Method of separation of solid particles

Abstract

FIELD: chemical; mining; processing industries.SUBSTANCE: method for separating solid particles which can be used to separate solid particles by adsorption capacity. The method for separating solid particles includes granulometric separation to obtain fractions by particle size, feeding particles of each obtained granulometric fraction in a uniform layer onto a moving surface, above which, at a distance from the moving surface, cyclones with air intakes are located. The distance between the cyclone air intakes and the moving surface is set at 5-10 mm. They regulate the air flow pressure in the cyclones, sequentially increasing it from 50 to 500 Pa. The permissible deviation in particle size between the obtained fractions of the separated material is preliminarily calculated using the ratio of the difference in the bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material, to the average bulk density of the separated material.EFFECT: reduction in the proportion of impurities in the final product, as well as an increase in the accuracy and efficiency of the method for separating solid particles based on their adsorption capacity.1 cl

Description

[0001] Technical field

[0002] The invention relates to the chemical and mining and processing industries, in particular, to a method for separating solid particles and can be used to separate solid particles by adsorption capacity.

[0003] Technology Level

[0004] Invention WO2016190835A1, "Aerodynamic recirculation separator for bulk materials", IPC B07B 4 / 02, is known, comprising an air blower consisting of an electric motor, an impeller installed in a pipe, which together create an axial fan of the impeller type, and means for setting the direction of the flow at its outlet in the form of a louvered screen, a separation chamber with two inlets and two outlets, a loading hopper, three unloading channels, a return air duct with a number of turning sections, first and second settling chambers. The outlet of the air blower is connected to the first inlet of the separation chamber, the outlet of the loading hopper is connected to the second inlet of the separation chamber, the first outlet of which is connected to the return air duct, and the second - to each unloading channel. The air blower, separation chamber, and return air duct, coupled in series, form a channel through which the air flow is recirculated. The return air duct is divided into several sections.The return air duct comprises at least one horizontally expanding section, connected to the first settling chamber through an opening in the lower wall of the duct. To ensure airflow circulation, some of the turning sections are designed to rotate vertically. The separation chamber is configured to inject air through the discharge channels by directing the airflow upward, away from the discharge channels. The first horizontally expanding section has

[0005] The downwardly curved lower wall of the settling chamber is located in the smooth bend zone from this section to the first turning section, which is configured with an upward turn, and is the only opening in the return air duct that has constant communication with the outside environment. The opening is covered by a row of canopies facing against the air flow. The opening into the second settling chamber is covered by a row of canopies. A draining means, designed as a valve, is located at the bottom of the second settling chamber. An upper air shutoff valve, directed downstream, is installed at the inlet of the first horizontally expanding section on the side opposite the settling chamber. A lower air shutoff valve, directed upstream, is installed in the first turning section, configured with an upward turn, on the side of the opening into the first settling chamber downstream of it.

[0006] The disadvantage of this solution is that the operation of this aerodynamic recirculation separator does not take into account the correlation between bulk density, particle size distribution, and adsorption capacity of solid particles, which allows for accurate separation of solid particles based on their adsorption capacity. (WO2016190835A1, https: / / worldwide.espacenet.com).

[0007] Invention SU 1488029 A2, "Pneumatic Separator for Separating Bulk Materials," IPC B07B 4 / 00, is known. It comprises a loading hopper and a feeder connected via a window to a vertical pneumatic separation channel. A guide chute is hinged at the lower edge of the window. The upper part of the channel is connected to a settling chamber and a fan. A turbulator is installed in the lower part of the pneumatic separation channel. This turbulator consists of two horizontal shafts on which round plates are mounted with equal clearance relative to each other and at an acute angle to the axis of the pneumatic separation channel. Both shafts are positioned symmetrically relative to the vertical axis of the pneumatic separation channel and can rotate in opposite directions.

[0008] The disadvantage of this solution is that the operation of this pneumatic separation device does not take into account the correlation between bulk density, particle size distribution, and adsorption capacity of solid particles, which allows for precise separation of solid particles based on their adsorption capacity. (SU 1488029 A2, http: / / new.fips.ru).

