The Research Of Life Loss Of Badaling Solar Thermal To-wer Power Plant’s Superheater In The Process Of Temp-erature And Pressure Rising

In recent years, solar thermal power generation technology has become a hot topic in the field of renewable energy all over the world, counties are actively developing their own solar thermal power generation enterprise. In order to explore the low-cost, commercial and large-scale technical approaches of the solar tower thermal power generation, Ministry of science and technology has established the key projects-"the solar thermal power technology and system demonstration" during the period of the "Eleventh Five-Year", and the first solar tower thermal power plant in China-Badaling solar tower thermal power plant has been constructed by the Chinese Academy of Sciences Institute of Electrical Engineering.The heat absorber of the Badaling plant is cavity heat absorber, which can transform the light energy into thermal energy and heat the water to become superheated steam, and it is a key component of the plant, its life and running performance directly affects the plant’s safety and operating efficiency. Due to the alternation of day and night, the weather change and the presence of clouds, the solar absorber must experience more frequent shutdown process than the conventional power station boiler. Unlike conventional boiler, the superheater and evaporating heating surface (equal to the boiler’s water wall) of cavity absorber are arranged in the same chamber, so their external environment is almost the same with high temperature. While heating and pressure boosting during the absorber start stage, less saturated steam is generated in the drum, the cooling effect to the surperheater is extremely limited. Therefore, it is necessary to study the absorber life loss during the heating and pressure boosting stage.The paper caculated the mechanical stress, which caused by the pressure in the pipes, in the superheater by using the elastic theory. According to the working principles of the, the paper established transient fomulations and the boundary conditons of the superheater. By discreting and caculating the fomulations, the temperature distribution of the superheater was obtained. The toroidal stress which caused by the tempetature difference was obtained by the the theory of thermoelastic theory. Base on the computation method of TRD301and the Robinson rule, the paper caculated the superheater in the absorber of the Badaling solar tower thermal power plant fatigue life loss and creep life loss during the heating and pressure boosting process. The conclusions have certain guiding signficance on the protection of the superheater during the heating and pressure boosting process.