Safe nuclear waste transmutation target and preparation method thereof

Abstract

The invention provides a safe nuclear waste transmutation target. The target is prepared by the following steps: filling nuclear waste powder with the average grain diameter of between 0.1 and 10mm in a percolation mould (6), and preheating for 1 to 300 minutes at the temperature of between 100 and 600 DEG C after ramming, tamping or compacting seal treatment; pouring molten aluminum or a molten aluminum alloy, sealing and fixing a seal cap (4); and introducing a gas with the pressure of between 0.1 and 1MPa into the mould (6), cooling and solidifying, and demoulding to obtain a composite material blank containing aluminum or an aluminum alloy (2) and nuclear waste powder (3), manufacturing the blank into a core material, and encapsulating the core material in an aluminum jacket (1) to obtain the transmutation target. In the safe nuclear waste transmutation target, high heat generated inside the core material during transmutation is quickly conducted to the aluminum jacket and finally dissipated by a radiation or convection mode by utilizing the excellent heat conductive performance of the aluminum or the aluminum alloy, so that the environmental problem caused by core material cracking or aluminum jacket bursting at a high temperature is avoided.

Description

1. Technical field [0001] The present invention relates to nuclear waste target materials in nuclear waste treatment engineering, in particular to transmutation targets for shortening the half-life of nuclear waste through neutron-induced transmutation. Specifically, the nuclear waste is encapsulated on an aluminum matrix by using the high-pressure seepage method of molten aluminum A safe nuclear waste transmutation target and a preparation method thereof. 2. Background technology [0002] There are tens of thousands of tons of nuclear waste in the world, from nuclear reactors, other nuclear processes and obsolete nuclear weapons systems. There is currently no proper way to dispose of them, usually by deep geological burial. We know that some nuclear wastes have a very long life span of millions of years, such as 129 The half-life of I is 1.57×10 7 year. Safely storing this nuclear waste underground for millions of years is a big problem. The transmutation technology of...

AI Technical Summary

Problems solved by technology

At present, there are two main ways to prepare transmutation targets. One is to directly press the nuclear waste into blocks. In this form, the targets are very easy to absorb moisture, which will cause the target to collapse and pollute the transmutation equipment.

The other is to directly encapsulate it in the aluminum cladding, which has poor thermal conductivity, and it is difficult to conduct the high temperature generated by the radiation in the core of the nuclear waste, which will cause the transmutation target to burst or the cladding to burst.

In addition, the water chemical properties of the above two forms of transmutation targets are not ideal, and they are very easy to react with water at high temperature. In this way, in the event of an accident, nuclear waste may be dissolved into the circulating water, causing environmental pollution.

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