CN1187134C - Dry-type graded concentration method for precious metal tenuousness grainy tailings - Google Patents

Abstract

The present invention relates to ore dressing technology for precious metal tailing, particularly to a dry classifying and enriching method for superfine particle tailing of precious metal. The present invention is characterized in that superfine particle tailing powder of precious metal passes through the first step of dry classification: a dry superfine precise classifying device is used for carrying out particle size structure classification to the superfine particle tailing powder of precious metal; the superfine particle tailing powder of precious metal is classified into n particle size segments; the content of targeted ore in the tailing powder of each particle size segment is tested and analyzed; the tailing powder of a particle size segment, which has a low content of the targeted ore, is discarded; then, the superfine particle tailing powder of precious metal passes through the second step of dry classification; the dry superfine precise classifying device is used likewise for separating and classifying the tailing powder of the enriching particle size segment according to the density difference; the tailing powder of each particle size segment is respectively divided into a coarse part and a fine part; coarse powder is the heavy precious metal of the targeted ore, and fine powder is light impurities of non-targeted ore; therefore, the enrichment of the superfine particle tailing powder of precious metal is realized. The present invention has the characteristics of high efficiency and good environment protecting performance.

Description

Precious metal microfine mine tailing dry classification enrichment method

Technical field

The present invention relates to multiple-purpose project field, mine, be specifically related to the non-ferro metals debris technique of preparing.

Background technology

Along with the sustainable and stable development of national economy, to the demand increase year by year of mineral resources, and mineral resources will carried the burden of the population and the environment of excess load as a kind of non-renewable natural resources.Therefore, fully, reasonably develop national mineral resources, not only will realize, the more important thing is that the level of comprehensive utilization by improving resource realizes by increasing resource exploitation quantity.There is more than 7650 in state-owned mine in China, more than 140,000 in non-state-owned mine, for a long time, the extensive mode of utilizing has caused the luxus consumption and the waste of mineral resources, on the other hand, the ore dressing discarded object, promptly the annual emissions of mine tailing reaches more than 300,000,000 tons, the mine tailing amount of storage surpasses 6,000,000,000 tons, forms so-called " artificial mineral deposit ".The mine tailing that these are arbitrarily stacked not only takies a large amount of soils, also the heavy damage surrounding enviroment and the ecological balance.Dual-pressure in the face of resource and environment, improve the rate of extraction and comprehensive recovery levels by technological innovation, being the feasible way that rationally utilizes nature mineral resources and improvement, develops these " artificial mineral deposit ", also is the technical guarantee of mining industry sustainable development and even social economy's sustainable development.

The precious metal mine tailing is made up of less than 400 purpose subparticles granularity usually, wherein comprises purpose ore deposit precious metal ore particle and non-purpose ore deposit impurity etc.The microfine mine tailing mainly is owing to the inevitable crushing phenomenon of crossing in the ore dressing process causes, the purpose ore deposit that comprises some in these microfine mine tailings, be because existing traditional beneficiation method of generally using comprises that methods such as gravity treatment, flotation can't sort out fine granular purpose ore deposit effectively.And at present the sorting technology of the microfine mine tailing of report be so-called " CHRS " patented technology and " protect right gravity concentrator " based on this, " protecting right spiral fashion so ore separators " and sorting units such as " protecting right gold tailings recovery machine ".The operation principle of this technology is: the microfine mine tailing is under the wet method condition, and the centrifugal sedimentation that produces by the centrifugal device sorting of isolating makes the mineral with difference of specific gravity be able to the sorting enrichment.The purpose ore deposit that this technology obtains is liquid-solid two-phase flow state, need be by smelting after concentrated and dry the processing, and the governing problem of secondary pollution may be brought in meeting generation waste water and the non-purpose of pulpous state ore deposit in these processes.

Summary of the invention

Because of the defective that wet processing produced, the object of the present invention is to provide a kind of efficient height, precious metal microfine mine tailing dry classification enrichment method that the feature of environmental protection is good at the enrichment of the irretrievable precious metal microfine mine tailing of existing traditional method for separating institute and the microfine mine tailing sorting technology developed recently.

