高温熔盐试验回路系统设计及验证研究  

Design and Test Study on a High Temperature Molten Salt Loop

作　　者：孔祥波[1,2] 王纳秀 林良程[1] 陆惠菊[1] 傅远[1] 王晓[1] Kong Xiangbo;Wang Naxiu;Lin Liangcheng;Lu Huiju;Fu Yuan;Wang Xiao(Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai,201800,China;Univerisity of Chinese Academy of Sciences,Beijing,100049,China)

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100049

出　　处：《核动力工程》2020年第5期127-131,共5页Nuclear Power Engineering

基　　金：中国科学院战略性先导科技专项资助项目(XDA02001005)。

摘　　要：钍基熔盐堆核能系统(TMSR)计划建设热功率2 MW的液态燃料熔盐堆。在熔盐泵、换热器、冷冻阀等设备原理样机研制基础上,需要设计并建造高温氟盐回路对上述设备进行运行考验。首先设定熔盐-空气换热器换热功率为200 kW,根据经典热量方程及预定流速法确定系统流量为15 m^3/h、管径为DN50(公称直径为50 mm)。采用Fluent数值计算确定系统压损为155 kPa,考虑一定裕量后熔盐泵扬程确定为20 m。为解决管道在高温工况下热应力集中问题,除熔盐泵固定安装外,加热器及换热器设计采用了万向球移动支承结构以增加系统柔性。自建成以来,回路累计运行超过4000 h,相关设备及系统结构设计得到验证。系统实际压损为110~120 kPa,仍需采用差压计进行实测验证。熔盐杂质含量分析表明,系统运行后Cr、Mo等杂质元素含量提高了2个数量级,说明存在材料腐蚀。回路内水氧含量控制水平需要在100μL/L设计限值基础上进一步提高。The Thorium Molten Salt Reactor(TMSR)project plans to construct a 2 MWt liquid fuel molten salt reactor.After successful R&D of the proto-type equipment like pump,heat exchanger and freeze valve,construction of a high temperature fluoride loop is designed and constructed to test them.The rated power of heat exchange is designed to be 200 kW,and the flow rate is set as 15 m^3/h by the caloric equation.Hence the pipe caliber chose to be DN50.The numerical computation by Fluent revealed that the pressure drop of the loop system is about 155 kPa,and the overdesign of the pump head is set as 20 m accordingly.To avoid thermal stress concentration of the pipeline,both the electric heater and radiator are designed to be fixed on a flexible universal sphere support,except the pump which is anchored on steel support directly.The structural design of the equipment and the loop hase been verified by several tests with an accumulated operating time near 4000 hours.The actual pressure drop of the loop is about 110~120 kPa,which still needs to be accurately measured by differential manometer in future.The analysis of the impurity of the molten salt shows that the contents of Cr and Mo increased by two orders of magnitude after loop operation,which means that an obvious material corrosion occurs.The level of moisture and oxygen,which is the main reason that cause fluoride corrosion,should be controlled considerably lower than the original design level of 100μL/L.

关 键 词：熔盐堆 回路系统 结构设计 运行考验 

分 类 号：TL353[核科学技术—核技术及应用] TL426