Integrated calcination method for dealkalization and magnetization of Bayer process red mud

A Bayer red mud and dealkalization technology, applied in the field of comprehensive utilization of solid waste, can solve the problems of high cost and difficult promotion

Inactive Publication Date: 2016-02-17
SHANDONG JIANZHU UNIV
View PDF6 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, although the methods of magnetizing or dealkalizing red mud

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Integrated calcination method for dealkalization and magnetization of Bayer process red mud

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0017] Red mud, lime, and coal powder are mixed according to the ratio of 100:15:25. After mixing evenly, they are roasted in a roasting furnace. After roasting at a furnace temperature of about 1200°C for 10 minutes, they are taken out and cooled rapidly under the action of cold water. After roasting, The material is crushed and ground to -200 mesh, more than 80%, and then separated by a magnetic separator under the condition of an induced magnetic field of 5500Gs. The results obtained are as follows:

[0018] Table 1. Iron element recovery form in red mud

[0019] Composition (wt%) Yield(%) Iron content (%) Recovery rate(%) Red mud raw material 100 18.09

Red mud after roasting and separation 13.81 72.80 55.58

[0020] Table 2. Element content composition of red mud before and after roasting

[0021] Composition (wt%) SiO 2 Al 2 o 3 Fe 2 o 3 CaO K 2 o Na 2 o P 2 o 5 Red mud raw material 21.6 21....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for calcination dealkalization and magnetization of Bayer process red mud, and relates to a treatment and utilization technology for waste-red mud produced in the aluminum oxide industry. The method aims at conducting reduction on sponge iron and magnetite or dealkalization on the red mud; based on the principle that the temperature spot of red mud magnetization calcination and the temperature spot of red mud dealkalization calcination are similar, 5%-20% of a dealkalization agent and 5%-25% of a reducing agent are added into the Bayer process red mud and calcinated at a temperature ranging from 1,100 DEG C to 1,240 DEG C at the same time, and calcinated materials are ground to separate out the sponge iron and magnetite with the iron content larger than 55% and dealkalized red mud with the alkali content smaller than 2%. The extracted sponge iron or magnetite can be used as raw materials in the ferrous metallurgy industry, the dealkalized red mud can be widely applied to the field of building materials, and extremely high actual application value is achieved. Tailing-free utilization of the red mud is really achieved, and a new technical route is provided for comprehensive utilization of the red mud.

Description

technical field [0001] The invention relates to the treatment and utilization technology of red mud, a waste material produced in the alumina industry. Specifically, it uses Bayer process red mud as the main raw material, adopts a roasting process, and performs magnetization in the process of dealkalization of red mud, which belongs to solid waste The field of comprehensive utilization. Background technique [0002] The red mud produced by the alumina industry has caused great harm to the environment due to its strong alkalinity and large output. In 2012, my country produced 37.696 million tons of alumina, accounting for about 37-40% of the world's total output, and produced more than 40 million tons of red mud, with a cumulative stockpile of nearly 300 million tons; international red mud is mainly disposed of by stockpiling and covering soil At present, the effective utilization of red mud is mainly based on: adopting the red mud dealkalization technology with simple operat...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C22B1/02
CPCC22B1/02
Inventor 房永广刘冰清冯奇伟邵斌巩孝颖
Owner SHANDONG JIANZHU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap