The Effect Of Hydrazine Addition On The Formation Of Oxygen Molecule By Fast Neutron Radiolysis
Abstract
Hypothetically speaking, hydrazine could suppress the oxygen formation as a major of corrosion initiator. In this work, we developed a calculation model to understand the effect of hydrazine addition toward the oxygen under PWR condition. Our great interest is to study whether this strategy would also be effectively applied in PWRs[P1] . In the present work, the effect of hydrazine on suppressing the molecule oxygen under neutron irradiation is described. The simulation was done by using FACSIMILE. The variation dose applied assuming a batch system and at high dose ~104 Gy s-1. Three different temperatures were applied, which are room temperature, 250 and 300 oC at two system oxygenated water, which are aeration and deaeration. At room temperature, for deaerated condition, added hydrazine under a range of 10-6 – 10-4 M into primary coolant were not effective to suppress O2 form since the effect was similar as in the pure water system since for 10-3 M hydrazine addition, a large produce of O2 were obtained. In reverse, for deaerated condition, hydrazine concentrate about 10-3 M can suppress O2 form significantly, while hydrazine add in the range between 10-6 – 10-4 M is again confirmed to be the same as in pure water system. For high temperature, at 250 and 300 oC, the results showed that in deaerated condition, hydrazine addition can suppress O2 form proportionally to its concentration while in aerated condition, hydrazine add with concentration of 10-6 and 10-5 M were not effectively to suppress O2 form, a slightly decrease of O2 occurred due to the addition of 10-4 M hydrazine and 10-3 M of hydrazine can suppress the formation of O2 significantly. [P2]
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