自然安全的BREST铅冷快堆——现代核能体系中最具发展潜力的堆型

Lead-cooled Natural Safe Fast Reactor BREST——the most Potential Reactor in the Modern Nuclear Power System

目前投运核电厂主要采用热中子反应堆,其共同的欠缺有两点:一是天然铀的有效利用率只有1%左右;二是其乏燃料包含半衰期极长的裂变产物。只有在快中子能谱范围内,天然铀才能得到最良好的利用,长半衰期超铀元素的裂变截面大于其吸收截面,可在快堆中用作核燃料或被嬗变。因此,为了使核能真正成为国家能源体系的主要支柱,快中子增殖堆是其不可或缺的重要组成部分。目前人类面临的能源保障及环保双重压力,正催促快堆的加速发展。近20年的研究成果表明,铅冷快堆是最具发展潜力与现实性的堆型。本文全面分析了铅冷快堆的自然安全性能,并推荐采用具有完全非能动安全冷却系统的压水堆与铅冷快堆组合成自然安全且立足于现有成熟技术的核能体系,全面满足对现代核能提出的各项要求,为人类社会可持续发展提供无时限的大规模清洁能源保障。

Almost all reactors in present nuclear power stations are thermal nutron reactors, thy have their common shortcomings, that is the first, natural uranium effective utilization ratio is only less than one procent, and the second, burying large quantities of radioactive spent fuel for more than a handred of thounsands years in the case of using open fuel cycle. All U-238 gradually converted into fissionable Pu-239 after nutron absobtion,long-lived radioactive MA can be used as a fuel or be transmutated,all these processes can be accomplished only in fast nutron reactors, so FR is an indispensable important component in modern nuclear power system. The SFR and LFR are compared comprehensively in the paper and the result shows that LFR BREST is provided withthe most development potential and reality,it is a naturally safe FR with nitride fuel and lead coolant , （usiong this combination have achived CBR little more than one）, and a special onsite closed fuel cycle.The optimum combination , consisted of LFR BREST and PWR nuclear power station with AAP （advanced all passive） safety cooling systems, forms united nuclear fuel cycle system and enable to meet all requirements of modern nuclar power system, so make a practical contribution to the construction of the modern energy system in China.