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Smelting Unfired Iron Ore Pellets

Fines and concentrates must be consolidated or agglomerated into larger masses before they can be smelted in a commercial blast furnace. Such agglomeration is usually done by sintering, pelletizing, nodulizing, or briquetting. Sintering has been the more common practice, but with the advent of taconite concentrates pelletizing is increasing in importance. Pellets in the blast … Read more

Pressure Leaching of Uranium

Early studies in the carbonate leaching of uranium ores led to the investigation of pressure leaching as a method to enhance the dissolution of the metal values in this system. The initial investigations conducted at the University of British Columbia supplemented by the work done by the group at the A.E.C. Grand Junction pilot plant, … Read more

Improve Hydraulic Backfill Characteristics with Flocculants

Two practical methods for controlling the physical properties of mill tailings for underground stope backfill may be used. The first is classification to remove objectionably fine size fractions, and is commonly employed. The second method, flocculation, has had very limited application. It is the subject of this investigation. This report covers preliminary laboratory studies of … Read more

High Speed Camera in Rock Blasting

The breaking of rock by explosives occurs so rapidly that the details of the phenomenon cannot be observed by the unaided eye. High- (frame-) speed motion pictures offer a means of slowing down the blasting action so that the various phases of the process can be observed and studied. During the last 10 years, both … Read more

Boron Crystallography

In connection with its continuing studies of the characteristics of alloys and alloying elements, we investigated the crystal structure of fused boron. This Boron Crystallography report describes how the structure of fused boron was found to be rhombohedral by the powder method for crystal-structure determinations by X-ray diffraction. The determinations of the crystal structure of … Read more

Volumetric Assay Determination of Uranium

According to Katz and Rabinowitch, workers do not agree as to the solubility of uranium tetrafluoride. However, the conditions under which solubility data were obtained were not always the same. In any event, since both uranium (III) and uranium (IV) fluorides are generally regarded as insoluble in a carbonate-free, nonoxidizing acid solution, in which fluoride … Read more

Solving Flocculation Problems

This is the case history of how two nearby plants in Southwest Virginia solved their water clarification problems. While the solutions should not be considered applicable industry-wide, the methods used in arriving at the answers deserve, consideration. As the plant tonnage increased, it became evident that the amount of coal fines produced in the mining … Read more

Small Mine Operation Shattuck Denn’s Bardon Mine

Small tonnage ore bodies can be developed at a profit on a short life basis. Such is the case of the Bardon Mine in the Big Indian Mining District in San Juan County Utah. Faced with a small initial tonnage of high grade uranium ore, the Shattuck Denn Mining Corporation Engineers developed some new ideas … Read more

Retention Time in Continuous Vibratory Ball Milling

Basic Principles: In a batch mill the length of time during which the material is ground is a direct measure of the energy expended on the material, except possibly for exceedingly fine grinding. The following analysis pertains to a continuous mill operating under these conditions. dE = -C dx/x n…………………………………………..(1) where dE is an infinitesimal … Read more

Pulp Density Measurement and Control

Measuring the specific gravity of a pulp in concentrating plants is a relatively simple procedure, but the desired accuracy is often difficult to attain. Many plants use the system of weighing a known volume of the pulp on a scale. In many cases, this method is quite accurate, but obtaining a true sample presents quite … Read more