330MW机组双级低温省煤器系统热经济性分析

Two-stage Low Temperature Economizer Hot Economic Analysis of 330 MW Units

低温省煤器烟气余热利用技术在汽轮机热力系统上的应用,一般都会出现平均传热温差变小、存在低温腐蚀等一系列问题。基于对西柏坡电厂4台330 MW的发电机组,实施双级低温省煤器烟气利用改造技术,并依据能效分布矩阵(EEDM)方程,建立汽轮机辅助汽水系统数学模型。通过3种设计方案的经济性计算分析与比较,设计方案三机组煤耗降低了2.69 g/(k W·h),效率由未引入低温省煤器系统的47.35%提高至48.16%,每台机组每年可节约119.52万元,二氧化碳排放量每年可减少18 322.90 t。结果表明,方案三中提出的双级低温省煤器系统在减少煤炭消耗、降低经济成本等方面都优于方案二常规低温省煤器系统,具有明显的经济效益和环境效益。

The technology of flue gas waste heat utilization of low temperature economizer in the application of steam turbine thermal system generally arises a series of problems, such as the decrease average heat transfer tem- perature difference, low temperature corrosion, etc. The transformation technology of flue gas waste heat utilization of two-stage low temperature economizer is used in the four units of 300 MW generating set of Xibaipo Power Plant. Besides, according to the energy efficiency distribution matrix （EEDM） equation, the mathematical model of auxiliary steam-water system of steam turbine is established. The results show that the unit coal consumption of third project is reduced 2.69g/ （ kW· h） and its efficiency is increased from 47.35 % , which is not equipped low temperature economizer, to 48.16% by calculating and comparing the economical efficiency of three different design projects, each unit can save 1. 1592 million Yuan per year. The CO2 emission can be reduced by 18322.9t each year. The results show that the two-stage low temperature economizer of the third project is superior to the conven- tional low temperature economizer of second on the aspects of reducing coal consumption saving cost, etc. In con- clusion, the third project has high performance on the aspects of economy and environment.