[0009] Invention RU 2067034 C1, "Aerodynamic separator", IPC B07B 4 / 00 is known, containing a loading vibrating hopper with a feeder, installed on a wind tunnel with a pneumatic pump and a valve grid, between which a thermal chamber is located, the wind tunnel, on the one hand, is fixedly introduced into vertical separation columns containing throttle valves, power cylinders, and on the other hand, is telescopically introduced into the vertical separation columns in the form of broken elements with baffle shields, wherein the wind tunnel is equipped with inclined baffle shelves and is introduced into sequentially installed dynamic bioconical separation chambers, the last of which is equipped with a baffle vibrating shield, wherein the top of the columns and chambers is connected to an aspiration system, and the bottom with conveyors, wherein the separator is controlled from a control panel.

[0010] The disadvantage of this solution is that the operation of this aerodynamic separator does not take into account the correlation between bulk density, particle size distribution, and adsorption capacity of solid particles, which allows for precise separation of solid particles based on their adsorption capacity. (RU 2067034 C1, http: / / new.fips.ru).

[0011] Invention RU 2256515 C2, "Multi-frequency vibratory separator system, Vibratory separator containing this system, and Method for vibratory separation of solid particles", IPC B07B 1 / 40, B07B 1 / 42, is known, containing a method for vibratory separation of solid particles including introducing separated solid particles into the separator body through an inlet pipe, applying a single-frequency vibration to the separator body and, thus, to the solid particles through one or more sieves to create a movement of particles along one or more sieves so that the undersize fractions pass through it to the first outlet pipe, and so that the oversize fractions go along it to the second outlet pipe, converting the single-frequency vibration of the separator body, exciting one or more sieves, into a sequence of mechanical pulses applied to the interface device to thereby generate multi-frequency vibration of the sieve and, thus, the masses of agglomerates,processed by one or more sieves, thereby ensuring deagglomeration and preventing blockage of one or more sieves by particles.

[0012] The disadvantage of this solution is that this method of vibration separation of solid particles does not allow for the separation of solid particles by their adsorption capacity, but only by size, while particles of the same size may have different adsorption capacities. This method also does not take into account the correlation between bulk density, particle size distribution, and adsorption capacity of solid particles, which allows for the precise separation of solid particles by their adsorption capacity. (RU 2256515 C2, http: / / new.fips.ru).

[0013] Among the known solutions, invention RU 2282503 C1, "Method for dry processing of coal", IPC B07B 9 / 00, is close to the claimed object, comprising preliminary screening, processing on a classifier, selective crushing and sieving of the processed products on sieves. The material of class 0-25 mm separated on the screen is processed on a classifier, where the class 0-1 mm is separated, and the remaining product of class 1-25 mm is sifted on sieves with a ratio of the sizes of the previous sieve to the next equal to 1.7-2.0. The above-screen material of one class (for example, 1-2 mm) is fed to a conveyor with a mesh belt, where, using nozzles installed above the belt, material with a density of 1250-1350 kg / m3 is sucked out due to the vacuum of air under the first nozzle. 3 , ash content A d =8-11%, under the second nozzle with a density of 1350-1600 kg / m3 3 (A d =11-25%) and under the third nozzle with a density of 1600-1800 kg / m3 3 (A d=25-45%). The nozzle cuts above the belt are set at distances - the first nozzle is the largest, the second nozzle is the middle, and the third is the smallest. The distances are determined empirically. The remaining over-screen material + 25 mm after preliminary screening is subjected to selective crushing with transfer to the 0-25 mm class, separation of the 0-1 mm class from it in a classifier, and subsequent processing as indicated above. The vacuum in the nozzles is the same and amounts to 300-800 mm H2O. The material remaining on the conveyor has a density of 1800-2500 kg / m3 3 is a rock that is sent to the waste heap.

[0014] The disadvantage of this solution is that this method of vibration separation of solid particles does not allow for the separation of solid particles by their adsorption capacity, but only by size, while particles of the same size may have different adsorption capacities. This method also does not take into account the correlation between bulk density, particle size distribution, and adsorption capacity of solid particles, which allows for the precise separation of solid particles by their adsorption capacity. (RU 2282503 C1, http: / / new.fips.ru).

[0015] Essence of the invention

[0016] The objective of the present invention is to reduce the proportion of impurities in the final product obtained by this method, and to increase the accuracy and efficiency of the method for separating solid particles based on their adsorption capacity.

[0017] The stated problem is solved by forming the granulometric composition of solid particles of the separated material by dividing them into fractions based on particle size, while preliminarily calculating the permissible deviation in particle size between the obtained fractions of the separated material based on the ratio of the difference in the bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material, to the average bulk density of the separated material, which makes it possible to increase the accuracy of separation of solid particles based on their adsorption capacity, subsequent aerodynamic separation with a smooth increase in air flow pressure and collection of fractions of solid particles depending on their adsorption capacity.

