Na冷却高速炉におけるNa中での水素の存在形態に着目した挙動推定 [Published online J. Comput. Chem. Jpn., 21, 61-62, by J-STAGE]

[Published online Journal of Computer Chemistry, Japan Vol.21, 61-62, by J-STAGE]
<Title:> Na冷却高速炉におけるNa中での水素の存在形態に着目した挙動推定
<Author(s):> 畠山 望, 三浦 隆治, 宮本 直人, 宮本 明, 荒 邦章, 下山 一仁, 加藤 篤志, 山本 智彦
<Corresponding author E-Mill:> hatakeyama(at)aki.niche.tohoku.ac.jp
<Abstract:> In the cooling system of sodium-cooled fast reactors, it is required to identify and rapidly detect hydrogen explosively produced by the sodium-water reaction when a water leak occurs due to damage of a heat exchanger tube in a steam generator (SG), in contrast to low-concentration background hydrogen permeating through SG tubes during normal operation. In the present study, we focus on the difference between the background hydrogen and the hydrogen generated by the sodium-water reaction, and theoretically estimate the hydrogen behavior in liquid sodium by using computational chemistry methods. We find that dissolved H or NaH, rather than H2, is the predominant form of the background hydrogen in liquid sodium, and that hydrogen produced in large amounts by the sodium-water reaction can exist stably as fine bubbles with a NaH layer on their surface.
<Keywords:> Sodium-cooled fast reactor (SFR), Steam generator (SG), Sodium-water reaction, Hydrogen detection, Ultra-accelerated quantum chemical molecular dynamics (UA-QCMD)
<URL:> https://www.jstage.jst.go.jp/article/jccj/21/2/21_2022-0026/_article/-char/ja/