Cement and Energy

. :fN· ~- :lGY . ~ . ~-'" A QUARTERLY NEWS LETTER Vol. II No. 3 July 1998 • • • • • • • • • EDITORIAL BOARD R. Partha Sarathy Dr. S.P. Ghosh P.K. Tikku V.K. Arora S.V. Joshi CONTENTS Cost saving in grinding systems Concepts of clinker cooling and the IKN design Burning alternative fuels in rotary kilns Complete grinding circuits and their components 4 7 10 Centre for cleaner technologies 14 Concept of twin focal points 15 may be changed World Bank piloting fund 15 for emission trading National Energy Efficiency 16 Awards 1997-98 (NCB's) Forthcoming Events 17 For Private Circulation COST SAVING IN GRINDING SYSTEMS Introduction E nergy consumption accounts for a major proportion of c;osts within industrial production. More than 50% of the final costs for the production of cement arise through energy costs. A second more essential cost factor in the cement industry is the spare parts and the replacement of parts subjected to wear and tear. In these areas, the cost of works and foundry products are influenced by high energy costs. Since the first oil crisis in the 70s, the cement industry has tried to find a · more efficient process to reduce energy consumption and the wear of the plants especially in the grinding circuit. Despite this tendency, ball mills are still used exclusively in grinding raw meal and clinker, although it is known that in these plants, only 5-6% of the energy can be effectively used to mill the product. The remaining 94 - 95% loss of energy, caused by heating, wear and noise, cannot be avoided (Figure 1). =~----.~--..~~;:g Losses Heat •rtction SOund Vobtotion -- Wear Noise Figure 1. Energy conversion.