technical report on fellowship-capacitation about metallurgical … · technical report on...

TECHNICAL REPORT ON FELLOWSHIP-CAPACITATION ABOUT METALLURGICAL PROCESSES

Summary of the activities developed in the theoretical and

practical training at the University of British Columbia,

Vancouver, Canada

Mining address

Geoscientists address Laboratories

Quito, 02/07/2018

© 2018 by the University of British Columbia and Canadian International Resources and Development Institute (CIRDI).

The material in this publication is copyrighted. Quoting, copying, and/or reproduc-ing portions or all of this work is permitted provided the following citation is used:

Tapia, L., Barona, D. (2018). TECHNICAL REPORT ON FELLOWSHIP-CAPACITATION ABOUT MET-ALLURGICAL PROCESSES. Canadian International Resources and Development Institute (CIRDI)

i

Canadian International Resources and Development Institute

Vancouver, British Columbia, Canada

www.cirdi.ca

[email protected]

Program undertaken with the financial support of the Government of Canada provided through Global Affairs Canada.

Programme réalisé avec l’appui financier du gouvernement du Canada agissant par l’en-tremise d’Affairs mondiales Canada.

CONTENTS

INSTITUTIONAL INFORMATION ................................................................................. 1

1. BACKGROUND ....................................................................................................... 2

2. OVERALL OBJECTIVE .............................................................................................. 3

3. DEVELOPMENT ...................................................................................................... 3

3.1 Sampling ................................................................................................................. 3

3.2 Mechanical preparation of samples in laboratories INIGEMM ....................... 3

3.3 Development internship ...................................................................................... 4

4. RESULTS ................................................................................................................. 7

4.1 Processes performed ........................................................................................... 7

4.2 Mechanical sample preparation ......................................................................... 7

4.3 Gravimetric concentration ................................................................................... 8

4.4 Flotation ...............................................................................................................10

4.5 Cyanidation ..........................................................................................................13

5. CONCLUSIONS ..................................................................................................... 15

6. RECOMMENDATIONS .......................................................................................... 15

7. ANNEXES .............................................................................................................. 15

7.1 Photo collection ...................................................................................................16

iii


LIST OF TABLES

Table 3.1. Identification and location of samples 6

Table 3.2 Activities in Vancouver, Canada 7

Table 4.1 Lease of studies 10

Table 4.2 Test results centrifugal concentration 12

Table 4.3 Test results float (200 microns) 14

Table 4.4. Results waterline (74 microns) 16

Table 4.5 Test results cyanidation 17

LIST OF FIGURES

Figure 4.1. Flowchart mechanical sample preparation 10

Figure 4.2. Flowchart gravity concentration 11

Figure 4.3. Comparison of results of gravimetric concentration 13

Figure 4.4. Flowchart flotation 13

Figure 4.5. Comparison of results of flotation (200 microns) 15

Figure 4.6. Comparison of results of flotation (74 microns) 16

Figure 4.7. Cyanidation flowchart 17

Figure 4.8. Comparison of results cyanidation 18

Figure 7.1 Facilities metallurgical laboratory at UBC 19

Figure 7.2 Working meeting Dr. Bern Klein, Eng. James Seiler, Eng. Luis Tapia, Eng. Diego Barona 20

Figure 7.3 Visit to metallurgical laboratory MET-SOLVE 20

Figure 7.4 Test gravimetric concentration in MET-SOLVE 20

Figure 7.5 Test cyanidation in MET-SOLVE 21

Figure 7.6 Test flotation MET-SOLVE 21

Figure 7.7 Primary crushing UBC 21

Figure 7.8 Secondary crushing UBC 22

Figure 7.9 Sieving UBC 22

Figure 7.10 Grinding UBC 22

Figure 7.11 Coning and quartering in UBC 23

Figure 7.12 Gravimetric test concentration UBC 23

Figure 7.13 Talk on flotation 23

Figure 7.14 Test flotation UBC 24

Figure 7.15 Test cyanidation UBC 24

Figure 7.16 Samples obtained in various tests for later laboratory analysis 24

1


INSTITUTIONAL INFORMATION

EXECUTIVE DIRECTOR: M.S. Martin Cordovez Dammer

GENERAL TECHNICAL COORDINATOR: M.S. Gonzalo Guerrón

DIRECTOR OF GEOSCIENCE LABORATORIES:M.Sc. Aracely Lima

DIRECTOR OF GEOLOGY: Eng. Solomon Brito

DIRECTOR OF MINING, METALLURGY AND ENVIRONMENTAL (E): Eng. Edwin León

TECHNICAL TEAM:

