【作者】 刘强；

【导师】 李斌； 鲁文恭；

【作者基本信息】 华北电力大学 ， 工程硕士（专业学位）， 2017， 硕士

【摘要】 为了彻底解决机组排烟温度过高的问题,提高机组效率、推进节能减排,上都电厂三期2×660MW机组在锅炉尾部受热面增设低温省煤器。本文以设计数据和现场实际情况为基础,对低温省煤器的改造进行可行性分析。分别对工程概况、机组现状进行了介绍,提出了三种改造方案,对改造中需要解决的技术难点进行了分析,并提出相关解决方案;对三种方案投资成本、工程造价进行计算,并利用等效焓降法对其经济收益及环保收益进行了分析评估。结果表明,本项目增设暖风器系统及低温省煤器系统,从7号低加入口与出口混合至80℃取水加热二次风暖风器,将空预器入口二次风温提高至45℃,出口一次风温为45℃。由于空气预热器进口风温升高至45℃,排烟温度由160℃降低到95℃;低温省煤器从7号低加入口与出口混合至70℃取水,6号低加出口121.9℃回水,受热面全部采用ND钢制作。经过计算,方案一的经济效益和环保效果最佳。方案一可降低发电煤耗约3.61g/kW·h,年节省标煤10483吨,年节煤收益345.95万元,年节水量43.3万吨,年节水收益177.78万元,年总收益523.73万元,单台机投资2619.9万元,两台机总投资5239.80万元。增设低温省煤器后,机组污染物排放降低,环保效益显著。因此,增设低温省煤器可行。更多还原

【Abstract】 In order to solve the problem of high flue gas temperature,improve the efficiency of the unit,promote energy saving and emission reduction,the low temperature economizer is installed on the heating surface of the boiler rear end on 2×660MW units of the third-stage project in Shangdu power plant.Based on the design data and the actual situation of the site,this paper analyzes the feasibility of the low temperature economizer retrofit.Introduce the project overview and states,provide three kinds of retrofit ways,analyze the technical difficulties in the retrofit,and put forward relevant solutions.Calculate the investment cost and the project cost,and its economic benefits and environmental benefits were analyzed and evaluated by the equivalent enthalpy drop method.The results show that the project installs air heater and low temperature economizer system,the water will be mixed from 7# low pressure heater inlet and outlet to 80℃ to heat the secondary air,improve the temperature of air preheater inlet secondary air to 45℃,the temperature of the primary air outlet is 45℃.Because of the air preheater inlet temperature rises to 45℃,the flue gas temperature is decreased from 160℃ to 95℃,low temperature economizer from 7# low pressure heater inlet and water outlet mix to 70℃,the backwater temperature from 6# low pressure heater outlet is 121.9℃,the heating surfaces will be made by ND steel.Through calculation,the economic benefit and environmental protection of program 1 is the best.The program 1 can reduce the coal consumption of about 3.61 g/kW·h,annual save standard coal about 10483 tons;annual coal revenue 3.46 million yuan;annual save water volume of 433 thousand tons;annual save income 1.77 million yuan;the total annual income of 5.23 million yuan.The investment cost of each unit is 26.19 million yuan,two machines with a total cost of 52.39 million yuan.After installing the low temperature economizer,the discharge of pollutants of the unit is reduced and the environmental protection benefit is remarkable.Therefore,installing the low temperature economizer is feasible.更多还原