一种大型纯凝汽轮发电机组对外供热改造新模式

A New Pattern of Large Condensing Turbine-Generator Unit Heat Supply Retrofit

为扩大600MW超临界纯凝机组的供热能力,达到热电联产的要求,研究了提高机组对外供热能力的几种技术措施,提出了退出#1、#2高压加热器,将原一、二段抽汽从再热冷段抽出以达到增大对外供热量的思路,并从对选择性催化还原(selective catalytic reduction,SCR)系统投入的影响、汽轮机高压缸末级叶片安全性、汽轮机轴向推力以及对经济性的影响等方面进行了论证分析,证明该改造模式可行,可供纯凝机组实施大流量低压供热改造时借鉴。

In order to expand the heat supply capacity of 600MW supercritical condensing turbine-generator unit and meet the requirements of combined heat and power production,several technical measures to improve the external heat supply capacity of the unit have been studied.A new pattern on heat supply retrofit was put forward,which is to stop#1&#2 HP heater,and extract the original#1&#2 section steam from cold reheater to increase the quantity of external heating supply.The influences on selective catalytic reduction(SCR),the safety of the last stage blades of the steam turbine,the axial thrust of the steam turbine and the economy were analyzed.It is proved that the method is feasible,worthy for reference when the condensing turbine-generator unit implements large flow low pressure heat supply retrofit.