一种优化型双背压低真空供热系统及关键问题论证

An Optimized Low Vacuum Heating System with Double Back Pressure and its Key Problems

我国北方地区尤其是东北地区,燃煤供热机组装机占比高。在火电行业“三改联动”背景下,提高燃煤供热机组的灵活性尤为重要。以国家能源局首批供热灵活性改造试点项目、某电厂2号机组双背压低真空供热灵活性改造为例,针对现有技术方案存在的不足,基于非能动设计理念,提出了优化方案。并对所提方案中的关键问题如联络管通流能力、水位调节阀选型、流体闪蒸影响及控制策略等进行了必要的计算及论证。结果表明:基于本文的改造方案,联络管通流能力达到10198t/h,水位调节阀选型CV值为2833,流体闪蒸比例为4.7%,系统人为控制环节明显减少,优化方案具有技术可行性及更好的技术经济性。

The installed proportion of coal-fired heating units is very high in the northern regions of China,especially in the northeastern region.In the context of the"three reforms and linkage"in the thermal power industry,improving the flexibility of coal-fired heating units is particularly important.This paper takes the double back pressure low vacuum heating transform of the one power plant unit 2 an example,which is in the first batch of flexibility renovation pilot projects of the National Energy Administration.In response to the shortcomings of existing technical solutions,based on the concept of passive design,an optimization plan is proposed.Necessary calculations and detailed demonstrations were conducted on key issues such as the flow capacity of the connecting pipe,the selection of water level control valves,the impact of fluid flashing,and control strategies.The results show that the flow capacity of the connecting pipe reaches 10198t/h,the CV value of the water level control valve selection is 2833,and the fluid flash ratio is 4.7%.The artificial control links of the system are significantly reduced,and the optimization plan has technical feasibility and better technical and economic efficiency.