The Method of Gold Processing by Cyanidation

Gold cyanidation processing systems is that many of the basic methods used in processing gold throughout the world. And cyanidation process has been patented in 1887 and was first used in mining
  • Crown Mine, New Zealand in 1889 
  • Robinson Deep, South Africa in 1890 
  • Mercur, the United States in 1891 
  • El Oro, Mexico in 1900 
  • He Belliere, France in 1904
      The function of the cyanidation method is to increase the recovery of gold and silver below 70% to better than 90% because of the gold minerals are encased by silica rocks are smooth and have a low grade that can be directly by the solvent extraction of cyanide. In some ores, particularly those who are most sulfidized, aeration (before the introduction of cyanide) from the ore in water at high pH can make elements such as iron and sulfur are less reactive to cyanide, and therefore the gold cyanidation process more efficient. In particular, oxidation of iron to iron (III) oxide and subsequent precipitation as iron hydroxide to minimize the loss of cyanide from the formation of iron cyanide complexes. Oxidation of sulfur compounds to sulfate ions to avoid the consumption of cyanide byproduct thiocyanate (SCN-).
       Cyanide is a universal solvent in the processing of gold, and solvents commonly used in the processing of gold by cyanidation is NaCN, KCN, Ca (CN) 2 or a mixture of these three parts sianide. However, for solvents that are often used in the treatment process is being able to dissolve gold NaCN better than the other solvents. Cyanide NaCN, KCN, AgCN that is in use in the processing of gold and usually shaped salt crystals are also often used for photographic, metal plating and staining. In the metal plating, acid cyanide used in the cleaning process, hardening and metal plating metal to obtain seeds from the seed of pure gold metal.

READ MORE >>>   Gold Cyanide Method

How To Detect Gold With Metal Detectors

Metal detector is very important for use in a process of finding land that have potential metallic mineral content. Because the metal detector will be able to respond to the presence of a metal or any type conductive or magnetic materials in rocks in the soil. Metal detector is also very useful in the search for gold ore, so by using our metal detector equipment with easy to find a gold metal content. Various types of metal detectors at this time has been widely developed by various manufacturers and some manufacturers of metal detector maker also has characterized the search uses a mineral or metal targets.
      In the use of a detection of gold, a soil condition is affecting the operation of metal detectors is where the heavy minerals and heavy soil conditions will cause the electromagnetic field and result in shrinking the primary weakness of a signal on the metal at depth. And a soil in wet conditions allow greater penetration of the main magnetic field, providing better signal coverage on the basis of soil depth.
These few simple steps that can be used when we will start using a metal detector:
  1. Check the battery condition. Batteries should always be in good shape, so that when in use the metal detector can work well 
  2. Headphones should always be used when starting to use in search of minerals or metals, due to the use of headphones signal will be easier to listen. Some prospectors are also often add a device mounted audio amplifier to amplify small signals, so that small signals can be easily detected and more sensitive in receiving a signal.
  3. Discrimination should always be zero.
  4. Adjusting the audio so that the first tuning of the detector hum barely audible.
  5. Prior to the area of land that will be the detection phase and that we should be easy to distinguish the resulting sound detection devices, detection devices should be the gold we test first, you try to use metallic gold you have and bury in the soil at the depth of 30 cm and you listen noise and signal whether it is correct. And then you try to bury it back a small iron equal depth and listen to sounds and signals. The function of this method is to differentiate and to familiarize us with the sound generated from the detection devices. The resulting audio signal usually varies according to the type of target. Gold tends to produce short signals, signal a sharp metal object while generating broad signal.  
How to detect a metallic gold on a field:

Chemical melting Processing



Quartz  SiO2 Fluxing agent ,
Glass xNa2OyCaOz SiO2 Fluxing agent ,
Borax Na2B4O7 10H2O Fluxing agent ,
Borax Na2B4O7 Fluxing agent ,

Phosphorus Salt
Na ( NH4 )HPO4 4H2O Fluxing agent
Soda Na2CO3 Fluxing agent,

Melting Process Of Gold Ore

Consolidation is a method for obtaining metals from ores or metals. This usually involves the reduction of metal oxides (ore) to metal (reduction reaction are those which take electrons away from the elements, the reduction becomes the opposite of oxidation reactions), and the formation of non-metal oxide waste known as slag. It is a chemical process and involves more than just melting the gold. In the process of smelting gold metallic mineral ore concentrates the results of gold, the melting process is a fire burning at a temperature of 1800 ° C, causing an oxidation of minerals and melt and form a solid system - liquid. And in the process of smelting, the ore minerals may be added by Chemical Fusing Metallic Minerals such as
borax, backing soda, or with ammonium chloride (NH4Cl) to mineral-borne heavy metals along with gold ore minerals can be separated.
At the initial stage of fusion is to place the mineral ore concentrate which was completed in the extraction into a container shaped like a fusion of glass or a large bowl made ​​of carbon materials. Then the container was put into a melting furnace, because the fireplace can help keep a certain chemical conditions and hot temperatures in order to stabilize the mineral ore into a metal melt easily. Metallic mineral ores need to be heated to very high temperatures to produce pure metals as well as temperatures higher temperatures. Iron melts at 1800 ° C (3270 ° F) and gold melts at 1062 ° C (1943 ° F). Because iron has a higher melting temperature than gold. After the melting process was finished and the metal has completely melted as liquid water is clear and shiny metal can then immediately pour into a mold to form an ingot that would be cool if it has a gold metal bars.

