WO2010019062A1

WO2010019062A1 - The procedure for obtaining metal concentrate from ore complex

Info

Publication number: WO2010019062A1
Application number: PCT/RS2008/000035
Authority: WO
Inventors: Ljubomir Dragosan; Milorad Grujic; Miroslav Vrhovsek; Igor Barbulovic
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-13
Filing date: 2008-11-25
Publication date: 2010-02-18
Anticipated expiration: 2011-02-13
Also published as: RS20080357A

Abstract

According to this invention, a process for obtaining zinc, lead, gold and silver concentrate from a complex low - concentration ore. The process consists of several stages: three - staged basic grinding and two - staged classification, conditioning, basic and control flotation with exactly specified values of kinetic constants for the whole period of time. The process of purification is flexible, so that different concentrations of elements are used for two -, three - and four - staged grinding. Listed possible technical - technological adjustments are conducted momentarily and with no difficulties. Additional grinding of the control concentrate, separation of solid and liquid phases is done in the condensers and press filters. Based on the content of elements in the products of concentration and technical - technological parameters and work of the system on the whole on one side and general production goals on the other, handling system of control and regulation of the process is used.

Description

THE PROCEDURE FOR OBTAINING METALS FROM ORE COMPLEX

Domain of science that the invention refers to

In general, the invention refers to separation of solid materials by subsequent processing of the concentrate by flotation, and in particular - to the domain of the combined method of concentration of useful components of zinc, lead, gold and silver from complex ores of Zn, Pb, Au, and Ag with low percentage.

According to the International Patent Classification, the invention is sorted, i.e. classified and marked with classification symbols B03D 1/08 and B03B 5/28.

Technical problem

The technical problem solved by this invention is: how to provide a commercial collective concentrate with Zn+Pb concentration above 50% from a low-percentage complex ore with high exploitations and minimal production costs for extracting Zn, Pb, Au and Ag by application of three-staged basic grinding and two-staged classification, conditioning, providing humidity in press-filters, basic and control flotation with usage of the operational control and process regulation system.

State of the technology

Flotation concentration has a great significance and is widely applied as a branch of science, especially in the conditions of the exploitation of complex ores with lower and lower percentages. In the plants for preparation of raw minerals in the world, a very great number of exploitation methods are used, we will give some: gravitational, chemical, electro - magnetic, CIP (carbon in pulp) and many other combined methods.

Which method will be used depends on mineral - petrography and physical - chemical properties of the raw material as a carrier of the useful elements, as well as on the properties and concentration level of the elements. We should mention that the technologies listed above are used for valorization of the useful elements of primary and secondary bodies.

The process used here is original, defined on the basis of fundamental, laboratory and half - industrial trials on the Majdanpek ores lasting several years.

The new process enables valorization of more useful components: zinc, lead, gold and silver, which the processes mentioned above, are not able to do. Also, the new process progresses in parallel with the concentration of the minerals of copper, gold, silver, platinum and palladium, which gives good exploitations of Zn, Pb, Au and Ag and a final concentrate with a market value(Zn+Pb>50%).

Searching the patent documentation and academic literature for this domain did not reveal any similar solution of this technical problem.

Presentation of the essence of the invention

The invention refers to the process of extracting useful minerals of zinc, lead, gold and silver from small ore bodies of a complex ore. Mineralization is morphologically represented by regular lenses and wires, and the systems of the flotation concentration are of medium capacity.

The process consists of several stages: three - staged basic grinding and two - staged classification, conditioning, basic and control flotation with exactly specified values of the kinetic constants for the whole period of time. The process of purification is flexible, so different concentrations of elements are used for two - , three - and four - staged purification. Listed possible technical - technological adjustments are conducted momentarily and without difficulties. Additional grinding of the control concentrate, separation of solid and liquid phases is done in the condensers and press - filters. Based on the element concentration in the concentration products and technical - technological parameters and the work of the plant on the whole on one side, and the general productions goals on the other, handling system of control and regulation of the process is used.

It is well known that the standard procedures of the flotation concentration or other similar methods of concentration do not enable successful valorization of raw materials with low metal concentration, very complex mineral contents and structural characteristics. The process which is the subject of this invention gives a significant contribution to usage of new and more and more complex processes which valorize useful components - zinc, lead, gold and silver. The adopted technology for production of the collective concentrate is in many aspects new in flotation plants both in Serbia and in the world. With this system, the views that small veins of complex ores with a low concentration of useful metals can be exploited profitably only with usage of such complex technology have prevailed.

