A3-3基体石墨的氧化行为

周湘文; 卢振明; 李馨楠; 张杰; 刘兵; 唐亚平

doi:10.1016/S1872-5805(16)60010-0

A3-3基体石墨的氧化行为

doi: 10.1016/S1872-5805(16)60010-0

清华大学核能与新能源技术研究院, 先进核能技术协同创新中心, 先进反应堆工程与安全教育部重点实验室, 北京 100084

基金项目: 国家公派留学基金(201406215002);国家科技重大专项(ZX06901);清华大学自主科研项目(20121088038).

详细信息

通讯作者:
周湘文,博士,副研究员.E-mail:xiangwen@tsinghua.edu.cn

中图分类号: TQ165
计量
- 文章访问数: 552
- HTML全文浏览量: 85
- PDF下载量: 563
- 被引次数: 0
出版历程
- 收稿日期: 2016-02-26
- 录用日期: 2016-04-21
- 修回日期: 2016-04-02
- 刊出日期: 2016-04-28

The oxidation behavior of A3-3 matrix graphite

Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the key laboratory of advanced reactor engineering and safety, Ministry of Education, Beijing 100084, China

Funds: State Scholarship Foundation of China(201406215002); Chinese National S & T Major Project(ZX06901); Tsinghua University Initiative Scientific Research Program(20121088038).

摘要

摘要: 采用自行搭建的热重实验平台对798~973 K温度范围内温度对A3-3基体石墨的氧化行为进行研究,氧化剂为100 mL/min的空气。不同温度下石墨试样均被氧化至失重10%~15%。结果表明,基体石墨的氧化速率(OR)随着温度的升高显著提升,温度为973 K时基体石墨的OR约为798 K时的70倍。虽然973 K时氧气供给速率与平均碳消耗速率的比值仅为4.3,但石墨OR的Arrhenius曲线依然保持了很好的线性关系,表明该温度下基体石墨的氧化机理没有发生改变。在798-973 K温度范围内,A3-3基体石墨在空气中的氧化均处于化学区,其活化能为176 kJ/mol,Arrhenius氧化方程可描述为:OR=2.9673×10⁸·exp(-21124.8/T),单位为wt%/min。与堆内的核级结构石墨相比,基体石墨的活化能相对较低,说明基体石墨在空气中更易被氧化,这主要跟基体石墨中含有未完全石墨化的树脂炭有关。
- 氧化行为 /
- 基体石墨 /
- 化学控制区 /
- 活化能
Abstract: The effects of temperature on the oxidation behavior of the A3-3 matrix graphite(MG) in the temperature range 798-973 K in air with a flow rate of 100 mL/min to burn-offs of 10-15 wt%, were investigated by a home-made thermo-gravimetric experimental setup. The oxidation rate(OR) increases significantly with the temperature. The OR at 973 K is over 70 times faster than at 798 K. The oxidation kinetics of A3-3 MG in air at temperatures up to 973 K is in the reaction control regime, where the activation energy is 176 kJ/mol and the Arrhenius equation could be described as:OR=2.9673×108·exp(21124.8/T) wt%/min. The relatively lower activation energy of MG than that of structural nuclear graphite indicates that MG is more easily oxidized.
- Oxidation behavior /
- Matrix graphite /
- Chemical control regime /
- Activation energy

HTML全文

参考文献(18)

ZHOU Xiang-wen, YI Zi-long, LU Zhen-ming, et al. Graphite materials in pebble-bed high temperature gas-cooled reactors[J]. Carbon Techniques, 2012, 6:B9-B13.

Moormann R, Hinssen H-K, Kuhn K. Oxidation behavior of an HTR fuel element matrix graphite in oxygen compared to a standard nuclear graphite[J]. Nuclear Engineering and Design, 2004, 227:281-284.

Zhou Xiangwen, Lu Zhenming, Zhang Jie, et al. Preparation of spherical fuel elements for HTR-PM in INET[J]. Nuclear Engineering and Design, 2013, 263:456-461.

Hrovat M, Grosse K H. Manufacture of high corrosion resistant fuel spheres(FS) for high temperature pebble bed modular reactors(PBMR)[C]. Proceedings of the HTR2006, B00000281, Johannesburg, South Africa, 2006.

Xueliang Qiu, Shichao Zhang, Jun He, et al. Oxidation behavior of the matrix materials. IAEA-TECDOC-901:graphite moderate lifecycle behavior[C]. Specialist Meeting on the Graphite Moderator Lifecycle Behavior, Bath, United Kingdom, 1996:351-362.

Fuller E L, Okoh J M. Kinetics and mechanisms of the reaction of air with nuclear grade graphites:IG-11. Journal of Nuclear Materials, 1997, 240:241-250.

Kim E S, Lee W W, No H C. Analysis of geometrical effects on graphite oxidation through measurement of internal surface area[J]. Journal of Nuclear Materials, 2006, 348:174-180.

Choi W K, Kim B J, Kim E S, et al. Oxidation Behavior of IG and NBG nuclear graphites[J]. Nuclear Engineering and Design, 2011, 241:82-87.

Contescu C I, Azad S, Miller D, et al. Practical aspects for characterizing air oxidation of graphite[J]. Journal of Nuclear Materials, 2008, 381:15-24.

Lee J J, Ghosh T K, Loyalka S K. Oxidation rate of nuclear-grade graphite NBG-18 in the kinetic regime for VHTR air ingress accident scenarios[J]. Journal of Nuclear Materials, 2013, 438:77-87.

Clark T J, Woodley R E, deHalas D R. Gas-graphite systems[C]. R. E. Nightingale(Ed.), Nuclear Graphite, Academic Press, New York, 1962:387.

Moormann R, Hinssen H K, Krussenberg A K, et al. Investigation of oxidation resistance of carbon based first-wall liner materials of fusion reactors[J]. Journal of Nuclear Materials, 1994, 212-215:1178-1182.

Pappano P J, Burchell T D, Hunn J D, et al. A novel approach to fabricating fuel compacts for the next generation nuclear plant(NGNP)[J]. Journal of Nuclear Materials, 2008, 381:25-38.

Hinssen H K, Katcher W, Moormann R. Kinetics Der Graphite/sauerstoff Reaction[M]. Juel-1875, 1983.

Blanchard A. Appendix 2. The thermal oxidation of graphite, irradiation damage in graphite due to fast neutrons in fission and fusion systems[R]. IAEA-TECDOC-1154, 2003:207-213.

Standard test method for air oxidation of carbon and graphite in the kinetic regime[S]. An American National Standard, D7542-09, 2009.

Zaghib K, Song X, Kinoshita K. Thermal analysis of the oxidation of natural graphite:isothermal kinetic studies[J]. Thermochim. Acta, 2001, 371:57-64.

Hawtin P, Gibson J A, Murdoch R, et al. The effect of diffusion and bulk gas flow on the thermal oxidation of nuclear graphite-I. Temperatures below 500℃[J]. Carbon, 1964, 2:299-309.

施引文献

资源附件(0)

访问统计