The Industrial Application of Ultrafiltation and Reverse Osmosis for the Recovery of Cu, Ag and CN from Gold Leach Liquors.

Transcription

1 The Industrial Application of Ultrafiltation and Reverse Osmosis for the Recovery of Cu, Ag and CN from Gold Leach Liquors. A.J. Monhemius Anglo Asian Mining plc 1

2 Disclaimer The information in this document is subject to updating, revision and amendment. This document neither constitutes nor forms nor should beconstructed as constituting or forming part of any offer or invitation to sell or any solicitation of any offer to purchase or to subscribe for any securities in Anglo Asian Mining PLC ( Anglo Asian Mining ) or any other body corporate or an invitation or inducement to engage in investment activity under section 21 of the UK Financial Services and Markets Act 2000 nor shall it or any part of it form the basis of or be relied on in connection with any contract therefore. This document does not constitute an invitation to effect any transaction with Anglo Asian Mining nor to make use of any services provided by Anglo Asian Mining. No reliance may be placed for any purpose whatsoever on the information contained in this document nor on assumptions made as to its completeness. No representation or warranty, express or implied, is given by Anglo Asian Mining, any of its subsidiaries or any of its respective advisers, officers, employees or agents, as to the accuracy, fairness or completeness of the information or opinions contained in this document or expressed in the presentation and, no liability is accepted for any such information or opinions (which should not be relied upon) or for any loss howsoever arising, directly or indirectly, from any use of this document or its contents or information expressed in the presentation. The information and opinions contained in this document and the presentation are provided as the date of this document and the presentation and are subject to change without notice. This presentation contains forward-looking statements that are based on Anglo Asian Mining's current expectations and estimates. Such forwardlooking statements involve known and unknown risks, uncertainties and other factors that could cause actual events or results to differ materially from estimated or anticipated events or results implied or expressed in such forward-looking statements. Factors that could cause such difference include changes in world commodities and equity markets, political developments in Azerbaijan, changes to regulations affecting Anglo Asian Mining's activities and other risks involved in the mining industry. Any forward-looking statement speaks only as of the date on which it is made and Anglo Asian Mining disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events or results or otherwise. Forward-looking statements are not guarantees of future performance and, accordingly, undue reliance should not be put on such statements due to the inherent uncertainty therein. This presentation has been prepared in compliance with English law and English courts will have exclusive jurisdiction over any disputes arising from or connected with this presentation. 2

3 Azerbaijan Geography *Gedabek 3

4 Flow diagram of the ore processing facilities at Gedabek Low Grade Ore U/F Gedabek Open Pit Mine Tailings Thickener High Grade Ore Grinding Resin-in- Pulp O/F Leach Thickener U/F Agitation Leach Plant O/F Loaded Resin Eluted Resin SART Cu/Ag ADR PLS Pond BLS Pond Sulphide Conc. Gold Doré Heap Leach Tailings slurry TMF Return water 4

5 Gedabek Process Plant 5

6 Typical Process Solution Compositions Copper mg/l Gold mg/l Silver mg/l Cyanide - WAD CN mg/l Free CN mg/l Calcium mg/l Sulphate mg/l 6

7 Flow diagram for the pilot plant tests Process water UF PLANT Suspended Solids RO Plant Feed Buffer Tank Process water Anti-scalant RO Plant Feed Tank RO PLANT RO Concentrate RO Permeate 7

8 Results from pilot plant tests 8

9 Flow diagram of the industrial UF/RO plant Process water 9

10 Gedabek Process Plant 10

11 Blank 11

12 Blank 12

13 Blank Sand Filters 13

14 Ultrafiltration Modules Blank 14

15 Reverse Osmosis Modules Blank 15

16 Blank RO Feed Pumps 16

17 Mean results from the industrial UF/RO plant (May 2018) Average clean water output: 400m 3 /day * The CN is free cyanide in all cases except for Final output which is the sum of Free + WAD cyanide 17

18 UF/RO Water Treatment Plant Cost Data Data for May 2018 Power consumption (month) = kwh Power cost (month) = 5140 AZN (USD 1 = 1.7 AZN) Clean water production (month) = m 3 (403 m 3 /day) Power consumption = 5 kwh/m 3 Unit cost = 0.41 AZN/m 3 = 24 cents US/m 3 c.f. Transported water from river (free at source); delivered cost 2.5 AZN/m 3 18

19 Conclusions Laboratory and pilot plant tests showed that a combination of ultrafiltration and reverse osmosis can be used to produce clean water from cyanide leach solutions that are saturated with calcium and contain up to at least one gram per litre of copper. An industrial-scale UF/RO plant has been built based on these test results that is designed to produce up to 60 m 3 /h of clean water. The performance of the industrial plant is as good as, if not better than, the test work results. The anti-scalant has performed as intended and has prevented fouling of the RO membranes, in spite of the high calcium content of the input solutions. 19