Short description of the pictures of the scheme

The invention is described in detail in the examples of conduction given in the scheme in which:

Picture 1 represents the scheme of concentration of the polymetalic ore TENKA Majdanpek,

Picture 2 represents disposition of the automatics appliances,

Picture 3 represents the scheme of the filtration of the collective concentrate Zn-Pb in the press - filter, and

Picture 4 represents the vertical cross-section of the press - filter. Detailed description of the invention

In the conditions of processing ores with lower and lower concentrations, far greater concern must be paid to finding the possibilities for complex use, i.e. maximal possible valorization of the useful components in the ore. Based on the fundamental, laboratory and half - industrial trials, the way of occurrence and proportion of useful, accompanying and minerals of tailing, which provided a basis for the new procedure of the technological process of concentration of complex ores. The procedure of concentration of complex ores, given in the pictures 1, 2 and 3, offers a collective concentrate (Zn, Pb) of market value with Au and Ag.

The invention refers to the procedure of extracting useful minerals of zinc, lead, gold and silver from small ore bodies of a complex ore. The mineralization is morphologically represented by regular lenses and wire so the systems of the flotation concentration are of a medium capacity.

The procedure consists of several stages:

— Three — staged basic grinding and two - staged classification with 80% fineness minus 0,0495 mm;

— Conditioning, basic and control flotation with exactly specified values of kinetic constants for the whole period of time;

— The process of purification is flexible: o Two - staged purification is used in ore concentrating with proportion of Zn in the ore above 2,5% o Three - staged purification is used for the ore with proportion of Zn in the ore below o Four - staged purification is used in cases of increased proportion of Cu in the ore ranging from 0,30 to 0,40%

Following possible technical and technological adjustments can be made momentarily and without difficulties.

— Additional grinding of the control concentrate to the fineness of 70-80% minus 0,020 mm;

— Separation of solid and liquid phase, conducted in the condensers and press — filters;

— Based on the contents of elements in the concentration products and technical - technological parameters and the work of the system on the whole on one side and general production goals on the other, handling system of control and regulation of process is used.

In the industrial work following results are projected: Table 1

• Hour capacity Q=71,6 t/h

• Fineness of grinding P₈₀=72,5% minus 0,02mm,

• Exploitation Iz_n=77,30%

Ipb=78,l l% IA_U=51 ,00% I_Ag=77,00%

• Concentrate quality Zn=38,96%

Pb=I 1,67% Cu=3,17% Au=2,94 g/t Ag=289,00 g/t

The proposed procedure has following characteristics:

— Three - staged grinding o In the first grinding stage the fineness of the ground ore is P'g_O=47Oμm o In the second grinding stage the fineness of the ground ore is P"₈o=l 13μm o In the third grinding stage the fineness of the ground ore is P"'₈₀=49,5μm

— Two - staged classification o In the first classification stage separation is P'_r=20%+l 18μm and P'_r=50%+24μm o In the second classification stage separation is P"_r=20%+53μm and P"_r=50%+24μm

— An independent cell (MG - 8,5) is implemented in the grinder - hydrocyclone system, which separates large free grains of the useful minerals in order not to be returned to the grinder and over ground.

— It has a flexible solution with momentary adjustment of application: two, three or four purifications, according to different characteristics of the raw mineral material.

A new constructive solution for press filters is used, Picture 4, giving the conditional moisture of the concentrate of 6-8% H₂O, which is not possible to achieve with classic filters (disc filter, drum filter, tape filter) at this fineness of the concentrate (ZnPb), while drying great amounts of ZnPb concentrate, 28 000 t/year is not economical. In the mining, the presses have the air blow along the whole surface of keik, due to what drying of keik of Δ=25mm to 35 mm ranging from 6,0 to 8,0% of H₂O is achieved. Press filter, Picture 4, has a vent (9) for pulp exit, upper frame (4), plates of propylene bar (3), beneath which there is the tin of the frame (7) on the upper side, and on the lower side there is the membrane (8), beneath which there is space for keik formation (10) and filtrate exit (11), and on the left side there is the lower frame of the plate with the gasket (5) and canvass (6), while on the right side there is entrance for the pulp (1) which enters through five openings during t= 1,5 min.

Basics for the projection of the press filters (FOD, Majdanpek) are acquired from laboratory results, by treating Majdanpek collective concentrate ZnPb. Following dimension and capacity values were then assessed:

Area: F=32 m²

Number of plates : n=20

Area of a plate: F i = 1 ,6 m²

Dimensions of the press filter: 2,8x4,3 m

Dimensions of the plate : 90Ox 1720 mm

The capability of the listed constructive characteristics of the press filter for drying collective concentrate, with capacity of 6,2 t/h and fineness of P₈₀-49 μm, is reflected in the achieved work parameters:

Filling the press filter with concentrate: 1,5 min.

