CN104384020B - A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique - Google Patents

A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique Download PDF

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CN104384020B
CN104384020B CN201410613983.6A CN201410613983A CN104384020B CN 104384020 B CN104384020 B CN 104384020B CN 201410613983 A CN201410613983 A CN 201410613983A CN 104384020 B CN104384020 B CN 104384020B
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dry
ore
stone
mine tailing
ultra
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CN104384020A (en
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姜磊
孟如奔
费腾
王小宇
李晓燕
王超
毛瀚波
李桂琴
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North Heavy Industry Group Co Ltd
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North Heavy Industry Group Co Ltd
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Abstract

A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique being applied in Ultra-low-grade magnetite stone technical field of beneficiation, described technique specifically comprise the following steps that Ultra-low-grade magnetite stone is adopted gyratory crusher and gyratory crusher carry out coarse crushing and in broken after, carry out the dry throwing preliminary election of one section of magnetic pulley, mine tailing stone enters two-stage nitration dry throwing magnetic pulley, and refined ore enters hammer mill and carries out operation in small, broken bits;Product in small, broken bits is through screening, and refined ore backs into operation in small, broken bits, and mine tailing stone enters screening, can as sandstone aggregate product;Dry separation concentrate adopts grinding of ball grinder Ore, and through one roughing, twice selected, obtains dry refined ore after once concentration and once filtration;Mill selects the concentrated machine concentration of mine tailing, after filter filters, with dry-dressing machine mine tailing in the lump dry heap.Armco magnetic iron content is the Ultra-low-grade magnetite of about 5% by this invention, and the dry screened aggregate product depth that is used as of mine tailing of throwing crushes, and reduces into mill amount, saves beneficiation cost so that economic benefit is significantly improved.

