Articles

What are the fuel requirements for refractory kilns?

  1. Temperature and flame structure requirements
  • Reach target firing temperature: common firing range for refractories is about 12001800C1200\sim1800^\circ C (depends on product and process).
  • Controllable flame: stable flame length, rigidity, and radiation; adjustable temperature field to avoid over/under firing and thermal-stress cracking.
  1. Atmosphere control and product cleanliness
  • Oxidizing/reducing atmosphere controllable, especially for iron-bearing, carbon-bearing, or valence-sensitive products.
  • Low contamination: low SS, low ash, low alkali metals, low chlorine; avoid introducing Na2O/K2ONa_2O/K_2O flux impurities that cause surface glassy phase, sticking to kiln furniture, or discoloration.
  1. Slagging, corrosion, and lining life
  • In solid fuels, ash Fe2O3Fe_2O_3, alkali metals, and low-melting eutectics promote slagging; in heavy oil, vanadium and sodium form highly corrosive molten salts, accelerating refractory attack.
  • Fuel and combustion method should avoid direct flame impingement on key areas and reduce local overheating.
  1. Process and economics
  • Stable metering, continuous supply, wide control range, easy start/stop; low cost per unit heat and reliable supply.
  • Emissions can meet limits: sufficient control margin for NOx/SO2/PMNO_x/SO_2/PM.