Blogs

How to Calculate pH without a pH meter

Without a meter, acidity or alkalinity determinations of water for and solutions used in plants treating gold and silver ores are of importance. Methods range from simple tests with litmus papers or phenolphthale in solutions to pH determinations. pH Determination The pH value indicates with a high degree of accuracy the amount of active acidity or alkalinity in contrast to

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How to Sample Gold Ore

The value of any series of experiments depends entirely upon the kind of sample of ore provided for the test. It must represent, wholly and completely, the character of the material that will be treated in the plant to be designed and constructed. If it does not, the tests will be useless or, worse, misleading. In some cases, owing to conditions

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How to use a Microscope to Help Solve Gold Metallurgy

Table of ContentsTypical Gold Metallurgy ProblemsGOLD SAMPLE SURFACE CONTAMINATION The assistance that can be obtained from the microscope in solving ore-dressing problems has been increasingly appreciated in the recent years, as attested by the frequency of papers on the subject. Observations by means of binocular microscopes with magnifications up to 100 diameters and corresponding resolutions have long been common practice, and such

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Sampling Conveyor Belt for Crusher Circuit Survey

Let’s review the steps to collect a sample of coarse rocks such as primary Crusher product. The procedure requires that Process Equipment be shut down and so it is important to organize the work to minimize lost time. First the particular conveyor where the sample is to be collected is identified, next, one to two drums are placed near the

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Flotation Tests with Homemade Flotation Equipment DIY

Table of ContentsFILM-FLOTATIONMECHANICAL FROTHINGTHE SLIDE MACHINESEPARATORY FUNNELSPNEUMATIC FLOTATIONLABORATORY MANIPULATIONSDISPOSAL OF THE FROTHGENERAL CONSIDERATIONS By modelling the basic flotation equipment from the early 1900’s you see that most can hobby prospectors can build or assemble basic froth flotation equipment using all the machines and concepts explained below and perform home-based flotation tests. Although the subject of testing for flotation has been

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Flotation Residue Disposal

Table of ContentsDRAINING AND DEWATERINGFILTERING IN VATSCOMBINATION OF DRAINAGE-BELT AND THICKENERSCOMBINATION OF CONES, DRAINING-BELT, AND THICKENERSCOMBINATION OF CLASSIFIERS AND THICKENERSHANDLING OF DRAINED PRODUCTSINCLINED CONVEYOR-BELTS AND BOOM-STACKERSAERIAL TRAMSHANDLING OF SLIME There are many methods of handling sand and slime from metallurgical operations, but in this article the draining and conveying of waste products from flotation processes will be specially dealt with,

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Analytical Methods for Total Cyanide Assay Determination

SCOPE AND APPLICATION The method is designed to determine the concentration of total cyanide in aqueous/water and soil/sediment samples taken from hazardous waste sites. SUMMARY OF METHOD Aqueous/Water and Soil/Sediment The cyanide as hydrocyanic acid (HCN) is released from cyanide complexes by means of a reflux-distillation, using either a midi- or micro-distillation process, and absorbed in a scrubber containing sodium

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Assaying for Cyanide

Table of ContentsMethods for the determination of cyanideCOMPOSITION OF SILVER-PLATING SOLUTIONSANALYTICAL METHODS1. CYANIDE A. ALKALI CYANIDEFREE CYANIDETOTAL CYANIDETOTAL EFFECTIVE CYANIDESILVERSEPARATION FROM THE CYANIDEDETERMINATION OF SILVERCOMPARISON OF METHODSCARBONATEBARIUM CARBONATE METHODTITRATION AFTER ADDITION OF SILVER NITRATECHLORIDEIRON, COPPER, AND MERCURYAMMONIARECOMMENDED Assay PROCEDURESFREE CYANIDETOTAL CYANIDETOTAL EFFECTIVE CYANIDE (EXCLUDING FERROCYANIDE)SILVERCARBONATECHLORIDEIRON, COPPER, AND MERCURYIRONCOPPERMERCURYAMMONIA Methods for the analysis of cyanide silver-plating solutions were studied, including the

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FREE Cyanide Assay Method

A simple example of the application of a complexation reaction to a titration procedure is the titration of cyanides with silver nitrate solution. When a solution of silver nitrate is added to a solution containing cyanide ions (e.g. an alkali cyanide) a white precipitate is formed when the two liquids first come into contact with one another, but on stirring

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How to Collect a Sample for Cyanide Analysis

It is important to make use of composite sampling and to take at least five samples. Grab samples may be representative of flow during a short period and any other sample shown to be representative of waters being sampled may be applicable. The collection of samples for cyanide determination will require treatment to preserve the constituents. Procedures such as those

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Cyanide Assay Methods

Summary of CN Analysis Methods Description Name Method Description Potential Interferences Measurement Free Cyanide ASTM D 4282 Passive Diffusion at pH 6 and room temperature •     Storage •     Measurement •     Manual chlorination of cyanide with chloramine-T and subsequent reaction with pyridine-barbituric acid. •     Maximum absorbance is determined by manual colorimetry. ASTM D 7237 Flow Injection Analysis (FIA) into a reagent

