A method for reducing strong alkalinity of red mud

Abstract

This application discloses a method for reducing the strong alkalinity of red mud, which belongs to the technical field of red mud resource utilization, and solves the problem of the large amount of acidic solution used in the alkaline regulation of red mud, strong corrosion, high cost, and a large amount of difficult to handle The problem of low recovery rate of waste liquid and red mud. The method of reducing the strong alkalinity of red mud includes: using a crusher to crush the biomass raw material into biomass powder; transporting the biomass powder, water and catalyst into the mixing tank for stirring to obtain a mixture; adding the mixture to the high-pressure reaction Heating the high-pressure reactor and keeping it warm; then cooling to room temperature to obtain a hydrothermal carbonization product; separating the hydrothermal carbonization product from solid and liquid to obtain hydrothermal charcoal and hydrothermal charcoal liquid; mixing hydrothermal charcoal liquid and red mud into the stirring tank, stirring, and then performing solid-liquid separation to obtain modified red mud with reduced alkalinity in the solid phase. The present application realizes the reduction of strong alkalinity of red mud.

Description

technical field [0001] The application relates to the technical field of red mud resource utilization, in particular to a method for reducing the strong alkalinity of red mud. Background technique [0002] Red mud is an industrial solid waste produced in the alumina production process. According to different production processes, red mud is mainly divided into Bayer red mud, sintering red mud and combined red mud. Due to bauxite raw materials, production processes, etc. Due to different factors, there are certain differences in the composition, properties, and phases of the red mud produced; with the continuous growth of alumina production, the global stock of red mud is also rising, and the global red mud discharge has reached 2.6 billion in 2007. Ton. With the continuous growth of the demand for the development of the aluminum industry in China, the output of alumina has also increased rapidly. It is estimated that the discharge of red mud in my country in 2009 has exceed...

AI Technical Summary

Problems solved by technology

Different treatment technologies or methods of red mud must solve the problem of strong alkalinity of red mud. Strong alkalinity is a key issue restricting the comprehensive treatment or resource utilization of red mud. The existing technology generally uses acidic solutions such as hydrochloric acid, sulfuric acid, and nitric acid. Treatment, dealkalization of acidic solution simultaneously destroys the chemical structure of red mud and leaches a large amount of metal elements, resulting in the loss of red mud components; there are problems such as strong corrosion of acidic solution, large amount of waste liquid, and high cost; the generated acidic waste liquid contains a large amount of harmful Metal, hazardous and difficult to handle

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