Study On Start-up Optimized Schemes Of600MW Supercritical Coal-fired Units And Its Economic Evaluation

In response to Chinese government’s commitment on “by2020, China’s carbondioxide emissions per unit of GDP will be reduced by40percent to45percent from the2005level”, and implement the strategic planning of energy-saving priority which isclearly made in the Chinese energy development strategy. Aiming at currently domestic600MW supercritical coal-fired unit’s extensive(large consumption large emission) start-up,this article taking the plant’s Unit1and2as the research object, proposes energy savingoptimized schemes, analyses its feasibility, designs the schemes and calculatesenergy-saving benefit obtained from optimization.600MW supercritical coal-fired unit’s start-up process is mainly divided into boilerchemical cleaning, boiler ignition, temperature rising and pressure increasing, turbinerunning and generator grid-connected and so on. Generally, unit’s is started up by themanufacturer recommending start-up curve and the related parameters, which are givenbased on experience, even some of which are given in order to be easily operated by powerplant’s operating personnel.(ignoring the consumption of unit’s start-up). In thedevelopment of creating the energy-saving environmental friendly enterprise and powerplant’s strengthening the cost control, the original start-up mode is bound to be changedand optimized. In this paper, we propose and research three energy-saving optimizedschemes focusing on electricity saving, water saving and fuel saving: TDBFP replacingMDBFP as start-up feedwater pump, startup feedwater flow’s reduction and theenergy-saving control of HP bypass valve, and then make its’ economic evaluation.