Magnetic Separation of Alkali-and Alkaline Earth-lon Groups from a Simulated HLLW

在电磁分离技术中，利用铁氧酸盐添加剂将高放废液的组分分成四组，实验研究了以下问题：（1）电磁分离柱中有效填料的选择;（2）共沉淀剂和絮凝剂对溶液中碱土碳酸盐沉淀回收的影响;（3）从模拟高放废液中高回收率回收锶和铯离子的方案：用甲酸将模拟高放废液的2.5M硝酸溶液稀释至pH=1，离心除去沉淀，制备样品溶液。(1)包装材料的选择;测试了三种类型的不锈钢：（a）SUS-410网（0.1 mm丝直径，1* 2 mm网宽），（B）-440球（6 mm直径）和（c）-434卷带（0.1mm厚，0.5mm宽）。之间 ...更多信息 这些钢（C）在对硝酸的耐久性和从溶液中捕集铁素体颗粒的效率方面优于其它钢。这可能是由于在柱中的带边缘处产生的高梯度磁场的巨大贡献。(2)共沉淀剂和絮凝剂：选择镉离子和铁离子分别作为共沉淀剂和絮凝剂。前者在碳酸锶沉淀中没有表现出影响，但后者大大有助于锶的回收率高于97%，而不降低铯的高回收率。(3)分离方案;根据试验结果，提出了以碳酸盐形成为主，结合铁离子絮凝剂和铁酸盐添加剂的运行方案。实验证明，采用sus-434螺旋带电磁过滤柱，从模拟高放废液中分离回收铯锶离子，回收率大于97%。少

On the electromagnetic separation technique, through which the components of a high level liquid waste are partitioned into four gruops with the aid of iron ferrite additives, the following matters have experimentally been examined ;(1) The selection of an effective packing material in an electromagnetic separation column,(2) The effect of coprecipitant and flocculant on the recovery of precipitates of alkaline earth carbonates from the solution, and(3) The scheme by which strontium and cesium ions are recovered at high percentage from a simulated high level liquid nuclear waste.The sample solution was prepared by denitration with formic acid to pH=1 of 2.5M nitric acid solution of a simulated high level liquid waste, and by centrifugation to remove precipitates formed.(1) Selection of packing material ;Three types of stainless steels were tested : (a) sus-410 net (0.1mm wire dia., 1*2mm mesh width), (b) -440 ball (6mm dia.) and (c) -434 coiled ribbon (0.1mm thick., 0.5mm width). Among … More these steel (c) was preferable to others on the durability to nitric acid and on the trapping efficiency of ferrite particulates from solution. This is probably due to the great contribution of a high gradient magnetic field generated at ribbon edges in the column.(2) Coprecipitant and flocculant ;Cadmium ion and ferric ion were chosen as a coprecipitant and a flocculant, respectively. The former showed no effect in the Strontium carbonate precipitation, but the latter greatly contributed to strontium recovery at higher percentage than 97%, without decreasing high recovery of cesium.(3) Separatio scheme ;From the results, the operation shceme was proposed as one which included the carbonate formation, combined with the ferric ion flocculant as well as with iron ferrite additive. The scheme proved effective in mutual separation and recovery of cesium and strontium ions from a simulated high level liquid waste at prcentage higher than 97%, using an electromagnetic filtration column packed with coiled ribbons of sus-434. Less