hongminh:

My coal store had layout a coal pad depth on the floor and the distance from chain feeder to the surface of the floor is enough to ensure that it never take together the soil or concrete in operating.The level of coal in stockpile always maintain in a high level. The coal type same before.

I think may be change something in the chemistry composition of shale. Sometimes it has changes the position on the querry and the SiO2 content may be increase. Do i think correct?

Hello HongMinh,

 As long as your final raw meal chemistry did not change (ie  LSF : 100-101,     SM : 2.6   AM : 1.45) a change in the chemistry of the shale component would not affect the clinker chemistry.  It would only effect the relative percentages of each of the raw mix components necessary to make the raw meal to those targets.

I still think your problem is a sudden change in fuel ash content or chemistry, or a contamination issue. I suggest you take samples of your pulverised coal (and whatever additional fuels you might be adding) and check their ash content and the chemistry of the ash to see if there has been a significant change.

Regards,

Ted.

When we were using coal from different sources and mixing them in stacker reclaimer we used to experience variation in clinker quality though raw mix prepared used to be of fairly constant in terms of LSF,S.M. and A.M.

What Mr.Ted is pointing out is very correct.

Regards

Bhaskar