Iron-containing red mud coal-based direct reduction process and system

Abstract

The invention discloses an iron-containing red mud coal-based direct reduction process and system. Drying and levigating are carried out on red mud and high-volatile coal, blending is carried out on the red mud, the high-volatile coal, a binder and a metal aggregating agent according to the mass ratio of 1: 0.25-0.35: 0.01-0.03: 0.01-0.03, water is added for pelletizing after uniform mixing, carbon-containing pellets with particle size being 20 mm-25 mm are obtained; and the carbon-containing pellets are dried and then conveyed to a rotary hearth furnace, reduction roasting is directly carriedout, reducing is carried out on the red mud through H<2> generated through sufficient pyrolysis of the high-volatile coal and H<2> generated through a carbon gasification reaction with H<2>O as a gasifying agent, the hearth temperature is controlled to be 1250 DEG C-1280 DEG C, the roasting time is controlled to be 30 min-35 min, and the red mud can be sufficiently reduced. According to the iron-containing red mud coal-based direct reduction process and system, the red mud is efficiently reduced by adopting a hydrogen metallurgy process, and the iron-containing red mud coal-based direct reduction process and system have the advantages of high hearth heat transfer efficiency, high iron oxide reduction speed, high single-furnace capacity, high product quality and essential emission reduction.

Description

technical field [0001] The invention belongs to the technical field of metallurgy and mineral engineering, and relates to an iron-containing red mud coal-based direct reduction process and system. Background technique [0002] Red mud is a strong alkaline solid waste produced after alumina or aluminum hydroxide is produced from bauxite. The utilization rate of red mud in China is only 4%, and most of them are stored in yards or dams by wet storage, which not only takes up a lot of land, but also causes serious environmental pollution, and a large number of valuable elements contained in red mud have not been recycled. . Reasonable treatment and efficient utilization of red mud not only meet the requirements of environmental protection, but also contribute to the sustainable development of human society. [0003] Red mud is rich in valuable metals such as iron, aluminum, titanium, etc. 2 o 3 Form exists, the particles are very fine, and the water content is high. Accordi...

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Problems solved by technology

[0009] In view of the above technical problems, the object of the present invention is to provide a coal-based direct reduction process and system of iron-containing red mud, which can solve the problems of high reduction temperature, long reduction time, low metallization rate of reduced materials, grinding and separation problems in the direct reduction process of red mud. The problem of low iron grade and low metal recovery rate of the product can safely and economically produce H 2 , and H 2 Used in the direct reduction of red mud

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