Eng. Luis Tapia Metallurgy Specialist

Eng. Diego Barona Chemical Specialist

PRODUCED BY: REVIEWED BY: APPROVED BY:

Eng. Luis Tapia

Eng. Diego Barona

Eng. Edwin León

DIRECTOR OF MINING (E)

M.Sc. Aracely Lima

DIRECTOR OF LABORATORY

Geoscientists

M.S. Gonzalo Guerrón

GENERAL TECHNICAL

COORDINATOR

2


1. BACKGROUND

1. On March 21, 2017, Mr. Deputy Minister of Mines of Ecuador Galo Armas through the memo-randum no. MM-VM-ME-2017-0074 formalizes the logical framework of the Education Project for transformation of Artisanal Small Scale Mining in Ecuador (TransMAPE) to Deputy Director of Programs of the Canadian International Resources and Development Institute (ICSID) Kirt-sen Dales.

2. The logical framework lists the final result as “1000 Miners Artesanales and Small Scale MAPE trained adopt and implement practices friendly mining environment, safe and economically”, in a period of 5 to 10 years. Additionally, it sets intermediate results as “integration of national goals through a training program for the transformation of artisanal mining to small-scale mining in southern Ecuador, aimed at strengthening capacities in mining practices respectful of the environment, safe and economically efficient “.

3. The product 1111, corresponding to “Alternative economically viable methods for recovering gold, mercury, using a training plan including mining operators permit, artisanal miners pend-ing, and mining and jancheras operators vision and regularization organization; considering complementing the metallurgical laboratory INIGEMM with sustainability vision into the MAPE and design of pilot plants according to the characteristics of each sector “, it has planned an internship-training for two professionals INIGEMM in University of British Columbia in Vancou-ver, Canada, and the product has the following activities related to the internship:

Definition of interns.

o Collection of 4 samples of the mining areas of Ecuador.

o Performing the internship-training in Canada by processing the samples in the labora-tories of the University of British Columbia and Met Solve.

o Defining methods of extracting gold more efficient to avoid the use of mercury.

o Definition of equipment needed for the implementation of the INIGEMM metallurgical laboratory.

o Selection and purchase of metallurgical equipment.

o Equipment installation and commissioning of laboratory INIGEMM metallurgy.

o Collection of new samples of the mining areas of Ecuador.

o Flow metallurgical research, replicating the processes performed in Canada. (prelimi-nary stage).

o Canadian experts to visit the laboratory facilities of INIGEMM.

o Analysis of results.

o Pilot plant design.

o Sampling and research metallurgical flow (final stage).

o Dissemination of results and training miners.

4. Official letter no. MM-MM-2017-0183-OF, of 17 March 2017, the Ministry of Mining extends the invitation of the Canadian Institute for International Resources and Development (ICSID) for two technicians involved in INIGEMM an internship training at the University of British Colum-bia in Vancouver - Canada, April 5 to May 7 this year (including 2 travel days), with all expenses covered by the CIRDI.

3


5. The delegation of engineers Luis Tapia and Diego Barona to participate in the internship is giv-en by official no. INIGEMM-INIGEMM-OF-2017-0111 of 20 March 2017 to turn the mining min-istry formalizes such participation, through job no. MM-VM-2017-0037-oF, of 23 March 2017.

2. OVERALL OBJECTIVE

Inform the activities and results of the internship-training metallurgical tests performed at 4 samples of mining areas in Ecuador, in the city of Vancouver, Canada.

