Blogs
Electrowinning of Gold & Silver from Copper Bearing Cyanide Solutions
Table of ContentsExperimentalResultsDiscussion of Results and Conclusions One stage of the cyanide leach process to extract submicron Au particles from disseminated Au ores frequently uses electrolysis. Metals are electrowon from a solution containing Ag, Au, and Cu as cyanide complexes. The electrolyte commonly has Ag and Au concentrations in the 10 to 50 µg/mL range, while Cu, depending on the
Column Flotation BIAS
Table of ContentsCounter Current flow of mineralized bubbles & wash waterCounter Current flow of slurry and air bubblesHydraulic Entrainment Counter Current flow of mineralized bubbles & wash water The column underflow is always of slightly higher volume than the feed. This volume imbalance, called BIAS in the control system, is made up by wash water inserted at the top of the column. Part
Gold Refining Contract
The operator’s relationship with the refinery depends entirely upon a well-defined written contract, good representation at the refinery and the use of reliable assay laboratories. While all contracts are similar in that they are meant to safeguard the interest of both refiner and miner, it is not unusual to find a single refinery writing a variety of contracts, each one
Gallium Uses
Table of ContentsGallium Uses and ConsumptionGallium for Integrated Circuit Applications Gallium: Cominco has been at the interface between the semiconductor materials and the components industries since the commercialization of the transistor in the early fifties. Based on our commitment to R&D, we have become the largest merchant supplier of several specialty semiconductor substrates including LEC-grown semi-insulating gallium arsenide wafers on this
How to Recover Hematite & Chromite Fines by Wet Magnetic Methods
Table of ContentsMagnetic Characteristics of Natural Hematite and ChromiteWet High Intensity and High Gradient Magnetic SeparationsCarrier Magnetic SeparationMagnetic Field-Induced Aggregation Wet magnetic separation methods for recovering hematite and chromite fines and ultrafines are investigated in this paper. These methods include wet high intensity and high gradient magnetic separations, carrier or “piggy-back” magnetic method, magnetic field-induced aggregation and magnetic seeding. This
Ball Mill Circuit Classification System Efficiency
Fines may be defined as any material smaller than a specified product size, and “coarse” as any material that is larger. The target 80 percent passing size of the grinding circuit product is a convenient reference point, as it is often used to express the grind size objective. This size is close to the modal value of typical size distributions
Bioleaching Cadmium Sulfide
Table of ContentsBacteriaBacterial Leaching Experiments The applicability of electrochemical techniques in the elucidation of intermediate reactions in the bacterial oxidation of cadmium sulfide minerals has been demonstrated. Furthermore, it was found that the bio-oxidation process was solid-state diffusion controlled. Greenockite (CdS) and hawleyite (CdS) are the most important cadmium minerals, which occur as minor constituents in ores of zinc, lead
Acid Leaching Copper Flotation Concentrate
Table of ContentsAcknowledgmentsEquipment and MaterialsBatch TestingExperimental ProcedureEvaluation of Operation ProceduresEffect of Mill Rotor SpeedEffects of Solids LoadingKinetics of LeachingContinuous Testing Procedure24 Hour Test12 Hour TestsLiquid-Solid SeparationSolvent Extraction Electrowinning As an alternative to Acid Leaching, Copper Chalcopyrite (CuFeS2) concentrates are processed traditionally by smelting, which results in sulfur dioxide (SO2) emissions. The development of a hydrometallurgical process for recovery of metals from
Large Melting Furnace – City Waste
Table of ContentsLarge Melting Furnace Design CriteriaDescription of Large Melting Furnace & EquipmentFeed HandlingMelterElectric Arc Melting FurnaceFurnace RefractoriesFurnace CoolingPower Supply, Control, and MonitoringSlag Tapping and GranulationFume-Offgas HandlingDucting Heat Exchanger Baghouse and Thermal OxidizerNitrogen Inerting System The most widely applied method for the disposal of waste materials, including sludges, dusts, scales, leachable slags from smelting or melting operations, and residues from
Recover Neodymium from Permanent Scrap Magnet
Develop hydrometallurgical or pyrometallurgical recycling methods to recover valuable rare-earth compounds from various forms of NdFeB magnet scrap. The U.S. Bureau of Mines (USBM) has developed technology to treat and recycle a variety of wastes containing valuable and strategic metals. As part of this effort, the USBM developed a process to separate neodymium and other valuable rare earths from iron
How to Make Graphite Flakes from Steel Waste
Develop a technology for producing high-quality flake graphite from the steelmaking waste known as kish. Approach: Treat the waste kish as an ore and apply mineral processing techniques of physical beneficiation and chemical purification to produce a range of graphite products competitive with the natural mineral. Graphite is a naturally occurring form of carbon with a unique combination of properties that
Primary & Secondary AG Autogenous Grinding
