Granulated potassium sulfate production process
FIELD: inorganic substances technology.
SUBSTANCE: invention relates to production of granulated potassium sulfate appropriate for use in chemical industry for manufacturing mineral fertilizers and in agriculture as chlorine-free potassium-containing fertilizer. Process according to invention comprises spraying binding component onto dry potassium sulfate powder while simultaneously mixing materials in granulator mixer followed by drying thus formed granules to residual moisture not exceeding 1%. As binding component, liquid potassium soap or 50% solution thereof is used on the basis of 8 g binder per 100 g potassium sulfate. Once spraying of binding component ended, dry potassium sulfate is supplied through screw feeder to support growth of granules.
EFFECT: enabled production of granulated potassium sulfate in the form of non-caked and non-dusting product with stable granulometric composition and loose density, which contains high amount of basal substance (at least 51% K2O).
2 cl, 2 tbl
The invention relates to a technology for simple chlorine-free potassium fertilizers, in particular granular potassium sulfate used in the chemical industry in the production of mineral fertilizers, as well as in agriculture to increase yields of many crops are adversely affected by chlorine ion.
There are a large number of methods for producing potassium sulfate using as raw material natural potash ores. So, there is a method of production of potassium sulfate by reacting potassium chloride with sulfuric acid in mechanical muffle furnace at a temperature of 500-550°C. By this method have a highly pure potassium sulfate, however, the necessity of using sulfuric acid limits its spread in the industry. The disadvantage of the product obtained in this way is unstable particle size, high flaking, caking during storage and transportation .
Closest to the invention to the technical essence and the achieved effect is a method for granulated potassium sulfate by wetting the finished powder product water, okutyvaya in rotating drums or disc granulators and further drying the obtained granules .
The disadvantage of this method is to obtain granules of n is high strength, prone to fracture under impact loading, transportation and handling.
The aim of the invention is to provide a method for granulated potassium sulfate with improved consumer properties.
This goal is achieved by a method for granulated potassium sulfate, based on the dispersion of the binder component to the dry powder of potassium sulfate while stirring in a mixer-granulator, followed by drying the obtained granules to a residual moisture content mass fraction of not more than 1%. A distinctive feature is that, as a binder component used liquid potash glass or 50 wt.% aqueous solution per 100 g of potassium sulfate not less than 8 g of the binder. In addition, to ensure the growth of the granules after spraying a binder through a screw feeder serves dry potassium sulfate.
This set of features of the method is new and involves an inventive step, as it provides improvement of consumer properties of sulphate of potash.
The method is as follows:
Example No. 1.
The potassium sulfate in the form of dry powder is placed in a mixer-granulator, include the drive chamber and the drive rotor granulator. From a mechanical atomizer serves binder: liquid glass, an aqueous solution of liquid is about glasses, the water content in the product moisture not more than ≈13%.
The results of the experiments are shown in table 1.
|The size of the pellet (fraction)||No EXPERIENCE|
|No. 1 dry product: potassium sulfate||No. 2 dry product: potassium sulfate||No. 3 dry product: potassium sulfate||No. 4 dry product: potassium sulfate|
|binder: water||binding: 50% aqueous solution of liquid glass (1:1)||binding: liquid glass||binding: 65% aqueous solution of liquid glass|
|The contents of fractions|
The obtained pellets of potassium sulfate is subjected to drying to a residual moisture content mass fraction of not more than 1%. After spraying the binder and the formation of germ granules through a screw feeder serves a dry powder of potassium sulfate to ensure the continued growth of the granules.
Comparative tests of solubility of potassium sulfate and potassium chloride in water.
Tested the following product samples:
- Potassium chloride HUNDRED SPECS - 001-98 mark,
Mass fraction of potassium in terms of K2About 60.2 percent, dynamic strength - 93%.
Manufacturer of OJSC "Uralkali".
- A prototype of granulated potassium sulfate.
Mass fraction of potassium in terms of K2About 51.1 percent; the Content of impurities: Cl 0,4%; N, no; Na 0,24%; Mg+2no; CA+20,03%; insoluble the STATCOM 2,77%; dynamic strength is 94%.
Manufacturer LLC Soda-chlorate"
Manufacturer JSC "Azot".
The methodology of the tests.
- mixer "Ecros 8100 with a two-bladed propeller stirrer (length of the blade 25 mm, height 10 mm);
- glass with an inner diameter of 55 mm, with a capacity of 250 cm3secondome.
For tests used the fraction of products with a particle size of 2-3 and 3-4 mm In a glass beaker with 100 cm3water under stirring with a frequency of 5 Rev/sec has introduced a portion of the test product in the amount of one gram and turned on the stopwatch. The end of the process of dissolution was determined visually by the disappearance of the particles of the solid phase at the bottom of the Cup (the movement of water-insoluble substances in the upper zone of the solution). The results are given in table 2.
|Sample||Fractions, mm||Statistical strength, kg/Gran||Dynamic strength, %||The number of dimensions||The time of dissolution, min|
|3-4||4||1.1 to 1.2|
The proposed method provides receiving granular potassium sulfate in the form of a crystalline non-caking and non-dusting product with a stable particle size and bulk weight, with a high content of the basic substance - K2On no less than 51%. The use of liquid potash glass as a binder provides not only high strength of the resulting pellets, but also allows to obtain a product with a high content of the target component To2Oh and by the absence of impurities. Obtained by the proposed method, the granules have a high measure of dynamic strength (94%) and durability.
Positive test results confirm the high strength of granules of potassium sulfate, obtained by the proposed method.
