SU1328293A1 - Method of dewatering carnallite - Google Patents

Abstract

The invention relates to methods for the dehydration of chlorine magnesium salts containing crystallization water. In order to increase the degree of dehydration and reduce the content of magnesium oxide in the target product by reducing the degree of hydrolysis of magnesium chloride, the dehydration is carried out in a suspended state in a drying tube at a flow rate of the heat transfer gas to the working volume of 7.0 - 40.0 m / s , while the relative speed of movement (VQT-) between the coolant gas (VT) and dewatering e-. my carnallite (V f support, based on the conditions of V from tgt - VKOP 5 m / s, VOTH Vr, r J table. (L (CX) to CD 00

Description

The invention relates to methods for the dehydration of magnesium chlorides containing water of crystallization, and can be used in non-ferrous metallurgy.

The aim of the invention is to increase the degree of dehydration and decrease the content of magnesium oxide in the target product by reducing the degree of hydrolysis of magnesium chloride in the process of dehydration.

Example 1. The dehydration of carcallite hexahydrate crystalline hydrate (40.0 wt.% And 0.0 wt.% MgO) is carried out in a suspended state during the continuous flow of the heat carrier gas and the dehydrated material in the dryer tube with a capacity of 15 tons / day (dehydrated carnallite). The temperature of the heat carrier gas at the entrance to the working volume of the pipe-dryer is 500 ° C, the speed of the coolant at the entrance is 7.0 m / s.

The relative speed of movement between the coolant gas and the carnallite to be dehydrated by;: is 5.0 m / s (VPTH 5.0 m / s)

V

y-y

 7.0 m / s, i.e. V

rel GET

The carnallite at the outlet of the dryer pipe has a temperature of 220 C. The residual water content in the dehydrated nallite is 3.0% by weight, and magnesium oxide is 1.7% by weight.

The resulting product is sent to the final dewatering in a melted state.

An example (known). Carnallite hexahydrate hydrate is loaded into a fluidized bed furnace with a capacity of 15 tons per day. The dehydration is carried out in a suspended state during the cross-movement of the heating gases and the material, with varying length (from the input of the raw material to the output of the finished product) temperature of the gas - heat carrier in the range of 400 - 500 ° C and the rate of input of the heat carrier gas in the working volume ovens О „6 - 2.0 m / s. The relative speeds of movement between the heat-carrier gas and the dehydrated carnallite V V |. - V ,, д in the fluidized bed are equal to the velocities of the input of the heat exchanger gas into the working volume of the furnace and, therefore, equal to 0.6-2.0 m / s. Heating the product to 220 C, get dehydrated carnallite with residual water content

4.5 wt.% And magnesium oxide 2.0 wt.%. The resulting product is sent for final dehydration and chlorination in the molten state of the fluidized bed formed in the furnace.

hydrolysis products,

The table shows the results on the dehydration of carnallite under various experimental conditions.

The proposed method, in comparison with the known, allows reducing the content of magnesium oxide in dehydrated carnallite by 15-30%, water - by 20-30%. ,

Claims (1)

Invention Formula thirty The method of dehydration of carnallite in a suspended state by contacting it with a heat-transfer gas is about the same and so that, in order to increase the degree of dehydration and decrease the magnesium oxide content in the target product due to 35 reducing the degree of hydrolysis of magnesium chloride, the process is carried out in a drying tube at a flow rate of the heat-transfer gas 7, 0 m / s, and the relative velocity of the heat-transfer gas and dehydrated carnallite is maintained, based on 45 VfH V,., - V ,, m / s, V ,,,. V,. ,,  heat carrier gas velocity j vi "p is the speed of carnallite being dehydrated.