Refractories that will optimize your              Tertiary air duct

In grate cooler kiln systems, the tertiary air duct helps to recover valuable energy.

Air from the grate cooler is filled with highly abrasive clinker dust as well as residual alkali vapors. When it is travelling through the tertiary air duct at a velocity of 25-30 m/s and an initial temperature of about 1050°C, it wears down the lining - particularly at bends and dampers. Abrasion resistance and alkali resistance are both important in tertiary air duct refractories.

The refractory solution for the tertiary air duct is straightforward:

• Alkali- and abrasion-resistant brick in straight sections, Viking 330. 
• Alkali- and abrasion-resistant low-cement castable in curved sections, Denscast 50 A QF .