Primary autogenous mill feed is either primary crusher discharge or run of mine ore, containing material on each size of the screen analysis below the largest piece in the feed. It is subject to the large variations in size analysis normally found in primary crusher products or run of mine ore. There can also be variations due to segregation in
How to Measure Grinding Efficiency
The first two Grinding Efficiency Measurement examples are given to show how to calculate Wio and Wioc for single stage ball mills. Figure 1. The first example is a comparison of two parallel mills from a daily operating report. Mill size 5.03m x 6.1m (16.5′ x 20′ with a ID of 16′). This example shows that Mill 2 is slightly
Cone Crusher
Table of ContentsExisting Crusher Application TechniquesNew Design MethodsCone CrushersMedium and Fine Crushing ChamberCone CrushersSymons Cone CrusherStandard Cone Crusher CapacityShort Head Cone Crusher CapacityCone Crusher Components and Operating PrincipleTRAMP IRON & CONE CRUSHERSCone Crusher Short Head VS Standard HeadCone Crushers for SaleCone Crusher Hydraulic System OperationFast & Easy Control Product SizeProtect Cone Crusher from Tramp IronCone Crusher Feed DistributionCrusher FoundationUniform Crusher Discharge ProductCone Crusher Dust Seal Protects
Crushing Finer to Reduce Grinding Cost
This new high energy or power rate crushing brings a different perspective to comminution flow sheet selection. Generally, up until the early 1960’s the classical flow sheet for a beneficiation plant was primary crushing followed by two stages of cone crushing in closed or open circuit, making feed for rod mills, followed by ball mills. The rod mill was needed to
Allis Chalmers Corporation
The Allis-Chalmers Corporation was founded in Milwaukee, Wisconsin, in 1847 as the E. P. Allis Company, which had an initial interest in manufacturing components in the grinding of flour. As such, its roots were started in reducing material size, which is covered by the generic term, comminution. The Corporation evolved by a series of mergers into one of the world’s
Mineral Titles Online MTO BC
Table of ContentsMTO British ColumbiaMineral Claim – Work Requirement in BC Using this summary page you can locate Geological Maps from the MTO Online service in British Columbia to acquire Mineral Titles, Mining Claims. Mineral Title means a claim or lease acquired and maintained under the Mineral Tenure Act and its predecessor Acts (the Mineral Act and the Placer Mining Act)
SAG Mill Components
Once the basic operating conditions have been defined for the mill designer then, and only then, can he begin taking into account shell and head stresses and trunnion bearing sizes required to carry the load and to give the required openings for feeding and discharging the mills. Mill heads are key structural components of any grinding mill. They must carry
Crushing Simulation
In the context of this paper a simulation model for a size reduction device is an equation or equation set which allows the calculation of the product size distribution from the device for a specified size distribution of feed. The model might be expressed as a simple algebraic expression, as a matrix equation, or as a finite difference formulation. The
Laboratory Balling & Pelletizing Method
Early laboratory balling and pelletizing tests resulted in balls or pellets superior in quality as compared to production pellets, no matter what the variable being tested. In order to indicate more closely what a material would do for balling and pelletizing in a plant we felt it was necessary to approach the plant conditions. When the commercial ball size was
Crushing SAG Mill Critical Size Material
Table of ContentsPebble Crusher in Semi Autogenous Grinding Semi autogenous Grinding with Pebble CrusherDesign of the Pebble Crusher Installation The relationship between the grinding power consumption and the product size distribution has been widely studied since it is a subject of major interest for plant design and optimization. The conventional approaches, generally of empirical nature, have led to the formation of
Grinding Circuit Process Control
The inferred particle size model is a key part of the grinding control system presently being used. The model, as used during the evaluation period, related the percent +65 mesh material in the cyclone overflow to three of the mill operating variables: ball mill feed, mass flow of ore to the cyclones, and mass flow of water to the cyclones.
Crushing & Grinding Circuit Design – Comminution
The rising costs for and the possibility for limited availability of electrical energy are emphasizing the continual conflict faced in the selection of comminution circuits used in preparing ores for concentration, namely; capital cost vs. operating cost. Frequently, the circuit with the lowest capital cost is not the most efficient in the use of electrical power and wear resistant materials.
AG – Autogenous & SAG Semi-Autogenous Mill Design Calculations
Table of ContentsSAG Mill ChargeSAG Mill Horsepower — Drive PowerOre Testing for AG & SAG Grinding Mill Design Mill Sizing: After laboratory and pilot plant testing confirm the feasibility of autogenous or semi-autogenous grinding, it can be used to establish the exact grinding circuit and mill size. In the pilot plant tests, the tare power of the pilot plant mills should