Energy Analysis and Operation of Steam Generators in Conventional Thermal Power Plants

摘要

The main goal of this work is to develop a suitable method, base don practical data, to determine the temeprtures of the combustion gases and the values of relevant parameters related with heat transfer phenomena inside the boilers of conventional thermal power plants. It fact, the knowledge of the flame temperature, the real temperature of the gases in the furnace and the gases temperture etween the heat exchangers of the boilers, provdes an improtant tool for the design and operation of this kind of installation. The method is built, through a computer aid calculation model, using the values of the efficiecy tests of the fourth steam generator group of the Setubal Thermal Power Plant, whose boiler is a conventional cycle of the powr plant is done, with the calcaltion of an approximate value of its efficiency and of the influence that hte feed water regeneratige heating, the reheating cycle and the nonisentropic expansion process inthe turbine has on that value. The second step is the energy analysis of the steam generator group, with the identification and quantification of the energetic losses and of another relevant parameters of operation. Finally, using a method of iterative cycles, the gases temepratures are estimated through the use of energy balances. The comparison of the calcualted temperature at the outlet of the boiler, with the experimental temperature (the only one that is known experimentally) shows the validation of the method.