Process for manufacturing iron pellets from low-grade complex refractory ore through molten slag method

Abstract

The invention relates to a process for manufacturing iron pellets from low-grade complex refractory ore through the molten slag method, belonging to the field of direct reduction of metal metallurgy. The invention has the technical scheme that the process comprises the following steps of: fully mixing the low-grade complex refractory ore with a reducing agent and additives, pelletizing, drying the carbonic pellets, adding lime stone, coal dust and clay to mix, pressing the mixture into hollow or solid bricks, spraying clay slurry to the surfaces of the bricks, and loading the bricks into reduction equipment; discharging the reduced product, immediately cooling the product in a cooling protection chamber with reducing atmosphere, and pulverizing and sorting the cooled material product to obtain the raw material for steel making. The invention has the advantages that a slag forming agent promotes non-iron oxide gangue components to be quickly aggregated and remove metal element to form ore slag, and metal aggregation agent promotes oxidized metal metals to be quickly reduced and separate ore slag to form iron pellets. The material forming iron pellets can greatly improve the efficiency of subsequent ore grinding and magnetic separation procedures. By applying the process, the capacity of a single kiln can be increased to the maximum extent.

Description

Technical field [0001] The invention relates to a process for producing granular iron by a low-grade complex refractory ore slag method, which belongs to the field of metal metallurgy direct reduction. Background technique [0002] At present, direct reduced iron is an urgently needed raw material for the production of high-quality pure steel in my country's electric furnace steel, and it is also an urgently needed raw material for the production of high-purity steel casting and forging blanks in my country's equipment manufacturing industry. At present, due to the increase in steel production capacity, the problem of raw materials is particularly prominent, and the utilization of low-grade complex and difficult-to-treat ore has become a hot spot in the metallurgical industry. Low-grade complex refractory ores include: ① low-grade refractory ore such as oolitic hematite, hematite, specularite, limonite, siderite, and antelope ore, ② vanadium-ilmenite, boronite , Laterite nickel ...

AI Technical Summary

Problems solved by technology

BACKGROUND OF THE INVENTION Coal-based direct reduction has been used, and various attempts have been made in the utilization of low-grade complex and refractory ores. Rotary hearth furnaces, rotary kilns, tunnel kiln processes, and shaft furnaces are all involved. Direct reduction is also useful at home and abroad. technology to make low-grade complex and refractory ore into reduced iron. The background technology has disadvantages such as low recovery rate, large investment, high cost, low single kiln output, and environmental pollution.