3. DEVELOPMENT

3.1 SAMPLINGThe samples were collected in the mining districts of Canton Ponce Enriquez in the province of Azuay and in the cantons of Zaruma and Portovelo in the province of El Oro, as shown in the table 3.1:

Table 3.1. Identification and location of samples

Sample Sector UTM coordinates Weight (kg)PE-01 Ponce Enriquez - Mina Jerusalem 641 750E; 9663 050N 30PE-02 Ponce Enriquez - Mina Queen Swan

(Jancheras)642 506E; 9659 370N twenty

ZA-01 Zaruma - Mina Pillacela 654 953E; 9592 749N 30PV-01 Portovelo - Mina Eduardo Santos 653 993E; 9590 019N 30

Due to the complexity of the sampling of both the particle size and quantity of material, the collection method consisted of taking random rocks with the assistance of a qualified geologist to ensure the presence of ore vein as mineral sterile.

3.2 MECHANICAL PREPARATION OF SAMPLES IN LABORATO-RIES INIGEMMThe samples collected in the field were given to the analytical laboratory INIGEMM, and they were processed as follows:

- Reception

- Labeled

4


- Arrangement of stainless steel trays

- Drying at 60 ° C for 48 hours

- Grinding to a size of about 5 cm

- Packaging in plastic containers

- Placement of samples in suitcases

3.3 DEVELOPMENT INTERNSHIPThen the table 3.2, Activities during the internship is presented:

Table 3.2 Activities in Vancouver, Canada

DATE ACTIVITIESApril 5, 2017 Travel Quito - VancouverApril 6, 2017 Visit laboratories Coal & Mineral Processing Laboratory (CMP Lab) of the Univer-

sity of British Columbia (UBC)April 7, 2017 Meeting with Bern Klein and James Seiler (UBC), Mikhaela Meznaric and Colón

Velázquez (ICSID), Ish Graywald and Jonathan Tan (METSOLVE), Luis Tapia and Diego Barona (INIGEMM) to define the activities undertaken with the 4 samples collected.Meeting facilities Canadian International Resources and Development Institute (ICSID), where the presentation was held INIGEMM, its mission, vision, achieve-ments, ongoing projects and expectations of internship training.Approval of the following online courses for entry into laboratories CMP:Introduction_to_Lab_SafetyNew_Young_Worker_Safety_Orientation

April 10, 2017 Organization and arrangement in containers of PE-01, PE-02, ZA-01 and PV-01 samplesmechanical preparation of PE-02 sample (20 kg), the following operations are performed:Grinding to a grain size <3 cmGrinding to a grain size <1 cmGrinding to a grain size of <5 mm

April 11, 2017 - Classes with Dr. Bern Klein on: “Processing of Precious Metals Ores”

- mechanical preparation of PE-02 sample, the following processes were performed:

· Grinding to a grain size <1.4 mm

· Crazing of 10 samples of 1 kg each.April 12, 2017 - Visit to the laboratory MET-SOLVE activities:

· Welcome to the metallurgical laboratory

· Tour of its facilities

· Home metallurgical test with PE-02 shows: Sieving, Concentration Centrifuges

5


April 13, 2017 - Metallurgical tests MET-SOLVE:

· Centrifuges concentration

· Sieving

· PanningApril 17, 2017 - Cyanidation tests (Leach bottle) in MET-SOLVE:

· Sample Preparation

· Sample collection at different time intervals

· titration

· Separation of samples for chemical analysis.April 18, 2017 - Flotation tests in METSOLVE:

· Sample preparation and equipment

· Sample Conditioning

· Flotation

· Obtaining concentrates and tailings

- Form filling for laboratory analysis

- Data review sieving

- MS Analytical lab visit

April 19, 2017 - Mechanical preparation of PE-01, ZA-01 and PV-01 samples in UBC, which operations were performed.

· Grinding to a grain size <3 cm

· Grinding to a grain size <1 cmApril 20, 2017 - mechanical preparation of PE-01, ZA-01 and PV-01 samples UBC:

· Grinding to a grain size of <5 mm

- Preparation of draft document metallurgical equipment for INIGEMMApril 21, 2017 - mechanical preparation of PE-01, ZA-01 and PV-01 samples UBC:

· Grinding to a grain size <2 mm

· Obtaining 10 representative subsamples of each of the mineralsApril 24, 2017 - Concentration assays Centrifuga of PE-01, ZA-01 and PV-01 UBC samples

according to the procedure:

· Mixture 25% solids of about 5 kg sample

· Centrifugal concentration

· Panning concentration

· Grinding centrifugal concentrator tailingsApril 25, 2017 - Concentration assays centrifuged at tailings first centrifuge test concentra-

tion of PE-01, ZA-01 and PV-01 in UBC, the following samples were made:

· Mixture 25% solids of approximately 5 kg sample

· centrifugal concentration

· Platoneo concentrate

6


April 26, 2017 - Classes with Dr. Bern Klein on: “Leaching”

- Preparation of equipment and reagents for carrying out the flotation testsApril 27, 2017 - Flotation talk with Eng. Santiago Seiler.

