ENERGY SAVING - CEMENT PLANT CASE STUDY
ACC plant at Madukkarai ,Tamilnadu
Installation of High efficiency Fan in E- mill
The previous Fan was for rated for a pressure drop of 1100 mmWG.On measurement it was found that
pressure drop requirement was maximum 850 MMWG. Apart from that the improvement in waste heat
utilisation and leakproof ducts reduced the false entry. Due to this the installed fan with 450 KW motor
was running at lower efficiency. It was decided to retrofit a new high efficiency Fan . The new operating
parameters were fixed at 850 MMWG at 800 m3/Hr flow.The retrofitted fan at 83 % efficiency saved 35
KW.The expenditure on this project was Rs 4 lakh and the savings in the first year was 1.38 lakh unit.
Optimisation of air requirement for Mixer basin aeration
The Raw mill homogenisation is done in amixer basin. For continuous aeration ,the compressed air is
utilised.It was observed that the compressed air pressure was only 0.8 KG/Cm2.The power consumed
however was 65 KW. On analysis of different capacity of blowers it was found that at same pressure and
for 2500 M3/Hr flow ,the power consumption is only 45 KW.Thus a savings of 20 KW was possible.
The blower was installed for mixer basin aeration at a cost of Rs 4 lakh. In the forst year itself the
savings were about 1.65 lakh units.
Flocculant addition in thickner and filteration
The enrichment of lime takes place in flotation and enriched material goes to thickner for settling.It was
observed that the settling was slow and the water overflow was carrying fines below 350 mesh.We tried
with various flocculants .Addition of a particular flocculant increased the settling and material carryover in
the overflow was reduced to zero.The same principle was applied to filteration for improvement in cake
thickness.this resulted in reduction of vacuum pump operation and at a cost of rs 2 lakh/year about 1 lakh
unit was saved.
source: Bureau of Energy Efficiency,India