Efficient low-consumption red mud comprehensive utilization method

Abstract

The invention discloses an efficient low-consumption red mud comprehensive utilization method. The method comprises the following steps that red mud and water are stirred for slurry mixing, then filter pressing is performed to obtain red mud with alkali removed in advance; the red mud with the alkali removed in advance is mixed with a reducing agent and a calcium-containing additive for pellet pressing manufacturing, a pellet material undergoes preheating and high-temperature melting, the molten product undergoes crushing and magnetic separation to obtain reduced iron and furnace slag which can be used as a compound fertilizer raw material. According to the method, the comprehensive utilization of the red mud can be realized, the reduced iron and compound fertilizer raw materials with relatively high additional value can be obtained, moreover, the red mud treatment process is simple, the raw materials are easy to obtain, the operability is high, the energy utilization rate is high, thecost is low, and relatively good economic and social benefits can be generated.

Description

technical field [0001] The invention relates to a red mud treatment method, in particular to a high-efficiency and low-consumption red mud comprehensive utilization method for simultaneously obtaining reduced iron and compound fertilizer raw materials by using the red mud, and belongs to the fields of metallurgy and environmental protection. Background technique [0002] Red mud is an industrial solid waste that is discharged after refining alumina from bauxite. According to statistics, the average production of 1t Al 2 o 3 , will produce 1 ~ 2t red mud incidentally. Red mud can be divided into Bayer red mud, sintering red mud and combined red mud. The chemical composition of red mud produced by different processes is different. Take Bayer red mud as an example, which generally contains 3-20% SiO 2 , 2-8% CaO, 10-20% Al 2 o 3 , 30-60% Fe 2 o 3 and trace ~ 10% TiO 2 Wait. As the world's largest producer of alumina, my country discharges tens of millions of tons of r...

AI Technical Summary

Problems solved by technology

Chinese patent (CN201510471394.3) discloses a method for comprehensive utilization of sulfuric acid slag and red mud. In this method, sulfuric acid slag, red mud, and reducing agent are mixed, roasted and separated to obtain iron powder. However, the production tailings are not fully utilized, and there are Waste of data; Chinese patent (CN201710291417.1) relates to a comprehensive utilization method of alumina red mud. Iron oxide is reduced to iron, so that sodium oxide is reduced to metal sodium, so as to achieve the purpose of alkali removal and alkali recovery, and at the same time, other valuable substances are reduced to metal state and form alloy with aluminum, so as to realize the harmless treatment of red mud and the recovery of valuable elements. Comprehensive recycling, but this method has a long process flow, and the vacuum reduction process has high requirements for production equipment, large investment, and high cost; Chinese patent (201710126298.4) discloses a comprehensive utilization method of red mud, that is, the red mud is first Mix with calcium dealkalization agent, add water and stir to make red mud-calcium dealkalizer mixed pulp, red mud-calcium dealkalizer mixed pulp and sulfur-containing flue gas countercurrent contact in the tower to absorb sulfur dioxide and desulfurize flue gas The red mud mixed slurry is discharged from the top of the tower, and the red mud mixed slurry is discharged from the bottom of the tower. The red mud mixed slurry is further processed to obtain ordinary Portland cement. This method can simultaneously realize the utilization of industrial waste, efficient desulfurization of flue gas, efficient dealkalization and recycling of red mud, etc. It has many benefits, but it is not suitable for factories without sulfur-containing flue gas, and cannot be popularized and applied in a large area, which has certain limitations; The red mud magnetization roasting comprehensive utilization system and process of magnetic separation and separation steps, which improve the comprehensive utilization rate of red mud by optimizing and improving the magnetization roasting equipment, and the final products are iron ore powder and building materials, so as to realize the mass processing of red mud