A kind of preparation method of rare earth carbonate that does not produce ammonia nitrogen wastewater

Abstract

The invention discloses a preparation method of rare earth carbonate free of generation of ammonia-nitrogen wastewater, and belongs to the technical field of production of rare earth carbonate. The method comprises the following steps: deacidifying by a rare-earth solution; precipitating rare earth by using ammonium bicarbonate; collecting carbon dioxide bubbles generated during rare earth participation; carrying out chemical reaction on carbon dioxide and calcium peroxide to release oxygen and water; participating rare earth by using ammonium bicarbonate again; dewatering and washing a rate block which is crystallized when the pH value is greater than 7 until the rare earth carbonate is obtained; and carrying out environmental-friendly and energy-saving treatment on the left ammonia-nitrogen wastewater, thereby achieving pollution-free production when the deamination rate and the denitrification rate reach 99.9%. The preparation method has the advantages of fully utilizing the ammonium bicarbonate to participate the rate earth, and effectively processing non-environmental-friendly processes in the production process, and therefore, cyclic utilization of resources and environmental-friendly production are achieved.

Description

technical field [0001] The invention relates to the technical field of rare earth carbonate production, in particular to a method for preparing rare earth carbonate that does not generate ammonia nitrogen wastewater. Background technique [0002] Rare earths are known as "industrial vitamins". They have excellent optical, electrical, magnetic, superconducting, catalytic and other physical properties, and can be combined with other materials to form new materials with different properties and varieties. It is an indispensable core resource for strategic industries such as new energy and new materials. Among them, rare earth in the form of rare earth carbonate is an indispensable raw material in many industries. At present, there are more and more processes for making rare earth carbonates, but usually the processes for making rare earth carbonates will produce high-concentration ammonia nitrogen wastewater. Now domestic wastewater discharge standards are becoming more and m...

AI Technical Summary

Problems solved by technology

Although the continuous chemical precipitation method has smaller investment and floor space than the A / O method, its consumption of chemicals is too large, the ratio of N:P:Mg is 1:1.1-1.2, the cost of treating chemicals is too high, and It is impossible for the effluent to meet the national primary or secondary discharge standards

In the prior art, not only the ammonia nitrogen wastewater cannot be effectively treated, but also there are still many problems in the production process of rare earth carbonic acid

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