- Flotation tests, the following processes were performed:

· Mixture 50% solids of about 1 kg of sample

· Conditioning

· Flotation

· Getting tailings and concentratesApril 28, 2017 - Flotation tests, the following processes were performed:

· Grinding

· Mixture 50% solids of about 1 kg of sample

· Conditioning

· Flotation

· Getting tailings and concentratesMay 1, 2017 - Cyanidation tests of PV-01 and ZA-01 samples, according to the following

procedure:


· Stabilization (pH adjustment)

· Cyanidation (0, 1, 3, 6 and 24 hours of control)May 2, 2017 - Control at 24 hours of testing cyanidation samples PV-01 and ZA-01

- Obtaining cyanidation tailings

- Cyanide waste disposalMay 3, 2017 - Cyanidation tests of the PE-01 and PE-02 samples, according to the follow-

ing procedure:


· Stabilization (pH adjustment)

- Cyanidation (0, 1, 3, 6 and 24 hours of control)May 4, 2017 - Control at 24 hours of testing cyanidation of PE-01 and PE-02 samples

- Obtaining cyanidation tailings

- Cyanide waste disposal May 5, 2017 - Sample preparation (concentrates and tailings) processes: centrifugal

concentration, floating and cyanidation for the determination of gold in an external laboratory.

April 6, 2017 Travel Vancouver - Quito

7


4. RESULTS

4.1 PROCESSES PERFORMEDTests performed on samples were processed both in a MET-SOLVE external metallurgical laboratory and in the metallurgical laboratories in the Norman B. Kevil Institute at UBC. The processing location is shown in Table 4.1:

Table 4.1 Location of studies

Sample Mechanical preparation

Centrifuges concentration Flotation Cyanidation

PE-01 * UBC UBC UBC UBCPE-02 * UBC MET-SOLVE MET-SOLVE MET-SOLVE / UBCZA-01 * UBC UBC UBC UBCPV-01 * UBC UBC UBC UBC

* The subsamples obtained in various tests were sent to the laboratory MS Analytical

4.2 MECHANICAL SAMPLE PREPARATIONMechanical sample preparation involves reducing the particle size by equipment such as crushers, mills, and grinders. To ensure a certain grain size, a sieve is used with an opening defined by the needs of the tests is used. A process of quartering, which consists of homogenization and sample division, is per-formed to obtain representative samples. The samples were processed in size reduction and obtainment of representative subsamples in accordance to the following flowchart in UBC laboratories.

Muestra

Trituración A(trituradora de mandíbulas)

Trituración B(Molino de cono)

Trituración C(mini trituradora de mandíbulas)

Screeningmalla 14 (1,4mm)

>1.4mm Molienda(molino de martillos)

Splitting< 1.4mm

Screeningmalla 14 (1.4mm)

>1.4mm

1 muestra de 20 kg

10 muestras de 1 kg

5 cm

< 3cm

< 1cm

< 5mm

< 1.4mm

Figure 4.1. Flowchart mechanical sample preparation

8


4.3 GRAVIMETRIC CONCENTRATIONGravity concentration is a unit operation consisting of mineral separation by specific grav-ity by the action of gravity, which in this case is due to the action of centrifugal force. Sam-ples were processed by centrifugal concentration according to the following flowchart.

