Blogs
Using Wetlands for the Control of Acid Mine Drainage
Table of ContentsMetal Removal Processes of WetlandsPractical Limitations to the Use of Wetlands for Mine Drainage Control Metal Removal Processes of Wetlands A wetland environment can remove metals from influent waters in a variety of ways. As chemical oxidation takes place, oxides and hydroxides of iron can be expected to precipitate from surface flow, resulting in the characteristic yellow sediment
How to Improved Fine Particle & Bubble Flotation
Table of ContentsSample DescriptionExperimental Procedure and EquipmentTailings AnalysisBubble Size MeasurementsFactorial Experimental DesignResults and Discussion Selective beneficiation of fine particles depends heavily upon the flotation separation process. Conventional froth flotation for many ore systems is very effective for particles between 300 and 20 µm in size, but the flotation efficiency commonly drops off as the particle size decreases below 20 µm.
Methods of Improving Mineral Flotation Circuit Performance
Table of ContentsQuantitative Methods of Describing Flotation Data The Effects of Chemical Reagent Dosage Particle Size Versus Chemical and Equipment Interactions Some Influences on Concentrate Grade and Selectivity The process of froth flotation as a means of upgrading the quality of coal by removing ash/pyrite and of separating selected mineral(s) from undesired gangue materials is certainly one of the most common unit engineering
Chemistry of Mineral Slurry Rheology Control Grinding Aids
Table of ContentsDiscussion of Dispersion Theory of Solids in Aqueous SlurriesSome Results of Screening Appropriate Chemical Reagents Tests run on using organics to influence the fracture strength of solids gave an almost bewildering array of results on the four substrates. Two general classes of tests were carried out: 1) a procedure consisting of introducing a notch in a small rectangular
Flocculation & Lewis Acid-Base Theory
Table of ContentsMethods and MaterialsResults The use of synthetic polymers such as polyacrylamide and its derivatives to dewater mineral-processing waste streams has become commonplace. The use of polymers often solve many of the solid-liquid separation problems encountered by the industry. However, using polyacrylamides to dewater clay containing minerals such as montmorillonite and kaolin often produces a dewatered material containing a
Hydrocyclone Modelling Method
Mineral and chemical industries use the hydrocyclone for size classification as well as solid-liquid separation. The geometry of the device being very simple, a tangential involute section attached to a cylindrical section and a conical section attached to the other end of the cylinder, the device has found widespread use. Majority of the research papers dealing with the modeling of
Agitative Agglomeration
Table of ContentsDisc PelletizerDrumsSpherodizerIron OrePin Agglomerator Agitative agglomeration is the process of the consolidation of particles into larger shapes by means of agitation with a liquid. Most fine powders can readily be formed into granular masses by admixture with a liquid and by utilizing a suitable agitation method. Ideally, each particle should be coated with the liquid by stirring or
Thionocarbamates Collector & Sulfide Flotation & Adsorption
Table of ContentsFTIR and UV SpectrometryMicroflotationIBECTC The mineral processing industry has recently shown an interest in developing new collectors that can be used for selective flotation at lower pH levels. The desired end result is to reduce lime consumption and to improve the efficiency of separation in the treatment of complex and low-grade ores (Nagaraj et al., 1986c). One such
SABC Grinding Circuit
Table of ContentsSABC Test ProceduresSABC Test ResultsStages 1 & 2 – Cut Discharge GratesStage 3 – Cast Pebble Ported GratesBall Mill CapacityScat Discard OptionSABC Circuit OperationSemi Autogenous Ball Mill Crushing Circuit SABCMills RationalizationPilot Plant StudiesConstruction and Start Up Brief Geology in Relation to Work Index Variation To understand the need for a SABC Grinding Circuit it is pertinent to briefly
Slope Stability Determination Methods
Methods suitable for slopes in soil like materials, where the strength of the material can be determined from testing small specimens of the material in a laboratory. Classical soil mechanics slope stability analysis and material strength testing methods are applicable. Methods suitable for slopes in hard jointed rock where the stability of the slopes is controlled by the discontinuities in
Thickener Operation and Flocculant Application
Table of ContentsFloccule DestructionFlocculant DilutionFeed Solids At start-up, the relatively high level of feed solids, 17-20%, called for in design led to difficulties in achieving the degree of flocculation necessary to meet required settling rates. It was recognized that decreasing feed solids would improve thickener performance while reducing flocculant consumption (Figure 2). This was accomplished by recycling thickener overflow to the
Estimating Weak Rock Strength
Table of ContentsShear strength of fracture and weakness planesFrictional properties of plane rock surfacesStrength properties of irregular rock surfacesMethods for predicting shear strength of indented rock surfaces Factors Controlling the Strength of Weak Rock Masses: For the purposes of this paper a weak rock mass is defined as any rock mass in which the effective shear strength parameters are less than:
