Dears,

We are having 

  1. High flame impulsion (10.5 N.h/Gcal) for 100% coal
  2. Fluctuation on pre-calciner (RSP) outlet temperature (850 - 880 oC), caused by unstable coal feeding, leading to variable calcination degree (92 - 95%).
  3. Fluctuation on kiln feed LSF (97 - 120)
  4. AR = 1.45, SR = 2.75

Questions:

  1. we are facing the problem of burning zone ring formation (at meter number 50); which one of the above may be the main reason of this problem?
  2. how can I determine burning zone length?

N.B. short dry kiln, 78 m useful length & 5.2 m useful diameter.