基于凝汽器分区理论的湿冷式电厂循环水余热回收技术

通过数值模拟计算手段对某电厂凝汽器新增一组高效传热管束,用以回收利用凝汽器排放的余热。在满足夏季工况机组真空度考核要求下,在冬季抽汽供热工况下机组背压为4.9kPa和电功率分别为280/250MW时,计算确定在不同环境气温下的机组供热能力并确定相应的凝汽器分区运行方式。电厂试验表明,相对于对现有的凝汽器进行分区改造方式,在凝汽器新增设计高效换热区回收乏汽余热,可以获得较高温度的余热能,运行方式更加灵活,经济和社会效益显著。在非供热工况,凝汽器新增管束的投切对机组真空度的影响不大,可以满足夏季机组真空度考核要求。

Recycling Technology of Waste Heat from Circulating Water in Wet-cooled Power Plant Based on the Theory of Condenser Zoning

A new set of high efficiency heat transfer tube bundle was added to the condenser of a power plant unit to recover and utilize the waste heat of the condenser by means of numerical simulation. Under the condition of meeting the requirement of power plant unit vacuum assessment in summer, the unit heating capacity under different ambient temperatures and the corresponding condenser zoning operation mode were determined when the unit back pressure is 4.9 kPa and the electric power is 280/250MW respectively under winter rated extraction heating mode. The power plant test shows that the new design of high efficiency heat exchange zone for recovery of waste heat in condenser can obtain higher temperature waste heat energy, more flexible operation modecompared with the existing regionalized reformation of condenser , whichhas remarkable economic and social benefit. In non-heating conditions, the switching of the added tube bundles of condenser has little effects on unit vacuum, which can meet the requirements of unit vacuum assessment in summer.