To achieve these goals, the technical solution used in the present invention is: precious metal microfine mine tailing dry classification enrichment method, it is characterized in that precious metal microfine mine tailing powder, through first step dry classification: adopt dry type super fine precision grading plant that precious metal microfine mine tailing powder is carried out the classification of particle grade structure, be divided into n grade section, each grade section mine tailing powder is carried out purpose mineral content test analysis respectively, and the grade section mine tailing powder that the purpose mineral content is lower is given up; Again through the second step dry classification: adopt dry type super fine precision grading plant respectively the mine tailing powder with enrichment grade section to be carried out the density contrast sorting classifying equally, the mine tailing powder of each grade section all is divided into slightly, thin two parts, meal is heavier purpose ore deposit precious metal, fine powder then is lighter non-purpose ore deposit impurity, thereby realizes the enrichment of precious metal microfine mine tailing powder.

The present invention is by the special processes of " two step classifications ", first step dry classification: adopt dry type super fine precision grading plant, precious metal microfine mine tailing powder is carried out the classification of particle grade structure, make particle diameter be suitable for the second step dry type density contrast sorting classifying, and the grade section mine tailing powder that the purpose mineral content is lower is given up; Again through the second step dry classification: each grade section mine tailing powder that the purpose mineral content is higher, the same dry type super fine precision grading plant that passes through is pressed the density contrast sorting classifying, obtain thick, thin two parts powder, fine powder (non-purpose ore deposit) is given up, meal is the purpose ore deposit precious metal of enrichment, realizes precious metal microfine mine tailing dry classification enrichment purpose.

The present invention compares with existing sorting mineral enrichment method, has the following advantages:

One by the present invention, can be applied to traditional ore-dressing practice with the high-performance dry type super fine precision grading plant in the modern powder process technology, realize traditional method for separating the enrichment of irretrievable precious metal microfine mine tailing.

They are two years old, the present invention has effectively utilized that dry type super fine precision grading plant reached at present: 4 tons/hour of classification treating capacities, cut diameter 2 microns percent of pass 95%, Newton classification efficiency are greater than performance indications such as 78%, not only treating capacity is big, flow process is compact to make the dry classification process of enriching, and efficiency of separation height, greater than 78% o'clock, the content in purpose ore deposit can reach 0.78 after " two step classifications " in theory as Newton (newton) classification efficiency ²* 100%, promptly 60.84%.

Its three, gained purpose ore deposit of the present invention and non-purpose ore deposit are the powder shaped material, the pasty material of more traditional method for separating gained the be more convenient for smelting in purpose ore deposit and the processing of dissolving in non-purpose ore deposit; Prevent secondary pollution, have favorable environment protection.

Its four, the present invention utilizes dry type super fine precision grading plant by the special processes of " two step classification ", carries out the enrichment of precious metal microfine mine tailing and handles, and can improve the rate of extraction and the comprehensive recovery levels of mineral resources.

Description of drawings

Fig. 1 is a process chart of the present invention

The specific embodiment

The present invention specifically implements in the following manner:

(1) precious metal microfine mine tailing is carried out preliminary treatment: drying was handled after the mine tailing with magnetic (or weak magnetic) material was carried out magnetic concentration, and non-magnetic mine tailing directly carries out drying to be handled, and obtains the mine tailing powder of moisture content≤2%; The mine tailing powder is carried out testing graininess, draw particle size distribution range: d _Max～d _Min

(2) dried mine tailing powder is carried out first step dry classification, adopt dry type super fine precision grading plant that precious metal microfine mine tailing powder is carried out the classification of particle grade structure, be divided into n grade section, the grade structure meets purpose ore deposit and non-purpose ore deposit particle constant speed sedimentation sorting principle, is specially:

The 1st grade section particle size range: $d_{\max }~d_{\max }\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}};$

The 2nd grade section particle size range: $d_{\max }\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^2;$

The 3rd grade section particle size range: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^2~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^3;$

The 4th grade section particle size range: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^3~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^4;$

N grade section particle size range: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{n-1}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^n$

In the formula: d _MaxMaximum particle diameter for the mine tailing powder;

ρ _MDBe purpose ore deposit grain density;

ρ _FMDFor non-purpose ore deposit grain density, when non-purpose ore deposit was multiple material, getting wherein, the material of density maximum was non-

The purpose mineral density.(precious metal acinous mine tailing has ρ usually _MD＞ρ _FMD)

The quantity of grade section is taken in theory: when $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^n$ Level off to the minimum grain size d of mine tailing powder _MinThe time the n value, can be taken to for reducing the classification hop count in the actual classification: when $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^n$ The mine tailing powder that the levels off to sieve n value when cumulative percentage is 10% pairing particle diameter down.

