Method for preparing iron ore concentrate by using microwave to deoxidize weak-magnetic iron minerals

Abstract

The invention discloses a making method of concentrate iron ore, which comprises the following steps: (1) adding 5-25% ferric powder or ferric mud into disposed powder evenly; (2) placing material into reducing sintering furnace to sinter for 2-8 min through microwave; reducing weak magnetic ferric ore into magnetic ferric ore; (3) proceeding magnetic cobbing to obtain the product.

Description

technical field [0001] The invention relates to a method for preparing iron concentrate by reducing weak magnetic iron minerals with microwaves from low-grade refractory iron oxide ores containing weak magnetic iron minerals and industrial wastes containing iron. Background technique [0002] my country's iron ore resources are mostly low-grade paragenetic iron ore, in which strong magnetic magnetite and weak magnetic hematite, limonite, siderite, and gangue minerals such as iron-containing silicate often co-exist together. In addition, in a large amount of iron-containing industrial waste, iron mainly exists in the form of weakly magnetic iron minerals, which is a valuable secondary iron ore resource. For example, my country discharges nearly 10 million tons of pyrite slag every year, which generally contains 30% to 50% iron; my country's alumina plants discharge more than 1.8 million tons of red mud every year, which contains 23% to 27% iron. If a large amount of iron-con...

AI Technical Summary

Problems solved by technology

The existing problems are low heat exchange and mass transfer efficiency, high carbon consumption and high production cost

However, for low-grade iron ore, because it contains a large amount of gangue minerals that do not absorb microwaves, it will affect the heating rate of microwave heating and the reduction reaction efficiency. If the microwave carbon thermal reduction process is used, a large amount of coke or charcoal will be consumed, resulting in excessive cost high