SU1567278A1 - Method of flotation of coal - Google Patents

Abstract

This invention relates to the flotation of minerals. The goal is to increase the extraction of combustible mass in the concentrate and reduce the consumption of reagents. For this, coal is pre-pulped. Then the pulp is conditioned with a collector and a blowing agent and a combustible mass is recovered. At the same time, vat residues from the production of octamethyltrisiloxane (OMTS) are introduced as a collector-foamer. The OMTS reagent is a colorless or slightly yellowish transparent liquid. The use of DFM in coal flotation solves the problem of waste disposal. The high polarization of the reagent molecules, caused by the electron-withdrawing properties of oxygen atoms, causes good foaming properties. High hydrophobic activity and good foaming properties of the bottoms of OMTS production ensure their high flotation properties. Removing the combustible mass into concentrate when using OMTS during flotation increases from 78.5 - 92.7% to 92.7 - 94.0% with a simultaneous decrease in reagent consumption by 1.5 - 2.0 times.

Description

This invention relates to the enrichment of minerals by flotation and can be used in coal preparation plants.

The purpose of the invention is to increase the recovery of the combustible mass into the concentrate while reducing the consumption of reagents.

The method of coal flotation includes preliminary pulping and conditioning of the pulp with the collector and foaming gel followed by

release of the combustible mass, as a complex collector-foaming agent, in the process introduces the bottom residue of production of octamethyl trisiloxane ().

The composition of the cubic residue of octamethyl-trisiloxane,%:

(CHj) 5SiOSi (CN}) 2OSi (CH3), 20-25

OSi (CH3) 3-5

(CH5), (CH3) 3 "

OSi (CH, h 45-50

OSKCH,)

2-0

Unspecified impurities, presumably composition

(SI,), SijOSKCHj), x "OSi (CHj) 3 (, 4,5) 30-15 Physico-chemical characteristics Boiling point, С Indicator of pre20

hacking, n 2

20

18b-28b

1, 3900-1.3980 0.8480-0.8520

Density, d4

The VAT residue produced by OMTS is formed during the synthesis of valuable reagent - octamethyltrisiloxane is a colorless or slightly yellowish transparent liquid and is currently not disposed of. Thus, the use of VAT residue from the production of OMTS during coal carbonization allows to solve the problem of waste disposal. Example. To carry out the process, we take a portion of coal, for example, 100 g, mixed with water in a laboratory machine of the type Mechanobr with a chamber volume of 0.75 liters for 120 seconds, then a portion of the complex reagent, the bottom residue of the octamethyltrisiloxane production, is supplied and it is contacted with coal pulp for 60 seconds. After 60 seconds, the reactants are brought in contact with the pulp in a flotation machine. for 60 seconds, the flotation concentrate will be removed.

The air supply to the pulp is stopped and the next portion of the complex reagent is supplied, followed by their preparation with coal for 60 s. After contacting the coal sample with reagents, the water is re-fed to the pulp and the second concentrate is removed, the total consumption of reagents and the amount dispensed into the pulp is determined by their flotation activity.

The results of the flotation of coal fines coming to enrichment under the conditions of the coal preparation plant make it possible to establish that using the bottom residue produced by OMTS instead of tractor kerosene with COBS as a complex reagent increases the extraction of the combustible mass into concentrate from 78.5 - 92.7% to 92.7-94.0% while reducing reagent consumption from 0.565-0.900 kg / t to 0.450-0.560 kg /

ten

15

20

25

30 35

672784

With an equal consumption of reagents of 0.560 kg / t, the use of bottoms of OMTS production allows to increase the concentrate yield from 67.2 to 82.0% compared with the use of tractor kerosene with bottoms of butyl alcohols. The improvement in coal flotation using the bottoms of the OMTS production is explained by the elemental composition and molecular structure of chemical compounds present in the technical product.

In molecules of organosilicon acetals and acyclic siloxanes, electron density is localized at oxygen atoms, as a result, reagents can specifically interact with sorption-active centers of the coal surface that carry positive charge (protonized hydrogen atoms of phenolic carboxyl groups in the macromolecule of organic coal) according to the scheme

R-0- (Si-0) nSi-0-R

H

+5

V5

where R is methyl.

In the molecules of silicone acetals and acyclic siloxanes, there are hydrocarbon radicals that can interact with the apolar centers of the coal surface due to the intermolecular Wander-Waals forces.

Therefore, in the case of adsorption on the coal surface of acyclic siloxanes and silicone acetals present in the reagent, both specific (H-bonds, etc.) and universal non-specific intermolecular forces of interaction with the positive and apolar regions of carbon surface. This determines their high value and adsorption energy on the coal surface. At the same time, organosilicon compounds are very good hydrophobicators of the mineral surface upon their adsorption, which positively affects their photoactivity. The presence of 2 or more oxygen atoms in the molecules of acyclic siloxanes

and organosilicon acetals cause high surface activity of bottom residues of OMTS. High polarization of the reagent molecules, caused by the electron-acceptor properties of oxygen atoms, causes good foaming properties.

High hydrophobic activity and good foaming properties of the bottoms from the production of octamethyltrisiloxane ensure their high flotation properties.

Consequently, the use of bottoms produced by OMTS as a complex reagent during flotation allows for an increase in extraction of 1567278

combustible mass in concentrate from 78.5-92.7Z to 92.7-94.0% with a simultaneous decrease in reagent consumption by 1.5-2.0 times.

Claims (1)

Invention Formula The coal flotation method, which includes preliminary pulping, pulp conditioning with a collector and a blowing agent, and the release of a combustible mass, characterized in that, in order to increase the recovery of the combustible mass in the concentrate and reduce the consumption of reagents, it introduces bottoms octamethyltrisiloxane as a foaming collector.