Emptying the pulp from the press filter: 1,0 min.

Emptying the concentrate in the press filter: 2,5 min.

The filtrate blowing-through: 4,0 min.

Total time of the cycle: t = 8,5 min.

Also, realized mass distribution was used for assessment of the efficacy of the work of press filters, shown in Table 2.

Mass distribution Table 2

Solidphase H₂O Pulp Pulp

Product t/h m³Zh t/h m³/h t/h m³/h Tn³Zh

Entry 6,20 1,33 6,20 6,20 12,40 7,53 1,65

Filtrate 0,00 0,00 5,66 5,66 5,66 5,66 1,00

Keik 6,20 1,33 0,54 0,54 0,74 1,87 3,60

Based on the parameters from Table 2, we can say that the constructive solution for press filters FOD, Majdanpek achieves filtration of the projected mass in industrial conditions, while the keik drying is of wideness 25 - 35 mm. Achieved result shows that the optimal size and geometry of the basic plate of the press filter is constructed, Picture 4.

According to that, working parameters of press filters are:

• Pumping the pulp in raises the membrane 8, and the air is pressed out through the membrane water drain. Filling with pulp raises the membrane to the tin frame 7.

• After filling the press with pulp through entrance 1 , the vent conducting water and air above the membrane is closed.

• At the same time, the vent conducting water on the membrane is opened. Because of the water pressure to the membrane, draining the keik 10 begins.

• Then the vent 9 for pulp release is closed, when the keik blow - through begins.

• At the same time, vent 11 for filtrate exit opens.

• Total duration of the process is t=8,5 min. During the process, work pressures are:

• Filtration 5,5

• Compression 8,0

• Blow - through 6,5

For comparison of press filter FOD, Majdanpek and Svedele (the greatest manufacturer in Europe), in Table 3 we show dimensional parameters of the process.

Dimensional parameters of the process Table 3

Parameter FOD, M-pek Svedela

Total duration of a cycle, min. 8,5 10,25

Necessary filtration volume, 1 376 413

Volume of the pulp/cycle/filter/, m³ 1,90 1,73

Solid phase mass/cycle/filter/, t 1,57 1,42

Greater efficacy of the proposed press filter is due to the greater amount of the air blown in according to the compared parameters. Also, the air penetration from the center to the periphery in all directions with shorter time of movement. This is confirmed by the shorter time of the cycle (1 ,75 min).

The final product of the whole procedure is a collective concentrate ZnPb, which is the carrier of the noble metals Au and Ag.

The effects of this procedure are: exploitation of zinc 77,30%, exploitation of lead 78,11%, exploitation of Au - 51,00% and exploitation of Ag - 77,00%.

Claims

PATENT REQUIREMENTS

1. Procedure for extracting zinc, lead, gold and silver from a complex low - concentration ore of small veins of complex ore with low concentration of useful metals: Zn=2,5%, Pb= 1,3%, Au=0,436 g/t, Ag=27,40 g/t, marked by providing P80= -0,0495mm by three - staged grinding and two - staged classification, and form the sand of the hydrocyclone in the independent cell collective concentrate ZnPb is extracted and is put together with the final concentrate, and the pulp in which are completely free grains of the useful elements is conditioned for 10 minutes with the content f the solid phase of 26% with adding reagents like aero 3418 A, potassium amyl xanthate (KAX) and copper sulfate CuSO₄, it is flotated with basic flotation of 20 min and purified, depending on the conditions, in two, three or four purifications, while the humidity of the concentrate of 6-8% H₂O is provided in the press filter.

2. The procedure, according to the Requirement 1, marked by the first purification lasting 15 min, the second 18 min and the third 20 min, while the produced concentrate has concentration of 38,96 mass % of Zn, 11,67 mass % of Pb containing 2,94 g/t of Au and 289,00g/t of Ag, and the exploitation is 77,30% Zn, 78,1 l%Pb, 51,00% Au and 77,00% Ag.

3. The procedure, according to the Requirements land 2, marked by filling of the press filter with the concentrate through the entrance (1) lasting 1,5 minutes, while the pumping the pulp in raises the membrane (8) to the tin frame (7), the vent conducting water and air above the membrane (8) is closed, and at the same time the vent conducting water on the membrane is opened and due to the pressure of water draining of keik begins, after which the vent for pulp exit (9) is closed when the keik blow - through begins, and at the same time vent for filtrate exit (11) is opened, while the total phase of the process is t=8,5min.

Signature of the Applicant