SU1556544A3 - Method of agglomerating iron-ore material for sintering - Google Patents

Abstract

The invention relates to the agglomeration of iron ore materials and can be used in the production of iron ore pellets. The aim of the invention is to improve the quality of raw granules. A mixture consisting of bentonite and water-soluble polyacrylamide-based polymers and a polysaccharide is used as a binder in the preparation of raw pellets from iron ore material, and the consumption of the components of this mixture is 4.54 kg / t and 0.001 - 0.3 wt.% respectively. Water soluble polymers are used in pelletizing as a dry powder or water-in-oil emulsion. Polymers include homopolymers, ternary and quarter copolymers, can be anionic, amphoteric or non-ionic. The use of water-soluble polymers according to the invention for the activation of bentonite leads to an increase in the iron content and a decrease in the silica content in the pellets, as well as to an improvement in the uniformity of the grain size distribution of the raw pellets. 7 hp f-ly.

Description

The invention relates to the agglomeration of iron ore materials and can be used in the manufacture of iron ore pellets.

The purpose of the invention is to improve the quality of raw granules.

A bicomponent-blend consisting of bentonite in an amount of up to $ C kg per 1 ton of iron ore material and water-soluble polymers based on polyacrylamide and is used as a binder in the preparation of raw pellets from iron ore material.

polysaccharide in the amount of 0.001 - 0.3 wt.% of the material. Polymers suitable for use in the present invention may include water soluble homopolymers, copolymers, ternary and quadruple copolymers. Suitable polymers may be anionic, amphoteric or non-ionic. In the invention, synthetic or naturally occurring polymers of high or low molecular weight may be used. characterized by their intrinsic viscosity. Other suitable polymers suitable for bonding iron ore particles,

JV JV About JV

U4

include polysaccharides from the group including carboxymethylcellulose, guar gum, hydroxyethylcellulose, and mixtures thereof.

Polymers suitable for use in the present invention must have a binding activity to the material particles and be able to be used in at least one of the application systems. The application systems are either a water in oil emulsion system or a dry powder system. Binding polymers suitable for use in the invention are particularly suitable if they have a high molecular weight.

,

. 75 t

Water-soluble polymers include, among others, polyacrylamide-based polymers and those polymers that polymerize by adding vinyl or acrylic monomers to a solution with a free radical. Typically, such polymers have ionic functional groups, such as a carboxyl group, a sulfamide group, or a quaternary anionium group. Suitable polymers can be derived from ethylenically unsaturated ionomers, including acrylamide, acrylic acid and methacrylamide. Alkali metal or ammonium salts may also be suitable.

The polymers preferably used in this invention have the following general formula:

ten

0

where R, R and K} independently of one another are hydrogen chloride or methyl, Rg is an alkali metal ion, such as Na or K, and R4 is one of the following radicals:

(O - OR5,

where Re is an alkyl group containing from k to 5 carbon atoms;

(2)

ABOUT

II

-S-O-Ib

where R6 is an alkyl group containing up to 8 carbon atoms;

(h) 9

-0-C-R7

where R7 is either methyl, or ethyl;

(k) phenyl;

(5) substituted phenyl;

(6) -CN or

(7)

 Ln

where a is equal to 5–90, preferably 30–60%, b is preferably 30–60%, c is 0.1–20% under the condition that a + b + c is 100%, and d is a positive integer of 1000–500000.

In some cases, the alkoxy or acyloxy groups in the polymer may be partially hydrolyzed to the corresponding alcohol group to form a quad copolymer of the following general formula:

B

-OVG- R

where K, R, Kg, a, b and d

above, a d is -OR

or

identified

five

ABOUT

II

-O-C-RV

where Kg and RT are defined above, c is 0.2–20%, and e is between 0.1–20%.

Preferred copolymers have the following formula:

where Ra + is an alkali metal ion, such as Na or K, f is 5 to 90, preferably 30-60%, g is 5-90, preferably 30-60%, provided that f + g

where R, R, R. ,, R7, f, g, h, d and e are defined above.

Other water soluble polymers suitable for use in this invention include polymers prepared by homopolymerization and copolymerization with regular alternation of units of the following water soluble monomers: acrylic and methacrylic acids; salts of acrylic and metacryloic acids of the following formula:

Re9

II

CH-fC-C-O-Rs

 where Rg is a hydrogen atom or methyl, and R represents a hydrogen atom, an alkali metal atom (la, e.g., sodium, potassium), an ammonium group, an organoammonium group of the formula | RW | iRj lR, ttlNH + lf where Rw, R ", Riu independently of one another represent a hydrogen atom or an alkyl group having 1-18 carbon atoms (this may be necessary to reduce the length and number of

equal to 100%, a d is an integer positive number and equal to 1000-500000.

