Cement Energy and Environment

.. Improving the Cost Competitiveness through Energy Performance in aCement Plant M.K. Jha & N P Singhai Prism Cement Limited A K Mishra, Rabindra Singh National Council for Cement and Building Materials ABSTRACT Indian Cement Industry has been striving hard to improve energy consumption to be competitive and increase profitability. Roles of available equipment, top management and trained and experienced manpower are great contributors in reducing energy consumption and energy costs for a cement plant and it is amply demonstrated in case of Prism Cement ltd. The paper highlights the affects of various Energy efficiency improvement efforts carried out based on the findings of Energy audits carried out by inhouse and external teams like NCB. Though best cement plants in India and abroad have achieved heat consumption of 660 - 670 kcal/kg clinker and power consumption below 60 kWh!Ton of blended cement, there are many plants consuming more than 70 kWh!Ton of cement. Prism Cement has been successful in bringing down its SEC (specific Energy consumption) from 783 kcal/kg equivalent product to 737 kcal/kg equivalent product and power consumption from 74.52kWh/MT Cement to 63.26 kWh/MT Cement for Unit-1 & from 75.56 kWh/MT Cement to 65.28 kWh/MT Cement for Unit-11 by adopting various optimization measures for cost competitiveness and thereby achieving PAT targets of energy consumption. We are confident that we will achieve even larger milestone in Energy consumption in future with active co– operation of management, staff and time to time guidance of consu ltants like NCB. 1.0. INTRODUCTION: M/s Prism Cements ltd. has two units with total production capacity of 5.6 MTPA supplied by M/s F L Smith, Denmark . The Unit I kiln with rated capacity of 6000 TPD clinker is having a 6 stage The Unit II kiln with rated capacity for 7200 TPD clinker is having a 6 stage preheater and an ILC calciner with cross bar cooler. Energy Audit of the plant was carried out by NCB and various measures for energy performance improvements were implemented. In market Prism is known through the Brands like Champion,Duratech and Hitech. 2.0. ENERGY PERFORMANCE IMPROVEMENT MEASURES: 2.1. Grinding mills optimization An audit was conducted to know the performance of the mills and based on outcomes of the audit measures were taken at different fronts for process optimisation to reduce specific power consumption. Few of activities are: • VRM mill reject system was optimised with respect to the nozzle ring velocity and material load on the belt conveyor. • Reduction in VRM outlet temperature to 80°C from 90°C. • Improvement in efficiency of magnetic separators. • Elimination of repetitive breakdowns through QC measures. • Studied the load pattern behaviour of various equipment and identified the causes for increased power consumption among similar type of equipment. • PID loops re-tuning to meet changes in process . • Torque control mode operation for roller presses was installed. • Arresting leakages and emissions from stacks/dust collectors. preheater and two calciners ILC & SLC with coolex • Improvement in C3S of clinker by usage of Pet cooler. coke. 4