Cement and Energy

ENERGY EFFICIENCY IMPROVEMENT IN INDIAN CEMENT INDUSTRY National Council for Cement and Building Materials (NCB), New Delhi Introduction E nergy is one of the major cost components in cement manufacture and accounts for more than 45% share of the total production cost of cement in India. Accordingly, energy conservation has to be accorded highest priority in the overall cost reduction programme in cement manufacture. An integrated approach towards achieving improved energy efficiency in cement manufacture has been the prime objective of NCB. This covers various aspects, such as energy audit, energy management and monitoring, continuing education, energy awareness motivation schemes. The industry over the years has benefited from this approach as is evident from the regular monitoring studies carried out by NCB. The cement plants have successfully adopted the various energy conservation measures and their specific energy consumption levels have reduced significantly over the years. Energy utilisation in Indian cement industry Based on a recent energy monitoring study carried out by NCB in a large number of cement plants, the energy consumption levels of the industry are as under: Thermal energy consumption The average specific heat consumption level of dry process plants was 780.12 kcal/kg clinker in 1995- 96. As compared to 1992-93, there was a reduction of 1.6% in the specific heat consumption. Frequency distribution of dry process plants on the basis of range of specific heat consumption is shown in Fig.l. This brings out that 55% plants are operating below 800 kcal/kg clinker, 40% plants are operating at 800 to 900 kcallkg clinker production, whereas 5% are operating above 900 kcal/kg clinker. Fi&.l JiliEQUENCY DISTRIBUfiON OF DRY PLANTS BASED. ON HEAT CONSUMPTION LEVELS 40 - - 3S ~= 30 30 lS ... ~ 10 Ill IS ~ 10 <( 10 ~ < 750 7SO. 800 800. 850 8SO . 900 > 900 HEAT CONSUMPTION RANGE (kc:aliltc CUNKER) (DATA OF U PLAr>'I"S) Electrical energy consumption The average specific power consumption level of dry process plants was 104.35 kWh/tonne cement in 1995-96. As compared to 1992-93, there was a reduction of 7.01% in specific power consumption. Frequency distribution of dry process plants on the basis of range of specific power consumption is shown in Fig:2. Fic.z FREQUENCY DISTRIBUTION OF DRY PLANTS BASED ON POWER CONSUMPTION LEVELS 60 - -- ~ so 43 z - ~ 40 ... JO "' JO 0 r-- ~ 10 IJ <( n 9 Ill 10 n s 0 II <9S 9S ·lOS lOS · liS liS · 11S > llS POWER CONSUMPTION (kWhlt CEMENT) (DATA OF 26 PLANTS) 5