Description

A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique
Technical field
The present invention relates to a kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique in Ultra-low-grade magnetite stone technical field of beneficiation.
Background technology
Iron ore is the most important basic material of steel and iron industry.Along with the fast development of national economy, the demand of iron ore resource is sharply strengthened by China.The iron ore of domestic easy choosing reduces day by day simultaneously, announces according to Ministry of Land and Resources, and within 2010, iron ore deposit reserves 726.99 hundred million tons are found out in the whole nation, wherein: reserves 7,900,000,000 tons, basic unit price 222.32 hundred million tons, stock number 504.67 hundred million tons, major part is lean ore, and rich ore only has 9.27 hundred million tons, accounts for 1.2%.Develop domestic Ultra-low-grade magnetite and become the effective ways solving domestic iron ore concentrate breach.At present, the problem that in the ore dressing process of Ultra-low-grade magnetite stone, ubiquity has 3 points: 1, process raw ore amount big.Owing to raw ore Armco magnetic iron grade is low, therefore ratio of concentration is high, causes that the day output of Ultra-low-grade magnetite is substantially more than ton;2, Iron concentrate yield is few.Because ratio of concentration is low, causing that the product yield of Ultra-low-grade magnetite mineral processing production line is few, this also makes the economic benefit of Ultra-low-grade magnetite mineral processing production line can not be guaranteed;3, the mine tailing amount produced in producing is very big.And tailings glass gets up highly difficult.Comprehensive above 3 common reasons, cause Ultra-low-grade magnetite beneficiation cost high and environmental pollution is big, and economic benefit is difficult to improve.Therefore, the beneficiation method developing a kind of Ultra-low-grade magnetite stone high-efficiency environment friendly is extremely urgent.The depth crushing ore-dressing technique of this method introduction provides effective method for solving this problem.
Summary of the invention
It is an object of the invention to provide a kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique, to solve in Ultra-low-grade magnetite stone ore-dressing technique, raw ore ore grinding treating capacity is big, the a large amount of mine tailing stone processing costs produced are high, the problem that ore dressing economic benefit is low, it is achieved Ultra-low-grade magnetite stone comprehensively utilizes, Ultra-low-grade magnetite stone is through depth crushing, dry throwing preliminary election, obtains qualified concentrate containing stone, improves ore dressing stone benefit in advance.
The object of the present invention is achieved like this: a kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique, described technique specifically comprises the following steps that
(1) Ultra-low-grade magnetite stone is adopted gyratory crusher and gyratory crusher carry out coarse crushing and in broken after, carry out that one section of magnetic pulley is dry throws preliminary election, mine tailing stone enters that two-stage nitration is dry throws magnetic pulley, and refined ore enters hammer mill and carries out operation in small, broken bits;
(2) product in small, broken bits is through screening, > 3mm enters two-stage nitration magnetic pulley dry separation in the lump with one section of preliminary rejection stone, refined ore backs into operation in small, broken bits, mine tailing stone enters screening, granularity is divided into tetra-grades of 0-5mm, 5-10mm, 10-26.5mm, > 26.5mm, can as sandstone aggregate product;< 3mm Ore enters dry-dressing machine dry separation, energy jettisoning 70% mine tailing, greatly reduces ore grinding treating capacity;
(3) dry separation concentrate adopts grinding of ball grinder Ore, and being milled to fineness is that-200 orders account for the breeze of 80% and make ore pulp, and through one roughing, twice selected, obtains dry refined ore after once concentration and once filtration;
(4) mill selects the concentrated machine concentration of mine tailing, after filter filters, with dry-dressing machine mine tailing in the lump dry heap;
The concentrate of dry throwing preliminary election is sent in hammer mill by described step (1), and the product feeding vibrosieve of hammer mill is sieved by step (2), Ore less than 3mm is sent into dry-dressing machine, will be greater than the Ore of 3mm through two-stage nitration magnetic pulley is dry throw preliminary election after, then concentrate returned to hammer mill carry out operation in small, broken bits.
The present invention is characterized by its structure and working principle.Its operation principle is, for Armco magnetic iron content about 5% Ultra-low-grade magnetite Ore, raw ore is carried out depth crushing, through selecting the dry throwing of stage crushing stage, the dry screened aggregate product depth that is used as of mine tailing of throwing crushes, < 3mm is through the dry throwing of dry-dressing machine, the lower mineral of sieve enter back into mill choosing, obtain concentrate, shattering process carries out multistage dry throwing preliminary election in advance, by part dry separation mine tailing by grading, it is used as crushed stone aggregate to sell, greatly reduce into mill amount, save beneficiation cost, obtain the Ultra-low-grade magnetite Comprehensive recycle technology of two kinds of products, economic benefit is made to obtain significant raising.This ore-dressing technique adopts the comprehensive utilization process flow process of " the dry throwing mine tailing classification of stage crushing stage is done the dry concentrate of throwing of aggregate and selected to obtain iron ore concentrate through mill ".The indices of product is qualified, and obtains two kinds of products.
A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique is compared with prior art, having Armco magnetic iron content is the Ultra-low-grade magnetite of about 5%, through selecting the dry throwing of stage crushing stage, the dry screened aggregate product depth that is used as of mine tailing of throwing crushes, < 3mm is through the dry throwing of dry-dressing machine, it is substantially reduced into mill amount, save beneficiation cost, realize Ultra-low-grade magnetite comprehensive reutilization to greatest extent, make the advantages such as economic benefit is significantly improved, will be widely used in Ultra-low-grade magnetite stone technical field of beneficiation.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention is described in detail.
Fig. 1 is the process chart of the present invention.
Detailed description of the invention
With reference to accompanying drawing, a kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique, described technique specifically comprises the following steps that
(1) Ultra-low-grade magnetite stone is adopted gyratory crusher and gyratory crusher carry out coarse crushing and in broken after, carry out that one section of magnetic pulley is dry throws preliminary election, mine tailing stone enters that two-stage nitration is dry throws magnetic pulley, and refined ore enters hammer mill and carries out operation in small, broken bits;
(2) product in small, broken bits is through screening, > 3mm enters two-stage nitration magnetic pulley dry separation in the lump with one section of preliminary rejection stone, refined ore backs into operation in small, broken bits, mine tailing stone enters screening, granularity is divided into tetra-grades of 0-5mm, 5-10mm, 10-26.5mm, > 26.5mm, can as sandstone aggregate product;< 3mm Ore enters dry-dressing machine dry separation, energy jettisoning 70% mine tailing, greatly reduces ore grinding treating capacity;
(3) dry separation concentrate adopts grinding of ball grinder Ore, and being milled to fineness is that-200 orders account for the breeze of 80% and make ore pulp, and through one roughing, twice selected, obtains dry refined ore after once concentration and once filtration;
(4) mill selects the concentrated machine concentration of mine tailing, after filter filters, with dry-dressing machine mine tailing in the lump dry heap;
The concentrate of dry throwing preliminary election is sent in hammer mill by described step (1), and the product feeding vibrosieve of hammer mill is sieved by step (2), Ore less than 3mm is sent into dry-dressing machine, will be greater than the Ore of 3mm through two-stage nitration magnetic pulley is dry throw preliminary election after, then concentrate returned to hammer mill carry out operation in small, broken bits.
Embodiment one
1, adopt PXZ-1417 gyratory crusher and PYT-B2235 gyratory crusher to crush in above-mentioned Ore, carry out preliminary election with two sections of CT-1014 type magnetic druies afterwards.Pre-concentrate selection feeds 8 PC-M1825 hammer mills and carries out operation in small, broken bits.
2, product in small, broken bits is through screening, and > 3mm enters two-stage nitration magnetic pulley dry separation in the lump with one section of pre-separation using magnetic pulley mine tailing, and concentrate returns operation in small, broken bits.Mine tailing stone enters screening, and granularity is divided into tetra-grades of 0-5mm, 5-10mm, 10-26.5mm, > 26.5mm, can as sandstone aggregate product.The Ore of < 3mm enters CTG-1030 dry-dressing machine dry separation, and the mine tailing of jettisoning about 70% effectively reduces ore grinding amount;
3, dry separation concentrate feeds MQG3660 ball mill, ore milling product enters one roughing magnetic separator, mine tailing enters Tailings System, concentrate is squeezed into cyclone by pump, dusting cover is entered in cyclone overflow, entering MC3660 two-stage nitration ball mill in the lump after oversize and the concentrated magnetic separator concentrating of cyclone underflow, ball mill product enters back into secondary magnetic rougher, and concentrate is returned cyclone by pump again.Product under dusting cover sieve enters a selected magnetic separator, and concentrate enters selected two magnetic separators, and final concentrate is sent to concentrate stockyard by belt after disk filter filters.
4, mill selects comprehensive mine tailing to concentrate through NZY-45 type thickener, after XPG-200 filter filters, with dry-dressing machine mine tailing in the lump dry heap.
Obviously, the above-mentioned implementation example of the present invention is only for clearly demonstrating example of the present invention, and is not the restriction to embodiments of the present invention.For affiliated those of ordinary skill in the related art, other multi-form change and variation can also be made on the basis of the above description.Here all of implementation cannot be illustrated.Every belong to apparent change that technical scheme amplified out or the row still in protection scope of the present invention.

