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macraes gold pressure oxidation

Macraes Operation - OceanaGold

2020-06-30  The operation consists of a large-scale surface mine, an underground mine, and an adjacent process plant inclusive of an autoclave for pressure oxidation of the ore. Its annualised gold production is split approximately 75% to open pit production and about 25% underground production.

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BENCHMARKING ENERGY EFFICIENCY – A CASE STUDY AT

Oceana Gold (New Zealand) Limited operates the Macraes Gold Mine near Dunedin on the South Island of New Zealand. The ore body is mineralogically complex and comparatively low grade requiring a series of unit processes and resulting in a relatively complex plant. As part Oceana of Gold’s ongoing Business Improvement program, a concerted effort has been made to focus on operational efficiency ...

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Macraes Gold Mine, Waitaki District, New Zealand

The first stage of processing involves flotation and yields a recovery rate of 86%, while the second stage of pressure oxidation and CIL has a recovery of 95%. The overall recovery of gold stands at 81%-82%. The process produces 92% pure doré bullion bars with

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Major Mines Projects Macraes Mine

2020-04-15  The Macraes Process Plant recovers gold by concentrating the metal into a relatively small fraction of flotation concentrate, oxidising the reground concentrate in a pressure oxidation autoclave, washing the oxidised residue and then utilising a carbon-in-leach process to recover gold from the residue. In detail the plant comprises:

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Macraes Gold Tungsten Project - CPC Engineering

CPC won the contract to complete the metallurgy and process plant component of a feasibility study for the Macraes Gold Tungsten Project for OceanaGold Corporation. The study consisted of a 3.0 Mtpy gold plant consisting of relocating the existing Pressure Oxidation circuit and all new additional equipment as well as a PFS level study into a 1.0 Mt/y tungsten concentrate plant to process high ...

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Pressure oxidation overview - ScienceDirect

2005-01-01  Pressure oxidation refers to the oxidation of sulfides, such as pyrite [FeS2] and marcasite [FeS2], at elevated temperature and pressure. Oxidation releases encapsulated gold grains from the sulfides and makes the oxidation residue of the ore or concentrate more amenable for gold recovery by cyanidation in a subsequent leaching step.

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Pressure-oxidation autoclave as an analogue for acid ...

In order to maximise gold extraction, a pressure oxidation plant was commissioned in 1999 which treated the sulfide concentrate prior to cyanidation (Craw 2003). The concentrate is roasted in an...

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Macraes MiningLink - The largest most visited mining ...

Ore from the Macraes operation is processed at the adjacent gold processing plant that incorporates a pressure oxidation plant to processes sulphide ore. This plant is one of only three other such plants in the southern hemisphere. Ore coming into the Macraes gold processing plant is subjected to being crushed, a grinding flotation process, fine grinding, pressure oxidation CIL (carbon-in ...

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Macraes Gold Project: Value Creation through Applied ...

The Macraes Gold Project, operated by GRD Macraes Limited, engaged GRD Minproc Limited to assist with the evaluation of a pressure oxidation circuit, this being the key component of a recovery enhancement project. The initial study gave sufficient confidence in the process to enter into project execution. GRD Macraes Limited was the first company to...

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Recovery enhancement at Macraes Gold Project: the choice ...

Recovery enhancement at Macraes Gold Project: the choice of pressure oxidation Author La Brooy, S.R., Cadzow, M.D. Australian Symposium on Recovery of refractory Gold

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Geochemical changes in mine tailings during a transition ...

2003-08-01  The Macraes gold mine, in southern New Zealand, was developed in a low grade mesothermal deposit. A pressure–oxidation plant was commissioned in 1999 to oxidize pyrite and arsenopyrite in the ore and release gold from within the sulphide grains. Pressure–oxidation discharges include anhydrite, jarosite, and amorphous Fe arsenates with molar Fe/As of 2–7 and up to 0.5 mol%

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Mining, Processing and Environment at Macraes SpringerLink

2016-08-11  Introduction of pressure oxidation processing before cyanidation has increased gold recovery. Pressure oxidation residues include ferric iron oxyhydroxide, jarosite, and iron arsenate, and associated waters have very high dissolved As. Dissolved As concentrations decrease by 6 orders of magnitude through the tailings impoundment system, via adsorption to iron oxyhydroxides and

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Major Mines Projects Macraes Mine

The Macraes Process Plant recovers gold by concentrating the metal into a relatively small fraction of flotation concentrate, oxidising the reground concentrate in a pressure oxidation autoclave, washing the oxidised residue and then utilising a carbon-in-leach process to recover gold from the residue. In detail the plant comprises:

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PRESSURE OXIDATION OF REFRACTORY GOLD ORES: THE

Pressure Oxidation Pressure oxidation is employed to liberate gold and silver in refractory sulfide concentrates often and ores. The main pressure oxidation products from iron sulfide minerals are sulfuric acid (and metal sulfates) and hematite. Depending on the conditions within the autoclave, acid containing iron compounds can be formed.