Figure 4.2. Flowchart gravity concentration

Test parameters centrifugal concentration

Samples for this test were prepared as 25% pulp solids. The decreased particle size was achieved by using a grinding roller on two different milling times. The table the 4.2 presents results obtained in the process of centrifugal concentration. Figure 4.3 demonstrates the behavior of the minerals analyzed in the following process:

9


Table 4.2 Test results centrifugal concentration

dp = 200 um PE-02 PE-01 ZA-01 PV-01

products Mass (%)

Au Mass (%)

Au Mass (%)

Au Mass (%)

Au(G / t) (%) (G / t) (%) (G / t) (%) (G / t) (%)

Panning of Concentrate 1 1.63 127.44 10.5 0.70 5.45 0.27 0.30 669.37 18.21 0.42 76.03 3.82Panning of Concentrate 2 1.35 367.66 25.1 1.14 2.81 0.22 0.71 360.32 23.54 1.06 139.50 17.63Panning of Concentrate 3 0.30 878.55 13.2 0.71 1.46 0.07 0.76 309.32 21.70 0.99 66.76 7.89Panning Tail-ings 3 0.87 22.04 1.0 0.91 39.39 2.52 0.69 76.03 4.80 1.08 25.59 3.30Gravimetric Concentrate 3 1.17 239.53 14.2 1.62 22.81 2.59 1.45 198.83 26.50 2.07 45.28 11.19Total concen-trate 4.15 236.95 49.8 3.46 12.74 3.08 2.46 302.25 68.25 3.56 77.03 32.64

Tailings con-centration 95.85 10.36 50.2 96.54 14.37 96.92 97.54 3.54 31.75 96.44 5.86 67.36Calculated head grade 100 19.75 100.0 100 14.31 100 100 10.88 100 100 8.39 100

* Displays processed MET-SOLVE

Figure 4.3. Comparison of results of gravimetric concentration

In the Figure 4.3, it was observed that the mineral ZA-01 (68.25%) achieves a higher gold recovery and a low per-centage of concentrated mass (2.46%) compared to the total mass of the assay. Similarly, it was observed that the PE-01 mineral is not practical for gold recovery of this type because its recovery is less than 10% of gold available in the sample (3.1%). For the jancheras’ ore, PE-02 shows that half the available gold (49.8%) is recovered, which reveals that it can be considered as an alternative to increase the degree of concentration of the final product.

10


4.4 FLOTATIONFlotation is a process of concentration consisting of three gas-liquid-solid phases, and which aims to separate mineral species through selective adhesion of the particles to air bubbles. Samples were processed through different steps, i.e. in the same flotation cell after each collection of concentrate, more reagents were added, prior to measuring pH to collect a concentrated again, as shown in Figure 4.4:

Concentrado 1

Relave 1

Concentrado 2

Relave 2

Concentrado 3

Relave 3

<1.4 mm

EspumanteColector Espumante

Colector EspumanteColector

CELADA DEFLOTACIÓN

Relave 4

EspumanteColector

Concentrado 4

Figure 4.4. Flowchart flotation

The PE-02 sample was processed in MET-SOLVE with the last tailings centrifugal concentration; the remaining mineral assays were performed with head minerals at the UBC facilities.

Test parameters selective flotation of sulfides

Samples for this test were prepared as 50% pulp solids, with the addition of flotation reagents (Collector Kax-0.5% Foaming F250-20 g / t, Foaming MIBC-20 g / t) and recollection concentrates according to the amount of recollected mass. It should be noted that trials were done with two particle sizes (200 and 74 microns) were made. The results obtained for the particle size of 200 µm are shown in Table 4.3 and in Figure 4.5.

Table 4.3 Flotation test results (200 microns)

dp = 200 um PE-02 PE-01 ZA-01 PV-01

products Mass (%)

Au Mass (%)

Au Mass (%)

Au Mass (%)

Au(g/t) (%) (g/t) (%) (g/t) (%) (g/t) (%)

Concentrate 1 11.6 43.7 48.4 2.8 249.1 35.7 2.3 298.8 73.1 12.1 65.7 75.1

Concentrate 2 15.9 22.9 34.9 0.9 250.4 11.5 0.5 126.9 6.5 5.8 18.8 10.3

Concentrate 3 5.4 16.5 8.5 0.6 491.1 16.3 0.6 103.9 6.8 5.2 15.1 7.3

Concentrate 4 2.8 9.1 2.5 5.2 56.9 15.4 2.3 16.2 3.6

Total Concentrate 35.8 27.6 94.3 9.5 160.1 78.9 3.4 239.0 86.4 25.4 40.2 96.3

Flotation tailings 64.2 0.9 5.7 90.5 4.5 21.1 96.6 1.3 13.6 74.6 0.5 3.7Calculated head grade 100.0 10.5 100.0 100.0 19.3 100.0 100.0 9.4 100.0 100.0 10.6 100.0

