核电厂泵房海水系统问题分析与改进

Analysis and Improvement of the Seawater System in the Pumping Station of Nuclear Power Plant

核岛及常规岛工艺系统在正常运行时将产生大量的热负荷,需要冷却水进行换热,以带走设备运行产生的热量,避免设备电机温度过高或管道内介质温度异常,导致设备损坏、系统运行故障。核电厂泵房海水系统的主要功能是向核岛设备冷却水系统、常规岛凝汽器及辅助冷却水系统提供必需的冷却水(海水),从而带走冷却水系统收集的热负荷排向最终热阱(大海)。泵房海水系统不仅是核电厂安全运行的重要保障,也是凝结水泵、主给水泵、安注泵、安喷泵等设备单体试验、系统调试的必要条件。它包括重要厂用水系统、循环水系统及循环水过滤系统。本文结合巴基斯坦卡拉奇核电厂K-2机组泵房海水系统在安装及调试阶段发生的典型问题,对问题产生的原因进行了分析,围绕如何提高管道质量、优化施工方法等方面进行探讨。通过采取合理的改进措施,提出了提高管道预制质量、前置条件优先施工、设计阶段材料优化的合理化建议,保证了泵房海水系统的可靠运行。本文的经验总结及改进措施能对后续核电工程提供良好的指导借鉴作用。

Nuclear and conventional island process systems will generate a large amount of heat load during normal operation,requiring cooling water for heat exchange,so as to take away the heat generated by equipment operation and avoid equipment damage and system operation failure due to excessively high motor temperature or abnormal medium temperature in the pipeline.The main function of the seawater system in the pumping station of nuclear power plant is to provide the necessary cooling water(seawater)for the component cooling system of the nuclear island,and the condenser and auxiliary cooling water system of the conventional island,the heat load collected by the cooling water system is discharged to the final heat trap(ocean).The seawater system of the pumping station is not only an important guarantee for the safe operation of nuclear power plant,but also a necessary condition for the test of individual equipment and system commissioning of the condensate pump,feedwater pump,safety injection pump,and containment spray pump.It includes the essential service water system,circulating water system,and circulating water filtration system.Based on the typical problems of the seawater system in the K2 pumping station of Pakistan Karachi NPP project during installation and commissioning,this paper analyzes the causes of the problems,how to improve the pipeline quality and optimize construction methods.By taking reasonable improvement measures,some reasonable suggestions are put forward to improve the prefabrication quality of pipelines,give priority to the construction of preconditions,and optimize the materials in the design stage,so as to ensure the reliable operation of the seawater system in the pumping station.In this paper,experience summary and improvement measures can provide good guidance and reference for the follow-up nuclear power projects.