Preferred terpolymers have the following formula:

ten

where RЈ is Na or K, RT is methyl, ethyl or butyl and f is 5-90, preferably 30-60%, g is 5-90, preferably 30-60%, h is 0.2-20% , provided that f + g + h is 100%, ad is defined above.

Preferred quaternary copolymers have the following formula:

in long chain alkyl groups to achieve water solubility of the monomer, e.g. 1-3 carbon atoms), an aryl group such as a benzyl group, or a hydroxyalkyl group having 1-3 carbon atoms such as triethanolamine, or mixtures thereof; acrylamide and methacrylamide and their production -. including acrylamide and methacrylamide monomers of the following formula:

H

m / k them,

 Rtt

where RO is a hydrogen atom or a methyl group; where Ry $ is a hydrogen atom by a methyl group or an ethyl group; wherein it is a hydrogen atom, a methyl group, an ethyl group or -K (where R / 6 is a divalent alkylene, phenylene or cycloalkylene hydrocarbon group having 1-13 carbon atoms, preferably an alkylene group,

715565W

having 2-8 carbon atoms, cycloalkylene group, having 6-8 carbon atoms or phenylene group, most preferably:

5 gd

) g-CH (2, i

—CH (SNE),

X is a monovalent cation, such as a hydrogen atom, an alkali metal atom (e.g., sodium or potassium), an ammonium group by an organoammonium group of the formula (i7 / R j | / Rj $ / NH +, where RI,, Rfe independently represent a hydrogen atom, an alkyl group having 1-18 carbon atoms (it may be necessary to reduce the number and length of long-chain alkyl groups in order to achieve water solubility of the monomer, for example, 1-3 carbon atoms), an aryl group, such as a phenyl or benzyl group, or an oxy group having 1-3 carbon atoms, such as triethanolamine, or mixtures thereof: etc. Specific examples of water-soluble monomers that can be homopolymerized or copolymerized and suitable for use in the process of the present invention are acrylamide and acrylamide and methacrylamide sulfonic acids and sulfonates, such as 2-acrylamido-2-methylpropanesulfonic acid (referred to as AMPS), AMPS sodium salt, AMPS ammonium salt, AMPS organoammonium salt. These polymers can serve as effective binding agents for mineral ore concentrates at approximately the same concentrations or binding quantities as polymeric acrylamide-based polymeric binders.

These water-soluble monomers can be copolymerized with a smaller amount (for example, less than an approximate 20 mol.%, Preferably less than about 10 mol.% Of the total monomers reacted) of one or more hydrophobic vinyl monomers. For example, with vinyl monomers of the formula

R)

5 where RgЈ is a hydrogen atom or

methyl fight

as a group

halogen atom (for example, chlorine)

r; -o-RtfC

2V

or

- С - 0 - RZ $, where O,

R2b

is alkyl0

5 5.,

0

which group, aryl group or arylalkyl group having 1-18 carbon atoms, where R is an alkyl group having 1-8 carbon atoms, R23 is an alkyl group having 1-6 carbon atoms, preferably 2-4 carbon atoms represents a hydrogen atom, a methyl group, an ethyl group or a halogen atom (e.g., chlorine), preferably a hydrogen atom or a methyl group, provided that the RUO is preferably a hydrogen atom if it is an alkyl group. Specific examples of suitable sopolimerizue- Mykh hydrophobic vinyl monomers are alkyl esters of acrylic and methacrylic acids such as methyl acrylate, methyl methacrylate, etilkrilat, ethyl methacrylate, butyl acrylate, isobutyl tilakrilat, dodecyl acrylate, 2-ethyl hexyl acrylate, etc. vinyl ethers, such as vinyl acetate, vinyl propionate, vinyl butyrate, etc., vinyl benzenes, such as styrene, alpha methyl styrene, vinyl toluene, vinyl ethers, such as propyl vinyl ether, butyl vinyl ether, butyl vinyl ether, and vinyl chloride, and vinyl chloride; meth ilvinyl ether, ethylvinyl ether, etc .; vinyl halides such as vinyl chloride, vinylidene chloride, etc., etc.

Preferred water-soluble monomers of these. Water-soluble polymers are acrylamide, AMPS and AMPS sodium salt, sodium acrylate 5 and ammonium acrylate. Preferred hydrophobic monomers are with acetate, ethyl acrylate, styrene and methyl methacrylate.

