A high-efficiency and energy-saving manganese nitride production process

Abstract

The invention provides a high-efficiency and energy-saving manganese nitride production process. The process directly melts the metal manganese raw material into a liquid state, atomizes it for one nitriding, and then condenses it into a high-temperature powder and then nitriding it for the second time. The production process is short. Manganese nitride powder can be obtained from electrolytic manganese sheet in one step. Combining manganese powder and nitriding into one, the production is easy to realize automatic control, the production efficiency is high, the environmental pollution is small, the comprehensive production cost is low, and the power consumption can be controlled below 380 degrees per ton of product.

Description

technical field [0001] The invention relates to the field of additive production in iron and steel metallurgy, in particular to the production technology of manganese nitride. Background technique [0002] The existing large-scale production of manganese nitride is carried out in large-scale vacuum nitriding furnaces. It is intermittent production. Generally, one batch is produced within 24 hours, and each batch is 4 to 10 tons. The quality is stable and controllable, but there are also The following disadvantages. [0003] (1) High energy consumption for production: 450 kWh of electricity per ton of product (excluding the energy consumption of metal manganese powder production), of which 370 kWh / ton of electricity for electric heating vacuum furnace, 80 kWh / ton of electricity for vacuuming and nitrogen production tons of products. [0004] (2) The overall production process is long and the overall production cost is high: taking manganese nitride powder with the largest m...

AI Technical Summary

Problems solved by technology

[0003] (1) High energy consumption for production: 450 kWh of electricity per ton of product (excluding the energy consumption of metal manganese powder production), of which 370 kWh / ton of electricity for electric heating vacuum furnace, 80 kWh / ton of electricity for vacuuming and nitrogen production tons of product

[0004] (2) The overall production process is long and the overall production cost is high: taking manganese nitride powder with the largest market demand as an example, the intermediate products in the production process are: electrolytic manganese metal sheet (metal manganese block) → metal manganese powder → Forged manganese ball → manganese nitride ball → manganese nitride powder, at least five processes of crushing, mixing, forging, nitriding, and crushing, the overall cost is high

If it is directly nitrided with metal manganese powder, it is easy to sinter into blocks, and it needs to be broken again, and the nitriding effect is poor after sintering into blocks, and the nitrogen content is low

Patent 2013106268813 uses metal manganese powder for direct fluidization and nitriding. Both metal manganese powder and nitrogen gas need to be preheated first. The process parameters of the system are difficult to control, the implementation is difficult, and the production cost is high.

[0005] (3) Heavy environmental pollution: Whether it is manganese nitride powder or manganese nitride ball (pillow), it is necessary to make metal manganese flakes (blocks) into metal manganese powder, and the existing powder making methods are mainly high-pressure roller milling or Ball milling has a lot of noise, and vibrating screening equipment also generates a lot of dust. Although there is a dust collection device, the system is not easy to seal, and the amount of dust leaked is still large, which is harmful to the operators on site and to the surrounding environment. Pollution is also big

[0006] (4) The quality of the product needs to be continuously improved, the content of impurities is high, and there are many oxides containing manganese. Even if the electrolytic metal manganese sheet with high purity is used, the oxygen element content is 2% to 3% after product testing, mainly because of the chemical properties of manganese Lively, although the electrolytic manganese metal sheet has been passivated, it will oxidize and turn black gray after a period of storage. After being crushed into manganese powder, the oxygen element content is 0.5% to 1%, mixed with water glass, forged into balls, and dried After each step, manganese oxide is newly generated, making the oxygen content as high as 2.5% to 3%.

There is also a technical proposal to flush hydrogen-containing reducing gas such as ammonia cracking gas into the furnace, and the manganese oxide produced by reduction can only be reduced to a small part and the production cost is high.

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