9E联合循环机组余热锅炉节能优化改造研究

Energy-saving retrofit for a waste heat boiler of 9E gas-steam combined cycle unit

以9E联合循环机组设计燃用重油,实际燃用天然气为降低余热锅炉排烟温度为例,计算分析增加主蒸汽流量发电,增加中压蒸汽受热面供热,或者直接在余热锅炉尾部布置给水预热装置以供应低温热水这三种方案的理论可行性及经济性,指出受低压蒸发器的节点温差限制,同时为保证热力除氧系统的正常工作,目前系统只能在尾部布置给水预热装置。

Taking the design of 9E combined cycle unit for burning heavy oil and the actual burning of natural gas as an example to reduce the exhaust gas temperature of waste heat boiler,this paper calculates and analyses the theoretical feasibility and economy of three schemes:increasing the main steam flow,increasing the heating surface of mediumpressure steam,or directly arranging the feed water preheating device at the tail of waste heat boiler to supply lowtemperature hot water,and points out the node temperature difference of low-pressure evaporator.At the same time,in order to ensure the normal operation of the thermal deaeration system,at present the system can only arrange the feed water preheating device at the tail.