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为评价已建立的裂变~(99) Mo分离纯化工艺,即AgNO3沉淀法、α-安息香肟沉淀法、阴离子交换色层法与活性炭色层法联用工艺流程,对放射性碘的去除效果,本研究以~(131)I为放射性示踪剂,研究两种不同放射性碘化学形态~(131)I~-与~(131)IO_3~-在~(99) Mo分离纯化工艺中的行为及其去除效果。结果表明,对于~(131)I~-,AgNO3沉淀能够去除模拟溶液中98.2%~(131)I~-,α-安息香肟沉淀法分离~(99) Mo工艺能够去除97.9%~(131)I~-,AG1-×8树脂上阴离子与I~-发生交换可以除去Mo样品中~(99).9%的~(131)I~-,活性炭色层法通过吸附作用除去75%的~(131)I~-,最终~(131)I~-的累积去污系数为1.90×106,~(131)I~-的去除率大于~(99).~(99)%。对于~(131)IO_3~-,加入AgNO3对其去除没有影响,ɑ-安息香肟沉淀法能除去~(99)%以上的~(131)IO_3~-,AG1-×8树脂上阴离子与~(131)IO_3~-发生交换可以除去Mo样品中~(99).9%的~(131)IO_3~-,活性炭色层法能除去约70%~(131)IO_3~-,最终~(131)IO_3~-的累积去污系数为2.52×105,~(131)IO_3~-的去除率大于~(99).~(99)%。已建立的裂变~(99) Mo分离纯化工艺流程对~(131)I~-与~(131)IO_3~-均具有出色的去除效果。 相似文献
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核电厂低中放废树脂处理工艺 总被引:3,自引:0,他引:3
介绍了核电厂废树脂的来源,阐述了废树脂需要稳定化处理的必要性。对核素分离法、水泥固化法、氧化分解法、高完整容器、热态超级压缩法等工艺进行了分析比较,对废树脂的热态超级压缩工艺的成熟性和规范性进行了讨论。 相似文献
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中国近30年的快速发展对环境造成了严重破坏,尤其是对水资源的破坏,严重威胁着生态平衡及人类健康。工业含油/可溶性高毒废水是水净化过程中亟需解决的问题,然而,制备能够同时实现油水分离和降解有机物污染物的材料仍然是一个严峻的挑战。本研究制备了耐久型β-FeOOH纳米棒/聚酯织物复合材料,用于解决上述问题。实现在对油/水混合物进行分离的同时,将水中可溶性有机物原位降解的双重净化效果。实验结果表明,油/水分离效率及对水中高毒、可溶性有机物的去除率分别达到99%及90%以上;材料经过多轮循环降解实验和加速洗涤试验后,油/水分离效率和有害有机物的去除率仍保持基本不变。 相似文献
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介绍了CO2+O2地浸采铀和酸法地浸采铀的水冶回收工艺,依据新疆某地浸铀矿山的铀矿水冶工艺现状,提出将CO2+O2地浸采铀工艺下饱和树脂纳入酸法地浸水冶回收系统进行处理的酸化工艺。分析了CO2+O2浸出工艺下碳酸铀酰型饱和树脂的酸化转化机理,开展了以酸法水冶系统中淋洗剂、转型剂、洗涤合格液为酸化剂的搅拌浸泡试验。结果表明,酸法水冶系统中的洗涤合格液是符合工艺要求的酸化剂,可充分利用洗涤合格液中的剩余酸度对碳酸铀酰型饱和树脂进行转化,并将转化后树脂对铀的吸附容量由74.71 g/L提高至76.73 g/L,实现了与酸法水冶系统再饱和树脂的共同淋洗和转型。 相似文献
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99 Tc是核电站运行过程中产生的裂变产物之一,是一种具有较高裂变产额的长寿命放射性核素,易在环境中迁移,因此高放废液中锝的分离对于核废料后处理具有重要意义。以铼模拟锝,通过静态实验和动态实验研究了AR-01树脂对铼的吸附和解吸行为,主要考察了温度、酸度、时间等因素对AR-01树脂吸附性能的影响,并通过还原解吸法探讨解吸条件。结果表明:AR-01树脂吸附铼的反应为放热反应,酸度提高,吸附效率降低,在流速1.0mL/min下,树脂的动态饱和吸附容量达到105mg/g,解吸剂中加入还原剂SnCl2提高了解吸效率,树脂具备很好的重复利用性。以上结果为AR-01树脂应用于高放废液中锝的吸附分离提供了参考。 相似文献
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《核动力工程》2019,(Z2)
池式鼓泡过滤是核电厂严重事故条件下一种重要的放射性气溶胶滞留过程。本文针对可溶性气溶胶在鼓泡过滤条件下的去除特性开展实验研究。结果表明,可溶性气溶胶会在鼓泡过滤过程中吸湿增长,尺寸增大,因此在评价可溶性气溶胶的去除效率时,必须保证上下游气溶胶处于干燥状态;另外,可溶性气溶胶的吸湿增长使得气溶胶的沉降特性发生改变,主要表现为原处于布朗扩散主导区的小粒径气溶胶会进入最易穿透区,效率降低,而原处于最易穿透区的气溶胶会进入惯性主导区,效率增加;气体流量的变化对气溶胶去除效率的影响不是单调的,与气-液两相流型以及气泡行为密切相关。实验结果可为验证和完善池式过滤气溶胶模型提供数据支撑。 相似文献
