| In order to find solutions to situation that relatively low efficiency and pollutant emission. Developing a large capacity, high efficiency, low pollution and high parameter of unit is one of the focused ways to develop our power industry, and the technology of Supercritical as a tool to resolve this difficult problem. In other word, thermal analysis of Supercritical power plant owns high value.In this thesis, the author takes 600 MW Supercritical coal-fired power plant(the most common unit) as the research object and from the following aspects to analysis the object unit: this thesis on the basis of the second law of thermodynamics, and determines the location of the lower thermal performance in the thermal system, the size and as well the cause from “amount†and “quality†of energy, thus providing some beneficial information to improve the efficiency of overall system for designer. And it focuses on seeking thermodynamic relationships among the components so as to find out the energy saving potential of each component by split Exergy analysis. Exergy economic analysis considers the energy conversion system in a physical environment and economic environment. To consider the cost formation of thermodynamics process and its distribution laws. The purpose of it is to obtain the biggest profit as much as possible with the minimum investment cost. The combination of Exergy economics analysis and split theory can provide more comprehensive analysis data for designers.Through the analysis of the results can be seen that the generator should be considered firstly. Turbine own so great avoidable endogenous Exergy damage that should be noticed. For the improvement of the steam turbine system(including generator), must be considered of steam turbine, pump priority. Only improve component mechanical efficiency appropriately, can make other components use more effectively. Then the regenerative system is also worth a big consideration. Each heater is mainly affected by the before heater, It is precisely because the topology of the feed water heater, if only improve one of the feed water heater, this for decreasing contribution of the regenerative system is little impact. Although the boiler system has huge Exergy damage value but can avoidable Exergy destructive only 5%. Finally, consider boiler system. We worth paying attention to the result of Exergy cost analysis of the boiler system is not the biggest in all of the components, on the contrary it is relatively small. That is because the boiler system is located in the front of the energy conversion system. With the thermodynamic cycle process, the fuel costs of component will gradually increase, so the fuel costs of boiler system is less than other components.Traditional Exergy analysis, split Exergy analysis Exergy and economics analysis for this power unit, to reveal Exergy loss distribution, extent and cost efficiency of system components, then optimize them. Carried on the optimization improvement and provided reference for the Supercritical unit and energy saving potentialities. |