[0018] The method of separating solid particles is based on the relationship between bulk density, particle size distribution and adsorption capacity of solid particles.

[0019] The method of separating solid particles has the following sequence of actions.

[0020] Calculate the permissible deviation in particle size between the obtained fractions of the separated material using the ratio of the difference in the bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material to the average bulk density of the separated material using the following formula:

[0021] ,

[0022] where Δd is the permissible deviation in particle size between the obtained fractions of the separated material;

[0023] Δρ - the difference in bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material (kg / m 3 );

[0024] ρ ср - average bulk density of the separated material (kg / m3) 3 ).

[0025] The proposed formula for calculating the permissible deviation in particle size between the obtained fractions of the separated material is applicable to solid particles having a shape close to spherical.

[0026] The material to be separated is subjected to granulometric separation to obtain fractions based on particle size, with a resolution of no more than 1 mm, which minimizes the impact of particle size on the accuracy of subsequent aerodynamic separation. Particles of each granulometric fraction are fed in a uniform layer onto a moving surface, above which, at a distance of 5-10 mm from the moving surface, are located the air intakes of cyclones or aerodynamic separators with adjustable airflow pressure. The airflow pressure is adjusted with successive increases from 50 to 500 Pa, establishing an operating mode for the aerodynamic separator in which particles with higher adsorption capacity are separated from those with lower adsorption capacity.Particles with higher adsorption capacity are captured by a collecting cyclone, while particles with low adsorption capacity are left on the moving surface or captured by a separate cyclone at higher air flow pressure.

[0027] The technical result of the proposed solution is a reduction in the proportion of impurities in the final product obtained by this method, an increase in accuracy and efficiency

[0028] a method for separating solid particles according to their adsorption capacity due to the use of the correlation between bulk density, particle size distribution and adsorption capacity of solid particles.

[0029] Implementation of the declared decision

[0030] Calculate the permissible deviation in particle size between the obtained fractions of the separated material using the ratio of the difference in the bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material to the average bulk density of the separated material using the following formula:

[0031] ,

[0032] where Δd is the permissible deviation in particle size between the obtained fractions of the separated material;

[0033] Δρ - the difference in bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material (kg / m 3 );

[0034] ρ ср - average bulk density of the separated material (kg / m3) 3 ).

[0035] It is obtained that during the separation of solid particles of charcoal with Δρ= 30 kg / m 3, which corresponds to 10% of the adsorption capacity of the separated material, the permissible deviation in particle size between the resulting fractions of the separated material should not exceed 0.6. The charcoal to be separated is subjected to particle size separation on a vibrating screen with replaceable meshes, achieving a permissible particle size deviation of 0.6 between the resulting fractions of the separated material, which forms the size step between the resulting fractions. Particles of each particle size fraction of charcoal are fed in a uniform layer onto a belt conveyor, above which, at a distance of 10 mm from the moving surface of the belt conveyor, aerodynamic separators with adjustable air flow pressure are located.The air flow is regulated by gradually increasing its pressure from 50 to 500 Pa, establishing an operating mode for the aerodynamic separator in which particles with higher adsorption capacity are separated from those with lower adsorption capacity. Particles with higher adsorption capacity are captured by a cyclone collector, while particles with lower adsorption capacity are retained on the moving surface.

Claims

A method for separating solid particles, including granulometric separation to obtain fractions based on particle size, feeding particles of each obtained granulometric fraction in a uniform layer onto a moving surface, above which cyclones with air intakes are located at a distance from the moving surface, characterized in that the distance between the cyclone air intakes and the moving surface is set at 5-10 mm and the air flow pressure in the cyclones is regulated, successively increasing it from 50 to 500 Pa, while preliminarily calculating the permissible deviation in particle size between the obtained fractions of the material being separated, using the ratio of the difference in the bulk density of the material being separated, which corresponds to 10% of the adsorption capacity of the material being separated to the average bulk density of the material being separated, using the formula: , where Δd is the permissible deviation in particle size between the obtained fractions of the separated material; Δρ is the difference in bulk density of the separated material, which corresponds to 10% of the adsorption capacity of the separated material (kg / m 3 ); ρ ср - average bulk density of the separated material (kg / m3) 3 ).