汽轮机低真空供暖系统的优化与实践

Optimization and Practice of Low Vacuum Heating System for Steam Turbine

本钢板材发电厂33号机采用低真空供暖,供暖形式为循环水通过4台板式换热器对热网回水进行加热。为了满足供暖需求,真空在-70 kPa左右、排汽温度在70℃左右,该工况若长时间运行,则会造成凝汽器铜管与管板之间胀口松脱,影响机组安全稳定运行。为此将凝汽器改造为热网凝汽器,即非采暖期凝汽器将汽轮机乏汽冷凝,回收凝结水;采暖期凝汽器直接作为热网换热器,为热用户提供余热水。

The No.33 units of power plant of Bensteel Sheet Co.,Ltd.uses low-vacuum heating in the form of that circulating water heats the return water of the heat network through four plate heat exchangers.In order to meet the heating demand,the vacuum is around-70 kPa and the discharge steam temperature is around 70°C.If this condition is kept running for a long time,it will cause the condenser copper tubes to loosen from the tube plate,which will affect the safe and stable operation of the unit.For this reason,the condenser is converted into a heat network condenser,in other word,the condenser condenses the turbine exhaust steam in the non-heating period and recovers the condensate;while the condenser is directly used as a heat network heat exchanger in the heating period to provide residual hot water for the heat users.