Titanium ore acidolysis method through sulfuric acid process

Abstract

The invention relates to an improved method for the titanium ore acidolysis through sulfuric acid in the process of producing titanium white through a sulfuric acid process. The method is characterized in that: the method comprises the following steps: firstly premixing dilute waste acid produced by titanium white production after concentration and trash extraction with the titanium ore; and then adding the premixed ore slurry into an acidolysis pot, and then adding concentrated sulfuric acid so as to initiate a main reaction through the dilution heat produced by the added concentrated acid. The method has the advantages of: 1) improving the reutilization amount of titanium white waste acid and reducing the cost of concentrated waste acid; 2) removing a sulfuric acid cooling link so as to simplify the operation; 3) improving the operational conditions of premixing and acidolysis so as to reduce the risk of technical accidents; and 4) strengthening the premixing intensity, improving the premixing effect, so that the acidolysis reaction is sufficient and the acidolysis rate is remarkably improved.

Description

technical field [0001] The invention relates to an improved method for sulfuric acid acid hydrolysis of titanium ore, in particular to a production method for returning waste sulfuric acid produced in the sulfuric acid titanium dioxide production process to the sulfuric acid titanium dioxide acid hydrolysis process. technical background [0002] Titanium dioxide is a high-quality white pigment widely used in coatings, plastics, paper, ink, chemical fiber, food, electronics and other fields. In 2006, the world's output exceeded 5 million tons. It is an important inorganic chemical product. The production of titanium dioxide usually uses two production processes: sulfuric acid method and chlorination method. The sulfuric acid method titanium dioxide process began around the 1920s. Because the raw materials are easy to obtain and the technology is relatively mature, it is widely used in China. However, the sulfuric acid method titanium dioxide production The comprehensive utili...

AI Technical Summary

Problems solved by technology

There are following problems in this operation process: first, in order to facilitate the infiltration of concentrated sulfuric acid to titanium ore powder, concentrated sulfuric acid must be pre-diluted, after part or all of the concentrated sulfuric acid is carried out pre-diluted (generally diluted to the concentration of 88-93%) , that is, to mix acid, the diluted concentrated sulfuric acid should be further cooled before it can be pre-mixed with all the mineral powder, and the steps are complicated

[0005] The flow process of this existing concentrated waste acid reusing still can't overcome following shortcoming: 1) because the sulfuric acid concentration that requires dropping into acidolysis pot is higher than the initial concentration of acidolysis reaction, generally requires more than 4% greater than the acidolysis reaction initial concentration, In order to ensure that sufficient dilution heat is generated to initiate the main reaction after adding initiating water, therefore, in the process of utilization of dilute waste acid, in order to meet the process requirements, it has experienced the process of concentration and dilution, cooling and heating successively, resulting in high energy consumption and complicated process; 2) Since the unsafe problem of high concentration of sulfuric acid used in the premixing stage has not been resolved, during the premixing process, if the acid concentration and acid temperature are too high or excessive stirring or premixing time is too long, it will be in the premixing process. Accidents occur due to the acidolysis main reaction during the process. In order to prevent accidents, it is necessary to cool the sulfuric acid and slurry during the acid preparation and premixing process, and to control the mixing intensity and time. Insufficient premixing intensity and time often affect Premixing effect, thus affecting the acidolysis rate of the subsequent acidolysis process; 3) It is inconvenient to pump the premixed slurry with high acid concentration to prevent excessive stirring and trigger the main reaction of acidolysis, so the premixing tank must be set At a position higher than the acid hydrolysis tank, it is convenient to put the premixed slurry directly into the acid hydrolysis tank, however, the investment and energy consumption of inputting the dry mineral powder into the premix tank at a higher position are large

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