电站锅炉烟气余热利用技术方案研究

超临界电站锅炉排烟热损失量很大，对锅炉尾部烟气余热进行回收利用可以有效提高电厂的热经济性，减少煤耗，降低环境污染。目前火电厂最广泛提高烟气余热利用效率的方式是加装低温省煤器装置。对某超临界机组锅炉余热利用技术进行研究，分析不同低温省煤器布置方案，提出采用双级低温省煤器回收电站锅炉余热利用技术方案，即采用低温烟气与低加凝结水换热技术、前置式空气预热器与低温省煤器组合的能源梯级利用方式，实现最优节能及最佳投资收益。

Study on Technical Scheme of Flue Gas Waste Heat Utilization in Utility Boiler

The exhaust heat loss of supercritical power station boilers is very large. Recovery and utilization of waste heat from boiler can effectively improve the thermal economy of power plants, and reduce coal consumption and environmental pollution. At present, the way most widely used to improve the utilization efficiency of flue gas waste heat in thermal power plants is to install low temperature economizer. The waste heat utilization technology of a supercritical unit boiler was studied, different low-temperature economizer layout schemes were analyzed, and a technical scheme for recovery of waste heat from power plant boiler by using dual-stage low-temperature economizer was proposed, i.e., the combination of low-temperature flue gas and low-condensation water heat exchange technology, the energy of front air pre-heater and low-temperature economizer. The source cascade utilization mode can achieve optimal energy saving and optimal investment return.