Tunnel kiln reduction roasting method of high-valence manganese oxide ores

Abstract

A tunnel kiln reduction roasting method of high-valence manganese oxide ores includes evenly mixing the high-valence manganese oxide ores and sulphur to obtain a mixture; placing the mixture into a closed reaction tank and using a tunnel kiln for heating, reduction roasting and cooling; and cooling a roasting product under an air-free condition, using a dilute sulphuric acid solution to leach the roasting product, performing solid and liquid separation and subjecting a filtrate to purifying and impurity removing to obtain a manganese sulfate solution, wherein a leaching rate of manganese is over 90%. According to the tunnel kiln reduction roasting method of the high-valence manganese oxide ores, defects of high energy consumption and large dust capacity of existing reduction processes of a coal based rotary kiln method, a reverberating furnace method, a fluid-bed furnace / fluidization furnace method and the like are overcome; and the tunnel kiln reduction roasting method has the advantages of being simple in process, convenient to operate, low in cost, high in manganese conversion ratio, suitable for treating various high-valence manganese oxide ores including pyrolusite, psilomelane, hausmannite, braunite and the like and capable of easily achieving industrialization.

Description

technical field [0001] The invention belongs to the field of metallurgy, and relates to a method for reducing and roasting high-priced manganese oxide ore in a tunnel kiln. Background technique [0002] my country's manganese ore resources are mainly divided into two types: manganese oxide ore and manganese carbonate ore. Manganese carbonate ore is mainly used to produce electrolytic manganese, and the technology is mature and widely used at home and abroad. With the development of the manganese industry, the supply of high-quality manganese carbonate ore resources is becoming increasingly tight, which limits the development of the electrolytic manganese industry to a certain extent. High-grade and high-priced manganese ore can be used as a high-quality raw material for the preparation of manganese sulfate and electrolytic manganese in industry due to its low impurity content. However, manganese oxide minerals are generally insoluble or slightly soluble in dilute acid. The...

AI Technical Summary

Problems solved by technology

[0007] The main problems of this method are: the ore roasting chamber is separated from the fuel combustion chamber, and it is difficult to maximize the heat transfer, resulting in low heat utilization; Contains a large amount of dust, which is difficult to handle and is a potential high pollution source; when exhaust gas is discharged, it will easily lead to insufficient reducing atmosphere in the furnace and poor reducing effect

Using this method and equipment can obtain a good reduction effect, but there are still many problems: the required roasting temperature is relatively high, which is 900 ° C ~ 970 ° C; the material is heated outside the tube by fuel combustion, resulting in uneven heating of the material in the tube , and the central material is difficult to heat to the required temperature; the roaster is airtight, and a large amount of gas generated during the roasting process is difficult to handle; the structure of the device is complex, and the gas products are not recycled and treated, and if they are directly discharged, they will pollute the environment

Images