Production method of metal chromium

Abstract

The invention discloses a production method of metal chromium. The production method includes the following steps that 1, chromium sesquioxide and aluminum powder are evenly mixed, and a mixed material is obtained; 2, an electrode is inserted into a smelting furnace, and then part of the mixed material is put in the smelting furnace; 3, the electrode is subjected to ohmic heating, the temperaturein the smelting furnace rapidly rises, and an aluminothermic reduction reaction is carried out; 4, after the interior of the smelting furnace reaches designated smelting temperature, the rest of the mixed material is put in the smelting furnace, the aluminothermic reduction reaction is carried out, the reaction is constant for a certain time, and it is guaranteed that the reaction is complete; 5,the electrode is powered off, heating stops, and the electrode is pulled out of the smelting furnace; and 6, the smelting furnace is cooled, subjected to slag removal, finished and broken, and the metal chromium product is obtained. Electric heating replaces a heating agent autothermal reaction, reaction conditions can be stabilized according to the aluminothermic reaction condition, the reactionuniformity is good, the consumption of an aluminum reducing agent is reduced by 20%, and the chromium yield is increased by 5% or above.

Description

technical field [0001] The invention relates to a method for producing metal chromium, in particular to a method for producing metal chromium by an electric thermite method. Background technique [0002] Metal chromium is widely used in glass coating, steel alloy, coating target, aerospace materials, steam turbines and other fields. The current production methods of metal chromium include thermite method, electrolysis method and carbon reduction method. [0003] The products produced by the electrolysis method have high purity, but the power consumption is high, the pollution is serious, the production cost is high, and a high-temperature hydrogen deoxygenation device needs to be built to meet the requirements, and the product application range is limited. [0004] The carbon reduction method requires a special high-vacuum reduction furnace and complex high-vacuum equipment. The unit capacity is small, the reaction time is long, and the power consumption is high, so it is n...

AI Technical Summary

Problems solved by technology

[0003] The products produced by the electrolysis method have high purity, but the power consumption is large, the pollution is serious, the production cost is high, and a high-temperature hydrogen deoxygenation device needs to be built to meet the requirements, and the product application range is limited

[0004] The carbon reduction method requires a special high-vacuum reduction furnace and complex high-vacuum equipment. The unit capacity is small, the reaction time is long, and the power consumption is high. It is not suitable for large-scale production.

[0005] The traditional thermite method uses chromium trioxide and alkali metal salt heating agent. The reaction is completely self-heating, and the control stability is poor. The chromium yield is about 85-88%. At the same time, the alkali metal salt heating agent will increase the introduction of impurities. amount and increase the consumption of aluminum powder, which affects the product quality, and the alkali metal salt eventually enters the smelting slag, seriously affecting the added value of the smelting slag

Patent application numbers are "2012104266768", "2014105285553", "201710376145.5", etc. Although the heating method has been optimized and innovated to ensure the stability of the reaction conditions, alkali metal salts are still used as heating agents, which affects the quality of metal chromium products and the value of by-products , in addition, in the process of thermite preparation, the purity and cleanliness of the raw material chromium trioxide used will have a significant impact on the purity of the back-end metal chromium, and the purity or cleanliness of the used chromium trioxide is not high In the case of the situation, the purity of the prepared chromium metal is not high, and the conversion rate of the chromium metal is not high