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Fly Ash as a Portland Cement Raw Material
Table of ContentsComposition of Raw MaterialsFly Ash Market In 1966, approximately 125 million tons of raw materials, exclusive of fuel, air, water, and power were consumed to produce almost 74 million tons of portland cement in the United States that is about 3,400 pounds of raw material per ton of finished cement produced. To present the figure in another way,
Emulsion Flotation
Table of ContentsBreakingReagentsReagent Recovery Because of the extensive surface area of oil droplets in emulsions, emulsion flotation offers possibilities for the recovery of finely divided mineral particles. Surfactants must stabilize the emulsion and possess an affinity for the desired minerals. Other important factors are the nature of the emulsion ingredients, the relative volumes of the continuous and discontinuous phases, the
Removal of Iron from Aluminum Sulfate Solutions
A study on the sulfuric acid extraction of alumina from some Pennsylvania ferruginous clays indicated that the published electrolytic method seems to be more efficient than the known chemical methods for removing iron from the leach liquor. The main disadvantages of the chemical methods are the consumption of excessive amounts of reagents and/or the precipitation of prohibitive amounts of aluminum.
Dump Leaching
Table of ContentsColumn Leach StudiesNature of Iron Species involved in Dump LeachingStudy of the Chemical Composition of DumpsIron Oxidation and Hydrolysis The dump leaching of low-grade copper ores, as an integral part of the open-pit mining operations in the Southwest, has been practiced for the last fifty years and is increasing in importance as one of the major sources of
Bin Design and Construction
Table of ContentsDesign Criteria for Bin FeedersHopper and Bin DesignBelt FeedersApron FeedersVibratory FeedersFeeder LoadingCorrelation of Solids Flow Theory with Actual Bin OperationBin Operations use of Stainless Steel Conical Hoppers For many years, the Machinery Division of Dravo Corporation has been designing and constructing bins and bunkers as part of overall plant facilities. We have designed bins to handle a variety
Crushing in the Aggregate Industry
In most industrialized countries, the largest element of the mining industry in physical volume is that devoted to the extraction and processing of materials for use as construction aggregates. These materials come from four main sources: (a) Excavation of unconsolidated deposits of sand and gravel (b) Stone quarrying. (c) Processing of slags and other mineral wastes. (d) Manufacturing from clays and
Chemical Aspects of Thickening and Clarification
Table of ContentsInter-relationships of Chemistry, Equipment Design, and CostsCapital Costs versus Operating Costs Chemistry plays a more important role in milling operations than is generally recognized, particularly in fluid-solid separation processes. Chemical aspects are also very important insofar as plant water quality is concerned, and in the manner in which this water quality effects plant design and operation. One aspect
Beneficiation of Iron Concentrates by Cationic Flotation
Silica flotation with amine salts has been a commercial process for years in certain non-sulfide mineral systems. Phosphate rock and feldspar deposits are notable examples. Generally, the quartz is clean and coarse. Primary amines and imidazolines are used, usually in a mole weight range 250-300, and often fairly impure grades of collectors are satisfactory. The synthesis of ether amines involves
Dry Grinding Rod Mills – Dry Rod Milling
Wet grinding rod mills have been used for 50 years to grind ores and to make specification sand. The application of wet grinding rod mills is well understood. Until recently, there have been very few installations of dry grinding rod mills. The basic principles learned from wet grinding rod mills that were used in the application of dry grinding rod
Manganiferous Iron Ore Chlorination
Table of ContentsMaterialsProceduresChlorination of Manganese Oxides The chlorination behaviors of pure iron and manganese oxides were investigated by combining a thermogravimetric analysis (TGA) technique with batch-boat roasting followed by leaching. Ferrous and manganous oxides could be chlorinated readily, but, in the absence of a reductant, the higher oxides of both iron and manganese were difficult to chlorinate. Thermogravimetric analysis curves
Slurry Pumps for the Long Pipelines
Since time immemorial, Mother Nature has been transporting slurries with both air and water serving as the carrier medium. Consider for example the formation of the continental shelves off our coast lines which are being formed by rivers emptying erroded land surface and depositing it into bays and gulfs. As the erosion processes take place, the fines are suspended in
Separation Efficiency
Table of ContentsMineral Concentration Processes and their EvaluationApplications of Separation Efficiency The technical excellence of separation achieved in a mineral concentration process, or any other process where two constituents of any kind are physically separated from each other, is expressed uniquely and quantitatively by the Separation Efficiency: Es = (R – Rg) where R is the percentage of the valuable
How to Select Grinding Mill Liner Alloys for Optimum Wear Resistance
Table of ContentsCriteria for Abrasion ResistanceCriteria for ToughnessAustenitic Manganese SteelsLean Alloy Manganese SteelsAbrasion Resistant Cast IronsField Tests The wear resistance of an alloy in heavy mill liner sections may be quite different from that of the same alloy in small balls and other light sections. This fact was established by means of a well standardized laboratory test that was validated
Removal of SO2 and Production of Sulfur from Smelter Gases
Table of ContentsProcess DescriptionChemistryExperimental ResultsProduction of H2SDiscussion The economic removal of SO2 and production of elemental sulfur from stack gases discharged by base-metal smelters is a challenging-goal. Annually, in the United States, about 3.5 million tons of SO2 are discharged to the atmosphere by smelters. The SO2 concentration of the gases ranges from about 0.5 to more than 3 percent.
