Dear Ted,

Please we experienced some kind of coating on the tertiary air duct, due to this some part of the refractories are being wiped out with the coatings.

The chemistry of the sample we picked is attached below.

Also we had a red spot on our kiln, please when is refractory erosion caused by material chemistry and when is it caused by burner pipe alignments. (How can one differentiate the two situation).

Please kind explain or even send me any material on this.

Thanks for your usual help.

Regards