Dalmia DSP Success Story
TECHNICAL PREPARATION 17
- Capacity requirement with respect to operating
grindability: Capacity requirement given initially
was of 570 TPH @ 15% residue on 90 microns,
considering kiln guaranteed capacity of 7,200 TPD,
but during order finalization the kiln guaranteed
capacity increased to 8,000 TPD, hence raw mill
guaranteed output requirement was increased from
570 to 600 TPH. The raw meal residue maintained
in both the operating lines are around 17–18%
on 90 microns and the operating grindability was
around 4.5 kWh/t. The mill output requirement for
kiln potential capacity of 9,500 TPD clinker comes
to 656 TPH at 22 running hours per day of mill.
The capacity of mill was selected in such a way
that at operational residue and grindability of line 1
and 2, the line 3 mill shall produce more than 656
TPH. We have also asked suppliers to give us the
guarantee (indicative) on 90:212 microns residue at
ratio of 10:1 for better control of grain size to ensure
improved burn ability of kiln feed.
- Feed moisture: The maximum feed moisture given
for design was 4%, however the actual average
moisture at existing limestone was around 1–1.5%,
hence guarantee would be on 1% feed moisture.
- Available gas temperature: We have WHRS
concept since beginning so we intended suppliers
to design the mill in such a way that it can run with
150 ̊C (PH boiler outlet temperature). It was also
discussed that since the material grindability is very
