Bioleaching: Introduction Methods Application Copper Microorganisms and Processes! Introduction to Bioleaching: Leaching process was first observed in pumps and pipelines installed in mine pits containing acid water This process was later on employed for recovering metals from ores containing low quantity of the metal Presently certain metals from sulfide ores and other ores are Abstract: Heap biooxidation is the most economic option of treating processing plants tailings and refractory ores containing non-ferrous and precious metals and sulphides Pyrite tailings of copper ore processing (Sample 1) tailings of sulphide copper-nickel ore processing (Sample 2) and double refractory gold-bearing ore (Sample 3) were studied Autotrophic microorganisms Acidithiobacillus

Bacterial Oxidation Technology

Bacterial Oxidation Technology - A Viable Process for Refractory - Free download as PDF File ( pdf) Text File ( txt) or read online for free Bacterial oxidation technology can be applied to refractory sulphide ores and concentrates to break down the mineral matrix and release the precious and base metals The precious metals and some base metals remain in the oxidized residues and can be

Heap biooxidation is the cheapest option to treat processing plants tailings and refractory ores containing non-ferrous and precious metals and sulfides The tailings of copper ore processing (sample #1) the tailings of sulfide coppernickel ore processing (sample #2) and double refractory gold-bearing ore (sample #3) were studied Heap biooxidation tests used the autotrophic microorganisms

Gold which has formed an alloy with other metal forming a solid solution is considered refractory by definition if you can't get recoveries beyond 80% then you can call it a refractory ore whether it's a mineral processing problem or not will depend on the type of refractory I will consider a mineral processing problem those ores which have micro gold particles which cannot be liberated

Thus heap leaching is mainly applied to low-grade ores such as secondary copper sulphides pyritic gold ores or nickel/nickel-copper sulphide ores The hypothetical heap operation in Figure 5 illustrates the application of solution irrigation common to both oxide and sulphide ores and of aeration usually applied to sulphide ores to

FOR GOLD RECOVERY FROM REFRACTORY ORES In this article pre-treatment such as bio-leaching before cyanidation is discussed as an alternative technique to treat refractory gold ores containing pyrite and arsenopyrite There are two methods of bacterial leaching namely stirred reactor bio-leaching and bio-heap leach processes The examples of

sulphide gold ore processing

To complicate matters further these ore bodies are often refractory where the gold is locked within sulphide minerals or double refractory in which gold is locked within sulphide minerals and preg-robbing due to the presence of organic carbon These must be pretreated ahead of leaching

BacTech Enviromet Corp in conjunction with Mintek 14 has developed proprietary technologies for the high temperature leaching of copper concentrates Working in conjunction with Industrias Penoles SA de CV one of Mexico's largest and most diverse mining companies they operated a 2 2-metric tons per day (mt/d) stirred-tank copper-concentrate bioleach demonstration plant in Monterrey

Chlorination leaching of floatation concentrate could be a route for treatment of refractory ores instead of roasting BIOB or POX some companies are also testing fine grinding and oxygen injection using shear reactors in alkaline cyanide systems Direct leaching of ores

1 Introduction Gold ores are considered refractory if gold extractions from a conventional cyanidation process are less than 80% even after fine grinding 1) Arsenic-bearing refractory gold ore has stones extremely difficult to deal with In the stones gold is locked up in arsenic mineral matrix as the form of microscopic or submicroscopic lattice

The present invention relates to the heap leaching of sulphide ores More particularly the present invention relations to the biooxidation of sulphide ores in heaps at least one of such heaps being formed of ore to which a bacterial inoculum has been applied prior to the stacking of the heap

bacterial leaching as a pre-treatment step for the extraction of gold from refractory ores and concentrates offering potentially significant advantages over the conventional oxidative pre-treatment alternatives (Komnitsas and Pooley 1989) Bacterial leaching has been shown in numerous dump and heap leaching situations to be

Bacterial leaching is an established method of treating refractory gold and base metal ores or concentrates SGS Minerals Services has undertaken testing for numerous projects for flowsheet development and optimization including bench scale and pilot plant testing and audits and troubleshooting at operating plants in South Africa Brazil Ghana

Table of ContentsBIOX Plant OperationBIOX Process ImprovementsStability of Precipitates The bacterial oxidation (BIOX) process for the pre-treatment of refractory ores for gold recovery was developed by the Genmin Process Research laboratory Early work started in the late 1950's when the bacteria strain "Thiobacillus ferrooxidans" was isolated from effluents pumped from the West Rand

Processing Gold Ores Using Heap Leach

Bacterial heap leaching of refractory gold/sulphide ores GOLD ORE8 BACTERIAL HEAP LEACH PROCESS FOR GOLD ORES Fig 3 Block Know More Processing Gold Ores Using Heap Leach-Carbon Adsorption Proposed heap leach-carbon adsorption process for gold ores low in silver

Four iron-sulphide-containing gold ores from the White Mountain mine in the Jilin Province China were studied to examine the benefits of using oxidative treatment prior to conventional cyanidation to leach gold This pre-treatment consisted of bubbling air into an ore/water mixture for eight hours while adding enough caustic sodium hydroxide to maintain a pH of 11 throughout the test Three

Extraction of valuable components from sulphide ores using microorganisms is a recognized biotechnological method combining several advantages over traditional methods of mineral processing This paper presents the main factors affecting the bacterial-chemical leaching and methods of leaching with the participation of microorganisms Some physical-chemical (temperature pH oxygen carbon

Heap leaching technology – current state innovations and future directions: (Vaughan 2004) In sulphidic refractory gold ores fine gold particles may be highly disseminated and locked up in sulphide minerals such as pyrite and arsenopyrite (namely the heap leaching of refractory sulphide ore and of uranium ore)

This investigation compares bacterial leaching to chemical leaching to solubilize copper from a copper containing ore of the new site Northern Qarashoshaq in Zhylandy (Kazakhstan) which is currently under commercial development From ICP-OES analysis the bulk ore sample contains 1 5% of Cu and a trace level at 0 0024% of Ag Phase analysis shows the main copper containing minerals are

In this gold sulphide concentrate three main reasons explain most of the variability response found at leaching tests: (i) gold exists as free and non-free particles with sizes of 10 mm to 100 mm (ii) the product has completely roasted particles as well as partially and almost intact sulphides particles and (ii) the granulometric composition of the samples is quite different and gold in

Environmental Effects and Bacterial Strategies for Resistance Bio-oxidation of sulphide contained in refractory gold ores enhances liberation of gold particles Distinct advantages have been reported for bio-leaching of gold over traditional physicochemical methods

23/3/1993A bacterial-assisted heap leach process for the solubilization of a metal from a refractory ore containing said metal and containing fines and/or clay wherein said ore is formed into a heap and at least a portion of said metal in said ore is solubilized by sequential or concomitant bacterial oxidation of sulfides and dissolution of said metal into a leaching solution said bacterial oxidation

The BacTech process for the liberation of gold encapsulated in refractory ores developed by BacTech (Australia) Ltd and used commercially at Gold Mines of Australia Ltd's Youanmi mine 500 km northeast of Perth in the Yilgarn mineral field is based upon work which started in 1984 in the Chemistry Department of King's College London under the supervision of Dr J Barrett