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Pressure oxidation - Wikipedia

Pressure Oxidation is a process for extracting gold from refractory ore. The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them. Refractory ores require pre-treatment before the gold can be adequately extracted.

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Geological controls on refractory ore in an orogenic gold ...

2005-03-17  The Macraes mine is hosted in an orogenic (mesothermal) gold deposit in metasedimentary rocks of the Otago Schist belt. Much gold occurs within altered schist with minimal silica-addition, and this study focuses on altered schist ore types. The unmineralized host schists are chemically and mineralogically uniform in composition, but include two end-member rock types:

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Pressure Oxidation - Caldera Engineering

Pressure Oxidation (POX) is a process used to extract gold, copper, zinc, molybdenum, and uranium from refractory ore bodies. The POX process utilizes elevated temperatures (roughly 230 degrees Celsius), elevated pressures (roughly 35 bar or 510 psi), and oxygen to liberate the minerals from refractory ores. POX has been used since 1985 when it was first put into commercial production at ...

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Pressure Oxidation SGS

Pressure oxidation (POX), high pressure oxidation (HiPOX) and ACTIVOX autoclave leaching are viable industry-standard technologies used to recover gold and other accessory metals. The process is particularly well suited for treating refractory gold ores, which

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Geochemical changes in mine tailings during a transition ...

2003-08-01  The Macraes gold mine, in southern New Zealand, was developed in a low grade mesothermal deposit. A pressure–oxidation plant was commissioned in 1999 to oxidize pyrite and arsenopyrite in the ore and release gold from within the sulphide grains. Pressure–oxidation discharges include anhydrite, jarosite, and amorphous Fe arsenates with molar Fe/As of 2–7 and up to 0.5 mol%

More

Pressure-oxidation autoclave as an analogue for acid ...

Gold extraction at the Macraes gold mine in New Zealand involves concentration of pyrite and arsenopyrite, oxidation of those sulphides, then cyanidation. The ore concentrate is predominantly Otago Schist host rock (andesitic composition) with up to 15% sulphides. The oxidation step is conducted on ore concentrate slurry in an autoclave at 225°C and 3,800 kPa oxygen gas pressure with ...

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Macraes Gold Tungsten Project - CPC Engineering

CPC won the contract to complete the metallurgy and process plant component of a feasibility study for the Macraes Gold Tungsten Project for OceanaGold Corporation. The study consisted of a 3.0 Mtpy gold plant consisting of relocating the existing Pressure Oxidation circuit and all new additional equipment as well as a PFS level study into a 1.0 Mt/y tungsten concentrate plant to process high ...

More

Macraes MiningLink - The largest most visited mining ...

Ore from the Macraes operation is processed at the adjacent gold processing plant that incorporates a pressure oxidation plant to processes sulphide ore. This plant is one of only three other such plants in the southern hemisphere. Ore coming into the Macraes gold processing plant is subjected to being crushed, a grinding flotation process, fine grinding, pressure oxidation CIL (carbon-in ...

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Macraes gold mine, Department of Geology, University of ...

Geochemical changes in mine tailings during a transition to pressure–oxidation process discharge, Macraes Mine, New Zealand, J Geochem Expl, 80: 81-94 Petrie, B S, Craw, D, Ryan, C G, 2005. Geological controls on refractory ore in an orogenic gold deposit, Macraes mine, New Zealand, Mineralium Deposita, (in press).

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Material Information Summary - OceanaGold

Recovery of gold at the MGP is achieved through crushing, grinding, sulphide floatation, pressure oxidation (POX) sulphides and a standard Carbon In Leach (CIL). The plant has an established skilled workforce and management team in place.

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Pressure oxidation of double refractory raw materials in ...

Pressure oxidation allows to carry out the efficient processing of goldbearing sulfide materials. However, application of this method for processing of double refractory raw materials leads to irreversible gold losses due to autoclave preg-robbing of gold by organic carbon. Thermodynamic and experimental data indicate that almost complete sulfide decomposition leads to a high value of ...

