SU1558473A2 - Method of dressing and dehydration of coal - Google Patents

Abstract

THE INVENTION RELATES TO COAL BENEFICIATION AND DEWATERING AND CAN BE USED IN BENEFICIATION OF FLOTATION TAILINGS AND DRAINAGE AND DISCHARGE PRODUCTS OF WATER-SLUDGE MANAGEMENT OF COAL BENEFICIATION PLANTS. THE GOAL IS TO INCREASE THE EFFICIENCY OF THE COAL BENEFICIATION AND DEWATERING PROCESS. FOR THIS, BEFORE MIXING THE COAL WITH OIL, AROMATIC COMPOUNDS ARE INTRODUCED INTO THE OIL IN A QUANTITY OF FROM 5 TO 10% OF THE OIL WEIGHT. BENZALDEHYDE @ AND ITS HOMOLOGUES ARE USED AS AROMATIC COMPOUNDS. AROMATIC KETONES OF THE COMPOSITION @ CAN ALSO BE USED, WHERE R IS A PHENYL RADICAL, R ¹ IS A PHENYL OR ALKYL RADICAL, OR BENZOIC ACID @ AND ITS HOMOLOGUES, OR MONATOMIC PHENOL @ AND ITS HOMOLOGUES, OR BENZOQUINONE @ AND ITS HOMOLOGUES. IN THIS CASE, THE POLARITY DIFFERENCE BETWEEN THE OIL REAGENT AND THE OXIDISED CARBON SURFACE IS SHARPLY REDUCED. THIS LEADS TO STRENGTHENING THE ADHESION BOND BETWEEN THE COAL AND OIL REAGENT. DURING THE MIXING PROCESS, A HYDROPHILIZING REAGENT IS INTRODUCED AND MIXING IS CONDUCTED FOR 2 TO 5 MINUTES. AFTER MIXING, THE FLOCCLES ARE SEPARATED FROM THE ROCK AND WATER BY GRAVITY. THE SEPARATED FLOCCLES ARE GRANULATED IN AN AQUEOUS ENVIRONMENT AT A S:L RATIO OF 1:1.5 TO 1:2 IN THE PRESENCE OF A POLYMER FOLLOWING WITH SUBSEQUENT SEPARATION OF THE GRANULES ON A SIEVE. 5 Z.P.F-LY.

Description

The oil contains aromatic compounds in an amount of 5 to 10% of the oil weight.

As aromatic compounds

chon

and his

use: benzaldehyde (O/homologues; aromatic ketones of the composition where R is phenyl; R1 is phenyl

B-C-B1 I O

or alkyl; benzoic acid O/C and its homologues; monohydric phenol /oU-OH and its homologues; benzoquinone O and its

homologues.

The novelty of the proposed method lies in the fact that aromatic compounds with carbopolarities of the contacting phases are introduced into the oil reagent. This difference, in turn, is determined by the difference in the electric dipole moments of the molecules of the oil reagent and the coal surface. Consequently, when apolar reagent molecules interact with polar oxygen-containing groups on the oxidized areas of the coal surface, weak adhesive bonds coal-oil reagent are formed. Introduction of aromatic compounds with carbonyl, carboxyl, hydroxyl and quinoid groups possessing a significant dipole moment into the oil reagent makes it possible to sharply reduce the polarity difference between the oil reagent and the oxidized coal surface, which in turn leads to strengthening of the adhesive bond coal-oil reagent. In this case, between the surface molecules of coal and the indicated aromatic compounds15

nyl, carboxyl, hydroxyl 20 in addition to universal dispersion dei quinoid groups in the amount of 5-10%

orientational and induction intermolecular van der Waals forces are present, and interactions of a chemical nature arise - hydrogen and donor-acceptor interactions from the mass of the oil reagent; benzo[benzo] are used as aromatic compounds.

and its homologues; aron

ketones composition

in-s-in1 II o

Where

R - phenyl; R - phenyl or alkyl; benzoic acid p/s and its homologues;

-HE

monatomic phenol /oU-OH and its homologues; benzoquinone O and its homologues.

