We have faced the serious coating formation at 12 to 26 meter of Kiln and plant have to be forced stopped for coating removal. I am attaching the three files for your observations:
1. photograph of the Kiln coating.
2. Observation about the breakdown.
3. Analysis data for coating, Rawmix and coal.

I may request you to please look into the coating formation details and furnish us your valuable comments.

I have studied the data you have submitted. We receive regular reports of heavy coating and ball formation associated with petcoke firing. I note that on the 12th & 13th, prior to the kiln stoppage the petcoke firing in the kiln had been increased to 70 per cent. However, the clinker sulphate levels are not excessive and neither is the sulphate in the coating sample. One othet item of note is that the MgO content of the clinker has risen to above 1.5 per cent on the 11th, 12th and 13th. In my experience only minor changes in the MgO content can lead to significant changes in the coating tendency of the kiln and also the formation of clinker balls. Do you know the reason for the increase in MgO content?