Local filtration provider Filcon Filters is importing abso- lute polypropylene matrix (APM) filter bags, ranging from 0.2 µm to 50 µm, from US-based manufacturer Sun-Central for distribution in South Africa.

Filcon Filters technical sales director Vernon Clarke says there is increasing interest in the APM product from the local filtration industry.

The company is the sub- Saharan African distributor of Sun-Central’s range of filtration products, which includes bag housings, cartridge housings, filter bags and filter cartridges.

Clarke points out that, previously, absolute filtration involved the preservation of cartridge or membrane filters; however, technological innovation has resulted in the development of highly cost-effective absolute filtration using filter bags.

Filcon Filters believes the APM filter bags are more cost effective to use than cartridges. “If an application requires a five-cartridge housing containing five 30 inch 1 µm-pleated polypropylene cartridges to protect five 0.45 µm membranes, the cost would be about R3 250.

“However, this price could be reduced to about R375 using a 1 µm absolute filter bag. While the five-cartridge housings would need to be replaced by a size 2 bag housing for R8 500, the money spent will quickly be recovered,” he explains.

Bags are more cost effective to use as prefilters than cartridges, he states, adding that the range and construction design of the filter bags allow for more filtration solutions, especially in the finer applications.

Further, Clarke says the sealing arrangement of bags in bag housings has undergone major changes over the last few years. This includes changes to the sealing ring, which is chemically resistant and designed to compress when the bag lid closes, thereby providing a positive seal to bypass-free filtration and increasing the efficiency of filtration processes.

He adds that the APM filter bag’s patented Sun Double Seal ring prevents liquid bypass, while the media, which are US Food and Drug Administration compliant, are treated for fibre migration. The thick wall design of the bag resists deformation under pressure.

“We have seen advances with regard to new styles of filter bags, such as multilayered and pleated bags and the welding of bags instead of stitching,” he states.

In addition, bag media have improved in variety and quality. As a result of these innovations, the life of the bag has improved, provided the correct bag is selected, which translates into fewer change-outs.

Clarke points out that, while similar products are available to the market, none have the ability to filter down to 0.2 µm.

Filcon Filters was established in 2000 and has offices in Johannesburg and Cape Town. In addition to representing various international filtra- tion manufacturers, the com- pany has a range of filtration products manufactured to its design in Johannesburg.