Optimization and influence factors analysis of auxiliary system waste heat utilization process for oxy-fuel combustion power generation unit
Based on the idea of multi-system integration and heat coupling,combined with the energy level optimal matching principle,the flow adjustable waste heat cascade utilization scheme of the auxiliary system with series and parallel mixed structure is designed for the oxy-fuel combustion power generator unit.Using the analysis and calculation method of efficiency-number of heat transfer unit(e-NTU),the calculation formula of interstage cooler outlet exit gas and condensed water temperature is derived.Based on the characteristic parameters of the internal heat transfer process of the steam turbine regeneration system,the heat-power conversion coefficient matrix equation of the steam turbine regeneration system is built,and the calculation model of power generation increment in the auxiliary system waste heat utilization process is established on this basis,which can quantitatively calculate the impact of the waste heat utilization process on the unit power generation.Taking a 350 MW oxy-fuel combustion simulation power generation unit as an example,overall considering the influence of the waste heat utilization process of the auxiliary system on the auxiliary system operation energy consumption and power generation of the unit,and setting the maximum net increment of generation power as the optimization objective,the optimal value of condensate water flow during the waste heat utilization process is determined.After optimization,the power generation net increment of the oxy-fuel combustion power generation unit increases by 7.09 MW,the power supply standard coal consumption decreases by 11.68 g/(kW h),and the power supply efficiency increases by 1.68％.Moreover,the effect of the unit load variation and different kinds of coal on the auxiliary system waste heat utilization process is further analyzed.
NETL
NSTL
万方数据
