Cement Energy and Environment

2.3.3. Maximum Demand Reduction: Staggered run of equipment and time of day (TOO) tariff utilisation can reduce the maximum demand and also impacts negatively on overall Load Factor of plant, which in turn can affect the unit rate. • Time of Day Tariff (TOO) Utilisation: Stopping equipment during peak hour and maximising equipment run during off-peak hours can result in reducing power bill. Actual monetary benefit ranges - Rs. 9 to 10 lakh/month, depending upon capacity utilisation of plant. Adoption of energy efficiency measures , coupled with equipment efficiency improvement and process optimisation created opportunity to reduce the Maximum Demand (MD) of both Units. In U-1 plant got opportunity to restrict the Maximum Demand from 30.96 MVA in January 2015 to 29.8 MVA in April 2015. Similarly Maximum Demand for Unit-2 decreased gradually from 40.8 MVA in January 2015 to 35.84 MVA in April 2015. This resulted in not only improving Load Factor, but also reducing the fixed cost, demand side reduction on load. 3.0. FUTURE MEASURES FOR IMPLEMENTATION: 3.1. Process Fans Retrofitting: Study indicates that scope of - 900 kW saving is there with payback of < 1 year. Proposal has been sanctioned for implementation in phased manner. Effective implementation will reduce U-1 load further by - 1 MW, thus giving advantage on contract demand (CD} reduction. • Identified potential saving of 100 KW for unit-2 cement mill -1 separator fan through maintaining static pressure at fan inlet to around -545mmWG to -560 mmWG. This can be investigated through CFD study for reducing the pressure drop in the ducting or alternatively ducting needs to be optimized for reducing the pressure drop. • Areas have been identified for further load reduction to the tune of - 2 MW (both Units combined). These are under implementation & observation stage. 3.3. Cheaper Power purchase through Open Access, Power generation from Waste Heat Recovery System, Plant envisages to go for the use of alternate fuels and get the benefits under PAT scheme , Unit-1 Clinker Cooler upgradation, Optimisation of shutdown power. 4.0 RESULTS: The plant could achieve SEC of 737 kCai/Kg of equivalent product form the existing level of 783 kCai/Kg of equivalent product against the assigned target of 749 kCai/Kg of equivalent product in PAT cycle 1( 2014-2015). This resulted in appreciable saving to the plant. 5.0 CONCLUSION: By adoption of various measures discussed in the paper, the specific energy consumption has been reduced from 783 kcal/kg equivalent product to 737 kcal/kg equivalent product for the plant. Power consumption has come down from 74 .52 kWh/MT cement to 63.26kWh/MT cement in U-1 and from 74.65 kWh/MT cement to 65.28kWh/MT cement in U-11. The Plant has improved its cost competitiveness and confident of further reducing the thermal & electrical energy consumption by implementing the recommendations such as 3.2. Small Projects Optimisation: on Process retrofitting of the cooler in unit-1, optimization of kiln & cooler in unit-2 & waste heat recovery etc. **** 6