RU2579201C1 - Method of producing potassium humate and facility - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: method of producing potassium humates includes grinding of brown coal, mixing it with potassium hydroxide to obtain working mixture, stirring of the working mixture and its separation into solid and liquid phase by settling, whereupon the brown coal is crushed to particle size of not more than 200 mcm in the presence of water with production of coal-water pulp which is mixed with potassium hydroxide. All components are taken at definite ratio. Device for producing potassium humates comprises hammer mill with unit for feeding brown coal and ball mill for producing water-coal pulp with the unit feeding preliminarily milled brown coal and water, reactor for producing working mixture with facility to feed water-coal pulp, equipped with a mixer, facility to supply potassium hydroxide, as well as setting bath with unit to feed working mixture and remove potassium humate solution.

EFFECT: invention enables to create a method of producing potassium humates, simple in implementation and with lower power consumption.

6 cl, 1 dwg, 2 ex

Description

The invention relates to technologies and devices for the production of organic fertilizers and plant growth regulators and can be used mainly in the chemical industry and agriculture.

Humates along with humic acids form the chemical basis of soil humus, while humus is the basis of activity and stability of most biochemical soil processes.

It was found that humates provide the supply of nutrients, stimulate plant growth, protect them from heavy metals and toxic substances, etc.

There is a method of producing alkali metal humates by ultrafine dispersion of coal containing humic acids in the presence of a chemical additive - dry sodium and / or potassium carbonates [RF Patent No. 2036190, IPC C05F 11/02]. The use of dry sodium and / or potassium carbonates in the dispersion of coal in high-tension mills allows for a solid-phase exchange reaction in which the hydrogen cation in the humic acids contained in the initial coal is replaced by a sodium and / or potassium cation with the formation of water-soluble humates of sodium and / or potassium.

There is also known a method of processing coal, including grinding natural oxidized coal and treating it with an alkali solution, and before leaching, the coal is mixed with sawdust in a ratio of 1.5-2.5: 1, and a stack is formed from the resulting mixture and treated with alkali by irrigation [ RF patent No. 2193547, IPC C05F 11/02].

A known method of producing humic fertilizers from coal, according to which the coal is subjected to ultrafine grinding in a mixture with chemical additives, which are used as alkali metal hydroxides and / or urea, while the initial mixture before grinding is conditioned by humidity to a moisture content of 6-12 wt. % [RF patent No. 2104988, IPC C05F 11/02]. This method allows to obtain a powdery product containing up to 80-83% of humates in soluble form.

The disadvantages of this method are the restrictions on the raw material base in the content of humic acids in the coal of at least 78% and the presence of an insoluble residue in an amount of 15 to 20%, which clogs the nozzles when spraying the solution.

A known method for producing humates of alkali metals, including ultrafine grinding of coal containing humic acids in a mixture with a chemical additive containing compounds of alkali metals, while the oxidizing agent is added to the mixture fed to grinding in the ratio with coal, 0.04-0.05 : 1, and the chemical additive to the technological process is supplied in two stages: at the first stage - during grinding with coal and an oxidizing agent, and at the second - with stirring until a homogeneous mass with the product obtained after grinding is obtained, at the volume of alkali metal carbonates is used as a chemical additive at the stage of grinding coal with an oxidizing agent, and alkali metal hydroxides are used at the mixing stage, then the resulting homogeneous mass is treated under pressure of 3 · 10 ⁵ -4 · 10 ⁵ Pa with a solution of plasticizer and wetting agent [RF Patent No. 2275348, IPC C05G 1/00, C05F 11/02]. As an oxidizing agent, potassium permanganate, or hydrogen peroxide, or potassium peroxide, or calcium peroxide, or sodium superoxide is used. As a chemical additive at the stage of ultrafine grinding, potassium and / or sodium carbonates are used in the ratio with coal (0.01-0.1): 1. Potassium and / or sodium hydroxides in a ratio with coal of 0.13-0.1 are used as a chemical additive in the mixing stage. As a plasticizer, a 30% urea solution is used, which in the ratio to coal is 0.003-0.03. As a wetting agent, a 0.001% surfactant solution is used, which in relation to coal is 0.0001-0.00015: 1.

A known method of producing potassium humate, in which brown coal is dried in air and crushed to 8 mm and add to it a solution of potassium hydroxide from 1 to 5% by weight and mix until a homogeneous suspension is obtained, which is heated to a temperature of from 60 to 100 ° C and maintain this temperature for 2-8 hours in a reaction vessel for dissolving humic acids, and the pH of the solution is maintained continuously at a level of 8 to 12, after which the suspension is placed in a sump and, after settling, the clear liquid is separated and dried to obtain m of solid material [Indian Patent No. 201577, IPC B01J 20/24].

This method of producing potassium humates is the closest to the proposed method and is adopted as a prototype of the invention. The disadvantage of the prototype is the complexity of the technology for producing potassium humates and high energy costs, in particular, going to the drying of the final product to a solid state.

The invention solves the problem of creating a method for producing potassium humates, simple to implement and with lower energy costs.

The problem is solved in that a method for producing potassium humate is proposed, including grinding brown coal, mixing it and potassium hydroxide to obtain a working mixture, mixing the working mixture and separating it into solid and liquid phases by settling, in which brown coal is crushed to a size of no more 200 microns in the presence of water to obtain a coal-water pulp, which is mixed with potassium hydroxide so that the working mixture contains, mass. %:

Coal 3.00-15.00 Water 80.00-95.00 Potassium hydroxide 1.00-5.00

Lignite is mainly crushed in two stages: in the first stage - to a size of not more than 5 mm, and in the second stage - to a size of not more than 200 microns and in the presence of water.