Institute's employing grading plant requires its Newton classification efficiency 〉=78%, and the cut diameter precision can reach sieve cumulative percentage 〉=95% down, and the cut diameter value is adjustable continuously.

(3) to each the grade section mine tailing powder behind first step dry classification, carry out purpose mineral content test analysis respectively, the grade section mine tailing powder that the purpose mineral content is lower is given up (value according to precious metal is judged), and each enrichment grade section mine tailing powder that the purpose mineral content is higher carries out the second step dry classification.

(4) second step dry classifications adopt dry type super fine precision grading plant equally, respectively each higher enrichment grade section mine tailing powder of purpose mineral content are carried out the density contrast sorting classifying, the cut diameter d of each grade section during classification ₉₅(sieve down cumulative percentage be 95% pairing particle diameter) is taken as the minimum grain size of this section, as n grade section particle size range: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{n-1}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^n,$ Then the cut diameter of this grade section promptly is taken as $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^n.$

(5) behind the second step dry classification, the mine tailing powder of each grade section all by dry type super fine precision grading plant be divided into slightly, two parts carefully, wherein, meal is heavier purpose ore deposit precious metal, fine powder then is lighter non-purpose ore deposit impurity.

Claims (2)

1. The dry classification and enrichment method of precious metal fine tailings is characterized in that the precious metal fine tailings powder is subjected to dry classification in the first step: a dry ultrafine precision classification device is used to fine the precious metal fine tailings The ore powder is classified by particle size structure, divided into n particle size segments, and the tailings powder of each size range is tested and analyzed for the target ore content, and the tailings powder of the size range with a lower target ore content is discarded; After the second step of dry classification: the dry ultra-fine precision classification device is also used to carry out density differential separation and classification on the tailings powder with enriched particle size sections, and the tailings powder in each particle size section is separated. It is divided into coarse and fine parts, the coarse powder is the heavier target ore precious metal, and the fine powder is the lighter non-target ore impurities, so as to realize the enrichment of precious metal fine tailings powder. 2. The method for dry classification and enrichment of precious metal fine tailings according to claim 1, characterized in that its specific implementation method is as follows: (1) Pretreatment of precious metal fine-grained tailings: carry out magnetic separation and enrichment on tailings with magnetic or weak magnetic substances and then dry them, and dry them directly to obtain tailings with a moisture content of ≤2%. Tailings powder; the tailings powder is tested for particle size, and the particle size distribution range is obtained: d _max ~ d _min ; (2) Carry out the first step of dry classification on the dried tailings powder, and the particle size structure conforms to the principle of constant velocity sedimentation and separation of target ore and non-target ore particles, specifically: Particle size range of the first particle stage: $d_{\max }~d_{\max }\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}};$ Particle size range of the second particle stage: $d_{\max }\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^2;$ Particle size range of the third particle stage: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^2~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^3;$ Particle size range of the fourth particle stage: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^3~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^4;$ ......... Particle size range of the nth particle stage: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}-1}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}}$ In the formula: d _max is the maximum particle size of tailings powder; _ρMD is the particle density of the target ore; ρ _FMD is the particle density of the non-purpose ore, when the non-purpose ore is a variety of substances, the material with the highest density is taken as the non-purpose ore Target ore density; The number of particle fractions is theoretically taken to: when $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}}$ The n value when approaching the minimum particle size d _min of the tailings powder can be taken to reduce the number of classification stages in actual classification: when $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}}$ The n value when approaching the particle size corresponding to the cumulative percentage under the tailings powder sieve of 10%; The dry-type ultra-fine precision grading device used requires its Newton classification efficiency to be ≥ 78%, the precision of the cut particle size to reach the cumulative percentage under the sieve ≥ 95%, and the value of the cut particle size to be continuously adjustable; (3) In the second step of dry classification, the split particle diameter d ₉₅ of each particle size section is taken as the minimum particle size of the section, such as the particle size range of the nth particle size section: $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}-1}~d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}},$ Then the split particle size of the particle size segment is taken as $d_{\max }{\left(\sqrt{\frac{{\mathrm{\ρ}}_{\mathrm{FMD}}}{{\mathrm{\ρ}}_{\mathrm{MD}}}}\right)}^{\mathrm{no}},$ Among them, d ₉₅ is the particle size corresponding to the cumulative percentage under the sieve of 95%;

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