Power Plant Gyan

Circulation is the flow of water, steam or both through the tube circuits of a boiler (from boiler drum,boiler down comer, riser water walls ). Adequate circulation is necessary for all the circuits to remove the heat  from the boiler furnace and cool the heating surfaces by carry the heat. Due to carry the heat from the the metal surfaces the temperature of metals remain cools within a specific limit. Sufficient circulation in provided in steam water circuit to avoid any salts deposits on the inner metallic  surface of boiler. In a circuit if the fluid enters at the inlet and leaves the outlet to the next circuit it is a once through system.   If part of the fluid from the outlet of the circuit is returned to the inlet of the same circuit it is a re circulation system.    In a boiler the following circuits always adopt once through system. Economiser Super heaters Re heaters In these circuits the inlet pressure of the fluid effects the circulation.  The water walls or evaporator circu

Introduction :- The Furnace Safeguard Supervisory System (FSSS) is designed for  To assure the execution of a safe, orderly operating sequence in the start up & shut down of fuel firing equipment. To prevent errors of omission and commission in following such a safe operating procedure. The system provides protection, should there be a malfunction of fuel firing equipment and associated air systems. The safety features of the system are designed for protection in most common emergency situations. Basic Functions of FSSS:- Prevent any fuel firing unless a satisfactory furnace purge sequence has first been completed.  Prevent start-up of individual fuel firing equipment unless certain permissive interlocks have first been satisfied.  Monitor and control the proper component sequence (manual or automatic) during start-up and shutdown of fuel firing equipment. Make continued operation of fuel firing equipment subject to certain safety interlocks remaining satisfied.  Provide components

The notification from MoEF & CC dated 7th December-2015 amends existing norms related to emission of SPM and introduces new norms for emission of SO2, NOx and Mercury from Thermal Power Plants (TPPs). I t also specifies modified limits for specific water consumption by TPPs. To convert existing once through based condenser cooling system to recirculation type. Different limits are specified based on capacity of power plant and year of installation.   NEW REGULATIONS ON EMISSION A summary of new regulations on air emission is given in below: Date of Installation PM SO2 Nox Mercury (Hg) Before 31-12 -2003 100 mg/Nm3 600 mg/Nm3 for <500MW 600 mg/Nm3 0.03 mg/Nm3 for >=500MW 200 mg/Nm3 for >=500MW After 01-01-2003 & Upto 31-12-2016 50 mg/Nm3 600 mg/Nm3 for <500 MW 300 mg/Nm3 0.03 mg/Nm3 for >=5

Generator cooling system INTRODUCTION In a big turbo-generators where a huge mass of metal is used. As  as current flows through conductors  large heat is generated in the winding of stator and rotor of generator. When turbo generator is started then heat generation in metallic parts are starting if this heat is not removed from the generator then this is chance to failed the generator winding.    As i n generator large amount of heat is generated and is not possible to dissipate this heat from natural system. So forced cooling system is adopted. in force cooling system air or hydrogen gases are used.      In smaller turbo-generators, the cooling is by air circulation.  In bigger turbo generator hydrogen cooling system came in the field.      So e fficient cooling & ventilation system is required for generator to keep temperature of winding bellow certain limits. For the cooling of generator following system is adopted Air cooling system - In this air is forced into the generator