The disadvantages of centrifugal concentrators with periodic unloading of concentrate are the periodic principle of their operation due to the fact that the machine must be stopped to unload the concentrate.

Such centrifugal concentrators are suitable for high-grade precious metal ores with a content of at least 1-2 g / t of gold, silver or platinum, while the concentrate accumulation cycle is usually from 20 minutes to 2 hours.

The CVD-FB used the same Flexicone technology with a flexible cone and floating bed. Concentrator with continuous discharge of middlings, designed for:

- for high-quality gravity beneficiation of fine-grained material (placer sands and crushed ores) containing free gold, silver and platinum, in the industrial extraction of fine and fine fractions of precious metals

- enrichment of ores (tin, copper, zinc, tungsten, titanium-zirconium), in which the content of heavy components is more than 0.5%;

-extraction of fine and ultrafine (-100 microns) heavy fractions in concentrate;

- recovery of polymetals and precious metals from flotation tailings.

Our advantages:

1. CVD-FB combines two concentrators in one: with concentrate accumulation in grooves and continuous unloading of middlings.

2. Simplicity of design and absence of a valve system and outlet nozzles constantly working in contact with an abrasive medium (density up to 45% of the ore).

3. Low cost.

4. There is no requirement for clean water.

The CVD-FB achieves unrivaled gold recovery performance from 3 microns with continuous concentrate discharging from the bowl grooves without power interruption. No water is required for fluidization.

To ensure the required degree of material reduction, the modes are adjusted:

1.by changing the amplitude by changing the position of the rollers

2.revolutions of the cone by changing the frequency of the electric current supplying the electric motor with a frequency converter

3.number of relief holes in the cone

The Flexiсone SD (Self-Discharge) design has a concentrate self-unloading unit of high concentrated material accumulated in grooves , which allows the concentrator to be used in the automated mode of concentrate rinsing without operator intervention. For this, there are discharge holes at the bottom of the bowl. When the cone rotates, the slurry moves only upward and does not enter the concentrate unloading unit. When the rotation of the cone is stopped, the pulp feed is stopped and the rinse mode is turned on. The rinse is supplied with clean or recirculated water through nozzles in the rinse tube attached to the pulp feed pipe. The concentrate is unloaded through the holes in the bottom of the bowl  and discharged through the drain pipe. The Flexicone CVD-FB300SD model has an additional unit for continuous controlled discharge of the intermediate product in the upper groove of the cone. CVD-FB300SD can also be used for the simultaneous beneficiation of polymetallic ores (tin, copper, zinc, tungsten, titanium-zirconium), as well as iron-containing ores where the content of heavy valuable components can reach 0.5% or more.The CVD-FB300SD concentrator combines 2 functions: a centrifugal concentrator for the concentration of precious metals with a concentration factor of 10,000 with metal accumulation and subsequent cleaning (as in all Flexiсone models) and a concentrator with continuous discharge with a concentration factor of up to 500 for enrichment of other minerals. This eliminates the need to use a separate gold concentrator after the centrifugal concentrator with continuous discharge). Thus, similar to the  vibrating tables, the CVD-FB300SD models have 3 products at the output: a gold high concentrate (with a maximum content of gold (PGM) ready for smelting) - up to 10%; middlings, usually sulphide concentrate with a gold content of 100g / ton, and tailings. The concentrator can be used: In industrial technological research of large-volume samples of mineral raw materials; when processing ore and alluvial deposits and ephels of past developments, containing fine and fine gold, as well as tailings of hard rock and alluvial mining; in the industrial processing of technogenic raw materials containing flotation products and  tailings of polymetallic and iron ore mining and processing plants for the extraction of minerals containing iron, tin, tungsten, titanium, chromium, etc .; A distinctive feature of the Flexicone centrifugal apparatus is the use of a flexible cone catcher, which is compressed from several sides by rollers mounted on fixed supports. As a result of compression, the cone in cross-section acquires the shape of a rounded triangle. The concentrator is supplied with a 220 - 380 frequency converter to regulate the speed of the electric motor.

All SD models are supplied with an automatic control system for self-unloading of the gold high concentrate . The main module for automatic control of self-unloading control of the concentrate-head has a programmable timer of the cyclic type. The timer sets 2 parameters:

T1. time of cone rotation and slurry feeding by the sand pump (concentrator and sand pump on / concentrate rinse pump off), in accordance with the recommended reduction rate

T2. rinse time (concentrator and sand pump off / concentrate rinse pump on) 5-10 seconds

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Recommended degree of reduction during the operation of the concentrator (times)

Placer sands 3000-6000

Concentrate for container shooting 400

Prospecting test 20kg -50

Ore concentration - sulfides 100

Concentration of ore rocks - low sulfide 300-500

In the meantime, there is no need to know about it. ”

Concentration time T1 is calculated by the formula (in hours): Weight of concentrate of one withdrawal from the cone (M) divided by the Concentrator capacity (Pr) and multiplied by the degree of reduction (C) T1 = (M / Pr) xC

Auto self-loading mode can be disabled. In this mode, there will be a maximum accumulation of gold concentrate in the grooves until a complete stop and flush, as well as continuous unloading of the industrial product concentrate through the discharge holes in the upper groove.

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TECHNICAL CHARACTERISTICS FlexiСone CVD-FB300SD

Coarseness of the processed material, mm 5

Solid productivity, t / hour 10

Extraction of gold size,% + 50 μm-96-99%, + 10-50 μm 92-96%, + 3-10 μm 50-92%

Pulp density (S / L ratio) from 1/3

The degree of concentration of the volume of continuous unloading middlings 0-500

The degree of concentration of the volume in grooves  0-10000

Bowl rotation frequency, rpm 0-500

Supply network characteristic: 220/380

Shaft power, kW 1.5

Motor efficiency 70%

Power consumption, kW 2.1

Overall dimensions, mm: LxWxH 850x750x600

Weight, kg 90