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Cyanide in Nature

Carbon and nitrogen, the two elements that make up cyanide, are present all around us. Together they make up almost 80% of the air we breathe, and both are present in the organic molecules that are the basis of all life forms. Hydrogen cyanide was formed in the earliest stages of the development of our planet as a precursor to amino acids, from which

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Hydrogen Peroxide Cyanide Destruction Plant

Hydrogen peroxide (H2O2) oxidizes free and weakly-complexed cyanide in a one-step reaction to yield cyanate. Metals such as copper are precipitated simultaneously as hydroxides. CN- + H2O2 → OCN- + H2O………………………………………………………….(1) 2 Cu(CN)3²- + 7H2O2 + 2OH- → 6OCN- + 2Cu(OH)2 + 6H2O…………………………………..(2) The strongest metal-cyanide complexes commonly encountered in the effluents from gold and silver leaching operations are those

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Equipment Sizing: Crusher or Grinding Mill

Table of ContentsSizing a Ball or Rod MillSizing a Crusher using >1200 Wi of Ores from DatabaseHow to Find the Work Index (Wi)How to Find the Work Input (W)How to Correct Calculated Work Indexes for Unnatural FeedsHow to Find Impact Crushing Strength From the Work IndexHow to Find Work Index From Closed Circuit Grindability TestsHow to Find Work Index From

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7 Rare Earth Elements that Run our World {Infographic}

SOURCES Alonso, E et al. 2012. Evaluating Rare Earth Element Availability: A Case with Revolutionary Demand from Clean Technologies. Environmental Science & Technology. 46 (3406−3414) PubMed.gov Humphries, M. 2013 Rare Earth Elements: The Global Supply Chain. Congressional Research Service fas.org King, H. Rare Earth Elements and their Uses. geology.com Mineral Commodity Summaries. 2016. United States Geological Survey. minerals.usgs.gov Rare Earth

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Cyanide Destruction Methods and Processes

Table of ContentsAlkaline ChlorinationINCO SO2/AirHydrogen PeroxideFerrous SulfateCaro’s AcidOzonationElectrolytic OxidationBiodegradationNaCN Detox Experts Detoxification processes are used to reduce the concentrations of toxic constituents in tailings streams and process solutions, either by dilution, removal, or conversion to a less toxic chemical form (sometimes referred to as“destruction” or “degradation” in the case of toxic cyanide species). The objective is to produce an effluent that meets limits

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Pumps & Pumping Research

Horizontal Process Pumps Modification to Comply With API-610 Sixth Edition Forces And Moments Diamond like Carbon Coatings Tribological Possibilities and Limitations in Applications on Sintered Silicon Carbide Bearing and Seal Faces Changes in Pump Vibration Levels Caused by the Misalignment of Different Style Couplings High Pressure Noncontacting Mechanical Seal for API Applications A Case History Improved Hydraulic Design Lowers Cavitation

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Pumps & Pumping Education

Improved Mechanical Seal For High Pressure Pumps in Severe Abrasive Tailings Services Zero Emission Solutions for Mechanical Seals on Light Hydrocarbons Pressure Ratings of Mechanical Seals The Control of Variable Speed Pumps in Parallel Operation An Overview of Hardfaced Coatings for Industrial Use Development of a Noncontacting Seal for Gas Liquid Applications Using Wavy Face Technology Severe Suction Bell Damage

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Ore, Rock & Aggregate Screening (Complete Guide)

Table of ContentsA-Z Guide to Screening Ore, Rock & AggregateVibratory Screen TerminologyEvaluation of the screening purityEffect on screening of the particle distribution of the feedEffect on screening  of the chosen screen hole sizeScreen Undersize and Oversize proportionFactors effecting screeningEFFECT OF CHARACTERISTICS OF MATERIAL ON SCREENINGEffect of oversize proportion on screeningEffect on screening of half size proportionEffect of material weight on screeningEffect of particle

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Falcon & Knelson Concentrators Compared

Read these papers and try to Compare Falcon & Knelson Concentrators only to find out; they perform the same. Both use high gravity centrifugal forces to separate gold from ore with similar results. Do no be fooled by the propaganda. The laws of gravity apply to everyone whether you believe in them or not.

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See-saw Crusher

The See-Saw Crusher is made of a very heavy stone or steel ‘see-saw’ crushers are rolled over the material which is to be crushed with the aid of a lever arm. The material is placed on a flat stone or steel surface and the product is similar to that from a roller crusher.

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Ball Casting Machine

This machine is designed especially to make cast steel balls, utilizing the newly patented Payne hot top principle. This machine will produce solid cast alloy steel balls equal in quality to the best forged steel balls, at a very low cost. The Ball Casting Machine consists essentially of a rotary turntable and thirty-six copper ball molds, the inner half of

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