Recover Copper from Reverberatory Furnace Slag
Laboratory and pilot plant investigations have indicated that copper recoveries of 50% can be achieved with fine grinding and flotation of a copper reverberatory furnace slag. Microscopic and microprobe studies indicate that the recoverable copper is in the form of matte, chalcocite, and metallic copper; the percentage of copper in particles appearing to be copper-free was from 0.23 – 0.54%. eratory
Slurry Pipeline Cost Estimation
The transportation of mine products incurs a cost which can have a significant bearing on the competitive position of the manufactured product. Clearly, the engineer who is responsible for selecting a mode of transport must base his decision, at least in large measure, on economic comparisons. And today, the engineer usually finds that he has to choose between several modes,
Self-Fluxing Pellet Production
Table of ContentsFundamental test on production methodProblems in practical production of self-fluxing pelletsExperimental use of self-fluxing pellets in blast furnace burdens The development of pelletizing during the last ten years has continued, however, self-fluxing pellets have not been regularly and commercially produced for use in blast furnaces, except as Kobe Steel, Ltd., Japan. This paper tells about unique developments for
Predicting the Block Caving Behavior of Orebodies
Block caving is an efficient mass-production method for the underground mining of large orebodies. However, the block-caving method requires a substantial investment in developmental works, based on the assumption that the rock will cave. Efficient block caving is prevented if the rock forms stable arches or breaks into fragments that are too large to pass easily through the finger raises.
Flotation Plant Optimization
Table of ContentsProcedure & DataDiscussion A mathematical model was developed for the grinding and flotation section of Union Carbide’s Bishop mill and this model was used to indicate how variations in grind, retention time, and calcite and fluorite content effects the mill capacity, tungsten units produced, and the grade and recovery of the scheelite concentrate. A model such as this
Fluorspar Agglomeration
Table of ContentsBriquet PressesDisc ProcessProduction Plant This report will be given in two sections. The first section outlines techniques and equipment to form almond shaped fluorspar briquettes by means of briquet presses, and the second section outlines techniques of the balling disc. Briquet Presses Fluorspar has been briquetted for a number of years and the so called “peach pit” briquet
Leaching of Copper by Fungi
Bacterial and fungal populations were observed in samples taken from the White Pine Copper Company tailing pond and mine, and isolates were prepared of the dominant species. The isolates were then screened for solubilization of copper from tailing, ore, and concentrate during incubation in a carbon and nitrogen supplying medium. Certain Penicillium fungi solubilized significant amounts of copper under neutral
Kelex 100 Reagent for Copper Solvent Extraction
Kelex 100 is a single organic compound designed to selectively extract copper ions from leach liquors having acidities in the pH range of one to three. In the process of extraction, as indicated by the forward direction of the following equilibrium expression, an extremely stable copper complex is formed. The unusual stability of [R2Cu] org in the above equation forces
Rock Fracturing Techniques for In-Place Leaching
The two most stringent parameters for in place fracturing of rock are the lack of any initial void space in the rock which to expand into and the ability to gain access only through drill holes. These two restrictions have proven so severe that as of today the only proven techniques for efficient fracturing are the contained nuclear detonation and
Hydraulic Mining Techniques
The practice of transporting an ore or matrix from a pit area to the plant process area by means of a hydraulic pipeline has long been used by the mining industry. The industries which have classically used hydraulic transportation of ore to the plant include the phosphate mining industry, the heavy minerals mining industry, the clay mining industry, and the