Kinetics of Sulfuric Acid Leaching of Brass
Effect of Temperature and Acid Concentration: The effect of temperature on the leaching behavior of copper and zinc is shown by the data in Figures 1 through 4. In these experiments, leaching solutions were well stirred at 550 rpm and open to air. “Fraction Extracted” refer to that portion of the total copper and zinc that has been dissolved at time
Carbon in Leach with Oxygen CILO Process for Gold Ores
Table of ContentsLaboratory Test WorkIndustrial Process Application This paper describes a new development in the cyanidation of gold ores, which we expect will result in a major improvement in the way many gold ores are treated. The process has evolved through work at Hazen Research, Inc. for Kamyr, Inc. and in brief, the consists of utilizing oxygen rather than air
Barmac Crusher Efficiency
Because of the nature of the breakage in the Barmac vertical spindle impactor, the 80% reduction ratio is very small, so that when the energy efficiency is calculated by Bond’s method, it appears to be very low. However, the product size distribution contains a high proportion of fines. It is argued that the production of these fines accounts for the
Uranium Recovery by Acid Elution of Resins
Table of ContentsChemistry of acid elutionMinimization of waste disposalMinimization of acid consumptionImproving performance of ion exchange resin An effective technique has been developed to elute ion exchange resins loaded in the carbonate leaching process for uranium recovery. The procedure involved elution with about 0.5 to 2 bed volume of 36.5 g/l. HCl, followed with 5 to 10 bed volume of
Effect of Grinding Media on Flotation Chemistry
The flotation behaviors of pyrite and pyrrhotite in a Hallimond tube were correlated with the galvanic role they developed in two- and three-electrode combinations with mild steel under non-abrasive conditions. These correlations substantiated the hypothesis that a coating of iron hydroxides, originating from galvanic interactions, lowered the flotation responses of sulfide minerals. However, interactions between metal debris particles, generated by
Bioleaching Chalcocite
Table of ContentsLaboratory Bioleaching Bacteria Selection Bacterial Assisted Bioleaching ExperimentsCopper Bioleaching Test Conditions This paper presents results of ongoing research to develop an in-situ leaching process for Michigan copper sulfide ores. The objectives of the work presented here were to determine if the copper sulfide was extractable by a bioleaching approach and to investigate how this process could be incorporated into an
MgO Dolomite Flotation
Table of ContentsReagentsFlotation A selective dolomite flotation process has recently been developed at the University of Florida whereby a two stage conditioning technique is utilized to remove MgO impurities. Previous investigations have mainly involved studies on synthetic apatite/dolomite mixtures in a microflotation (Hallimond) cell. The collectors employed were of laboratory reagent grade and flotation was carried out in a deionized
How to Determine Flocculant Density
The density of a Flocculant is usually evaluated by measuring its buoyant density while settling in a quiescent column. An equation of the general form (Matsumoto and Mori, 1975) is used to calculate the buoyant density (pa), from settling rate (U) and diameter of floc (Df). The constants Kf, α, β and γ depend on shape, porosity and the flow conditions [viscous
Sylvite & Halite Flotation – Salt Mineral Collectors
The flotation of sylvite (KCl) and also some accessory minerals (e.g. kieserite, langbeinite) from crude potash salts are processes used to a large extent all over the world. These separations are made in brines which are in an approximate solubility equilibrium with the mineral phases of the crude potash salts and thus contain concentrations of the crystal ions (K+, Na+,
Repair Ball Mill Discharge Trunnion Crack
Table of ContentsDesign ConsiderationsRepairs Performed There was a continual increase in ball mill lubrication oil consumption. However, visual inspections could not confirm the presence of a trunnion oil seal leak. By the end of month it was assumed that the only possible place for this leak was at the outboard discharge trunnion seal so that oil was leaking into the
Red Dog Mine
The Red Dog zinc/lead deposit in northwest Alaska is the second largest zinc deposit ever discovered. Being developed by Cominco Alaska with startup scheduled for early 1990, it will ultimately be the largest zinc mine in the Western World. Red Dog was discovered by a local bush pilot, Bob Baker, in 1968. The U.S. Geological Survey assessed the find, but
Slags as Ceramic Raw Materials
Slags generated by the ferrous-metals industry can be used to produce high-tech ceramic materials. The properties of these ceramics can be controlled by judicious choices of composition, additives, and processing parameters. Standard methods of materials handling, such as comminution and mixing, are as applicable to slag as to any other mineralogic raw material. Materials and methods The cupola slags investigated