Radioactive organic extractant waste liquid treatment method and device

Abstract

The invention discloses a radioactive organic extractant waste liquid treatment method, which comprises: carrying out rectification treatment on a radioactive organic extractant waste liquid, separating nuclide and a heavy radiolysis product to obtain a first mixture and TBP, and separating a light radiolysis product in the first mixture to obtain kerosene. The invention further discloses a radioactive organic extractant waste liquid treatment system which comprises a first-stage rectification unit and a second-stage rectification unit; the first-stage rectification unit is used for separating nuclides and heavy radiolysis products in radioactive organic extractant waste liquid, and a first mixture and TBP are obtained; and the second-stage rectification unit is connected with the first-stage rectification unit and is used for separating light radiolysis products in the first mixture to obtain kerosene. According to the method, TBP and kerosene in the radioactive organic extractant waste liquid can be recycled, the volume of the radioactive organic extractant waste liquid is effectively reduced, the final disposal amount of the radioactive organic extractant waste liquid is greatly reduced, and cost is saved.

Description

technical field [0001] The invention belongs to the field of nuclear technology, and in particular relates to a method and a device for treating radioactive organic extractant waste liquid. Background technique [0002] Since tributyl phosphate (TBP) has a significant difference in the extraction of uranium, plutonium and fission products, and kerosene (OK) can be used as a diluent to reduce the density and viscosity of the system, the nuclear fuel reprocessing industrial Purex process (Purex Nuclear fuel reprocessing process) often choose 30% TBP / OK as the extraction agent. During the extraction process, under the action of radiolysis and hydrolysis in acidic environment, 30% TBP / OK extractant will degrade and generate various degradation products, which will deteriorate the performance of the extractant and bring harm to the extraction process, resulting in The decontamination coefficient decreases, the retention of uranium and plutonium in the waste liquid increases, and...

AI Technical Summary

Problems solved by technology

Although the alkaline washing regeneration method has a good effect on removing DBP, MBP and other acidic radiolysis products, because the heavy radiolysis products are mainly a series of long-chain acidic phosphate esters and acidic radiolysis products composed of alkyl groups and TBP Dipolyphosphate tributyl phosphate, long-chain alkyl neutral phosphate, this kind of substance has obvious polarity, strong interface activation, and remarkable retention of metal products, and due to the long chain of the alkyl group, the The solubility is very large, it cannot be removed in alkaline washing, and it will gradually accumulate in the organic phase, resulting in poor effect of the alkaline washing regeneration method on neutral radiolysis products and heavy radiolysis products. Therefore, extraction at 30% TBP / OK After the agent is used for a period of time, it needs to be updated, which will not only increase the operating cost, but also produce a large amount of radioactive organic extractant waste liquid, and, because the vast majority of these radioactive organic extractant waste liquids are TBP and kerosene, radionuclide Radiation and radiolysis products only account for a small part. If they are disposed directly, not only the disposal volume will be large, but the disposal cost will be high, and it will also cause waste of resources.

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