A disc filter consists of several discs. Each disc is made up of several pie-shaped sections.  Disc filters can operate as either vacuum disc filters or pressurized disc filters. Because a pressure differential is applied across both disc faces, the effective filter area of a disc filter is much greater than that of a drum filter requiring the same floor space.

Vacuum Disc Filters

The basic steps in the operation of a vacuum disc filter are:

  1. Cake Formation - An internal valve opens.  This allows vacuum to be applied to the underside of the filter screen.  The cake starts to form on the part of the drum that is submerged.
  2. Cake Drying - As the drum rotates out of the slurry, the drying portion of the cycle begins. Vacuum continues to be applied in order to create the pressure differential necessary to remove the filtrate.
  3. Cake Discharge - An internal valve is used to close off the vacuum at this point.  The discharge mechanism can be either a scraper, belt, roll or string. Compressed air can be used to help remove the cake from the filter screen.

Pressurized Disc Filters

  • A pressurized disc filter applies relatively low pressure gas to the slurry side of the filter screen.
  • The compressed gas (either air or recirculated process gases) is used to create the pressure differential necessary to achieve filtration.
  • The filter is contained in an air-tight housing.
  • Filtration begins when the disc leaves the slurry.
  • Internal valves and piping channel the filtrate away from each disc and into a receiver.
  • From the receiver, a compressor is used to recirculate the process gasses back into the filter hood.  The filtrate is pumped away for further use in the process.
  • The filter housing is designed to contain the recirculated process gasses.  It can be manufactured from various materials of construction.

Precoat Disc Filters

A Precoat Disc Filter can function as either a vacuum disc filter or a pressurized disc filter. 

Capillary Action (Ceramic) Disc Filters

Ceramic filters are used to dewater mineral concentrates and pelletising feed slurries. Micro porous ceramic discs replace conventional filter cloth. Capillary action draws liquid through the pores, and only a small vacuum pump is required, resulting in significantly reduced energy consumption.

The range of capillary action filters available covers a variety of process sizes and throughput requirements. Filtering capacity can reach as high as 100 tons an hour per unit.

With more size options and lower power consumption than with conventional vacuum filters, this product can offer greater productivity for your filter system.

Pressurized Disc Filters

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