The introduction of aromatic compounds with carbonyl, carboxyl, hydroxyl and quinoid groups into the oil reagent makes it possible to increase the strength of the adhesive contact of the reagent with coal, especially on the oxidized areas of the mosaic coal surface, represented by various oxygen-containing groups with significant bonds. The increase in the strength of the coal-binder adhesive contact promotes an increase in the rate of the oil selection process, as well as a more intensive displacement of water from the coal surface. The enhancement of intermolecular interactions occurs not only at the coal-oil reagent boundary, but also in the reagent itself. This has a decisive effect on the subsequent stage of flocculo formation. As is known, the aggregation of oily coal particles occurs according to the autohesion mechanism due to the interaction of the surface films of the oil reagent. In this case, the balance of intermolecular forces is restored in the contact zone of the films, and the strength of the resulting aggregate is determined by the cohesion of the binding oil reagent. In turn, the cohesion of the reagent is higher, the stronger the intermolecular interactions in it. Consequently, the introduction of the specified aromatic

dipole moment. Widely used in practice oil granules-45 compounds not only increase the strength of the adhesion contact of coal-binder, diesel fuel, etc.) and stone-oil aggregates at the floccule stage - paraffin, naphthenic, di- and what prevents their destruction in the process of mixing and subsequent dehydration. As a result, it is possible to

avoid sharpening of the rock fraction

compounds with a symmetrical molecular structure. As a result, their electric dipole moment is practically zero, and the oil reagents themselves act mainly as apolar substances. In accordance with the DeBruijn rule, known in adhesion theory, the strength of the coal-oil reagent adhesive contact is higher, the smaller the difference

fragments of destroyed floccules, leading to a decrease in the selectivity of the oil selection process.

Thus, the introduction of aromatic compounds with the specified oxygen-containing groups into the oil reagent increases the efficiency of enrichment and

polarities of the contacting phases. This difference, in turn, is determined by the difference in the electric dipole moments of the molecules of the oil reagent and the coal surface. Consequently, when apolar reagent molecules interact with polar oxygen-containing groups on the oxidized areas of the coal surface, weak adhesive coal-oil reagent bonds are formed. The introduction of aromatic compounds with carbonyl, carboxyl, hydroxyl and quinoid groups possessing a significant dipole moment into the oil reagent makes it possible to sharply reduce the polarity difference between the oil reagent and the oxidized coal surface, which in turn leads to strengthening of the coal-oil reagent adhesive bond. In this case, between the surface molecules of coal and the specified aromatic compounds

0 in addition to universal dispersion forces, orientational and inductive intermolecular van der Waals forces act, and interactions of a chemical nature arise - hydrogen and donor-acceptor bonds. An increase in the strength of the adhesive contact between coal and binder helps to increase the rate of oil selection, as well as more intensive displacement of water from the coal surface. Strengthening of intermolecular interactions occurs not only at the coal-oil reagent interface, but also in the reagent itself. This has a decisive effect on the subsequent stage of flocculo formation. As is known, the aggregation of oiled coal particles occurs by an autohesive mechanism due to the interaction of surface films of the oil reagent. In this case, the balance of intermolecular forces is restored in the contact zone of the films, and the strength of the resulting aggregate is determined by the cohesion of the binding oil reagent. In turn, the cohesion of the reagent is higher, the stronger the intermolecular interactions in it. Consequently, the introduction of the specified aromatic

compounds not only increase the strength of the adhesive contact of coal-binder, but also contributes to the strengthening of bonds inside coal-oil aggregates at the flocculation stage, which prevents their destruction during mixing and subsequent dehydration. As a result, it is possible

fragments of destroyed floccules, leading to a decrease in the selectivity of the oil selection process.

Thus, the introduction of aromatic compounds with the specified oxygen-containing groups into the oil reagent increases the efficiency of enrichment and

dehydration of coal by the oil selection method "OVZUMS at all its stages. The introduction of aromatic compounds with carbonyl, carboxyl, hydroxyl and quinoid groups into the oil reagent in an amount of 5-10% of the mass of the oil reagent allows for high efficiency of the enrichment and dehydration process for almost the entire range of products for which processing

the same coal with reagents introduced into it - soda ash (0.6% of the solid mass) and oil for oiling the batch (2% of the solid mass) is mixed in the same mode (2000 rpm) as in the proposed method for 5 minutes. Then the floccules are separated from the waste in a NOGS-325 centrifuge.

