Cement, Energy and Environment

29 impact upstream and downstream of the system. Dust accumulation on the outside of the boiler tubes would make the heat transfer ineffective initially, affecting the operation of the power plant. • After the installation of WHRB, increase in pressure drop in Preheater section is most critical issue. This may resulted in low fan margin consequently decreases in production. • During forced or planned shutdown of the boiler, the pre heater exit gases will again need to be routed through the Gas Cooling tower. For, this purpose, Shree installed a pre-heater exit valve which weighs 25T, is 18 m in height and 3.4m length. As the valve to be installed is huge in size and is heavy, requires time and hard labor to open or closed. • There are some other technical problems related with WHRB which are further the complication in the smooth operation of the waste heat recovery project. : Dew point limits for WHRB, Water starvation and circulation ratio hampering, Pressure drop permissible in the unit, Operational Constraints of pre heater exit fans etc. PARAMETERS PREMEDITATED FOR DEVELOPMENT OF WHR SYSTEM FOR POWER GENERATION • Sources and uses of waste heat • Upset conditions occurring in the plant due to heat recovery • Dust content and Buildups in boiler • Pressure drop across the boiler • Temp and enthalpy of waste gases • Dew points of gases • Availability of space • Suitable option for co-generation etc. REMEDIATION In order to control the problems on the account of the dust, we implemented a dust dislodging system i.e. mechanical hammering system on the left and right of each section of the WHRB. The function of the dust dislodging system, as the name implies, is to remove the dust from the WHRB panels. The salubrious operation of the dust dislodging is very critical for proper functioning of the WHRB. IMPLEMENTATION OF WHR In order to successful utilization of the waste heat, Shree first installed R&D boiler at Unit-I. After detail study and review of process and other parameters of R&D boiler, system was designed and implemented for 43 MW cogeneration power units through waste heat utilization in all existing clinkerization units. The project activity involves implementation of new and innovative technology (utilize waste heat fromsix stage preheater) for the recovery of the waste heat from exit gases of pre- heater and clinker cooler. The schematic diagram of clinkerization unit after implementation of WHR system has been sighted here (Fig-2). Figure 2