Cement, Energy and Environment

77 Reason for low output and higher energy consump on of mill - · Mill outlet residue was high up to 52% on 38 micron because of inadequate media pa ern of mill which results in higher circula ng load of mill and this results in decreasing the efficiency of the separator. · Grinding media filling level is low in mill. Grinding media filling level was 26.20% in mill with different sizes of balls. Op mum filling level of media was not done. · Frequent Jamming of mill diaphragm due to wear & tear of grinding media which results in increased outlet draught & increase of material filling level of mill and combina on of above factors finally results in reduc on of feed. · When both Cement Mill 1 & Cement mill 3 were run combined then hoppers of clinker, gypsum was not maintained by the operator because tunnel belt is common for all hoppers. Earlier Clinker silo was not commissioned therefore clinker was fed into the mill through tunnel belt at clinker yard. Circuit of the mill is designed in such a way that if material is taken from clinker yard then it first goes into the Cement Mill-1 Belt, then into Cement Mill-2 Belt and then finally it goes into cement mill-3 . Material travelling me was high due to this arrangement and this is one of the factors of higher power consump on in Cement Mill sec on. To avoid this a clinker silo was commissioned and then material is feed in the mill through DBC (Deep Bucket conveyor) at Clinker silo, This DBC feds the material directly in the Cement Mill 3 hoppers. Following improvements were done: · Grinding media pa ern changed. Earlier grinding media op miza on was not done. Following ac ons taken to op mize the size and quan ty of grinding media 90 mm 80 mm 70 mm 60 mm 50 mm 3.0 9.0 12.0 7.0 3.0 100 mm 90 mm 80 mm 70 mm 60 mm 50 mm 3.0 3.0 6.49 5.0 5.0 4.0 Grinding media pa ern 1st chamber before Grinding media pa ern 1st chamber a er