SU1447414A1 - Method of flotation of coal - Google Patents

Abstract

The invention relates to the enrichment of minerals and m. used in coal preparation plants. The goal is to increase the yield and quality of the concentrate. The pulp is preconditioned initially, ala with a water-soluble cationic polyelectrolyte based on ethyleneimine and epichlorohydrin (PEI), and then with semi-coking resins of sapropelites. The ratio of semi-coking and PEI resins is from 1: 0.007 to 1: 0.02. After the pulp has been conditioned, flotation of coal is carried out. The PEI reagent is a product of the polymerization of ethyleneimine, initiated by epichlorohydrin, and is a slightly yellow viscous liquid with a molecular weight of 0, 2.0-10. The activity of PEI is associated with its molecular weight. When the molecular weight is less than 0.5-10, there is no flocculating activity. A molecular weight greater than 2.0-10 causes a decrease in solubility. The structural element of PEI has the form .. -Cj H -NH-C n -N-CjH -NH -.... The amino groups —NH and —NH, j adsorb onto the surface of the coal particles and help to fix the latter on air bubbles due to the effect of charge neutralization. This creates conditions for the formation of microflocks. At the same time, the efficiency of aggregate formation depends on the content of sapropelite semi-coking resins in the pulp. 1 hp f-ly. a (l nli 4 4

Description

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

The purpose of the invention is the higher yield and quality of the concentrate,

In the method of coal flotation using saproplite semi-coking resins, before conditioning the coal fines with resins, a water-soluble cationic polyelectrolyte based on ethyleneimine and epichlorohydrin (PEI) in an amount of 0.7-2.0 wt.%, T. e. at a ratio of 1: 7 10 to: 2.0-1оЛ

Polyethylenimine is a product of polymerization of ethyepimine, initiated by epichlorohydrin, and is a slightly yellow viscous liquid with a molecular weight of OsS-1O of 2.0 to 10. At the same time, the activity of polyelectrolyte is primarily associated with its molecular weight; the lower limit (0.5-10) is limited by the loss of flocculating activity, and the upper limit (2.0: 10) is limited by the dissolution of the flocculation and the complexity of the synthesis.

The repeating structural element PEI can be conventionally represented by the formula:

. ,.-C H -Nll-CjH-N-CjH -NH-,. "

The cationic activity of PEI is due to the presence of primary and secondary amino groups —NH- and NH2-j, which adsorb onto the surface of the coal particles, contribute to the fixation of the latter on air bubbles due to the effect of charge neutralization. In this case, conditions are created for the aggregation of micron-sized particles and the formation of microflocks. The pressing 45 hydrodynamic force is proportional to the cube of the radius of the aggregate and increases 10 times during flocculation, which ensures the fixation of the aggregates on the bubble, 50

The optimal concentration of PEI in i ulpe corresponds to 0.7 to 2.0 wt.% Of the resins. With a lower content of PEI, the efficiency of aggregate formation decreases, and with greater observation of the stabilization of the sludge due to the hydrophilization of the surface of the coal particles.

Q 5

0 5

0

five

50

PRI me R. To carry out the process, we take a portion of the coal and mix it with water in a laboratory machine of the type Mechanobr. Then, a solution of PEI is fed, mixed, and an emulsion of semi-coking resins of sapropelites is added. After the sample is in contact with coal, air is supplied to the flotation machine and flotation is carried out.

The efficiency of flotation assessed

T And

in terms of E 7J where

K V - yield of flotation concentrate,%;

And, AIJ - respectively, the ash content of the flotation concentrate and waste,%.

The addition of PEI together with resins. Pulping of sapropelites increases flotation process performance: the yield of flotation concentrate increases from 82.0 to 83.6%, with its ash content decreasing from 8.1 to 7.9% and the ash content increasing from 72.5 to 78 , 0%. The efficiency ratio of using PEI together with semi-coking resins of sapropelites during the coal wood flotation is 825 versus 734 in the case of using only resins.

In addition, the ability of the sediment of the flotation concentrate during its filtration is improved by structure-forming; the moisture content of the sediment decreases from 28.5 to 26.7%.

Thus, the use of the method allows to increase the concentrate yield by 1.6% and reduce its ash content by 0.2%.

Claims (2)

Invention Formula 1, The method of coal flotation, including preconditioning of a feedstock with saproselite semi-coking resins containing paraffinic and alkyl aromatic hydrocarbons, characterized in that water-soluble cationic polyelectrolyte is introduced into the conditioning before the sapropelite semi-coking resins. ethyleneimine and epichlorohydrin, while the ratio of semi-coking resins of sapropelites and water-soluble polyelectrolyte based on ethyleneimine and epichloro hydrine is from I: 0.007 to 1: 0, 02. .7 4l / .H 2. The method according to claim 1, exc. (1 h-electrolyte based on ethyleneimine and y and y by the fact that molecular zichlorohydrin is from 0, the mass of soluble to thionic poly is up to 2.010.