Cement, Energy and Environment

Results & Observa ons Enthalpy of steam is a func on of temperature and pressure. At lower temperature, enthalpy will be low, work done by the turbine will be low, turbine efficiency will be low, and hence steam consump on for the required output will be higher. In other words, at higher inlet steam temperature, heat extrac on by the turbine will be higher and hence for the required output, steam consump on will reduce. WHRB Turbine - As men oned above, the temperature of turbine inlet steam has been increased. The maximum allowed temperature limit of TG inlet steam was 356°C ini ally but a er discussing and taking of approval from turbine OEM M/s Siemens Ltd., it was increased to 400°C. Gains / Benefits achieved through modifica on of the system: - The efficiency of the turbine has increased which has resulted in more power output with less steam consump on. 1- As the turbine inlet steam temperature maximum limit has now increased to 400°C from 356°C. Now we do not need to open the bypass damper of cooler boiler flue gas, thereby avoiding the exhaust of waste heat of kiln. 2. Earlier lower steam temperature margin was maintained by opening higher de- superhea ng control valve and ven ng excess steam of high temperature in atmosphere. Now this prac ce has been stopped, thus, reducing the energy losses and saving of 700 Liters/hour water in steam de-superhea ng process. 3. We are now able to run ACC at lower RPM, whenever, turbine is at full load, thereby, achieving saving in auxiliary power consump on. 4. The specific steam consump on is reduced to 4.8 TPH from 5.5 TPH (saving of approx. 700 Kgs./hr.) a er implementa on of this scheme as steam enthalpy has increased due to higher inlet steam temperature. Effect of Steam Temperature on Turbine Efficiency Effect of Steam Temperature on Steam Consump on 53