11


Figure 4.5. Comparison of results of flotation (200 microns)

In the figure 4.5, It is observed that mineral achieves higher gold recovery is the PV-01 (96.03%), just as the percentage of recovery having the PE-02 (95.2%) mineral is very similar, however percent-ages concentrate mass they are also high 25.4% and 35.8% respectively. Furthermore, the ZA-01 and PE-01 mineral exhibit recoveries 86.4 79.8% respectively. While the concentrations are lower compared with PV-01 and PE-02, the percentage of concentrated mass (3.4 and 9.5%, respectively) is also lower. For this reason, it is considered that minerals ZA-01 and PE- 01 fulfill the objective of the concentration, to have less mass but higher content. Additionally, it is noted that in the PE-02 sam-ples and PV-01, gold is associated with quartz, which means that they are not only prone to flotation concentration.

Test parameters selective flotation of sulfides (74 microns)

Considering the particle size influences the flotation recovery, the PE-01, PV-01 and ZA-01 samples were processed in the laboratories of UBC with a granulometry of approximately 74 .mu.m. The samples for this test were first reduced in size with the use of a roller mill (replicating grinding times of centrifugal concentration). The respective samples were then prepared as pulp at a percentage of 50% solid for the flotation process, with the addition of a reagent (Collector Kax-0.5% Foaming F250-20 g / t, Foaming MIBC-20 g / t) and recollection of concentrates according to the amount of recollected mass (development of expertise is needed for this operation). The results obtained for the particle size of 200 .mu.m are shown in table 4.4 and in the figure 4.6.

12


Table 4.4. Results waterline (74 microns)

dp = 74um PE-01 ZA-01 PV-01

Products Mass (%)

AuMass (%)

AuMass (%)

Au(G / t) (%) (G /

t) (%) (G / t) (%)

concentrate 1 2.1 165.1 32.3 2.5 30.3 82.6 6.0 116.0 70.0

concentrate 2 1.3 83.6 9.9 0.8 14.9 12.2 4.0 11.6 4.6

concentrate 3 2.3 41.5 8.9 7.2 27.5 19.6

concentrate 4 5.4 45.2 22.7

Total concentrate 11.1 71.6 73.8 3.3 26.8 94.8 17.2 54.9 94.2

flotation tailings 88.9 3.2 26.2 96.7 0.1 5.2 82.8 0.7 5.8Calculated head grade 100.0 10.8 100.0 100.0 10.9 100.0 100.0 10.0 100.0

Figure 4.6. Comparison of results of flotation (74 microns)

Figure 4.6 shows that both the mineral ZA-01 as the PV-01 have high recoveries 94.8 and 94.2% re-spectively, but relative to the mass of concentrated mineral ZA-01 is 3.3% of the total mass of the test, while PV-01 is 17.2% by mass. Additionally, it is noted that the degree of finer grind (74 microns) allows the recovery of gold is higher in a concentrated small volume compared to those presented in figure. However, the sample PV-01 maintains a high percentage of concentrate mass.

13


4.5 CYANIDATIONCyanidation is a metallurgical for gold extraction of a mineral technique. This technique transforms gold metal cyanide anions in complexes, soluble in the solution, by a process in which the extraction of soluble matter from a mixture as performed by a liquid solvent. Samples were processed by cyanidation accord-ing to the following flow diagram:

medición y ajustede pH = 11

1 hora

Muestra 1(solución cianurada)

NaCNCaO


0 horas 3 horas 6 horas


medición y ajustede pH = 11 medición de pH

24 horas

Muestra 2(solución cianurada) Muestra 3

(solución cianurada) Muestra 4(solución cianurada)

Botella decianuración

Figure 4.7. Cyanidation flowchart

Test parameters

Samples for this test were prepared as 25% pulp solids, with addition of sodium cyanide. Sample collec-tion was carried out every 1, 3, 6 and 24 hours for determining results of gold leaching. The results are shown in Table 4.5.

