Prism Si4 calibrated glass media

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Engineered from high quality recycled plate glass (not bottles), Prism Si4 is Engineered to Outperform and is supplied with 2 ‘Grain Curve’ options, medium grade and fine grade. Now, you can select a filtration media that combines the best features of different media types – high dirt loading, low operational pressure differential, anti-fouling properties, anti-compaction properties & more – Prism Si4.

The durability of Prism Si4™ is outstanding. Its integrity is assured for at least 30 years.Prism Si4™ offers high filtration performance, >1um particles may be eliminated in optimum conditions.





Properties such as the microscopically smooth surface and aseptic characteristics of Prism Si4™ Technology prevent bacteria from proliferating within filters, which eliminates the need of dosing chemical biocides. Prism Si4™ Technology includes, among other unique qualities, a special grading curve calibration technology.

This is known as ‘Anti-Compaction’ technology.How does Prism Si4 avoid compacting and segregation? To do that, after material classification, and grinding process, the grains are separated by sizes via a light separation procedure.

Every different kind of glass and colour projects a different wave within the light spectrum. The grain processing machines recognise the type of glass via light refraction, and a compressed air flow separates and grades glass pieces as they fall in a vacuum chamber.

After this process, exact quantities of every grain size are mixed to create a curve able to avoid compacting. There is an exact percentage of every separate grain size inside each bag of Prism Si4. For example in the STAGE 3 ultrafine grade there is 21% of 0,1mm grain size. No more or less!

This is a key benefit of Prism Si4™, as not only does it provide equalized particle entrapment throughout the filter bed by preventing ‘clumping’ and ‘channelling’, it also contributes to a very low operational pressure loss during filtration minimising energy consumption.


  • Medium Grade

  • Grain sizes: 0.6mm – 1.2 mm
  • Recommended backwash velocity: 40-4
  • 5m3/m2/h
  • Bed depth: approx 900mm
  • Air-scour: 70-90m/hr
  • Bulk density: 1350kg/1m3
  • Fine Grade (Optimum turbidity reduction)

  • Grain sizes: 0.4mm – 1 mm
  • Recommended backwash velocity: 40-45m3/m2/h
  • Bed depth: approx 900mm
  • Air-scour: 70-90m/hr
  • Bulk density: 1450kg/1m3
  • Filtration rates from 6m3/m2/hr to 40m3/m2/hr depending on application.
  • Available in 20KG sacks or 1 tonne Supersacks.
  • An ENVIROFORM Product.
  • Fully Recycled Glass Material



Get increased performance now.

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Prism Si4 calibrated glass media


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