordinated approach to properly balance the system from bottom to top.  Although we can jump into the process to help our clients at any stage in combustion improvement, our complete First Principles Program includes the following (typical of plant with MPS, MB, MBF or HP mills):

        -Obtain a full range of expected fuel analyses as well as
          necessary drawings, dimensions and data on the boiler,
          burners, classifiers, coal conduits, mills, feeders and fans.

        -Properly test the mills, or obtain proper mill test data.

        -Certain mill modifications and repeat testing may be
          recommended at this time to improve fineness and fuel
          balance.

        -Perform mill dribble tests to determine minimum throat
          velocity

        -Perform mill response tests to evaluate proper balance of mill
          primary air/fuel ratio at high load.

        -Calculate minimum primary air (PA) flow based upon plant
          elevation & coal conduit I.D.

        -Correct mill PA/Fuel Flow curve if necessary based upon
          minimum PA flow and mill response tests.

        -Correct throat ring size, if necessary to reject pyrites and
          minimize dribble.

        -Calculate burner nozzle velocity.

        -Evaluate and adjust if necessary, the unit excess O₂ curve.
         This involves consideration of slagging, fouling, steam
                       temperatures and sprays.

           -Determine total air flow.

        -Evaluate FD and ID fan sizes, if necessary.

        -Calculate burner secondary air velocities (inner and outer).

        -Redesign burner and air register sizes if necessary.

        -Reconfigure and/or tune controls as necessary to
          accommodate new settings.