ABOUT

Solutions & Cases

Our Case
  • Refractory Gold Ore Treatment Methods

    14/07/2016· The process consists of ultraline grinding of ore or concentrate followed by oxidative leaching at atmospheric pressure in agitated tanks. The leach residue is then processed via conventional CIP. The key control parameters arc the particle size

  • The Leachox™ Refractory Gold Process The Testing, Design

    Often when gold is locked in sulphides and silicates it is necessary to reduce the particle size to a size where gold is liberated or partially liberated. For refractory ores this generally translates into grinding below 10 microns and often to as low as 3-4 microns.

  • Refractory Gold SGS

    Also, grinding the ore to an extremely fine particle size can liberate gold encapulsated in sulfides. SGS has very extensive experience with all the unit operations involved in the processing of refractory gold ores, and in selecting the optimum flowsheet for a particular ore. Our gold metallurgy expertise is

  • Ultrafine Grinding an overview ScienceDirect Topics

    The term “refractory ore” is used to classify different gold ores that are not amenable to the traditional cyanidation processes. Gold in refractory sulfide ores occurs as fine inclusions or in solid solution typically within pyrite, marcasite, and arsenopyrite grains.

  • Refractory and Non-Refractory Ore Gold Companies

    In general, refractory ore is one that is not amenable to gold extraction using cyanide. Refractory ore is undesirable because the methods needed to enable gold extraction are expensive. Non-refractory ore is where cyanide can be used to extract the gold. This is

  • Processing of refractory gold ores ScienceDirect

    01/01/1991· In 1029 1030 K.S. FRASER et al. the simplest of terms, a refractory ore is one where gold recovery by cyanidation alone is well below normally accepted levels. One definition, although somewhat arbitrary, has defined a refractory ore as one where gold recovery is

  • (PDF) Evaluation of physical and chemical pre-treatment

    Ultra-fine grinding (UFG) was proposed as a pre-treatment method prior to cyanide leaching of old plant tailings of a refractory silver ore. Direct cyanidation of the as-received tailings (d80

  • Processing Refractory Gold Hydrometallurgy: Leaching in

    Refractory ores are normally have either a high sulfide content that masks the gold preventing cyanide leaching of the gold, or high organic content that also block gold leaching (reabsorbs the gold), or it can have a high clay content that also soaks up the cyanide.

  • (PDF) A Preliminary Study on Nitric Acid Pre-treatment of

    The nitric acid pre-treatment experiments for refractory silver ore and gold/silver concentrate were performed for 2.5 hours at 5M HNO 3 and 80 o C. Before and after nitric acid pretreatment,...

  • Ultra fine grinding of silver plant tailings of refractory

    grinding the ore down to −75 μm. These ores need a suitable pretreatment to achieve high gold and silver extractions rates during cyanidation [1]. Roasting [2], pressure oxidation [3], biooxidation [4,5] and ultra fine grinding [6] have been commercially practiced to enhance the

  • Mixed Media Grinding A Refractory Gold Case Study

    That is, whilst employing inert grinding media during secondary grinding, electrochemically active forged steel grinding media may be used in the primary grinding stage. This paper discusses the impact of such a circuit on the pulp chemistry and flotation response of a refractory gold ore. The Wiluna concentrator has two grinding circuits operating in parallel. Line 1 operates a single ball mill in closed circuit with

  • Ultrafine Grinding an overview ScienceDirect Topics

    The term “refractory ore” is used to classify different gold ores that are not amenable to the traditional cyanidation processes. Gold in refractory sulfide ores occurs as fine inclusions or in solid solution typically within pyrite, marcasite, and arsenopyrite grains. In this type of ore, because the gold is encapsulated, the interaction with cyanide to form the soluble metal complex is inhibited

  • Refractory gold reserves: Challenges and opportunities for

    23/03/2021· Refractory gold reserves, which require more sophisticated treatment methods in order to achieve oxide-ore recovery rates, correspond to 24 percent of current gold reserves and 22 percent of gold resources worldwide (Exhibit 1). Despite offering a higher grade, these ores can only be processed using specific pretreatment methods such as ultrafine grinding, bio oxidation, roasting, or pressure

  • (PDF) Improvement of Cyanidation of Antimonial

    The ultrafine grinding of the refractory Akoluk ore was shown to improve the cyanide leaching of gold and silver, only to a limited extent i.e. by 26% and 18% improvements for gold and silver extractions, respectively. Despite these improvements, the highest extractions were recorded to be 66% Au and 26% Ag, which were achieved at the finest size tested (d80: -3.7 µm). Further treatment of the ore by a

  • Processing of refractory gold ores ScienceDirect

    01/01/1991· In 1029 1030 K.S. FRASER et al. the simplest of terms, a refractory ore is one where gold recovery by cyanidation alone is well below normally accepted levels. One definition, although somewhat arbitrary, has defined a refractory ore as one where gold recovery is less than 80% after conventional cyanidation. In whatever way a refractory ore is defined, economic methods must be found to improve

  • Processing Refractory Gold Hydrometallurgy: Leaching in

    The term 'refractory' has become a name that is commonly applied to ores that are more challenging to treat economically. Typically referring to gold deposits. Any ore can be treated by methods that will generate high recovery, but the part that we are all challenged by is achieving this with a positive economic outcome.

  • (PDF) Application of Diagnostic Leaching Technique for

    Ultrafine grinding, modified cyanidation, roasting, pressure oxidation and bacterial oxidation are the pretreatment methods currently practiced for refractory gold ores and concentrates [4,5]. Ultrafine grinding is one method for liberating of locked gold for some ores if efficient size reduction is obtained [6].

  • Gold processing Mining and concentrating Britannica

    Such ores are referred to as refractory, and they frequently contain the sulfide minerals pyrite, pyrrhotite, or arsenopyrite. Gold can be freed from these ores or concentrates by treating them with various oxidizing processes. The most common method is to roast gold-bearing minerals at temperatures of 450° to 750° C (840° to 1,380° F) to destroy the interfering sulfides. Oxidation can also be accomplished by the use of

  • (PDF) A Preliminary Study on Nitric Acid Pre-treatment

    The nitric acid pre-treatment experiments for refractory silver ore and gold/silver concentrate were performed for 2.5 hours at 5M HNO 3 and 80 o C. Before and after nitric acid pretreatment,...