CAS Filtration
Producers and suppiers of high quality filter media for water treatment

Filtration Garnet

For use in multi-media filters in conjunction with sand and anthracite.

A limitation of single media filters is that on completion of  backwash the coarser, heavier particles settle first and the finest particles are the last to settle.  Consequently, most of the filtration occurs in the top part of the bed.  This situation can be overcome by using two or three media’s of different density to achieve a bed of increasingly finer media in the direction of flow. The coarser less dense media at the top of the bed provides a large holding capacity permitting the finer media below to provide the quality.

For surface waters with a higher level of suspended solids, anthracite can be placed above the sand forming a triple media filter.

In affected waters, a triple media filter employing anthracite sand and garnet can reduce the number of cryptosporidium spores in the treated water compared to conventional sand filtration.

Filtration Garnet (Almandine ) TDS 2024

Safety Information Almandine Garnet

Multi-media filters are capable of higher filtration rates and increased duty time between backwashes.

CAS Filtration Garnet is produced to comply with BS EN 12910 “Products used for treatment of water intended for human consumption – Garnet”.

Filtration Garnet Properties

Support Garnet

Filtration Garnet must be supported on a layer of at least 100mm of support garnet to ensure that the filtration garnet does not penetrate into the gravel underbed. The design of the underbed is critical if bed inversion on backwashing is to be avoided.

Technical Data Sheet – Support Garnet

Support Garnet Properties

CAS SIS ALMANDINE GARNET v3