SU1685532A1 - Method for coal flotation - Google Patents

Abstract

The invention relates to the enrichment of minerals and m. used in coal preparation plants. The aim of the invention is to increase the recovery of the combustible mass into the concentrate. For this, in the method of coal flotation, which includes pulp conditioning with a collector and a blowing agent and the subsequent extraction of coal into a frothy product, bottom residues from the production of methylphenyl polysiloxanes are used as a collector. The presence of oxygen atoms in the molecules of silicon-organic compounds contained in the bottoms from the production of methylphenyl polysiloxanes gives them a high surface activity. Electron-acceptor properties of oxygen atoms cause good foaming properties. As a result, the high flotation properties of said reagent-collector are provided. The application of the method will increase the extraction of combustible mass in the concentrate by 3.9%. (Ls

Description

The invention relates to the field of mineral processing by flotation and can be used in coal preparation plants.

The purpose of the invention is to increase the recovery of combustible mass into the concentrate due to the fact that in the coal flotation method, which includes preliminary pulping and conditioning of the pulp with collector and frother followed by separation, the bottom residue of methylphenyl polysiloxane production is introduced into the process.

The group chemical composition of the bottoms of methiphenylpolysiloxanes production includes

C6H5Si OSI (CH3)

Si (CH3VO С6Н. 0ЧС6Н5 0 Si (CH3) 3

sr si-

II

oh oh

I

Si (CH3) 3 SifCHjV,

(CH3) s5 —O — Si (CH3) s — hexamethyldi-siloxane

Example. To implement the method, we take a sample of coal, for example, 100 g.

00

ate gju y

sew with water in a laboratory machine of the type Mekhanobr with a chamber volume of 0.75 l for 120 s, then a portion of the collector's reagent is fed — bottom residues from the production of methylphenyl polysiloxanes and contacted with coal pulp for 40 s, and then a portion of the foaming agent is introduced - distillation residues from the production of butyl alcohols and, after 20 seconds of contacting the reagents with the pulp, air is supplied to the flotation machine, and then the flotation concentrate is removed for 60 seconds.

The air supply to the pulp is stopped and the next portion of reagents is supplied with their subsequent contacting with coal for 60 s.

After contact of the coal sample with reagents, air is poured into the pulp and the second concentrate is removed, the total consumption of reagents and the amount of dosing into the pulp is determined by their flotation activity.

The results of the flotation of coal fines, which are supplied for enrichment under the conditions of the coal preparation plant of the Magnitogorsk Metallurgical Combine, allowed us to establish the following.

Using as a reagent a collector of the bottoms residue produced by the production of methylphenyl polysiloxanes instead of tractor kerosene allows to increase the extraction of the combustible mass in the concentrate from 88.0 - 91.3 to 91.5-95.2%,

The improvement in coal flotation using the bottoms from the production of methylphenyl polysiloxanes is explained by the elemental composition and structure of their molecules.

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

R-0- (Si-0) n-Si-0-R

i i

n +

H + 8

In the organosilicon molecules, there are hydrocarbon radicals that can interact with the apolar centers of the coal surface due to the intermolecular Vander-Waals forces. Therefore, in the case of adsorption on the coal surface, aliphatic and cyclic organosilicon ethers appear simultaneously as specific

(H-bond, etc.) as well as universal non-specific intermolecular forces interacting with the positive and apolar portions of the coal surface. In this case, organosilicon compounds

are very good water repellents for the mineral surface when they are adsorbed, which has a positive effect on their photoactivity. It should be noted that the presence of oxygen atoms in molecules

The organosilicon compounds contained in the bottoms from the production of methylphenyl polysiloxanes give them high surface activity. The 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 cubic stats of methylphenyl polysiloxane production ensure their high flotation properties.

The use of bottoms from the production of methylphenylpolysiloxanes as a collector reagent during flotation increases the extraction of the combustible mass in the concentrate from 88.0-91.3% to 91.595, 2%.

Claims (1)

Invention Formula The method of coal flotation, which includes conditioning with a collector and a blowing agent and the subsequent extraction of coal into a froth product, characterized in that, in order to increase the extraction of the combustible mass into the concentrate, methyl residues of methylphenyl polysiloxane production are introduced as a collector.