Vacuum Disc Filter

Vacuum Disc Filters from VDF represent the most advanced technology for continuous pressure filtration.

Wherever difficult to filter products or large amounts of suspension are to be filtered – such as concentrates from ore, coal and mineral processing or their tailings – VDF Disc filters offer outstanding solutions.

The basic principle is also known as hyperbaric filtration and very simple: a continuous rotary filter is installed completely in a pressure vessel filled with compressed air of up to 7 bar (a). A pump feeds the slurry into the filter trough in the pressure vessel. The filtrate flows through the filtrate pipes to the control head of the filter and from there to the filtrate separator. The filter cake is removed from the filter cloth by a reverse blast of compressed air and discharged through a solids sluice from the pressure vessel.

filtration with high differential pressures Δp up to 6 bar (g)

most modern disc filters with innovations known and proven by VDF Disc filter technology

option of installing steam hoods for steam pressure filtration

closed process area (hermetic) inside the pressure vessel

manholes allow quick and easy access to the pressure vessel from both sides and allow easy replacement of spare parts via a drawbridge

reliable double gate valve for solids discharge

low maintenance requirement due to innovative wear protection components

The basic principle is also known as hyperbaric filtration and very simple: a continuous rotary filter is installed completely in a pressure vessel filled with compressed air of up to 7 bar (a). A pump feeds the slurry into the filter trough in the pressure vessel. The filtrate flows through the filtrate pipes to the control head of the filter and from there to the filtrate separator. The filter cake is removed from the filter cloth by a reverse blast of compressed air and discharged through a solids sluice from the pressure vessel.

filtration with high differential pressures Δp up to 6 bar (g)

most modern disc filters with innovations known and proven by VDF Disc filter technology

option of installing steam hoods for steam pressure filtration

closed process area (hermetic) inside the pressure vessel

manholes allow quick and easy access to the pressure vessel from both sides and allow easy replacement of spare parts via a drawbridge

reliable double gate valve for solids discharge

low maintenance requirement due to innovative wear protection components.

VDF disc filters are available in various sizes with filter areas up to 168 m2 per filter unit.

Applications of the VDF Disc filter:

Alumina (Bauxite Residue)
Coal
Iron Ore
Base Metals
Tailings

Features and benefits:

filtration of fine-grained products
filtration of large quantities of suspension
minimal footprint
less need for filter cloths as filter area is much smaller compared to discontinuous filter equipment
fully automatic and continuous operation
lowest residual moisture, especially with steam pressure filtration
saving of costs for thermal drying up to the avoidance of thermal drying
possibility for re-usage of residues
significant improvements in product handling and transport

A vacuum disc filter can provide highly precise filtration in the smallest pads. Several discs in-line are connected to a center which turns through slurry and the evacuation zone. Each circle is comprised of sectors, molded like a cut of pizza. Each sector is either furrowed or made of punch plate to permit fluid to pass through a cloth sack, into the division, and out the center barrel. Each disc filters the slurry at the same time on both sides. Vacuum disc filters are ideal for these cases in which the slurry has highly liquid substances and the cake is easily dischargeable.

Vacuum Disk Filters are kind of continously running filters ant their most important advantage is can be manufactured for very high capacity and occupy place less than Vacuum Drum Filters. Design and production of Vacuum Disk Filters are made of result of R&D Works about Pilot Filters on our laboratories with high technology in way of provide high efficiency, high capacity and low humidity.

A vacuum disc filter consists of five main parts :-

Valve: One side of the valve confronts the two gaps of the vacuum pump which one is for vacuum and the other one is for blow evacuation. The other side of the valve confronts bridge blocks of filter with isolated cake formation, cake drying and blow evacuation sections.

Sectors and Sector Bags: Metal, plastic, fiberglass or wood materials can be used to produce these sectors. The cake is captured by a sector bag as the liquid passes through the center barrel, out to filter valve and into the sector.

Center Barrel: A center barrel consists of a connected series of tubes; one for every sector, with a hole for each disc.

Filter Tank and Agitator: The filter tank containing the slurry is anticipated for filtration. To keep the liquids to solid ratio steady, an agitator spins and continuously mixes the slurry.

Variable Speed Drive: The variable speed drive is powered by an electric engine, permits the revolution speed to differ, correlates for efficiency of the particular application.

Sabari Sashidharan

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