Design and Stress Analysis of Extraterrestrial ... - The Black Vault

I
SFig. 2.74. Structural.diagpam of
a regenerative fuel element.
LiF--
Liquid-metal fuel element (mercury-mercury amalgam)
Sodium amalgam and mercury enter into an electrochemical.
reaction in the fuel element; (5, Fig. 2.75). The reaction products
are then thermally divided into the initial reagents by means ?f
distillation in the regenerator 2; heat for separation is obtained'
from heat source 1.
The basis of the fuel element consists of a porous ceramic
ion membrane saturated by an electrolyte of liquefiec sodium liaat.
The melt is held in the pores of the membrane by capillary forces.?,
When the sodium flows through the element, its atoms are transformed
into ions on the surface of the membrane, giving a negative c1arge
to the electrode. .
Simultaneously the sodium ions are transformed into atomA on
the surface of the second electrode where the.y react with the merc'ury,
forming an intermetallic compound of the Naxltg type. As a res.ult
of the overflow of sodium ions, the sodium concentration near the
negatively charged surface of the membrane decreases; near the
positively charged surface the mercury is saturated by a weak
solution of sodium.
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