The mining and mineral industries generate large amounts of fine particle slurries which are presently dewatered by impoundment, thickening, filtration or flocculation. Flocculation is a primary unit process that plays a major role in solid-liquid separation throughout the processing industry and waste water treatment facilities. The flocculation is carried out by agglomerating fine particles into … Read more
The moisture content of coal has become more important in the product analysis. The high content surface area and corresponding high moisture of fine coal can contribute to most of the overall product moisture. As the preparation engineer exhausts his talents and capital budget to bring product moisture into compliance, alternate methods of fine coal … Read more
Flocculation is the process of agglomerating fine particles in solid-liquid suspension by using a high molecular weight long chain polymer as a flocculant. It is used industrially as a pretreatment step to solid-liquid separation and also as a separation method for recovering valuable minerals from gangue using selective flocculation. Spontaneous floc formation takes place due … Read more
Shear-flocculation is a term used by Warren (1975) to describe a phenomenon observed when scheelite (CaWO4) was stirred in the presence of a surfactant. At high stirring speeds in the presence of 10 -4 M sodium oleate, the particle size of the scheelite slurry increased. However, in the absence of a collector and/or at low … Read more
In order to maximise the benefits obtained from flocculating agents when used as settling aids in high rate and conventional thickeners, it is often necessary to dilute the thickener feed prior to flocculant addition. In some cases, no flocculation at all is possible unless dilution water is used. The most common method of diluting thickener … Read more
Paste is a high density mixture of water and fine solid particles with a relatively low water content (10-25%) such that the mixture has a consistency as measured by the ASTM slump cone test from slightly greater than zero up to nearly 12 inches (305mm). Particles of different size classes will not segregate or settle … Read more
Fundamental problems exist with the drying of fine coal. The moisture content of fine coal after mechanical dewatering is often too high to allow the coal to be added directly to the coarser (plus ¼ in) fractions and it must be further dewatered. Also, fine coal is lost and expelled with sludge in most current coal … Read more
Phosphatic clay waste is one of the principal waste products resulting from the mining and benefication of Florida phosphate ore. This waste material, which is comprised of ultrafine particles (70 pct less than 1 µm), responds poorly to conventional solid-liquid separation techniques and is currently disposed of by impoundment behind earthen dams. The overall natural … Read more
The Florida phosphate industry currently produces more than 80% of the total U.S. supply of phosphate rock. The production of this critical mineral is accompanied by the generation of large quantities of dilute phosphatic clays. The disposal of these phosphatic clays has been a problem to the Florida phosphate Industry since the introduction of large-scale … Read more
Chemicals: Reagent grade H2SO4 and KOH were used for pH adjustment. Aluminum sulfate was used for coagulation and zeta potential studies. Percol 368 a solid grade highly cation flocculant by Allied Colloids Inc. was used for flocculation and zeta potential measurements. Methods: Zeta potential measurements of the slurry as received and/or after treatment with different … Read more