The soil application of granular potassium sulfate provides a prolonged effect of fertilizer due to slow dissolution of the granules, in addition, decreases with Epen ash product with stormwater runoff and wind.
The examples demonstrate the industrial applicability and the effectiveness of the proposed method.
Sources of information
1. Pechkovsky CENTURIES, Alexandrovich oil on canvas, and other Technology potash fertilizers, Minsk, High school 1968, p.28-29, 90, 225, 184.
1. Method for granulated potassium sulfate, comprising spraying a binder on a dry powder of potassium sulfate while stirring in a mixer-granulator, followed by drying the obtained granules to a residual moisture content of not more than 1%, characterized in that the binder component used liquid potash glass or 50 wt.% aqueous solution per 100 g of potassium sulfate not less than 8 g of the binder.
2. The method according to claim 1, characterized in that after spraying a binder through a screw feeder serves dry potassium sulfate for growth granules.
FIELD: nonferrous metallurgy; methods of reprocessing of a sodium-potash solution.
SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to reprocessing a sodium-potash solution produced from a nepheline ore with a low molar index of potassium alkali. The method provides for a concentrating evaporation of the initial sodium-potash solution, a subsequent its evaporation with separation in sediment of monohydrate sodium, separation of a potassium sulfate from a monohydrated soda mother liquor with a dosing in it of a sodium sulfate or sulfuric acid to convert a superfluous in the production process potash into a potassium sulfate, separation from the potassium sulfate mother liquor of the waterless soda polluted with impurities of potash, potassium sulfate and potassium chloride. The waterless soda polluted with impurities of potash, potassium sulfate and potassium chloride is subjected to conversion by a solution a concentrated evaporation at the temperature of 60-70°C within 2.0-3.0 hours with a dosage of 1.2-1.5 m3 of the concentrated evaporation solution per one ton of the waterless soda with production of the monohydrated soda purified from of impurities of a potash, a potassium sulfate and a potassium chloride. The invention allows to reduce a specific consumption of a vapor in the production cycle and the flow of the solution and soda at conversion and separation of monohydrated soda.
EFFECT: the invention allows to reduce a specific consumption of a vapor in the production cycle and the flow of the solution and soda at conversion and separation of monohydrated soda.
FIELD: nonferrous metallurgy; processing of sodium sulfate solutions.
SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy, in particular, to processing of sodium sulfate solutions, which are released into a slime storage after a gas cleaning treatment electrolysis of bodies by production of aluminum. The method of processing of sodium sulfate solutions produced after the gas purification of the electrolysis bodies at production of aluminum provides for the gases purification from sulfuric oxides and fluorides by their sprinkling with a sodium sulfate solution in the washers, extraction from the solution after the gas purification of the fundamental quantity of sodium fluoride in the form of cryolite. The sodium sulfate solution purified from cryolite is in addition purified from sodium fluoride by its treatment at the temperature of 95-105°С within 1.5-2.0 hours with a lime milk injected into the sodium sulfate solution at the rate of stoichiometric binding of fluorine contained in the solution in CaF2. The sodium sulfate solution purified from fluorine is further subjected to a concentrating evaporation till achieving the density of a product solution of 1.37±0.02 g/l and extract a sodium sulfate from it into the sediment a in the form of berkeyit salt by introduction in the product solution of a carbonate soda till achieving the concentration of the titratabic alkali in the mother liquor of 215-230 g/l Na2Ot and the density of the solution in the suspension up to 1.35±0.02 g/l at stirring of the suspension at temperature of 95-100°С within 30-40 minutes. The invention ensures a more complete extraction of sodium sulfate from the product sodium sulfate solution in the form of berkeyit salt purified from sodium fluoride.
EFFECT: the invention ensures a more complete extraction of sodium sulfate from the product sodium sulfate solution in the form of berkeyit salt purified from sodium fluoride.
FIELD: nonferrous metallurgy and inorganic compounds technology.
SUBSTANCE: invention is dealing with processing of carbonate solution produced in complex procedure of nepheline feed into alumina and soda products. Manufacture of soda comprises dissolving double salt in evaporation-concentrated carbonate solution, which is further concentrated to form soda suspension, which is divided, by the aid of hydraulic classification method, into two streams. Each of them is separated into soda and soda mother liquor. Soda mother liquors are combined and treated to separate potassium sulfate. Potassium sulfate mother liquor is concentrated to give double salt suspension. Precipitated double salt is separated. Purity of soda product is 98-98.5%.
EFFECT: increased purity of soda product.
FIELD: non-iron metallurgy, in particular crystallizing of sodium sulfate.
SUBSTANCE: sodium sulfate from solution of electrolytic aluminum manufacturing is recovered by saturation of gas cleaning solution with sodium sulfate, cooling of obtained solution with cooler, and precipitate separation. Cooling of sulfate containing solution to 8-120C is carried out in refrigerator through a wall, and cooling to 0-(-2)0C is carried out by direct contact with cooler.
EFFECT: increased refrigerate durability, seduced labor cost, equipment cost, and energy consumption.
8 cl, 1 tbl, 3 ex
FIELD: mineral fertilizers.
SUBSTANCE: invention relates to granulated mineral fertilizers containing ammonium phosphates modified by surfactants and powdering substances, which do not lose their physicochemical properties during transportation and storage. Manufacture process comprises granulation of ammonium phosphate pulp, drying of granules, sorting and selection of commercial fraction, cooling and addition of modifying supplements. The latter are added in the cooling stage into zone with bed temperature by 5-10°C exceeding temperature of cooled product. Conditioning additives utilized can be either only liquid or the same mixed with dry powdering substances.
EFFECT: improved quality of surface coverage and simplified process.
2 cl, 3 ex