Mixing the working mixture is carried out at a temperature of not more than 70 ° C.

Brown coal in the presence of water is crushed in a ball mill.

Brown coal is pre-crushed in a hammer mill.

The problem is also solved by the fact that the proposed installation for the production of potassium humates, which implements the method described above, comprising a sequentially installed hammer mill with a means of feeding brown coal into it, and a ball mill with a means of feeding it pre-crushed brown coal and a means of supplying water to it , a reactor with a means for feeding water-coal pulp into it, equipped with a stirrer, and a means for entering potassium hydroxide into it, and also a precipitation bath with a means for entering it and means for removing a mixture of potassium humate solution.

In FIG. 1 shows a diagram of the process and its installation, where 1 is a hammer mill, 2 is a ball mill, 3 is water, 4 is a reactor, 5 is potassium hydroxide, 6 is a precipitation bath, 7 is a stirrer, 8 is potassium humate.

Humates of potassium are prepared as follows.

Brown coal preliminarily purified from impurities is subjected to preliminary grinding, for example, at a hammer mill 1, to a fraction size of not more than 5 mm at natural humidity without additional drying.

Next, fine grinding of coal is carried out to a fraction size of not more than 200 microns. Since extraction is carried out from a water-alkaline solution, fine grinding is carried out in the presence of water 3. To do this, use a wet ball mill 2. To achieve the required quality of grinding coal, the following indicators are important: the ratio of the mass of water and coal, grinding time, degree of filling the working volume of the mill. Optimum conditions are ensured if the ratio of water: coal is not less than 1: 1. The filling volume of the mill with water-coal pulp and grinding bodies should not exceed 30%. In this case, the required coal fraction size of not more than 200 microns is achieved with a grinding time of at least 70 minutes.

The required amount of potassium hydroxide solution 5 is poured into a chemically stable reactor 4 equipped with a stirrer at a temperature of not more than 70 ° C and the mixing mode is switched on. The required amount of water-coal pulp is loaded into the reactor with constant stirring of the resulting mixture with a mixer 7. The working mixture obtained by mixing the above ingredients should have the composition (wt.%):

Coal 3.00-15.00 Water 80.00-95.00 Potassium hydroxide 1.00-5.00

The working mixture of the above composition is poured into a settling tank - precipitation bath 6. The settling tank is closed and the working mixture is kept in it for 20 days. During this time, under the influence of gravity, its separation occurs. In this case, the ash part and unreacted particles of coal and organics fall to the bottom in the sediment. Soluble potassium humates and fulvic acid salts remain in the upper layer. After the settling period, the upper layer 8 is separated from the sediment.

The result is potassium humate 8 with characteristics that meet the requirements for it. It is contained in the solution, which facilitates its use - to obtain the desired concentration, it simply needs to be diluted with water.

This method of obtaining potassium humates consists of a small number of stages, less energy-consuming than the prototype, while it allows you to get the target product, ready for use.

Example 1

Brown coal, purified from impurities, is subjected to preliminary grinding, in a hammer mill, to a fraction size of 5 mm at natural humidity.

Next, fine grinding of coal is carried out for 1 hour to a fraction size of 200 microns or less in a wet ball mill.

A potassium hydroxide solution is poured into a chemical reactor equipped with a stirrer at a temperature of 30 ° C, and the mixing mode is turned on. Next, a water-coal pulp is loaded into the reactor with constant stirring. The working mixture obtained by mixing the above ingredients has the composition (wt.%):

Coal 3 p.m. Water 80.00 Potassium hydroxide 5.00

After completion of the supply of the entire volume of hydrogen peroxide to the working mixture, the mixing of the working mixture is stopped. The working mixture of the above composition is poured into a settling tank. The settling tank is closed and the working mixture is kept in it for 20 days. During this time, under the influence of gravity, its separation occurs. In this case, the ash part and unreacted particles of coal and organics fall to the bottom in the sediment. Soluble potassium humates and fulvic acid salts remain in the upper layer. After the settling period has elapsed, the upper layer is separated from the precipitate.

Example 2

The same as in Example 1, but the working mixture has the composition (wt.%):

Coal 3.00 Water 95.00 Potassium hydroxide 2.00 Coal 2 p.m. Water 75.00 Potassium hydroxide 1.00

Claims (6)

1. A method of producing potassium humates, including grinding brown coal, mixing it with potassium hydroxide to obtain a working mixture, mixing the working mixture and separating it into solid and liquid phases by settling, characterized in that brown coal is crushed to a size of not more than 200 microns in the presence of water to obtain a coal-water pulp, which is mixed with potassium hydroxide so that the working mixture contains, mass. %:
Coal 3.00-15.00 Water 80.00-95.00 Potassium hydroxide 1.00-5.00 2. The method according to p. 1, characterized in that the brown coal is pre-crushed to a size of not more than 5 mm 3. The method according to p. 1, characterized in that the stirring of the working mixture is carried out at a temperature of not more than 70 ° C. 4. The method according to p. 1, characterized in that the brown coal in the presence of water is ground in a ball mill. 5. The method according to p. 2, characterized in that the brown coal is pre-crushed in a hammer mill. 6. Installation for the production of potassium humates, including a successively mounted hammer mill with brown coal feed means and a ball mill for producing water-coal pulp with preliminary crushed brown coal feed means and water supply means in it, a reactor for producing a working mixture with a means of supplying water-coal pulp to it, equipped with a stirrer, a means of entering potassium hydroxide into it, and also a precipitation bath with a means of entering the working mixture and a means of removal astvora potassium humates.

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