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为评价已建立的裂变99Mo分离纯化工艺,即AgNO3沉淀法、α-安息香肟沉淀法、阴离子交换色层法与活性炭色层法联用工艺流程,对放射性碘的去除效果,本研究以131I为放射性示踪剂,研究两种不同放射性碘化学形态131I-与131IO-3在99Mo分离纯化工艺中的行为及其去除效果。结果表明,对于131I-,AgNO3沉淀能够去除模拟溶液中98.2%131I-,α-安息香肟沉淀法分离99Mo工艺能够去除97.9%131I-,AG1-×8树脂上阴离子与I-发生交换可以除去Mo样品中99.9%的131I-,活性炭色层法通过吸附作用除去75%的131I-,最终131I-的累积去污系数为1.90×106,131I-的去除率大于99.99%。对于131IO-3,加入AgNO3对其去除没有影响,ɑ-安息香肟沉淀法能除去99%以上的131IO-3,AG1-×8树脂上阴离子与131IO-3发生交换可以除去Mo样品中99.9%的131IO-3,活性炭色层法能除去约70%131IO-3,最终131IO-3的累积去污系数为2.52×105,131IO-3的去除率大于99.99%。已建立的裂变99Mo分离纯化工艺流程对131I-与131IO-3均具有出色的去除效果。 相似文献
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废水组分对离子交换树脂处理含铀废水的影响 总被引:2,自引:1,他引:1
采用静态吸附和动态柱式实验相结合的方法,研究含铀废水中其它组分对201×7强碱性阴离子交换树脂处理含铀废水工艺过程除铀性能的影响。实验结果表明:溶液中存在的常量阴离子、三乙醇胺和机油等不同程度影响树脂的交换效率或降低树脂的工作交换容量。当溶液中c(CO2-3)≥0.24mol/L、c(HCO-3)≥0.28mol/L、c(SO2-3)≥0.23mol/L、c(Cl-)>0.09mol/L时,出水铀质量浓度大于20μg/L;树脂可允许通过的最大三乙醇胺浓度不应超过250mg/L;树脂中机油含量大于1%时,树脂的工作交换容量下降16%;树脂中机油含量大于11%时,树脂几乎完全失效。 相似文献
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Dah-Yu Kao Liang-Cheng Chen Tung-Jen Wen Charles-Fang Chu 《Journal of Nuclear Science and Technology》2016,53(6):921-927
The amount of total organic carbon (TOC) leached from cation exchange resins (CERs) in condensate demineralizers are related to the quality of reactor water in nuclear power plants (NPPs). In the recent years, quality problems of CERs used by ChinShan and KuoSheng NPPs have been identified. Prior to use, TOC and sulfate concentrations must be reduced to meet the criteria; however, this involves an extended purification process and heavy use of water resources. Even in cases where resin can be used, the quality of the water in the reactor remains poor. This study, therefore, investigated the leachates of resins from these NPPs in order to establish a reference for the quality of deep bed CERs. Gel permeation chromatography and ion-pair chromatography were used to identify molecular peaks in the CER leachates in order to elucidate the molecular distributions. We also sought to determine TOC and sulfate concentrations of post-UV treatment using long-term soaking tests, in which the solutions used to soak resins were drained off for analysis on a daily basis. Hydrogen peroxide is employed to accelerate the aging process associated with decomposition in soaking tests to determine the stabilities of the resins. 相似文献
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常规核级离子交换树脂锂型转型率的测量采用将离子交换树脂中的锂用酸淋洗后测量锂浓度,再计算锂型转型率,存在分析时间长、分析结果偏低等不足。本文采用微波消解-原子吸收法测量核级离子交换树脂的锂型转型率,利用微波消解实现树脂的完全消解,利用原子吸收仪测量锂浓度,结合氢型树脂湿基工作交换容量计算离子交换树脂的锂型转型率,实现离子交换树脂锂型转型率的准确测量。分析结果表明,锂浓度加标回收率为99%,相对标准偏差为0.97%(n=7),锂型转型率达99.20%。方法具有离子交换树脂使用量少、分析结果准确等优点,可用于核级离子交换树脂锂型转型率的测量。 相似文献
