Study On Double-rotor And High-Back-Pressure Heating Scheme And Economy Of A 300MW Unit

Cogeneration central heating is an important measure for energy saving and emission reduction in power generation industry.China's central heating cogeneration has experienced a small boiler room heating,small cogeneration unit heating,large and medium-sized pumping condensate-type transformation of heating,the double-rotor and high-back pressure retrofitting of the current heating scheme is the popular thermal power supply thermal scheme.In this paper,the technical scheme of double-rotor and high-back-pressure heating for 300 MW unit is studied,and the scheme of turbine low-pressure cylinder,condenser and corresponding auxiliary system is analyzed and proved,and the safety of unit thermal expansion,vibration and bearing elevation,The double rotor high back pressure is feasible in the transformation technology.From the supply and return water temperature diagram,this paper divides the heating period into three typical working conditions: the initial heat ing stage,the secondary cold period and the severe cold period,and replaces the whole heating period to the double-rotor and high-back-pressure heating scheme with three working conditions.The economic benefit and coal saving and emission reduction of d ifferent heating area are calculated and analyzed.Contrast the double-rotor and high-back-pressure scheme with the heat pump scheme,the double-rotor and high-back-pressure scheme can achieve higher economic benefits.The double-rotor and high-back-pressure scheme is optimized again in the space domain.The hot users are divided into heating near users and heating far users.The users in the near heat supply heat with small temperature difference and large flow.The users in the far heat supply heat with large temperature difference and small flow.Taking the net income as the objective function,the optimum heat distribution distance is studied.