Method for reutilizing acidolysis tailings during producing of titanium dioxide

Abstract

The invention discloses a method for reutilizing acidolysis tailings during producing of titanium dioxide. The method includes following steps: subjecting acidolysis acid residue in the process of producing titanium dioxide through a sulfuric acid process to settling press-filtering and then magnetic separation through a magnetic separator for standby use, extracting rutile from waste residue after magnetic separation through a hydrocyclone, and sending rutile to a titanium-enriched material workshop; premixing titanium concentrate and concentrated sulfuric acid in an acidolysis pot accordingto a certain proportion; mixing acidolysis tailings after concentration and diluted sulfuric acid in a premixing tank according to a certain proportion to obtain initiating acid, and pumping the initiating acid into the acidolysis pot to initiate acidolysis reaction. Compared with other acidolysis titanium residue reutilization processes, the method has the advantages that titanium resources can be recycled sufficiently, and ilmenite and rutile in the waste residue are recycled; acidolysis rate is increased; no new impurity is introduced, and no pollution is caused; equipment is simple and easy to operate, diverse and comprehensive recycling of waste is realized with low investment, and the method has good economic benefit.

Description

technical field [0001] The invention relates to the technical field of titanium dioxide production, in particular to a method for reusing acid hydrolysis tailings in the production process of titanium dioxide. Background technique [0002] After acidolysis and settlement of ilmenite or high-titanium slag, a layer of relatively dense mud is formed at the bottom of the settling tank, the middle is a transition layer with a low concentration of mud formed by settlement, and the top is relatively clear supernatant. After the clarified titanium solution is transported, the rest of the sedimentation tank is generally the transition layer and the following part, which is called acid hydrolysis waste residue, which is a dark loose porous solid substance. According to statistics, the production of 1 ton of titanium dioxide produces about 0.3-0.6 tons of acidolysis waste residue. Generally, the output of acidolysis waste residue is related to the properties of raw materials and acidol...

AI Technical Summary

Problems solved by technology

In the patent of Publication No. CN106115778A, the acid hydrolysis tailings obtained by hydrocyclone selection, wet ball milling, pressure filtration and drying are mixed with sulfuric acid and then pumped into the acid hydrolysis pot with titanium concentrate. The selection effect of the hydrocyclone is worse than that of the magnetic separation recovery, so the purity of the tailings selected is relatively low, which is not conducive to improving the utilization value of the tailings

In addition, the hydrocyclone can only select titanium concentrate, which will cause waste of rutile in titanium slag

In this patent, the tailings can only be obtained after four steps of selection, ball milling, pressure filtration, and drying, and then used for acidolysis reaction, which requires a lot of equipment and consumes a lot of energy.