What process is used for the production of manganese sulfate by high temperature crystallization? How to use high-temperature crystallization method to produce manganese sulfate? What is the process of high-temperature crystallization for the production of manganese sulfate?
First, the use of manganese sulfate
Manganese sulfate is a very important base manganese salt that is widely used. With the increasing depletion of manganese-rich resources, the production of manganese sulfate has gradually tended to use manganese-containing mass fractions of less than 20% of the lean manganese ore, resulting in low manganese sulfate content in the leaching liquid, and when the atmospheric pressure crystallization method is used to produce manganese sulfate, the evaporation and concentration process needs to consume a lot of steam, resulting in high production costs.
Second, the preparation method of manganese sulfate
At present, the main methods of producing manganese sulfate are high-temperature roasting method, acid immersion method, two-mine acid addition method, sulfur dioxide method and aniline reduction method, etc., the difference between them lies in the difference in leaching process, and its crystallization process is atmospheric pressure evaporation crystallization process.
Third, the characteristics of manganese sulfate
The solubility of manganese sulfate increases with the increase of temperature at temperatures below 27 °C, and gradually decreases with the increase of temperature above 27 °C, especially at more than 100 °C. The solubility curve of manganese sulfate at high temperatures is shown in Figure 1. Using this property of manganese sulfate, low concentrations of manganese sulfate solutions can be made at high temperatures
Fourth, the preparation of manganese sulfate adopts high-temperature crystallization evaporation process
In the production process of manganese sulfate, the high-temperature crystallization method is used to analyze the feed mass concentration, operating temperature, residence time and stirring rate, so as to better use the high-temperature crystallization method to evaporate and crystallize manganese sulfate.
The preparation of manganese sulfate adopts a high-temperature evaporative crystallization process
1. In the crystallization process of manganese sulfate, the operating temperature, the mass concentration of the feed liquid, the residence time and the stirring rate have a monotonous increase in the influence of the crystallinity, and their primary and secondary sequences are: the operating temperature > the feed concentration> the residence time> the stirring rate.
2. Considering the operability and equipment performance of the actual process, the better process conditions when using the high-temperature method for crystallization are: the operating temperature is 170 °C, the mass concentration of the feed liquid is 370 g/l, the holding time is 14 min, and the stirring rate is 350 r/min. Under these conditions, the crystallinity can reach 84.0
3. Compared with the traditional atmospheric pressure crystallization process, the energy consumption of the high-temperature crystallization method is 60.7% of the atmospheric pressure crystallization method, and the steam volume can be saved by 2.75 t per production of 1 t mnso, h, o.
The law has opened up a new way of energy conservation and consumption reduction for the comprehensive utilization of China's lean manganese ore resources, which has good social and economic benefits.