Gold Flotation Process

The Basic Principle Flotation Process
In the flotation process of the major steps that must be done include:the process destruction of rock minerals, milling, flotation, drying and smelting : 

The process of destruction of rocks minerals and grinding
In this process of rock minerals that have been taken from the mine site and then destroyed by the machine to obtain a fine grain of sand to free metal-containing granules for further processing. In the destruction of mineral rocks of machine tools can use a stone crusher machine, so the minimum size of rock minerals can reach between 28 mesh

The Process of Flotation 
At this stage after a mineral ore that is refined inserted into the machine agitator tank which is usually also called a flotation cell to produce a pulp slurry concentrate.

In the process of this flotation Reagent Which In Use Is a form of lime, bubble and collectors. Froth forming a bubble that is stable and that float to the surface as a froth flotation cell. Collector reagents react with the surface of the precious metal sulfide mineral particles making the surface is water repellent. surface of the mineral-bound water molecule is released and will be changed to hydrophobic. Thus the collector end of the hydrophobic molecules will be bound hydrophobic molecules from the bubble, so the mineral ore can be adrift. Collector has a molecular structure similar to the detergent hydrophobic sulfide mineral grains are attached to the air bubbles that rise from the slurry zone into the froth that floats on the surface of cells.
 Valuable mineral-laden froth which resembles a metallic detergent foam, and foam concentrate that has been lifted from the drain into the upper lip and into the trough flotation machine is in use as a valuable mineral collection
The Process of Drying and Smelting: 
Valuable minerals that have been collected in the form of concentrates and mineral ore slurry 65% solids by weight in dry with the dryer until the water content there is only 9%. After all selasai dried it is ready for its mineral ore in the smelting process.

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Chemical Reagents On The Flotation Process

Xanth (ogen ) ates Sulfide Flotation
Dithiophosphates Sulfide Flotation   
Carboxylates ( Fatty acids ) Carbonate / Oxide / Sulfide Flotation
Dithiophosphates Sulfide Flotation   
Alkyl ammonium salts Silicate / Oxide Flotation

Aliphatic alcohol ( Methyl isobutyl carbinol ) Frother
Cyclic alcohol ( Pine oil, Eucalyptus oil ) Frother, Collector
Aromatic alcohol (Cresols, Xylenol ) Frother

REGULATOR ( Modifiers ) FUNCTION       
Lime (Dalkeith) Sulfide pH - Depressor phyrite
Sodium hydroxide pH-Disperses gangue
Sulfuric acid pH
Copper Sulfide Sphalerite Activation
Sodium Sulfide Activation /Oxidation
Cyanide Depressor Sulfide
Chromate Depressor Galena

READ MORE >>> Flotation Process Of Gold

Gold Flotation System

         Flotation derived from the word meaning float. Flotation can be interpreted as a separation of a substance from other substances in a liquid or a solution based on differences in surface properties of the substance to be separated, where the substances that remain hydrophilic aqueous phase while hydrophobic substances that are air bubbles will be bound by and will be brought to the surface solution and form bubbles which can then be separated from the liquid, where flotation process aims to separate and produce a metal concentrate. This process produces metals from ore concentrates at the mine by separating valuable minerals from impurities that cover it. This process is said to have been discovered by a miner who see the process of washing machine that is used as a means of washing the dirty work clothes, and the washers that generate bubbles in the foam.
The main step in mineral processing are crushing, grinding ore to a size change the amount of fine sand grains in order to liberate the metal to the separation process and to prepare the appropriate size to the next process. Flotation on the gold metal is very effective if the gold contained in sulfide minerals such as phyrite, other than that this process is often done if the gold ore minerals join copper, zinc or lead. Flotation process is generally not free floating particles of gold but very effective if the gold is associated with sulfide minerals such as pyrite. In a typical pyrytic gold ore, gold formulated in a crystal structure of iron sulfide. Highly oxidized ores generally do not respond well to flotation. Flotation process consists of mineral concentrates produced through the use of chemical conditioning agents followed by intense agitation and Air Sparging of agitated ore slurry to produce mineral-rich foam concentrate.
        Factors affecting the flotation is particle size, pH, surfactant, and other chemicals, such as coagulant. Large particle size makes these particles tend to settle so hard to be able to react in flotation. While high pH particles tend to settle. The function of surfactant is a collector which is the reagents that have polar groups and non polar groups at once. collectors will change the nature of the particles from hydrophilic to hydrophobic. While the addition of coagulant can result in the size of the particles become larger. Another factor affecting the rate of flotation is the air that serves as the binder particles have hydrophobic surface properties, percent solids, for the flotation of coarse particles can be done with a large percent solids and vice versa, a large feed rate which affects the capacity and time to live. The rate of flushing air which serves to drain the concentrate into the lounder. The thickness of the layer of froth and bubble size also affect the flotation.
       The advantage of the flotation process is that gold values ​​are generally released on a fairly coarse particle size (28 mesh) which means that the cost of milling ore minimized. Reagents used to separate generally non-toxic, which means that the cost of tailings disposal is very low