Longwall Pillar Design Method
The past decade has provided a wealth of practical experience with longwall pillar design. Design formulas developed specifically for longwalls have proven their value in numerous applications. Analytic methods, including numerical models, have also made important contributions. These advances have been based on basic research into abutment loads, coal pillar mechanics, and the interaction between […]
Grinding Ball Wear & Breakage by Impact & Abrasion Tests
Impact and abrasion properties of various commercial US grinding balls were evaluated and compared by the Bureau of Mines, US Department of the Interior. Laboratory tests were conducted on balls obtained from eight major US manufacturers. The balls included forged steel, cast steel, and alloyed white cast iron and were subjected to repeated impacts until […]
Leaching Supergene Copper Ore – Atacamite & Chrysocolla
The US Bureau of Mines is conducting core leaching experiments with sulfuric acid on oxide copper ores from the Cyprus Casa Grande and Asarco-Freeport Santa Cruz deposit in Arizona to further the understanding of the leaching process in supergene copper ores as it relates to in situ mining. Leach solutions from atacamite mineralization contained 5 […]
Conveyor Belt Capacity Modelling
Since changing the capacity of operating systems can be very expensive, it is important that mining engineers have accurate capacity design tools. Although many modeling approaches have been proposed in the literature, simulation models are widely regarded as providing the most detailed and flexible design approach. Over the last three decades, a number of discrete-event […]
Column Leach Test Procedure & Variables
A hydrometallurgical testing program to define the basic criteria, like recovery and sulfuric acid consumption, for a commercial heap leach system design, to process the oxide Copper (Chrysocola). Leach parameters such as, amount of sulfuric acid in the cure solution, cure technique, particle size of the material, leach solution’s flowrate application, leach solution’s acid strength […]
Heap Leach – Ore Permeability Testing Method
The test method developed to determine the permeability of ore under increased confining pressure was modified from the Bureau of Reclamation test standard, Designation E-14 (Bureau of Reclamation, 1974). The test apparatus consists of a 12 inch diameter steel cylinder, bottom porous stone, base plate with a drain, porous top plate, reaction frame, and a […]
Water Hyacinth Roots & Water Purification
In the environmental treatment field, if the water hyacinth root is to be considered as a viable treatment method for metal-bearing waste streams, sorption data and the corresponding isotherm parameters must be generated and made available to the scientific and engineering communities. The maximum sorption uptake value is an important feature of the sorbent characterizing […]
Making Zirconia by Zirconium Chlorination
Preparation of ZrO2 from ZrCl4: The products of chlorinated zircon which consist mainly of zirconium tetrachloride and silicon tetrachloride are collected under the afore-mentioned conditions. This collected ZrCl4 is calcined at 900°C for 1 hour to produce commercial grade of ZrO2. Fig. (5) shows that a maximum recovery of ZrO2 of – 92% is obtained from […]
Hydrophobic Particle Aggregation & Flotation
In view of the poor floatabilities of fine particles their treatment prior to flotation becomes essential and aggregation is a means for improving the recoveries. Many of the variables which govern the flotation process also influence the aggregation mechanism and may be classified into physical, chemical and geometrical. Earlier investigations report the effects of particle […]
Evaluate Spiral Concentrator Circuit Performance
Circuit analysis can be used to evaluate the overall effectiveness of various configurations of unit operations in mineral and coal processing circuits. This powerful tool, has regretfully seen only limited application in the analysis of coal processing circuits. Strictly speaking, this method can only be applied if particle-particle interactions do not influence the probability that […]