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Mineral uses in Paint and their Effect on Quality
Table of ContentsThe Uses of Minerals in PaintEffects of Mineral Properties on Paint PerformanceAchieving Improved Mineral Quality for Paint ProductionEnvironmental IssuesFuture Trends in Mineral Use in Paint Although paint is often considered to be a relatively simple commodity, it is in fact a complex composite material. Considerable effort is required to design a coating which is easily manufactured, applies easily
Acid Alcohol Leaching of Apatite
Table of ContentsAqueous Sulfuric Acid DissolutionAcid-Alcohol DissolutionDissolution Reaction KineticsDiffusion Reaction KineticsCombined Reaction and Diffusion Kinetics ModelPreparation and Description of SampleEquipment and ProceduresResults and DiscussionConclusions and Recommendations The current practice for the production of wet-process phosphoric acid (H3PO4) involves leaching beneficiated phosphate rock in the presence of aqueous sulfuric acid (H2SO4). Typical processing involves mining the ore and beneficiating through sizing
Flocculant Dilution System in Thickener Feed well
In order to maximise the benefits obtained from flocculating agents when used as settling aids in high rate and conventional thickeners, it is often necessary to dilute the thickener feed prior to flocculant addition. In some cases, no flocculation at all is possible unless dilution water is used. The most common method of diluting thickener feed has been to recirculate
How Fine Coal Filter Cake is Affected by Copper Ions Addition
Table of ContentsExperimental ProcedureResults and DiscussionInfluence of Copper Ions on Fine Coal Filter Cake Parameters The yield of most types of dewatering installation has been shown to be related to cake specific resistance. Any sludge conditioner which significantly reduces the specific resistance will have a marked effect on the yield, and hence the size of the dewatering equipment required. Results
Upgrading Tantalum Concentrates
Table of ContentsSample DescriptionField StrengthMultiple Pass SeparationEffect of Particle SizeMethods of SeparationApplication of Results The McAllister Ta-Sn deposit, located in Coosa County, Alabama, consists of a series of complex pegmatite dikes and pipes which intrude a granite pluton formation. Wodginite ((Ta, Nb, Sn, Mn, Fe)16O32) is the primary tantalum mineral. The deposit was discovered in 1982 by Callahan Mining Corporation,
Mining Equipment: Select, Buy & Maintain
Table of ContentsMining Equipment SelectionMining Equipment PurchaseMining Equipment Operation & MaintenanceVibration AnalysisOil AnalysisReplacementLooking Ahead Mining Equipment Selection Some basic parameters had to be defined at the time: Mechanical or diesel electric trucks. Number of shovels versus size versus number of pits in operation. Size (height and width) of shops and doors. Number of repair bays. Cranes capacity. Number of service
Wet Screening
Table of ContentsCrusher Slurry Transport SystemsSecondary Wet ScreeningConcentrator slurry systems Immediately after operations commenced in 1972, Freeport experienced a crusher availability that was less than 50%. It was obvious that a change needed to be made. Primary wet screening was selected to remove the fines which caused plugging of the secondary and tertiary crushers and blinding of the tertiary screens
Zinc Column Design
Figure 1 shows the flowsheet for the conventional flotation circuit at Ozark-Mahoning. The plant processes 24.5 mt of ore/hr (27 st/hr) with an average particle size of 60 percent less than 45 µm (325 mesh). Pilot Testing Apparatus and Procedure The controller input was a signal from a level sensor that measures the slurry/froth interface. The controller then adjusted the
Paste Backfill Fundamentals
Table of ContentsPreparation of Paste MixturesPaste Mix Specifications and DesignAdvantages of Paste Backfill SystemsApplications – Case HistoriesLucky Friday mine – Idaho, USABad Grund Mine – Germany Paste is a high density mixture of water and fine solid particles with a relatively low water content (10-25%) such that the mixture has a consistency as measured by the ASTM slump cone test
Selective Flocculation of Zinc Concentrate to Reduce Silica Contamination
Table of ContentsExperimental Equipment and MaterialsResults and Discussion Selective flocculation was used to produce superclean zinc concentrate with minimized silica contamination. Research was carried out on a flotation concentrate from the Jersey Miniere Zinc Company (JMZ) in Gordonsville, Tennessee. The material was first dispersed with sodium silicate and then causticized tapioca starch was used to selectively flocculate the sphalerite, leaving
Dragline Mining & Reclamation Mining
The unique application of a large walking dragline in the mountains of southern West Virginia was developed and implemented by Hobet Mining, Inc. Hobet is an independent operating subsidiary of Ashland Coal and is headquartered at the No. 21 Mine in Boone County, West Virginia, near Danville. Hobet also operates the 07 Mine located in Logan County, West Virginia, near
Puerto Rico Mining & Precious Metal Mineralization
Table of ContentsRegional GeologyGeology of Puerto RicoPrecious Metal OccurrencesPotential for Mining Mining has never been a major source of income for Puerto Rico. The Spaniards mined gold placer deposits during 1509-1579, and extracted an estimated 1,200,000 troy ounces of gold. However, economics at the time discouraged further mining, and richer sources of gold and silver had been found elsewhere in
