Method for recovering phosphorus from phosphorite tailings and preparing light magnesium oxide

Abstract

The invention relates to a method for recovering phosphorus from phosphorite tailings and preparing light magnesium oxide. The method comprises the following steps of: calcining the phosphorite tailings; digesting calcined products to obtain digestion slurry and digestion products; separating the digestion products by using a table concentrator to obtain concentrates, middlings and tailings, wherein the concentrates are phosphorus concentrates and the middlings and the tailings are magnesium-enriched products; performing acid leaching on the magnesium-enriched products to obtain magnesium-enriched leachate and leaching slag; mixing the magnesium-enriched leachate and the digestion slurry, removing impurities, and carbonizing to prepare the light magnesium oxide; and recovering rich phosphorus pentoxide in the phosphorus concentrates and the leaching slag. By the method, phosphorus-containing ores in the phosphorite tailings are recovered effectively, and the light magnesium oxide is prepared, so that the aim of comprehensively utilizing the phosphorite tailings is fulfilled; and the total recovery rate of the phosphorus pentoxide is 98.88 percent, the content of magnesium oxide in the light magnesium oxide prepared by treating the leachate and the digestion slurry is 93.09 percent, and the quality of the light magnesium oxide meets the requirements for qualified products in the standard HG / T2573-94.

Description

technical field [0001] The invention relates to the technical field of comprehensive recovery of phosphate rock tailings, in particular to a method for recovering phosphorus from phosphate rock tailings and preparing light magnesium oxide. Background technique [0002] P in phosphate rock tailings 2 o 5 The content is about 8.52%, and the MgO content is about 16%. The main mineral is dolomite, followed by fluoroapatite, quartz and illite. Based on the annual production of 500,000 tons of tailings, there will be 46,900 tons of P 2 o 5 And 88,600 tons of MgO are piled up with the tailings but not utilized. The stockpiling of tailings not only occupies a large amount of land, but also the relevant components in the tailings sand and the residual beneficiation agents will cause serious harm to the ecological environment. With the gradual reduction of high-grade phosphate rock resources, the comprehensive development of phosphorus resources in phosphate rock tailings is extr...

AI Technical Summary

Problems solved by technology

The re-election of phosphate rock tailings is mainly flotation, but the development of high-efficiency collectors and inhibitors used in flotation is difficult, and the agents have a greater impact on the environment

Although the development of building materials products has made use of phosphate rock tailings, but the added value is low and the resources have not been rationally utilized

For the processing and utilization of associated minerals, the acid leaching method is commonly used to treat phosphate rock tailings, but the acid consumption is large, and the extraction and removal of impurities are difficult