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采用中子活化技术测定了沉积有机质中的无机组分-痕量元素,并以此作为划分有机质类型的依据,以松辽盆地北部深层高成熟度有机质为例进行了探索,结果表明沉积有机质中V,Ni等元素的丰度与有机质母质类型的关系密切,特别是当有机质的演化程度很高时,这些元素的丰度仍有十分显著的差异,这就工分高成熟度沉积有机质类型提供了一种新的方法。 相似文献
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通过热重实验以及台架试验,进行了废阴/阳离子交换树脂的高温裂解处理技术研究。结果表明,通过电磁感应加热反应器中的金属球并辅助搅拌,可以实现树脂的高温裂解。相比于氮气和水蒸气,空气是更合适的反应气氛。在空气氛围下,当树脂处理量为1 kg/h时,设定空气流量2 m3/h,反应温度600 ℃~700 ℃,添加剂选择CuSO4·5H2O,阴/阳离子交换树脂经本裂解工艺处理,废物残留率分别为8%和12%左右,两种树脂最终的裂解残留率可以达到3%~5%左右,可以实现较为彻底的裂解反应。阴离子和阳离子交换树脂的裂解反应有明显的区别,其中阴离子交换树脂热敏性更高,裂解需要的温度和空气流量更低,但反应更剧烈,烟气量更大。 相似文献
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十红滩铀矿床属层间氧化带砂岩型铀矿床,赋存于中侏罗统西山窑组含煤碎屑岩中。容矿层岩石中富含有机质,有机碳、可溶有机物、酸解吸附烃在不同地球化学分带的岩石中含量大小不同,尤以氧化还原过渡带含量最高。矿石有机质母质类型为腐殖型,处于未成熟演化阶段,酸解吸附烃为煤成气型。统计计算表明:容矿层中铀和可溶有机物、酸解吸附烃含量之间具明显的相关关系。分析了有机质在砂岩型铀矿床形成过程中的作用,认为容矿层中有机质在含氧环境下分解的产物利于铀在水中的溶解和迁移,而在缺氧条件下分解的产物,构成铀沉淀的还原和吸附地球化学障,在铀的成矿过程中发挥重要的作用。 相似文献
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测定了西安脉冲堆净化系统混床废阴、阳离子交换树脂的理化性能参数,分析了废阴、阳离子交换树脂发生的性能变化,并考察了不同影响因素对树脂性能变化的贡献。根据废树脂中的杂质分布情况,分析了西安脉冲堆一回路水受到的外来污染情况、反应堆结构材料的腐蚀情况。分析结果显示,混床废阴树脂已基本丧失交换能力,而废阳树脂的剩余交换能力仍较高。反应堆运行产生的辐射效应引起的树脂性能变化较小。废阴树脂交换能力的丧失归因于其交换了大量的杂质离子碳酸根和一定量的有机物。废阴树脂中其它阴离子含量很低,废阳树脂中杂质金属元素含量也很低,说明西安脉冲反应堆堆池水并未受到明显的外来污染。反应堆水池内结构材料存在一定的腐蚀。所得结果为此类反应堆净化系统的安全运行提供了重要的参考数据。 相似文献
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Toru Kitagaki Toshitaka Kaneshiki Masao Nomura Tatsuya Suzuki 《Journal of Nuclear Science and Technology》2016,53(10):1639-1646
Ion exchange is one of the most useful separation methods. Certain ion exchange resins have been developed for use in reprocessing technology. The purpose of this study is to evaluate the U selectivity of a benzimidazole-type anion exchange resin and its potential for the separation of U from a solution of simulant fuel debris in HCl. The selectivity of the benzimidazole-type anion exchange resin for adsorption of the major elements present in fuel debris in HCl solution (such as in debris from the Fukushima Daiichi nuclear power plant) was analyzed, and the tendencies were discussed from the viewpoint of complexation. Moreover, chromatographic separation of U from the other elements was evaluated using the resin. The results indicate that this type of resin has high U separation selectivity. Consequently, the authors developed a novel strategy involving the use of this resin for U separation in conjunction with chlorination of hardly soluble materials by using atmospheric-pressure nonthermal plasma. This strategy is also proposed to be applicable for stabilizing waste forms and for nuclear fuel material accounting, such as for debris from the Fukushima nuclear power plant and other complex hardly soluble nuclear materials. 相似文献
