I would like to know the causes of very fine clinker produced from the kiln/in-line precalciner 4mx72m. I assume possible following causes : 1. short flame 2. big ring at upper burning zone (23-26m) 3. low kiln draft (O2 at kiln back end < 2%). Please give recommendations of effective measures to get clinker back to normal and clinker less dusty Regards,

can u send the details of clinker chemistry, type of fuel fired. are u operating at the causes specified by you?.

The most common cause of dusty clinker is excess sulphate over alkali in clinker. High sulphate cycling in the kiln can be caused by reducing burning conditions. Low back-end O2 would be a symptom of that. The ring in the kiln may be the cause of the low draft, therefore reducing conditions and possible high sulphate content. Alternatively it might be a sulphate based ring and therefore a symptom of the problem. Attempts should be made to balance sulphur and alkali inputs to the kiln and a high momentum flame must be maintained at the main burner of the kiln.

Best regards

Dr Michael Clark

Dear Tran

Can you define FeO content in your clinker? Because the reducing conditions in kiln system  brings to reducing Fe2O3 to FeO, because of which  partly decomposition of clinker (especially C3S) occur and as a result clinker becomes dusty.If this case occurs in your kiln, you must  eliminate the ring as soon as possible, and then normally calculate air consumption for firing your fuel and escape from reducing conditions in the kiln.

This is another factor, that brings to dusty clinker. Maybe my opinion can help you.

David