Sample Preparation Method for Cyanide Shake Assay of Gold
A series of tests were undertaken for the Aurora Partnership-Aurora Project to solve inter-laboratory variations in the analyses of blast hole cuttings. Initial concern was centered on the probability that free gold occurrence was resulting in erratic results for the mine’s cyanide shake assays and outside laboratory fire assays. Test Procedure A 50 kilogram bulk sample of the Aurora belt
Leaching & Recovery of Phosphoric Acid Gallium & Silver
Table of ContentsAcid LeachingGallium Solvent Extraction Treater Dust is the name given to the material that is collected in electrostatic precipitators used for off-gas cleaning of elemental phosphorus furnaces. Elemental phosphorus is made by reacting phosphate ore, silica, and coke in an electric furnace, as shown by these reactions: 2Ca3(PO4)2 + 6SiO2 → P4O10 + 6CaSi03 P4O10 + 10C → P4 +
Drag & Hoist Ropes of Dragline Performance
Typical dragline rigging includes several sets of ropes: hoist ropes, drag ropes, dump ropes and boom suspension ropes. The drag and hoist ropes contribute most to the dragline operating cost, and significantly influence dragline productive time. Both work in very difficult conditions and wear out rapidly. As a result frequent rope changes are required at a substantial cost and time
What are the Effect of Sample Storage on Kinetics of Pyrite Oxidation
Table of ContentsMaterials and Experimental MethodsResults and Discussion Pyrite oxidation has been studied extensively in relation to its role in sulfide mineral flotation. Although pyrite usually lacks economic value in polymetallic ores, it generally acts as an undesirable constituent which complicates the separation of valuable minerals. This mineral is also considered to be the main source of acid mine drainage.
Synthetic Serpentinite
Serpentinite minerals are available in large quantities from asbestos mining activity. The granular or fibrous serpentite, at temperatures greater than 700°C, will recrystalize into olivine, forsterite and enstatite. These minerals have been used and studied for decades and are environmentally safe. The thermal process changes the composition and properties of the original mineral. Therefore, the substitution of the original mineral
How to Separate Zinc Cobalt & Nickel by Solvent Extraction SX EW
An acid mine drainage sludge sample containing 3.6% Mn, 0.18% Ni, 0.15% Co and 0.39 % Zn was obtained from the central part of West Virginia and leached with sulfuric acid at pH 3 and at room temperature. Air was bubbled through the leach solution to precipitate the iron content from the solution at pH 4.5. The leach solution contained
The effect of Dense Media Properties on the Performance of a Dense Medium Cyclone
Table of ContentsMaterial and ExperimentalResults and Discussion The effect of the stability and rheological properties of magnetite dense medium on the separation performance of a 6″ dense medium cyclone (DMC) is studied with the use of fine density tracers. The tests in which different size fractions of magnetite are used to prepare the dense media reveal that at low medium
Kaolin Filter Aids
Efficient filtration of fine kaolin particles plays a crucial role in processing of raw kaolin to a marketable product. Oftentimes, filtration is the rate controlling step of the whole process. As a consequence, plant production is dependent, to a great extent, on the rates being achieved in filtration.. Variation in particle size, coupled with varying amounts of impurities, present several
Low Temperature Pressure Oxidation
Aqueous pressure oxidation at low temperature, although desirable from a process engineering and operations point of view, presents unique problems when temperatures approach 160°C (320°F). In developing the pressure oxidation process for the Lone Tree Mine, elemental sulfur formation and agglomeration with pyrite proved to be a problem. The Lone Tree Mine currently operates a 1.36 million mt/yr (1.5 million
Refractory Gold Ore Flash Roasting
Roasting of refractory gold ores has the primary goal of oxidizing sulfides and organics to improve gold recoveries prior to leaching. Commercial installations currently utilize bubbling and circulating fluidized beds. The principle of flash roasting is aimed at a more cost effective method of whole ore roasting for large throughput applications. Results of pilot plant testing and scale up to
Testing Refractory Gold Ore
Table of ContentsRefractory Ore TypesRefractory Ore Pretreatment ProcessesRanking studiesProcess Selection Process Gold in primary deposits is generally recovered by dissolution in dilute cyanide solution followed by recovery from solution using zinc cementation or carbon adsorption. The dissolution step can be conducted in heaps, vats, or agitated tanks. Gravity concentration, or an intermediate flotation step is an additional process at some
Ink Flotation from Paper Pulps
Increased recycling of waste paper has been emphasized in recent years in both the USA and Canada for environmental and economic reasons. Removal of ink particles from the waste paper pulp is therefore necessary. One of the most promising methods for ink removal is froth flotation. Our study investigated the feasibility of a simplified flotation scheme which showed that about