Table 4.5 Cyanidation test results

PE-02 PE-01 ZA-01 PV-01

Time (hours)Pulp weight (g)

Au Pulp weight (g)

Au Pulp weight (g)

Au Pulp weight (g)

Au(G / t) (%) (G /

t) (%) (G / t) (%) (G /

t) (%)

one 3004.0 1.8 26.1 3006.2 0.8 12.2 3001.0 1.7 29.7 3001.0 1.0 15.4

3 2994.7 2.8 41.0 2996.2 1.5 22.1 2991.0 3.0 54.3 2991.0 2.5 37.7

6 2985.6 3.4 50.2 2986.4 1.8 26.7 2981.2 3.8 67.9 2981.2 3.4 51.7

24 2976.2 3.8 55.5 2976.4 2.0 30.3 2971.2 4.0 72.4 2971.2 4.1 61.0

Residue 1950.0 4.7 44.5 1950.0 7.0 69.7 2009.0 2.3 27.6 1819.1 4.3 39.0Calculated head grade 10.5 100.0 10.0 100.0 8.2 100.0 10.2 100.0

14


Figure 4.8. Comparison of cyanidation results

In the Figure 4.8, it can be noted that the four mineral samples exhibit the same behavior to the cy-anidation and granulometry tests, of which it is seen that the mineral ZA-01 has the highest recov-ery (72.4%). Conversely, it is observed that the mineral PE- 01 only achieves 27% with cyanidation, for which it could be attributed to the fact that this mineral presents refractory gold. PV-01 and PE-01 minerals have a 60% recovery supplementing the recoveries obtained in other processes.

15


5. CONCLUSIONS

1. Mechanical processes, such as sample preparation, gravity concentration, flotation and cyani-dation, are essential for determining the appropriate metallurgical processing for each sample.

2. The design of a metallurgical process comprises of combining unit operations, so it is essential to observe the behavior of the minerals in each process (concentration, flotation, cyanidation, etc.).

3. Flotation is an operation that requires experience, because the control of this test is performed visually, and therefore the performance of this assay will improve after each test that is done

4. The PE-01 has shown better results in flotation with a 79.8% recovery, but recoveries in other assays are low. This is due to a possible presence of refractory gold associated with sulphides.

5. Gold associated with quartz presents a very low concentration ratio.

6. The PE-02 sample exhibits better recovery in the flotation reaching an 80% recovery, the gravi-metric concentration reaches 50% and 50% cyanidation.

7. The PV-01 has shown strong results in flotation for both granulometry of 200 .mu.m and 74 .mu.m, achieving 90% recovery.

8. ZA-01 has shown high recoveries in all the tests, which is why this mineral can be considered for an experimentation of a serial process.

6. RECOMMENDATIONS

1. Implement the metallurgical laboratory INIGEMM.

2. Replicate metallurgical tests conducted in Canada.

3. Create procedures manual, as the purchased equipment.

4. Perform the tests in both serial and batches of the minerals in order to be able to analyze the overall recoveries of minerals.

5. Analyze alternative treatment processes for refractory ores.

16


7. ANNEXES

7.1 PHOTO COLLECTION During the fellowship/training the following activities were carried out:

- Visit laboratories Coal & Mineral Processing Laboratory (CMP Lab) of the University of British Columbia (UBC)

Figure 7.1 Metallurgical laboratory facilities at UBC

Figure 7.2 Work meeting Dr. Bern Klein, Eng. James Seiler, Eng. Luis Tapia, Eng. Diego Barona

17


Figure 7.3 Visit to the metallurgical laboratory MET-SOLVE

Figure 7.4 Gravimetric assay concentration MET-SOLVE

Figure 7.5 Cyanidation test in MET-SOLVE

18


Figure 7.6 Flotation test in MET-SOLVE

Figure 7.7 primary crushing at UBC

19


Figure 7.8 regrind in UBC

Figure 7.9 Sieving UBC

Figure 7.10 UBC milling

20


Figure 7.11 Coning and quartering at UBC

Figure 7.12 Gravimetric assay concentration UBC

Figure 7.13 Talk on flotation

technical report on fellowship-capacitation about metallurgical … · technical report on...

Documents