Method for extracting uranium by using ion exchange fixed tower under alternate Ph condition

Abstract

The invention relates to a method for extracting uranium by using an ion exchange fixed tower, in particular to a method for extracting uranium by using an ion exchange fixed tower under the alternate Ph condition. The method comprises the steps of absorbing uranium by barren resin and eluting the uranium-carried resin to obtain uranium, wherein the step of eluting the uranium-carried resin to obtain uranium also comprises the following stages of elution neutralization, qualified liquid elution, first barren elution and second barren elution. In the stage of elution neutralization, an alkali eluent is used to neutralize residual acid in the uranium-carried resin, and the feeding mode is lower liquid feeding; in the stage of qualified liquid elution, the feeding mode is upper liquid feeding; in the stage of first barren elution, the feeding mode is upper liquid feeding, and the effluent liquid is a first barren solution; and in the stage of second barren elution, the feeding mode is upper liquid feeding, and the effluent liquid is a second barren solution. The invention increases elution efficiency and shortens elution volume by dividing the step of eluting the uranium-carried resin to obtain uranium into the stages of elution neutralization and qualified liquid elution and by respectively using the upper liquid feeding mode and the lower liquid feeding mode.

Description

technical field [0001] The invention belongs to a method for extracting uranium using an ion-exchange fixed tower, in particular to a method for extracting uranium by an ion-exchange fixed tower under the condition of alternating pH of the solution. Background technique [0002] The ion exchange method is used to extract uranium from the leach solution. For areas without special environmental protection requirements, the ion exchange method generally selects the type of eluent according to the characteristics of the ore leach solution. Washing agent, neutral or weak alkaline eluting agent is used to recover and extract uranium from neutral or weak alkaline solution. At present, most uranium water smelters in my country adopt acid leaching—anion exchange resin adsorption—acid chloride or acid nitrate leaching—precipitation process. Among them, the operation of the ion exchange tower adopts a single upper or lower feeding method. When the uranium concentration of the leaching...

AI Technical Summary

Problems solved by technology

[0003] Acid leaching—anion exchange resin adsorption—acid chloride salt or acid nitrate leaching—precipitation product process flow, since the uranium-loaded resin uses acid chloride salt or acid nitrate for desorption, in the process water cycle process It will lead to the continuous accumulation of chloride or nitrate, which will affect the subsequent adsorption of ion exchange resin, and the adsorption tail liquid needs to be discharged

For areas with strict environmental protection requirements or no receiving water bodies, this uranium extraction process cannot meet the relevant national environmental protection requirements

[0004] If carbonate is used to wash the ion exchange resin used to extract uranium from the acidic leaching solution, the closed circuit circulation of process water can be realized, but in the initial stage of washing, the acid-base neutralization reaction will produce a large amount of CO 2 Bubbles, if not handled properly during the actual operation, will cause damage to pipelines and equipment, and bring great safety hazards to production

Images