Minerals can be classified into several types based on their properties such as hardness, specific gravity, color, luster, streak, cleavage, sizing and crystal form.(Mineral Processing System)
Particles are produced with a continuous size distribution from the coarsest particle in the product to the finest particle (which is theoretically a particle of zero size), when rocks are broken by blasting, crushing or grinding. The continuity of the particle size distribution is broken when the fragmented material is subjected to an imposed process such as sizing or concentration. Any products of the process have their own unique size distribution different from that of the original material.(Mineral Processing System)
Sizing:
Sizing is the general term for separation of particles according to their size.(Mineral Processing System)
The simplest sizing process is screening or passing the particles to be sized through single screen or number of screens.(Mineral Processing System) Screening equipment can include grizzlies, bar screens, wedge wire screens, banana screens, multi deck screens, vibratory screens, fine screens, flip flop screens and wire mesh screens. Screens can be static (typically the case for very coarse material), or they can incorporate mechanisms to shake or vibrate the screen.
Classification refers to sizing operations that exploit the differences in settling velocities exhibited by the particles of different size.(Mineral Processing System) Classification equipment includes ore sorters, gas cyclones, hydrocyclones, rotating trommels, rake classifiers or fluidized classifiers.
Particle size analysis refers to the determination of the particle size distribution of the materials to be processed, which is an important factor in both communication and sizing operations. Many techniques for analyzing particle size are used, and the techniques include both off-line analyses which require that a sample of the material be taken for analysis, and on-line techniques that allow for analysis of the material as it flows through the process.
This process can be achieved by the following machineries:
The electrostatic separators are classified into two main types, such as electrodynamic separators or high tension roll separators and electrostatic plate and screen separators. Both the separators work in similar ways, but the forces applied to the particles are different i. E. Gravity and electrostatic attraction forces. In high tension rollers, the particles that subsequently travel on a drum are charged by a corona discharge. The conducting particles lose their charge to the drum and are removed from the drum with centripetal acceleration. The electrostatic plate separators work by passing a stream of particles past a charged anode. The conductors lose electrons to the plate and are pulled away from the other particles due to the induced attraction to the anode. These separators are used for particles between 75 and 250 micron and for efficient separation to occur, where the particles need to be dry, and have a close size distribution and uniform in shape. Of these considerations, one of the most important is the water content of the particles. This is important as a layer of moisture on the particles renders the non-conductors as conductors as the layer of the water is conductive. Electrostatic plate separators are usually used for streams that have small conductors and coarse non-conductors. The high tension rollers are usually used for streams that have coarse conductors and fine non-conductors. The plate separators used for separating mineral sands ie. Zircon, rutile and ilmenite are separated from the silica gangue. The separation is performed in a number of stages with roughers, cleaners, scavengers and recleaners.
Application:
Beneficiation of ferrous, non -ferrous and rare metal ones.
Recovery of metals from industrial wastes (electronic or electrical
Engineering scrap, cables etc.
Recovery of dielectric materials (e. G. Plastics) for recycling.
Purification of metal and non -metal powders.
Separation of industrial minerals (quarts, feldspar, mica etc.)
Shape and size classification.
This process can be achieved by the following our range of machineries:
Filtration is commonly the mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size and filter thickness). Filtration is also used to describe some biological processes, especially in water treatment and sewage treatment in which undesirable constituents are removed by adsorption into a biological film grown on or in the filter medium.There are many different methods of filtration; all aim to attain the separation of substances. Separation is achieved by some form of interaction between the substance or objects to be removed and the filter. The substance that is to pass through the filter must be a fluid, i.e. a liquid or gas. Methods of filtration vary depending on the location of the targeted material, i.e. whether it is dissolved in the fluid phase or suspended as a solid. Two main types of filter media are employed - surface filter, a solid sieve which traps the solid particles, with or without the aid of filter paper (e.g. Belt filter, Rotary vacuum-drum filter, Cross flow filters, Screen filter), and a depth filter, a bed of granular material which retains the solid particles as it passes (e.g. sand filter). The first type allows the solid particles, i.e. the residue, to be collected intact; the second type does not permit this. However, the second type is less prone to clogging due to the greater surface area where the particles can be trapped. Also, when the solid particles are very fine, it is often cheaper and easier to discard the contaminated granules than to clean the solid sieve.Filter media can be cleaned by rinsing with solvents or detergents. Alternatively, in engineering applications, such as swimming pool water treatment plants, they may be cleaned by backwashing. Self-cleaning screen filters utilize point-of-suction backwashing to clean the screen without interrupting system flow.
Filtration Equipments:
Vacuum Filtration Unit:
Filter Presses
Vertical Pressure
Beltpress Filters
Granular Media Filters
Pressure Filtration Unit:
Filter Presses
Vertical Pressure
Beltpress Filters
Granular Media Filters
Dewatering:
De-watering is an important process in mineral processing. The purpose of dewatering is to remove water contained in particles. This is done for a number of reasons, specifically, to enable ore handling and concentrates to be transported easily, allow further processing to occur and to dispose of the gangue.