Claims (2)

1. a Ultra-low-grade magnetite stone depth crushing ore-dressing technique, it is characterised in that: described technique specifically comprises the following steps that
(1) Ultra-low-grade magnetite stone is adopted gyratory crusher and gyratory crusher carry out coarse crushing and in broken after, carry out that one section of magnetic pulley is dry throws preliminary election, mine tailing stone enters two-stage nitration magnetic pulley dry separation, and refined ore enters hammer mill and carries out operation in small, broken bits;
(2) product in small, broken bits is through screening, throw preliminary rejection stone dry with one section of magnetic pulley more than 3mm enters two-stage nitration magnetic pulley dry separation in the lump, two-stage nitration magnetic pulley dry separation refined ore backs into operation in small, broken bits, two-stage nitration magnetic pulley dry separation mine tailing stone enters screening, granularity is divided into 0-5mm, 5-10mm, 10-26.5mm, more than tetra-grades of 26.5mm, can as sandstone aggregate product;Enter dry-dressing machine dry separation, energy jettisoning 70% mine tailing stone less than 3mm Ore, greatly reduce ore grinding treating capacity;
(3) dry-dressing machine dry separation refined ore adopt grinding of ball grinder Ore, being milled to fineness is that-200 orders account for the breeze of 80% and make ore pulp, roughly selects for one section, one section of classification and once screening after, fine fraction product through twice selected and once filtration after obtain dry refined ore;The concentrated magnetic separation of coarse fraction product, secondary grinding, after two-stage nitration is roughly selected, return one section of graded operation;
(4) in above-mentioned steps (3), all concentrated machines of mine tailing stone that sort concentrate, and after disk filter filters, the mine tailing stone obtained and dry-dressing machine dry separation mine tailing stone is dry heap in the lump.
2. a kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique described in claim 1, it is characterized in that: one section of magnetic pulley is done the refined ore throwing preliminary election by described step (1) and sends in hammer mill, and product feeding vibrosieve in small, broken bits is sieved by step (2), Ore less than 3mm is sent into dry-dressing machine, will be greater than the Ore of 3mm after two-stage nitration magnetic pulley dry separation, then two-stage nitration magnetic pulley dry separation refined ore is returned to hammer mill carry out operation in small, broken bits.
CN201410613983.6A 2014-11-05 2014-11-05 A kind of Ultra-low-grade magnetite stone depth crushing ore-dressing technique Expired - Fee Related CN104384020B (en)

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CN105032597B (en) * 2015-05-13 2017-11-24 河源旗滨硅业有限公司 Multipass sort sand machining production line
CN105498949B (en) * 2016-01-05 2018-04-24 马钢(集团)控股有限公司 A kind of Ultralean magnetite picks up integration pre-selection technique and device
CN105944824B (en) * 2016-05-20 2018-08-31 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of weak-magnetic iron ore dry classification pre-selection technique
CN107309080A (en) * 2017-06-08 2017-11-03 陕西冶金设计研究院有限公司 A kind of super low-grade primary magnetic iron ore comprehensive development and utilization method
CN109482338A (en) * 2018-12-21 2019-03-19 马钢集团矿业有限公司 A kind of beneficiation method of the narrow gradation of magnetic iron ore, the independent ore grinding of chats
CN109746104A (en) * 2019-02-11 2019-05-14 鞍钢集团矿业有限公司 A kind of magnetic iron ore is broken-pre-selection-grinding process
CN112295722A (en) * 2020-08-18 2021-02-02 安徽金安矿业有限公司 Differentiated production method of high-quality magnetite concentrate

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