Pilot Scale Testing Coal Air-Lift Hydrohoist

Primary underground coal transportation systems, such as conveyor belts, rail haulage, and mechanical hoists, have numerous inherent safety hazards. During the period 1990 to 1992, 12% of all the reported 31,266 accidents that occurred at underground coal mines were associated with powered haulage, and 52% of all haulage accidents, including surface areas of underground mines, […]

Cyanide Safety

Cyanide Training Proper care and handling of Sodium Cyanide Why the need for training? To help ensure that Team Members are not exposed to harmful concentrations of cyanide through proper handling procedures. To assist all Team Members in understanding how cyanide is used safely and the environment is protected. To ensure all Team Members are […]

Flow Behavior Change Determination in Mineral Suspensions

Mineral suspensions show Newtonian flow properties at lower solid concentration, but change into non-Newtonian regime as the solids content is increased. For Newtonian fluids viscosity is independent of shear rate, but for non-Newtonian fluids it varies with rate of shear. Therefore, measurement of viscosity at a shear rate, different from the process will be futile […]

Assay Laboratory Standards & Quality

It is important to have Assay Laboratory standards over a range of grades. This alone may preclude the material being sampled from serving exclusively for the preparation of standard material. One of the standards must have as close to an absolute zero value as possible. At least three and if possible five other standards should […]

Nitrous Sulfuric Acid Pressure Leaching of Platinum Group Metals Sulfide PGM

Simplistically, nitrogen species oxidize the sulfide and solubilize some of the metal values. In essence, the silver, copper and less noble metals are dissolved in the leach. The slurry is screened, thickened and filtered. Two different solids are produced. First, sulfur pellets are recovered. Then, the insoluble fine leach residue, consisting primarily of lead sulfate, […]

Flotation Bubble Contact Angle Measurement Method

Among the wide variety of modern surface chemistry analytical techniques, contact angle measurements still remain attractive for wetting characterization of solid surfaces. It is demonstrated that the contact angle value depends on the technique used when nonideal, heterogeneous and rough, solid surfaces are examined. Reagents and Materials Three different solid surfaces were used in the […]

Cementation of Gold on Copper & Zinc Electrochemistry

The cementation of gold on to copper and zinc in ammoniacal solutions has been investigated using electrochemical techniques and conventional cementation experiments: Studies of cathodic reduction of Au(NH3)2+ have shown that the cathodic reaction can be expressed as: Au(NH3)2+ + e = Au + 2NH3 and the standard reduction potential, E°, has been estimated to […]

Nonconventional Fluid Bed Drying

Drying System Design The fluid bed dryer has been designed for the specific requirements of drying a 6 mm x 0 (¼” x 0) feedstock of anthracite culm and occasional intermittent feeds of anthracite silt. The feed moisutre of the culm ranges between 16 and 18 per cent by weight and is approximately 24 per […]

Efficient Crushing in Comminution

Recent research into the mechanisms of crushing processes has led to the establishment of new criteria for the effective design and operation of comminution plants. This paper reviews this work and gives examples of the productivity gains and cost benefits that have been achieved in the practical application of these findings. Large cost reductions have […]

Carbon In Pulp Screening using High Frequency Screens

Mechanical Development – Laboratory Testwork Derrick Manufacturing Corporation originally developed the 1.22m x 2.44m Flo-line screen for rock chip removal from drilling muds. It features a 3° reverse angle deck slope and is powered by dual 1.1 kW TENV motors rotating in opposite directions. Figure 1. Screen feed enters from the lower end and, due […]