CN103521363B

CN103521363B - Low-grade bauxite raw ore open-circuit grinding ore-dressing technique

Info

Publication number: CN103521363B
Application number: CN201310493373.2A
Authority: CN
Inventors: 李耀吾
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-10-19
Filing date: 2013-10-19
Publication date: 2016-06-22
Anticipated expiration: 2033-10-19
Also published as: CN103521363A

Abstract

The invention provides a kind of low-grade bauxite raw ore open-circuit grinding ore-dressing technique。To roughly select, scan, selected, obtain A/S5.5～6 concentrate, the underflow of classified machine discharge or sand return, its A/S reaches medium grade alumyte standard, ore grain size 60 order feeds after another grinding machine ore grinding again through grader classification, 200 orders are accounted for 95% overflow carry out roughly selecting, scan, selected, obtain A/S8～11 concentrate。In this process makes full use low-grade bauxite, the difference of diaspore, kaolinite Mohs' hardness, brings up to more than 8 by bauxite concentrate A/S, can improve alumina producing Al₂O₃The response rate is high, energy-conservation, cost is low, alkaline consumption is low, not only Mineral Processing Enterprises can be increased production, energy-conservation, reduce cost, high-quality, favorable rates, produce great economic benefit, it can be additionally used in the production of high-alumina clay Mineral Processing Enterprises, can also be used for the ore dressing of medium grade alumyte, its concentrate A/S can stably 11～12。

Description

Low-grade bauxite raw ore open-circuit grinding ore-dressing technique

Technical field

The invention belongs to technical field of beneficiation, particularly to a kind of low-grade bauxite raw ore open-circuit grinding ore-dressing technique。

Background technology

In bauxite, the granularity containing useful, toxic mineral crystallization is very thin, diaspore at 5～10 microns, high stone grain size number only 5 microns。Require during ore dressing that by tcrude ore granularity of supply ore dressing grinding machine after broken, in small, broken bits be about 20mm。Bauxite Milling by raw ore ore grinding to fineness 200 order (0.074mm), must reach 95～98% and be advisable, and all adopts closed circuit mode ore grinding for this each Mineral Processing Enterprises ore grinding。

Closed circuit mode ore grinding, is go to realize by the grader in grinding system, has employing cyclone classification machine or spiral classifier。When adopting cyclone classification machine, its overflow requires that 200 orders reach about 98%, send flotation column to carry out roughly selecting, scans, selected, and underflow returns grinding machine and refaces；When adopting spiral classifier, its overflow requires that 200 orders are 92～95%, send mechanical stirring flotation machine to carry out flotation, and sand return then returns raw ore grinding machine and refaces formation closed circuit grinding。

Currently, the greatest problem of use closed circuit grinding technique is: do not consider main beneficial mineral diaspore (Al in bauxite₂O₃·H₂O) Mohs' hardness 6～7, main toxic mineral kaolinite (Al₂O₃·2SiO₂·2H₂O) difference of Mohs' hardness 1～3, particularly relate to the greatest differences of grindability in grinding machine, namely kaolinite easily grinds, diaspore difficulty is ground, in addition raw ore feed preparation unit size is 20mm, and the fineness of cyclone classification machine underflow or spiral classifier sand return is below 60 orders, and both granularity difference are big, it is overground that closed circuit grinding easily causes kaolinite, diaspore, even crossing and be ground to below 400 orders, in its ore pulp, 400 orders account for 70～80%, cause production operation and index unstable。And because concentrate, mine tailing are meticulous, sedimentation velocity is slow, and pressure filter efficiency is low。When adopting cyclone classification machine classification, its closed circuit grinding circulation ore deposit amount is 4 times of hour production capacity, and spiral classifier closed circuit grinding circulation ore deposit amount is 2.6 times of hour production capacity。Accordingly, if changing open-circuit grinding into, raw ore volume of ore mill has a more substantial increase。

Described low-grade bauxite ore dressing, the two kinds of graders being respectively adopted, the detection of each grade mog of its closed circuit grinding system and chemical analysis, it is common to there is problems in that

First grader send flotation circuit, its overflow about A/S2.6, far below grinding machine raw ore for ore deposit grade, fully prove that kaolinite easily grinds, diaspore difficulty is ground, it is many and cause to be that kaolinite enters the ratio of 200 order grades, and there is the underflow of cyclone classification machine or the feature higher for sand return A/S of spiral classifier。When adopting spiral classifier, volume of ore mill is 75t/h, raw ore A/S3.32, and its sand return concentration is 86.65%, through to the detection of each grade percentage composition of sand return and chemical analysis, being listed as follows:

If spiral classifier classification efficiency is controlled well, 400 order grades should be easily accessible spiral classifier overflow and enter former flotation flowsheet, now the above weighted average sand return A of 400 orders relatively coarse fraction₂O₃59.70%, SiO₂12.63%, A/S4.94。

When adopting cyclone classification machine, through its underflow is carried out long period detection, chemical analysis, when awarding grinding machine raw ore A/S3～3.5, overall each grade average out to 100 order (0.149mm), percentage composition about 53%, A/S4.5；100～200 order percentage compositions about 40%, A/S6～7；200～400 orders (0.037mm), percentage composition about 7%, A/S 3。

Summary of the invention

The purpose of the present invention, be in that in sum closed circuit grinding flow process exist problems, it is provided that a kind of raw ore grinding machine ore discharge classified machine overflow 200 order account for 98% or 200 order account for 95% low-grade bauxite raw ore open-circuit grinding ore-dressing technique。

