BHS Widest Continuous Indexing Vacuum Belt Filter

Product Announcement from BHS-Filtration Inc.

BHS Widest Continuous Indexing Vacuum Belt Filter-Image

BHS Announces the World's Widest and Largest Continuous - Indexing Vacuum Belt Filter Ever Built

With an active width of 3.50 meters (11.5 feet), BHS is pleased to announce that we have manufactured the widest and also largest belt filter ever built. The machine has overall dimensions of 5.3 meters (17 feet) wide x 24 meters (79 feet) long with a weight of 28 tons. The customer has ordered two types of this machine from BHS in order to filter and to wash high-value solid particles out of an alkaline solution

The BHS Continuous - Indexing Vacuum Belt Filter technology provides for thin-cake, as small as 5 mm, production on a continuous basis.

Vacuum filtration, cake washing, vacuum or hot-gas drying with mechanical compression and automatic and continuous dry cake discharge steps are tailored to meet specific process requirements.

Preliminary bench-top tests can be conducted in the BHS Process & Filtration Laboratory while rental filters are available for onsite testing starting from 0.1 m2 to 0.825 m2.

Read the Technical Report - "Evaluation of a Continuous-Indexing Vacuum Belt Filter As a Replacement for Filter Presses For the Manufactureof a High-Value Specialty Chemical Product"

BHS Vacumm Belt Filters

Ideal for:

  • fragile materials
  • compressible cakes
  • high volume production
  • washing problems


  • very low maintenance
  • gastight, cGMP options
  • plate cake squeezing option
  • Confiltro cake drying with:
  • forced convection
  • conduction
  • vacuum

General Description


The BHS-vacuum belt filter can be used for separating sedimenting and abrasive solids from suspensions with little wear. The various filtrates are separated exactly and without intermixing. If required, the filter cake can undergo further treatment in the form of multiple reverseflow washing, suction drying or pressing.

Technical Description

BHS-vacuum belt filters are continuously operating, pneumatically driven horizontal vacuum filters. A circulating belt, moving in cycles, is the filter medium. The suspension is fed continuously or in batches onto the belt, the filtrate is sucked away from below. The filter cake forms on top of the belt and under-goes further treatment in the form of washing, extraction, suction drying or pressing. With very little vacuum loss, the belt is stationary during filtration process. When the belt moves forward, the vacuum trays are vented so as to ease strain on the belt.

Vacuum trays

The vacuum trays are divided into zones corresponding the length of belt feed. Supporting grids with large open sections are provided in the vacuum trays to support the belt.

Filtrate drain

Each individual zone in the vacuum trays is separately connected to the filtrate manifold. The filtrate manifold is divided up in line with the zones for filtrate separation. Rapidly opening and closing shut-off valves cut out the vacuum when the belt advances and vent the filtrate chamber.

Belt conveyance

The continuous, circulating filter cloth belt is moved in cycles by pneumatic cylinder and conveyer roller. While the belt is stationary, vacuum is applied to the trays, holding the belt in place. The length of cloth moved forward corresponds exactly to one zone length and is taken from the belt storage device. The return movement is completely free from strain.

Suspension delivery

The suspension is delivered from a stationary distributing facility. An oscillating delivery unit can be provided for heavily sedimenting sus-pensions.

Cake washing

Washing media are delivered by spray systems or distributing channels. The delivery units can be positioned with precision on the vacuum trays.

Cake discharge

Part of the cake is removed during forward feed, the remainder when the extraction roller travels back. A mechanical scraper removes any cake re-sidue still adhering to the cloth.

Cake pressing

A pressing plate is pneumatically or hydraulically pressed onto the cake for one cycle unit. Compressed air or hot air is additionally blown through the cake.


Following the normal filtration, washing and dewatering stages, it is possible to apply a variety of drying systems to dry the product.


The Confildry version consists of heatable upper rams and heatable vacu-um trays. Hot gas can also be drawn through the cake. This produces a high level of heat transfer, resulting in efficient drying.


The BHS vacuum belt filter can be used to good effect where the following criteria need to be met:

  • Several consecutive process steps
  • Enclosed gastight production
  • Fully automatic operation
  • Temperature up to 95°C
  • Dewatering by mechanical expression up to 6 bar
  • Filter cake drying

Encased Filters

To meet customer specifications, various types of encased filters are available:

  • simply hood type
  • with closed hood over the entire filter
  • closed box type
  • gas- and pressure tight box type
  • pharmaceutical type

Normally, an encased box type will be used here, with particular attention focused on surface quality (Ra up to 0.8µ), processing directives (GMP) and the use of permissible materials (FDA).



  • Drug filtration
  • Penicillins
  • Fermentation solutions
  • Semi-synthetic antibiotics


  • Flavouring extraction
  • Citric acid
  • Ascorbic acid
  • Pectins
  • Cakoa butter

Environmental technology

  • Gypsum from flue gas desulphuration plants
  • flue ash from waste incineration plants


  • Initial and intermediate products
  • AZO dyestuffs
  • Pigments
  • Phthalocyanines


  • Detergent additives
  • Organic and inorganic additives
  • Precipitation residue
  • Active carbon
  • Heavy metal salts


  • Alumina
  • Ion exchanger
  • FCC


  • Filter cloths: PP, PE, PVDF, Luxilar, PA
  • Components contacting the product: special steels, PP, PVDF
  • Seals in all common sealing materials

Technical data may change due to technical progress. Subject to modification without notice.

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