The results of the studies show that the introduction of aromatic compounds with carbo-, carboxyl, and hydroxyl compounds into the binder oil reagent is intended for the purpose of the method - flotation waste, 10% aromatic compounds with carbo-, carboxyl, and hydroxyl compounds.

and quinoid groups allows to significantly increase the efficiency of the coal enrichment and dehydration process. This is done in a basic way. In addition, it creates the possibility of reducing the selection time, and therefore increasing the production efficiency of coal enrichment plants.

Example. The process of enrichment and dewatering of flotation waste is carried out in laboratory conditions. The moisture content of the concentrate is reduced by 2-5%, the ash content is increased by 5.5-7.5%, the average size of coal grains is 0-35 μm, the pulp density is 70 g/l. Similar results were obtained when using the devices of the OVZUMS process.

the use of alkyl-substituted homologues of the indicated compounds as additives.

Claims (4)

Formula of invention  1. The method of enrichment and dehydration of coal according to Author's certificate No. 1248661, characterized in that, in order to increase the efficiency of the enrichment and dehydration process, aromatic compounds are introduced into the pulp phase oil in an amount of 2% of the mass of solid coal before mixing. The initial hydraulic mixture with calcined soda and oil introduced into it for oiling the charge with the additive is mixed in a contact tank at a speed of 1/-10 impeller rotation 2000 rpm (linear 35 USE benzaldehyde gb with and its in the amount of 0.6% of the solid mass in the pulp. The oil for oiling the batch produced by Avdeevsky 25 Coke and Chemical Plant was taken as a binding oil reagent. Before feeding the oil reagent into the pulp, an aromatic additive is introduced into it - benzaldehyde in the amount of 7% of the mass of the original oil reagent. Consumption of the oil reagent with the addition of 5 to 10% of the oil mass. 2. The method according to item 1, characterized in that the aromatic compounds speed 6.3 m/s) for 5 min. After 3.4 and 5 min of mixing, samples are taken and the average diameter of the resulting floccules is determined using a microscope. After 5 min of mixing, the product is fed to a NOGS-325 centrifuge, with which the floccules are removed from the hydraulic mixture. The resulting concentrate (cake) is analyzed for moisture using a standard method. The solid phase of the centrifuge is centrihomologized. 3. The method according to item 1, characterized in that aromatic ketones of the composition 40B - C - B are used as aromatic compounds. where R is phenyl; Rx is phenyl or alkyl. 4. The method according to paragraph 1, characterized in that fugues (waste oil selection) after 45 that as aromatic compounds of water evaporation are analyzed for. /0 ash content. benzoic acid is used Su- s Enrichment and dehydration by pre- and its homologues. the patched method is repeated with the addition of 5. The method according to item 1, characterized in that in the oil reagent 3.5, 10 and 12% benzal- that as aromatic compounds of dehyde. Such a series of experiments is carried out on 50 use monoatomic phenol Ou-on each of the proposed aromatic additives. Simultaneously with these experiments on enrichment and dehydration of coal by the proposed method, the process is carried out by a known method, i.e. without introducing the listed aromatic compounds into the initial oil reagent. For this purpose, the hydraulic mixture 55 and its homologues. 6. The method according to item 1, characterized in that the aromatic compounds use benzoquinone O and its homologues. the same coal with reagents introduced into it - soda ash (0.6% of the solid mass) and oil for oiling the batch (2% of the solid mass) is mixed in the same mode (2000 rpm) as in the proposed method for 5 minutes. Then the floccules are separated from the waste in a NOGS-325 centrifuge. The results of the studies show that the introduction of aromatic compounds with carbonyl, carboxyl, hydroxyl groups into the binding oil reagent and quinoid groups allows to significantly increase the efficiency of the coal enrichment and dehydration process. This is manifested in a decrease in the moisture content of the concentrate (cake) by 2-5%, an increase in the ash content by the basic method. In addition, it creates the opportunity to reduce the selection time, and, consequently, to increase the selection productivity by 5.5-7.5% compared to of the devices of the process "OVZUMS Similar results were obtained when Vani coal before mixing in the oil add aromatic compounds in the amount of /-l0 ve from 5 to 10% of the oil weight. 2. The method according to item 1, characterized in that the aromatic compounds homologues. 3. The method according to item 1, characterized in that aromatic ketones of the composition 40B - C - B are used as aromatic compounds. and its homologues. 6. The method according to item 1, characterized in that the aromatic compounds use benzoquinone O and its homologues.