| So far supercritical pressure circulating fluidized bed boiler with vertical furnace walls is still at the stage of feasibility in the world. Our country has still not done this research. This project is doing some prophase investigation on the supercritical pressure circulating fluidized bed boiler. This project is aiming tofollow the update progress of the world.The technical feasibility, thermodynamic effectiveness and the engineering problem of supercritical pressure circulating fluidized bed boiler with vertical furnace walls was analysed in this thesis. The present investigation sows that CFB is more suitable than PC boiler under the condition of supercritical pressure. The concept design of supercritical CFB was done in present research. And a hydrodynamic model of supercritical CFB was built. Combined the real testing data, the paper developed a calculation program of water wall temperature and pressure drop for designed supercritical pressure CFB boiler with vertical water walls. The hydrodynamic calculation and safety checkout under five loads was carried out. This program can predict the wall temperature,internal wall heat tranfer coefficient,fluid temperature and entropy profile along the water wall. All of these provide an important foundation for designing this type of water wall structure to ensure the safety of the boiler operation. This hydrodynamic calculation program and the results can be used to analyze operation reliability and structure design of water wall system.The calculated results indicate that the design of supercritical pressure CFB under supercritical pressure is possible. For 600MW CFB boiler, the extra investigation for supercriticalization of it can be reclaimed within 10 years. The designed boiler has steady operation situation, with rational framework and boiler heating surface. Water walls have sufficient flux under calculated 5 loads. DNB do not occur under these loads. The maximal temperature difference occurs on MCR is within 18℃.
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