核电厂系统与动力设备：06 第六章 沸水堆(BWR)

1、1,沸水堆 BWR,2,/Public/WorldStatistics/OperationalReactorsByType.aspx,各种堆型的数量和装机容量,3,沸水堆 BWR,掌握BWR的主要结构特点(与PWR相比) 了解BWR的发展状况,主要目的,4,沸水堆,降低了一回路冷却剂水的工作压力，允许一回路冷却水在堆内发生沸腾，并将产生的蒸汽直接送汽轮机发电,5,6,沸水堆结构,压力壳 上顶盖 底部支承 堆芯堆内支承 汽水分离器 蒸汽干燥器 喷射泵,7,沸水堆结构,压力壳 上顶盖 底部支承 堆芯堆内支承 汽水分离器 蒸汽干燥器 喷射泵,8,9,堆芯结构,核

2、燃料组件，控制棒，中子测量探头 核燃料组件： 与压水堆的相同与区别 分区换料,10,燃料组件结构,88正方形栅格 燃料棒 定位棒 流水棒,11,燃料组件结构,12,燃料组件结构,13,燃料组件结构,GE Fuel Rod Fuel Pellet Diameter:1.04 cm Fuel Pellet Height:1.04 cm Fuel Material:UO2 Cladding Diameter (O.D.):1.23 cm Cladding Thickness:0.81 mm Cladding Material:Zircaloy,15,控制棒结构,十字形 炭化硼粉末 控制棒从堆芯底部插

3、入堆芯,Hydraulic Scram System,Hydraulic Scram System,Insert control rods from the bottom of the vessel Control rods are driven by hydraulic mechanism Compressed nitrogen gas provides control BWR control rods are always placed at the bottom of the reactor rather than at the top as in the case of the PWR

4、. The reason is that much of the upper portion of the BWR core is normally occupied by steam voids, and movement of the rods in this region does not have as large an effect on the nuclear reaction as rod motions in the lower, water filed part of the core,Standby Liquid Control System,19,汽水分离器和干燥器,20

5、,喷射泵,再循环流程 功率调节,21,22,沸水堆安全壳,为容纳一回路系统破裂时所释放出来的全部物质，设置了安全壳。 沸水堆一般采用带有蒸汽降压措施的安全壳，如右图所示。抑压水池的热容量很大，事故时能冷凝反匝堆所放出来的蒸汽，又能滞留放射性裂变产物,Reactor Containment,Dry Well: Seals the reactor from the rest of the building Pressure Suppression Pool: Store water for emergency use Containment Shell: Steel shell, a sealed

6、 barrier against radioactive release Reactor Building: Concrete structure, last barrier. Negative pressure is maintained between containment shell and building wall to prevent radioactive release,沸水堆安全壳的演变,Emergency Cooling System,Over Pressure Flow to Suppression Pool High Pressure Injection System

7、 Low Pressure Injection System Containment Spray,Emergency Cooling System,Reactor Control System,Measurements - Computation Integrated containment and reactor buildingimproved seismic response, compact, and easier to construct; Compact reactor buildingless construction material and shorter construct

8、ion times; Optimized modularizationmodule designs refined and proven in real installations; Sophisticated control systemsfully digital, providing reliable and accurate plant monitoring, control, and diagnostics; High integrity fuel, improved water chemistry, and radiation source eliminationreduced r

9、adwaste and occupational exposure,柏崎,ABWR:正在运行的第三代核电技术,TEPCO Kashiwazaki-Kariha NPP, 7 BWR, total 8.21GWe,TEPCO Kashiwazaki-Kariha NPP, 7 BWR, total 8.21GWe,38,ESBWR,G III+ IV,39,ESBWR,40,Passive safety/natural circulation Increase the volume of water in the Vessel Increase driving head Significant reduction in components Pumps, motors,