新型沉降式电站锅炉系统的技术经济分析

针对大容量高参数机组锅炉出现的高度增加、管道增长及阻力损失增大等问题,提出一种新型沉降式电站锅炉设计,使汽轮机平台和锅炉过热器、再热器平台在同一水平面,从而大幅度缩短主蒸汽、再热蒸汽冷段和热段管道长度,对管道长度变化带来的阻力损失、机组热经济性及发电成本的变化进行了分析.结果表明:沉降式电站锅炉的管长明显缩短,当主蒸汽、再热蒸汽冷段和热段的管道长度均减少120m时,电厂热效率提高0.18%,煤耗率降低1.044g/(kW·h),管材初投资减少约6 500万元;以年利用小时取5 294h,煤价为600元/t计算,年节煤6 093t,节约燃料成本约366万元/a,降低发电成本0.28分/(kW·h).

Techno-Economic Analysis of a New Settlement Power Boiler System

To solve the problems existing in large-capacity high-parameter units caused by increased height,lengthened pipeline and increased pressure loss of boiler,a new settlement boiler design was proposed,which makes the turbine platform and the boiler superheater-reheater platform on the same plane,so as to shorten the length of the main steam pipe and the cold/hot segment of reheated steam pipe.An analysis was performed on the variation of the pressure loss,the thermal economy and the cost of power generation resulted from the changes of pipe length.Results show that via the design of settlement boiler,the pipe length can be shortened significantly.When the main steam pipe,the cold segment and hot segment of reheated steam pipe are all shortened by 120 m,the thermal efficiency of the power unit will be increased by 0.18%,while the coal consumption be reduced by 1.044 g/（kW · h）,and the initial investment of pipe material be reduced by 65 million RMB.Based on annual utilization hours of 5 249 h and coal price of 600 RMB/t,the annual coal consumption would be reduced by 6 093 t,meaning the fuel cost would be lowered by 3.66 million RMB/year,and the power generation cost would be reduced by 0.002 8 RMB/（kW · h）.