SU1319909A1 - Method of dressing silvanite and carnallite ores - Google Patents

Abstract

The invention relates to the technology of flotation enrichment of potash ores and makes it possible to increase the recovery of potassium and magnesium chloride due to the precipitation of magnesium ions from the saline solution. Wet grinding of the ore is carried out. When this happens, cold decomposition of carnallite occurs and the magnesium chloride is dissolved in the solution. The pulp from the solid particles of insoluble i sylvinite residue is deslasticized. Then sylvine flotation is carried out. The enrichment products are dehydrated, and the filter saline solution from the dehydration of NaCl and KCl are combined and fed to the magnesium chloride precipitation step. The deposition of Mg is carried out by introducing into the solution of sodium carbonate in stoichiometric amount to the content of Mg ion. The resulting MgCOj precipitate is separated from the brine. And the circulating salt solution returned to flotation is neutralized with hydrochloric acid in order to remove the residual amount of carbonate from the solution, which deteriorates the solubility of flotation reagents. Entering sodium carbonate into the circulating saline solution makes it possible to precipitate MgCl in the form of MgCO accumulated in the flotation liquor and to reduce the MgClI concentration in the solution from 5–12% to 0.25%. This makes it possible to increase the recovery of KC1 by 3% and eliminate the discharge of chlorine solution. (L Сг5; О СО о QO

Description

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The invention relates to the technology of flotation enrichment of potash ores and can be used in the potash industry in processing mixed sylvite-carnallite ores.

The purpose of the invention is to increase the recovery of potassium and magnesium chloride due to the precipitation of magnesium ions from the saline solution.

The method includes the wet grinding of ore and the cold decomposition of carnallite, the desliming of sylvinite residue, the flotation of sylvite and the dehydration of enrichment products. Then sodium carbonate is added to the salt solution in a stoichiometric amount to the Mg ion content. The resulting precipitate is separated from the brine. The circulating saline solution returned to flotation is neutralized with hydrochloric acid;

Entering sodium carbonate into the circulating saline solution makes it possible to precipitate MgCl4 accumulated in the flotation liquor as magnesium carbonate and to reduce the concentration of magnesium chloride in the solution from 5-12 to 0.25%, which increases the recovery of CS & 3% and eliminates the discharge harmegnium solution. The point of entry of sodium carbonate into the working solution resulting from the dehydration of enrichment products is selected from the condition of obtaining raw materials for obtaining metallic magnesium, not contaminated by impurity of insoluble residue and salt particles of CSE and NaCl. The operation of neutralizing with hydrochloric acid a circulating solution returned to flotation is necessary to remove the residual amount of carbonate from the solution, which deteriorates the solubility of flotation agents.

The introduction of sodium carbonate in a circulating saline solution in an amount exceeding the stoichiometric amount to the content of the Mg ion leads to an increase in the consumption of the precipitant and the cost of the precipitant in the absence of a further increase in the degree of extraction of potassium chloride. With the consumption of sodium carbonate less than the stoichiometric content of Mg ion, the recovery of potassium chloride at the flotation stage is reduced.

The method is carried out in the following manner.

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Example. 500 g of sylvinite-carnallite ore from the Verkhnekamsk potash deposit, containing,%: carnallite 10.2; Cop &30.5; NaCl

50.5; BUT 1.8; the insoluble residue (IO) 7.0 is crushed in sylvinite working solution containing,%:, 5; NaCl 18.5; MgCe 1.75; CaSO0,35, density 1,235 kg / l.

Grinding is carried out at a T: W ratio of 1: 0.8 for 10 minutes to a particle size of 1.0 mm. When this happens, the cold decomposition of carnallite occurs with the release of magnesium chloride in the solution. The concentration of magnesium chloride in the solution is up to 6.70%. A pulp of solids of insoluble sylvine and halite residue is diluted with a working solution to a T: W ratio of 1: 2 and subjected to mechanical desliming in a hydrocyclone and hydroseparator, and then sludge flotation using polyacrylamide (50 g / ton) and hydroxyethyl fatty acids (40 g / t). After clarification, hydrocyclone discharge is directed to the wet grinding stage, the hydrocyclone discharge sludge and sludge flotation machines are washed, thickened, and sent to the dump.

Deslastic sylvinite-halito-. This pulp is diluted with a circulating silvinitic solution to the ratio

T: G 1: 2.5, is contacted with flotation reagents for 1.0 min and sent to flotation in a mechanical flotation machine. In the solid phase fed to the flotation of a suspension, 147.8 g of KSK are contained; 249 g of NaC and 2.8 g of N. O; and in the flotation solution, the concentration of the components is,%: KCE 9.6; NaCg 18.3; MgC6g l, 2; CaSO 0,36. For flotation use

hydrochloric acid amine C 2 g with consumption of 40–50 g / t and blowing agent T-66 with consumption of 10–15 g / t. Foam and chamber flotation products are dehydrated by filtration, with halite being sent to the dump, and the potassium chloride is dried.

The filter solution from dewatering NaCE and CWS is combined and in the amount of 1000 g is fed to the stage of precipitation of magnesium chloride. The deposition of Mg is carried out by introducing into the filter solution a 6.5% sodium carbonate solution, previously prepared

in purified salt solution from Mg.

The amount of 6.5% sodium carbonate solution fed to the precipitation is 237 g, which corresponds to the stoichiometric amount of the ion content. The precipitation of Mg is carried out in a precipitating reactor with stirring of the filter and precipitating solutions drained for 5 minutes. The mixture of solutions and the MgCO precipitate are sent to the thickener, while adding polyacrylamide at a rate of 80 g / t to accelerate the precipitation.

A portion of the clarified solution of a carbon dioxide in the amount of 222 g is fed to the dissolution of sodium carbonate in a separate solvent and a 6.5% preparation is prepared.

+ 7.

Mg precipitating solution. Wherein

15.4 g are added to dissolve. Another part of the clarified solution of the thickener in the amount of 738 g is neutralized with 36% hydrochloric acid solution, for which 5.7 g of hydrochloric acid is added to the saline solution. The resulting solution, containing 0.25% MgC6, is fed in the amount of 600 g per flotation, and the remainder in the amount of 138 g is sent for wet grinding of sylvinite-carnallite

ore

The precipitated MgCOj condensed in the thickener is filtered and subjected to a double washing with water. As a result, the compiler L.Katochkina Editor A.Lezhnina Tehred V.KadarCorrector S.Cherni

2549/7

Circulation 511 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, Projecto st., 4

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five

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SILV {nitro-carnallite ore grades yield 145.5 g of product, containing:%: potassium chloride 95.7; HjO 1.0; AND ABOUT. 1.3; NaCE 2.0 and 10.76 g of MgCO precipitate containing 93.5% of the basic substance. The degree of extraction of the COP is 91.0%, and the degree of extraction of the ion is 82.0%.

The resulting magnesium carbonate after washing contains 93.5% of the basic substance.

Claims (1)

Invention Formula The method of enrichment of svinvinito-carnallite ores, including wet grinding of ore and cold decomposition of carnallite, ensuring the sylvinite residue, flooding of sylvite, dehydration of enrichment products, into saline solution ovrate, which, in order to increase the recovery of potassium chloride, in order to increase the recovery of potassium chloride and to reduce the amount of potassium chloride to the flotation stage. due to the precipitation of magnesium ions from the saline solution, after dehydration of the enrichment products, sodium carbonate in stoichiometric amount is introduced into the circulating saline solution to the ion content, The resulting precipitate is separated from the brine, and the circulating saline returned to flotation is neutralized with hydrochloric acid.