Fixed bed reactor for catalytic reduction of hexavalent uranium by hydrazine nitrate, and application thereof

Abstract

The invention discloses a novel multi-section adiabatic fixed bed reactor device for producing tetravalent uranium through catalytic reduction of hexavalent uranium by hydrazine nitrate. The main function of the device is to control the reaction liquid residence time distribution, the reaction temperature and the acidity in a reaction process in the form of a multi-section adiabatic fixed bed reactor so as to enable the reaction liquid to be in the optimal operation interval, so that minimization of solid high-level radioactive waste discharge is achieved, and the purposes that the content oftetravalent uranium at an outlet meets the requirement and a catalyst is prevented from being oxidized and inactivated due to excessive consumption of hydrazine nitrate. In the optimal implementationscheme, the conversion rate of hexavalent uranium at the outlet of the reactor is greater than 98%, the conversion rate of hydrazine nitrate is lower than 35%, and the content of tetravalent uranium at the outlet of the reactor is greater than 200 g / L.

Description

technical field

[0001] The invention relates to a multi-stage adiabatic fixed-bed reactor for reducing hexavalent uranium to generate tetravalent uranium, in particular to a reactor that can be used to reduce hexavalent uranium to generate tetravalent uranium by using hydrazine nitrate as a reducing agent device. Background technique:

[0002] With the large-scale development and application of nuclear power, the clean treatment and efficient recycling of nuclear spent fuel have become the key to the further development of nuclear power. At present, the technology mainly adopted by domestic and foreign reprocessing plants is the Purex process. In the process of this process, the valuable uranium and plutonium elements are first extracted into the organic phase through the extraction unit, so as to be separated from most of the splinter elements to achieve the purpose of decontamination; The valence plutonium is reduced to trivalent and enters the water phase, but the hexav...

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