Medical isotope production reactor capable of reducing reactor core uranium inventory

Abstract

The invention discloses a medical isotope production reactor capable of reducing reactor core uranium inventory. A fuel solution of the medical isotope production reactor is a water solution formed by mixing 24 to 34gU / L of uranium nitrate in concentration with 50 to 70% of heavy water and 30 to 50% of light water in volume. A reactor core reflecting layer is made of graphite. A reactor core is not provided with a control rod guide tube. A reactor core cooling tube in a reactor container is centralized outwards and annularly arranged between 0cm and 15cm of the inner wall of the reactor container approximately. The medical isotope production reactor reduces the uranium inventory and solves the problem of negative reactivity caused by water-adding dilution or evaporation-caused dehydration concentration of the reactor core.

Description

technical field [0001] The invention relates to a nuclear reactor, in particular to core optimization of a medical isotope production reactor. Background technique [0002] The medical isotope production reactor is a solution type nuclear reactor. At present, the reactor power of the solution reactor in operation in the world is 20-50 kW, the highest power is 50kW, and the volume of the reactor solution is small (<20L). Both evaporation and dehydration concentration introduce negative reactivity. When the external power supply is cut off and the control rod refuses to move, the temperature of the solution is increased to introduce negative reactivity, so that the power of the stack drops and the power of natural heat dissipation is balanced, and the fuel solution does not boil at this time. [0003] At present, the fuel solution used in medical isotope production reactors is a mixed aqueous solution of uranyl nitrate and light water. The disadvantage of this fuel soluti...

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Problems solved by technology

[0003]Currently, the fuel solution used in medical isotope production reactors is a mixed aqueous solution of uranyl nitrate + light water. The moderation capability is very strong, and the required backup reactivity has been achieved if the core is small. If the power is high, the core cannot run stably. If the core is enlarged, the uranium loading needs to be increased. Increase the absorber to suppress the backup reactivity; if it is changed to uranyl nitrate + heavy water, since the ability of heavy water to moderate neutrons is worse than that of light water, it is necessary to install a large amount of heavy water, resulting in too large a core volume. When the concentration is low, the adsorption capacity is poor, so the isotope yield is low

A 200kW reactor requires a solution volume of about 100L. When there are a large number of cooling tubes and control rod conduits, the volume of the reactor solution can approach or reach 100L, which makes the reactor solution contain a large amount of uranium (3.6~4.0 kg), which is very uneconomical.

[0006] At present, there is no solution reactor operating above 200 kW in the world. Therefore, it is necessary to provide a solution that can reduce the amount of U-235 and meet the volume requirements of the reactor. , and it is necessary to introduce a negative reactive medical isotope production reactor when the reactor solution enters or loses water

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