Method of leaching vanadium from roasted stone coal

Abstract

The invention relates to a method of leaching vanadium from roasted stone coal. According to the technical scheme, roasted stone coal is finely ground and is mixed well with water to obtain mixed pulp; concentrated sulfuric acid is added into the mixed pulp and leached under vapor and stirring conditions to obtain acid leaching slurry; the acid leaching slurry is subjected to three-stage leaching: stage I leaching refers to adding calcium fluoride into a first single-stage stirring leaching tank of a stage I leaching apparatus for leaching, stage II leaching refers to 1-2 hours of leaching prior to adding adjusted slag into a last single-stage stirring leaching tank of a stage II leaching apparatus for continued leaching, and stage III leaching refers to adding an aluminum remover into a first single-stage stirring leaching tank of a stage III leaching apparatus for leaching, and final acid leaching slurry is obtained; solid-liquid separation is carried out to obtain final acid leaching liquid and leaching residue; pH of the final acid leaching liquid is adjusted, and solid-liquid separation is carried out to obtain adjusted acid leaching liquid and adjusted residue. The method has low production cost, is easy to industrialize and has the advantages of high vanadium leaching rate and low content of impurity ions in leachate.

Description

technical field [0001] The invention belongs to the technical field of vanadium-containing stone coal. Specifically relates to a method for leaching vanadium from stone coal roasting material. Background technique [0002] Stone coal is an important vanadium-containing resource in my country. It is rich in reserves in China. It has high carbon and hydrogen content, has a certain calorific value, and has high hardness and is difficult to grind. In addition to the high silicon content in stone coal, the aluminum content is also high. The current conventional process for extracting vanadium from stone coal is roasting-leaching-purification and enrichment-vanadium precipitation-calcination. The leaching process of stone coal roasting materials is mainly based on acid leaching. The selectivity of acid leaching to metals is poor, and the leaching of vanadium and aluminum has a high correlation. High, and the pH value of the obtained pickling solution is low, the sulfuric acid i...

AI Technical Summary

Problems solved by technology

This leaching process combines leaching and ion exchange into one step, which shortens the process, but requires high equipment, and the resin in the pulp method has a large loss of resin, and is not conducive to the realization of industrialization

[0005] "A Stone Coal Vanadium Ore Leaching Process for Recovery and Utilization of Residual Acid" (CN104988337A) patented technology, this technology adopts the process of high acid leaching-solid-liquid separation-vanadic acid separation-acid water return leaching, this method removes the vanadium in the leachate Acid separation, recovery of residual sulfuric acid, improves the utilization rate of acid, but the separation process of vanadic acid is relatively complicated and the separation efficiency is not high, resulting in increased process flow, increased production costs, and high content of impurity ions in the leachate

[0006] "A Two-Stage Slaking Vanadium Extraction Method for Stone Coal Vanadium Ore" (CN104451201A) patent technology, this technology adopts the process of high temperature slaking-water immersion-low temperature slaking-water leaching, which can improve the utilization rate of acid, but slaking vanadium extraction is harmful The equipment has high requirements for corrosion resistance and high temperature resistance. The two-stage solid-liquid separation and two-stage water immersion lead to a long process, high production costs, and high impurity content in the resulting leachate

[0007] To sum up, although the existing acid leaching process has its own advantages, it still has the disadvantages of high content of impurity ions in the leaching solution, large alkali consumption for subsequent pH adjustment, and difficulty in industrialization.