Filter Selection
Filter selection is based on product type (material to be conveyed), particle size and application.
‘Selecting the correct filter is vital for efficiency and compatibility’
Whether for multi-product use, hazardous duty (Flameproof or ATEX) or where steam sterilization is required it is essential to use the most appropriate filter for the process.
Bag Filters
Standard bag-filters are white PTFE coated polyester fabric (Goretex type material) and fully FDA compliant. Bag filters are the most commonly used filter type and offer low operating costs but do have some limitations when compared to cartridge filters.
Bag filters do have one main advantage over cartridge filters as they can be easily cleaned using a filter-shaker mechanism in place of reverse air-jet. This is ideal for sticky products that tend to adhere to the surface of the filter membrane.
Cleaning and storage instructions;
Filter bags are washable but this does affect life-span. It is also difficult to validate washing of filters and filter bags should ideally be product dedicated. A more successful solution to washing the filters is to use a vacuum cleaner to remove surface contamination. To maintain integrity the bag filters should be stored in sealed bags when not in use.
Cartridge Filters
Cartridge filters have a pleated polyester construction also with PTFE FDA compliant coating. The pleated design increases the surface area of the filter and is therefore more suited to high-flow applications.
Cleaning and storage instructions;
Filter bags are washable but this does affect life-span. It is also difficult to validate washing of filters and filter bags should ideally be product dedicated. A more successful solution to washing the filters is to use a vacuum cleaner to remove surface contamination.
To maintain integrity the bag filters should be stored in sealed bags when not in use.
Stainless Steel Filters
Stainless steel filters are normally of a pleated design similar to cartridge filters. Although the initial cost of stainless steel is much higher than alternative media, their life-cycle is infinite. This is because the filters are extremely durable and can be steam sterilized allowing total removal of any debris lodged in the filter surface. Effectively the filter is in ‘as-new’ condition once cleaned properly. The fully sterilizable feature makes stainless steel filters ideal for highly toxic products.
Stainless steel filters are anti-static as standard due to the all metal construction but are limited regarding particle retention when compared to similar size fabric or cartridge filters.
Cleaning and storage instructions;
Stainless steel filters are also suitable for steam sterilization or Autoclaving.
All s/s filters should be stored in a protective cabinet to reduce any surface damage risk and should only be stored in bags if completely dry.
High temperature cleaning will also aid the drying process.
Get in Touch
If you would like to speak to one of our experts regarding our range of filters or you would like a quote for one of our products, send us a message using our Contact Form or call us on +44 (0)1702 549 777.
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