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《Journal of Nuclear Science and Technology》2013,50(1):123-129
Ion-exchange resins doped with toxic metals and radioactive metal surrogates were test-burned in a bench-scale molten salt oxidation (MSO) reactor system. The purposes of this study are to confirm the destruction performance of the two-stage MSO reactor system for the organic ion-exchange resin and to obtain an understanding of the behavior of the fixed toxic metals and the sulfur in the cationic exchange resins. The destruction of the organics is very efficient in the primary reactor. The primarily destroyed products such as carbon monoxide are completely oxidized in the secondary MSO reactor. The overall collection of the sulfur and metals in the two-stage MSO reactor system appeared to be very efficient. Over 99.5% of all the fixed toxic metals (lead and cadmium) and radioactive metal surrogates (cesium, cobalt, strontium) remained in the MSO reactor bottom. Thermodynamic equilibrium calculations and the XRD patterns of the spent salt samples revealed that the collected metals existed in the form of each of their carbonates or oxides, which are non-volatile species at the MSO system operating conditions. 相似文献
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《Journal of Nuclear Science and Technology》2013,50(12):746-752
Several forms of cation exchange resins with different crosslinkages have bsen subjected to 60Co γ-radiation, in wet or dry state and the effects of such variables as adsorbed ionic species, crosslinkage of the resin, and the water content in the resin on radiation damage to organic resin have been examined in their relation to γ-radiation dose. The result showed that radiation caused marked changes in the chemical and physical properties of the resin, and phenomena such as de-crosslinking, loss of strong-acid capacity, formation of a functional group composed of a weak-acid exchange group were observed. The degree of such degradation phenomena was not affected by adsorbed ions when their valency states were kept unchanged during irradiation, but when the adsorbed ions were reduced during exposure, the extent of degradation was found inhibited to a significant extent. It may be concluded from the results that the decomposition of the cation exchange resin is mainly initiated by reaction with the resin produced by radiation-formed reducing species, i.e., H atoms. A mechanism of resin degradation is also proposed. 相似文献