Flexicone CVD-FB centrifugal concentrator
Disadvantages of centrifugal batch concentrators are periodic principle of their work due to the fact that for discharging the concentrate the machine must be stopped (or sharply reduce rotation of cone) manually or by using water wash of the annular grooves concentrate.
Such Centrifugal concentrators acceptable only when the poor enrichment or placer ore noble metals containing at least 1-2 g / t gold, silver or platinum, when the cycle of accumulation of the concentrate is from 20 minutes to 2 hours
In our CVD-FB used same processing with floating mineral bed, to keep material suspending . Flexible cone is pressed by three rollers, that are the characteristic feature of CVD-FB and CCFB concentrators (centrifugal concentrator with floating mineral bed) Concentrator with continuous discharge designed for enrichment ores (tin, copper, zinc, tungsten, titanium-zirconium), as well as iron ores, wherein the content of heavy components can be as high as 0.5% or more, extraction of fine particle size (-100 micron) of the heavy fractions in the concentrate, extraction of polymetals from tailings after flotation , old tailings to extract valuable minerals .
The main disadvantages of existing on market continuous discharge concentrators are:
1.Noble metals discharge continuously also, so need to use other batch concentrator next to contuous discharge concentrator to recover noble metals.
2. A low recovery of fine fractions (-100 micron) of heavy minerals due to low residence time of the material enriched in the collecting surface of the bowl, which has a low coefficient of friction between bowl and the pulp that does not create favourable conditions for the rapid separation of the pulp density of the material).
3. Structural complexity and low reliability of the valve system and exhaust nozzles constantly operating in contact with the abrasive medium (density power to 45% of the ground ore), causing them increased wear and, consequently, lower concentrate grade (the increase of its output) and process productivity enrichment of downtime;
3. Excessively high cost , exceed the cost of batch concentrators of similar size 3.5-4 times
4. Clean water requirements
In CVD-FB above problems are solved with achieving unbeatable performance in recovery as low as 3 microns size (gold) with continuous output of concentrate from the grooves of bowl without interrupting the power source. Fluidisation water not required.
In order to ensure a more effective concentration of the pulp with various conditions and particle size distribution of the solid phase, the higher extraction of small and fine fractions of valuable heavy minerals (polymetallic and precious metals) concentrator can be adjusted to achieve the most optimal mode by changing the amplitude and frequency of the bed vibration. The change in the oscillation amplitude is provided by changing the rollers position. Changing the frequency of the torsional oscillations is provided by changing the frequency of the electrical current feeding the electric motors by frequency drive converters