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Macraes mine to celebrate 25 years - NZResources

Fogarty’s lieutenant was number cruncher Patrick O’Connor who helped steer Macraes to utilise the pressure oxidation process (POX) for treating complex ores. The plant built at Macraes dramatically improved gold recovery and thus the profit line.

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Pressure Oxidation - Caldera Engineering

Pressure Oxidation (POX) is a process used to extract gold, copper, zinc, molybdenum, and uranium from refractory ore bodies. The POX process utilizes elevated temperatures (roughly 230 degrees Celsius), elevated pressures (roughly 35 bar or 510 psi), and oxygen to

More

Pressure Oxidation SGS

Pressure oxidation (POX), high pressure oxidation (HiPOX) and ACTIVOX autoclave leaching are viable industry-standard technologies used to recover gold and other accessory metals. The process is particularly well suited for treating refractory gold ores, which

More

Pressure-oxidation autoclave as an analogue for acid ...

Gold extraction at the Macraes gold mine in New Zealand involves concentration of pyrite and arsenopyrite, oxidation of those sulphides, then cyanidation. The ore concentrate is predominantly Otago Schist host rock (andesitic composition) with up to 15% sulphides. The oxidation step is conducted on ore concentrate slurry in an autoclave at 225°C and 3,800 kPa oxygen gas pressure with ...

More

Mine Details MiningLink.au

Macraes ore Processed at Nearby Gold Processing Plant Ore from the Macraes operation is processed at the adjacent gold processing plant that incorporates a pressure oxidation plant to processes sulphide ore. This plant is one of only three other such plants in the southern hemisphere. Ore coming into the Macraes gold processing plant is subjected to being crushed, a grinding flotation process ...

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MACRAES EXTREME MAKEOVER - OceanaGold Employee

The autoclave is a pressure oxidation vessel used to unlock the refractory gold particles locked within sulphide minerals before the cyanide leaching process begins. What would take place over millions of years of natural weathering to break free the gold, occurs within 30 minutes inside the autoclave.

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Macraes Operation - ASX

2015-03-16  Macraes and Reefton were prepared by, or under the supervision of, K Madambi. C. Bautista is Exploration Manager for the Philippines. M. Holmes, S. Doyle, K. Madambi, and J. G. Moore are Members and Chartered professionals with the Australasian Institute of Mining and Metallurgy and each is a “qualified person” for the purposes of NI 43-101.. C. Bautista is a member of the AIG and is a ...

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Pressure oxidation of double refractory raw materials in ...

Pressure oxidation allows to carry out the efficient processing of goldbearing sulfide materials. However, application of this method for processing of double refractory raw materials leads to irreversible gold losses due to autoclave preg-robbing of gold by organic carbon. Thermodynamic and experimental data indicate that almost complete sulfide decomposition leads to a high value of ...

More

Gold Mining Companies That Use Pressure Oxidation Plants

Macraes ore processed at nearby gold processing plant ore from the macraes operation is processed at the adjacent gold processing plant that incorporates a pressure oxidation plant to processes sulphide ore this plant is one of only three other such plants in the southern hemisphere . Welcome to our hotel! [email protected] Home; About Us; Products; Solutions; Contact; Gold Mining Companies ...

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Pressure Oxidation - Caldera Engineering

Pressure Oxidation (POX) is a process used to extract gold, copper, zinc, molybdenum, and uranium from refractory ore bodies. The POX process utilizes elevated temperatures (roughly 230 degrees Celsius), elevated pressures (roughly 35 bar or 510 psi), and oxygen to liberate the minerals from refractory ores. POX has been used since 1985 when it was first put into commercial production at ...

More

pressure oxidation gold mining process

2019-11-13  pressure oxidation - caldera engineeringpressure oxidation (pox) is a process used to extract gold, copper, zinc, molybdenum, and uranium from refractory ore bodies.pressure oxidation - wikipediapressure oxidation is a process for extracting gold from refractory ore. the most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that.energy requirements for the pressure ...

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What is PRESSURE OXIDATION? What does PRESSURE OXIDATION ...

2017-08-21  theaudiopedia What is PRESSURE OXIDATION? What does PRESSURE OXIDATION mean? PRESSURE OXIDATION meaning - PRESSURE OXIDATION defini...

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Pressure Oxidation Circuit

Table of ContentsPartial OxidationOxygen UtilizationAutoclave Operating ConditionsLime/NeutralizationCyanide ConsumptionDissolved Oxygen in CILElectric Solution ...

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