摘要
为了降低燃煤机组资源消耗实现燃煤机组烟气余热和水回收,本文采用MATLAB软件建立某330 MW燃煤机组烟气余热和水回收系统仿真计算模型,计算结果表明:利用烟气换热器回收烟气余热的同时将脱硫塔之后的烟气冷却,可回收冷凝水8.68 kg/s,同时也会产生33.95 MW冷凝热量。为利用冷凝热量,本文提出热泵供热方案(方案1)和预热空气方案(方案2),方案1将冷凝热量作为压缩式热泵冷源,当供热温度为75℃时,热泵耗功11.80 MW,对外供热45.75 MW;当供热温度为100℃时,热泵耗功17.37 MW,对外供热51.32 MW;方案2利用冷凝热量驱动暖风器在低温环境预热空气,替代蒸汽暖风器。环境温度-20,-10和0℃时,方案2节煤率分别为3.60,2.71和1.81 g/(kW·h)。当环境温度逐渐升高时,方案2节煤率下降,但是系统部分状态点温度升高,低温省煤器的节煤率也逐步增加,方案2有较好的节能潜力。
In order to reduce the resource consumption of coal-fired power plants and realize the flue gas waste heat and water recovery, the simulation calculation model of a flue gas waste heat and water recovery system of 330 MW coal-fired power plant is established by MATLAB software.The calculation results show that the flue gas heat exchangers are installed to recover the flue gas waste heat and cool the flue gas after desulfurization, which can recover the condensate water of 8.68 kg/s, meanwhile, the condensation heat of 33.95 MW will be produced.In order to utilize the condensation heat, the heat pump heating scheme(scheme Ⅰ) and preheating air scheme(scheme Ⅱ) are proposed in this paper.SchemeⅠuses the condensation heat as the cooling source of compression heat pump.When the heating temperature is 75 ℃, the heat pump consumes the electric power of 11.80 MW and produces the heat of 45.75 MW.When the heating temperature is 100 ℃, the heat pump consumes the electric power of 17.37 MW and produces the heat of 51.32 MW.In schemeⅡ, the condensate heat is used to preheat the air in the pre-air pre-heater(PAPH) instead of the steam air heater.When the ambient temperatures are-20,-10 and 0 ℃, the coal saving rates of schemeⅡ are 3.60, 2.71 and 1.81 g/(kW·h), respectively.As the ambient temperature increases, the coal saving rate of scheme Ⅱ decreases, and the temperatures of some system state points increase, which leads to the gradual increase of the coal saving rate of the low-temperature economizer.Therefore, Scheme Ⅱ has better energy-saving potential.
作者
张钧泰
张国柱
杨凯旋
刘明
ZHANG Jun-tai;ZHANG Guo-zhu;YANG Kai-xuan;LIU Ming(Datang Environment Industry Group Co.,Ltd.,Beijing,China,100097;State Key Laboratory of Multiphase Flow in Power Engineering,Xizan Jiaotong University,Xizan,China,710049)
出处
《热能动力工程》
CAS
CSCD
北大核心
2022年第5期131-136,共6页
Journal of Engineering for Thermal Energy and Power
基金
国家重点研发计划(2018YFB0604303)。
关键词
燃煤机组
水回收
余热利用
coal-fired power plants
water recovery
waste heat utilization