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the proposed isobluchayut any convenient

use of an emulsion when it comes to obtaining that the amount to concentrate is degraded by water, the required polymers from water leads to the firing of the granules. Cro10

ce cy

that with the dy an sm see gl o dv u well sm sm le ko but by the time

Moreover, the hydrophobic liquid or oil in the inverted system emulsion of water in oil is consumed during roasting. Burning out oil droplets from the internal zones of the granules increases the porosity of the granules. This increase in porosity is believed to improve the removal of water vapor from the granules and reduce the likelihood of thermal shock during the firing of the granules.

Another advantage achieved by using a water-in-oil emulsion system to add a polymeric binder to the iron ore concentrate during pelletization is to reduce the contact time required for sufficient mixing of the polymeric binder with the iron ore concentrate. Only contact time after emulsion spraying of the polymer with an iron ore concentrate is sufficient, which is sufficient to activate the polymer on the surface of the iron ore concentrate. The duration may vary depending on the emulsion system used and the concentration of the polymer binder in the emulsion system, as well as on the total amount of polymer binder splashed on the iron ore concentrate. In suitable embodiments of the invention, sufficient time to penetrate the polymeric binder system into the iron ore concentrate is achieved by spraying the emulsion with water in the iron ore concentrate, where immediately after this the concentrate is fed to the granulation drum.

} Applying an emulsion of water in oil to the iron ore concentrate to be processed can be carried out by applying the emulsion to the iron ore concentrate using any conventional spray equipment. Bentonite is scattered from a vibrating hopper or other dispersing agent, at the end

1i

ten

20

25

35

Jq. ds 0

five

the iron ore centrate and this composition are conveyed to the granulation drum by a conveyor.

The invention also includes applying polymer binder systems to iron ore concentrate in the form of dry powders. In these embodiments, dry powdered polymers are mixed together with powdered clay or added separately. The powder composition is scattered on the iron ore concentrate as the concentrate moves on the conveyor in the direction of the granulating drum. The vibrations of the conveyor devices and the action of the granulating drum mix the powders with the iron ore concentrate. After a sufficient time: contact with moisture from the iron ore concentrate, the polymers adsorb to the concentrate surface. A suitable contact time may be almost instantaneous, but is often from about 1 minute to 3 hours or more. Further mixing occurs with stirring in the granulating drum. An embodiment of the present invention using a dry polymer powder eliminates the need for using equipment to spray an emulsion.

The use of the proposed method leads to an increase in the quality of the obtained pellets: an increase in the iron content and a decrease in the silicon dioxide content in the pellets, an increase in the strength of the raw pellets and an improvement in the uniformity of their particle size distribution.

Claims (2)

Invention Formula 1. A method of pelletizing iron ore material for agglomeration, comprising mixing this material with a two-component binder, consisting of bentonite and water-soluble polyacrylamide-based polymers and polysaccharide, pelletizing the mixture to produce raw granules and strengthening them, such as the strengthening firing, characterized in that improving the quality of raw granules; polymers in the amount of 0.001 - 0.3 wt.% of iron ore material are applied to the material in the form of a dry powder or in the form of a water-in-oil emulsion, while the consumption of bentonite P15565M up to k, kg per ton of iron ore material. R, R | IR j is hydrogen or methyl; K - alkali metal ion - 15 la (Na + or K); R4 bind of the following radicals: -ORjj, where an alkyl group having up to 5 is -20 mo of carbon; I -C-0-R, R is an alkyl group having l Where R40 II - OR 5. or -O-C-RV from 0.2-20%, and e 0.1-20%. o The method according to claim 2, wherein the polymers consist of acrylamide monomer units, sodium acrylate, vinyl acetate, and mixtures thereof. 5. A method according to claim 1, characterized in that the polymers consist of monomer units of acrylamide DA and meta krilamide and their derivatives of the formula S 12 2. The method according to claim. Characterized in that the polymers have the general formula where K-, - methyl or butyl, phenyl, substituted phenyl, -CN or a 5-90, preferably 30-60%; b is preferably 30-60%,. from 0.1 to 20%, provided that a + b + from 100%, a d is an integer equal to 1000-500000. where VOD ° P ° D or methyl group; hydrogen, methyl or ethyl group; hydrogen, methyl, ethyl group or -K (L-UO, X, where R # is a bivalent hydrocarbon group having 1-13 carbon atoms, and X is a monovalent cation. 6. The method according to claim 1, wherein the polymers are polysaccharide polymers. 7. The method according to claim 6, wherein the polysaccharide polymers are selected from the group consisting of carboxymethylcellulose, guar gum, hydroxyethylcellulose, and mixtures thereof. ) 315565 14 8. The way pop. 1, I distinguish - Priority points: u and with the fact that as iron-21 O1; 85 o p ore material use takoni-09. o9. 85 on PP. 2-8. tovoy ore.