The low-grade bauxite raw ore open-circuit grinding ore-dressing technique of the present invention, includes raw ore open-circuit grinding cyclone classification machine technique and raw ore open-circuit grinding spiral classifier technique。

The raw ore open-circuit grinding cyclone classification machine technique of the present invention, it is by A/S3～3.5 bauxite raw ore, cyclone classification machine classification is fed after ore grinding, 200 orders that cyclone classification machine is discharged account for 98% overflow undertaken roughly selecting by flotation column, scan, selected, obtaining A/S5.5～6 concentrate I, mine tailing A/S1.4～1.6 scanned are discarded。Through underflow A/S4.5～4.7 that cyclone classification machine separates, its ore grain size 60 order feeds after another grinding machine ore grinding again through cyclone classification machine classification, 200 orders are accounted for 95% overflow feed flotation column carry out roughly selecting, scan, selected, thus obtaining A/S8～10 high-grade concentrate II, mine tailing A/S1.1～1.3 scanned are discarded。

The raw ore open-circuit grinding spiral classifier technique of the present invention, it is by A/S3～3.5 bauxite raw ore, spiral classifier classification is fed after ore grinding, 200 orders that spiral classifier is discharged account for 95% overflow undertaken roughly selecting by mechanical stirring flotation machine, scan, selected 1, selected 2, obtaining A/S5.5～6 concentrate I, mine tailing A/S1.4～1.6 through scanning are discarded。Again through spiral classifier classification after the sand return A/S4.94 of spiral classifier discharge, granularity 60 order feed another grinding machine ore grinding, and 200 orders are accounted for 95% overflow carry out roughly selecting, scan, selected 1, selected 2, thus obtaining A/S8～11 high-grade concentrate II, mine tailing A/S1.1～1.3 scanned are discarded。

The low-grade bauxite raw ore open-circuit grinding ore-dressing technique of the present invention, makes full use of only 1～3 feature many with mineral content of kaolinite Mohs' hardness in low-grade bauxite, bauxite concentrate A/S is brought up to more than 8, can improve alumina producing Al₂O₃The response rate is high, energy-conservation, cost is low, alkaline consumption is low, has huge technical economic benefit；Not only Mineral Processing Enterprises can be increased production, energy-conservation, reduce cost, high-quality, favorable rates, produce great economic benefit, could be applicable to the production of high-alumina clay Mineral Processing Enterprises。Present invention may also apply to the ore dressing of medium grade alumyte, its concentrate A/S can stably 11～12。

Accompanying drawing explanation

Fig. 1, is the process chart of the raw ore open-circuit grinding cyclone classification machine of the present invention；

Fig. 2, be the present invention the process chart of raw ore open-circuit grinding spiral classifier。

Detailed description of the invention

Below in conjunction with above-mentioned attached Example, the low-grade bauxite raw ore open-circuit grinding ore-dressing technique detailed description of the invention of the present invention is further described。

The raw ore open-circuit grinding spiral classifier technique of the present invention, it is by A/S3～3.5 bauxite raw ore, spiral classifier classification is fed after ore grinding, 200 orders that spiral classifier is discharged account for 95% overflow undertaken roughly selecting by mechanical stirring flotation machine, scan, selected 1, selected 2, obtaining A/S5.5～6 concentrate I, mine tailing A/S1.4～1.6 scanned are discarded。Again through spiral classifier classification after the sand return A/S4.94 of spiral classifier discharge, granularity 60 order feed another grinding machine ore grinding, and 200 orders are accounted for 95% overflow carry out roughly selecting, scan, selected 1, selected 2, thus obtaining A/S8～11 high-grade concentrate II, mine tailing A/S1.1～1.3 scanned are discarded。

The low-grade bauxite raw ore open-circuit grinding ore-dressing technique of the present invention, by flotation, its raw ore A/S4.5～4.7, flotation concentrate A/S up to 8～10, concentrate Al₂O₃68～70%, SiO₂7～8%；Raw ore A/S4.94, concentrate A/S up to 11, concentrate Al₂O₃More than 70%, SiO₂Less than 7%。

Claims

1. a low-grade bauxite raw ore open-circuit grinding ore-dressing technique, includes raw ore open-circuit grinding cyclone classification machine technique and raw ore open-circuit grinding spiral classifier technique, it is characterised in that:

A, raw ore open-circuit grinding cyclone classification machine technique, it is by A/S3～3.5 bauxite raw ore, cyclone classification machine classification is fed after ore grinding, 200 order 98% overflows that cyclone classification machine is discharged are roughly selected by flotation column, scan, selected, obtain A/S5.5～6 concentrate I, mine tailing A/S1.4～1.6 scanned are discarded, through underflow A/S4.5～4.7 that cyclone classification machine is discharged, its ore grain size 60 order feeds after another grinding machine ore grinding again through cyclone classification machine classification, 200 order 95% overflows are fed flotation column roughly select, scan, selected, obtain A/S8～10 concentrate II, mine tailing A/S1.1～1.3 scanned are discarded,

B, raw ore open-circuit grinding spiral classifier technique, it is by A/S3～3.5 bauxite raw ore, spiral classifier classification is fed after ore grinding, 200 order 95% overflows that spiral classifier is discharged are roughly selected by mechanical stirring flotation machine, scan, selected 1, selected 2, obtain A/S5.5～6 concentrate I, mine tailing A/S1.4～1.6 scanned are discarded, through the sand return A/S4.94 that spiral classifier is discharged, granularity 60 order feeds after another grinding machine ore grinding again through spiral classifier classification, 200 orders are accounted for 95% overflow roughly select, scan, selected 1, selected 2, obtain A/S8～11 concentrate II, mine tailing A/S1.1～1.3 scanned are discarded。