3. Increase in Insulation Thickness in Preheater
In one of the new project it was discussed with suppliers to increase the preheater
Hysil insulation thickness by average 100 mm, initially some of the suppliers were
not ready for the same because they were worried about the condensation and
shell corrosion due to lower shell temperature, after discussion they got convinced
that there is no possibility of moisture ingress due to additional insulation thickness
(two layer of insulation and one layer of refractory) hence shell corrosion risk is
not envisaged, additionally we shall also have the internal surface painting to protect
the shell. Then all suppliers offered the same by optimizing their velocity profile in
PH cyclones and risers. One of them have increased it partially. This additional
insulation concept will result in heat saving by around 6-8 kcal/kg clinker due to
reduction in shell temperature by 10-15 %.
Standard v/s Offered Additional Hysil Insulation Thickness:
Increase in Insulation Thickness
Data Unit S1
Standard Refractory Size
Refractory mm 115
Insulation mm 115
Weight of Refractory + Insulation Ton 2752
Surface area of Pre-Heater Cyclone m2 9423
Weight of Steel Ton 1882
Avg. Surface Temperature (Approx.) °C 100
Radiation Losses Kcal/Hr/m2 506
Convection Losses Kcal/Hr/m2 337
Total Losses Kcal/Hr/m2 843
Approx. Heat Consumption losses Kcal/kg.Clk 26.5
Offered Refractory Size
Refractory mm 114
Insulation mm 215
Weight of Refractory + Insulation Ton 3227
Surface area of Pre-Heater Cyclone m2 10089
Weight of Steel Ton 2015
Avg. Surface Temperature (Approx.) °C 80
Radiation Losses Kcal/hr./m2 328
Convection Losses Kcal/hr./m2 220
Total Losses Kcal/hr./m2 549
Approx. Heat Consumption Kcal/kg. Clk 18.5