New Cost-Effective Coating Extends Filter Life and Efficiency

A new low-cost filter-media coating designed to provide easy cake release and reduce blinding for incinerators and similar applications has been developed by Ravensworth Ltd, the embedded-membrane specialists.

The problem: Standard uncoated needlefelts rapidly blind, resulting in increased cleaning and reduced life of the filtration media. Both of these increase costs.

A partial solution: Conventional PTFE treatments, such as the Heimbach Series 90 products, attempt to extend the filter's operational life and reduce blinding by giving the fibres limited nonstick characteristics. The problem with these treatments is that the PTFE only adheres to the fibres, leaving gaping holes in the needlefelt - into which the filtrate particles are drawn. While blinding is reduced compared to uncoated needlefelts, it still occurs, requiring frequent cleaning of the filter.

The better solution: Ravensworth's new Ravlex® CR. Ravlex CR is different (and better) because it forms a quasi-membrane coating structure on the surface of the needlefelt. This dramatically increases filtration at the surface, enhancing cake release and reducing blinding. And because it is a surface coating, it shares some other characteristics with the more expensive filtration membranes, such as increased durability.

This non-laminate PTFE coating gives high air permeability and reduced operational pressure-drop when applied to a variety of needlefelts. Because it reduces frequency of cleaning and replacement of filter media, it minimises mechanical damage and extends operational life.

Ravlex CR is priced competitively and is targeted to the market currently serviced by PTFE treatments such as Heimbach Series 90, BWF CS grades and other low-cost dust-release treatments. However, it offers some of the benefits normally associated with more expensive filtration membranes, both "embedded" and "laminate".

Compared to existing PTFE treatments, new Ravlex CR offers a low-cost improvement to filtration media with added benefits, such as durability and enhanced cake release.

Ravlex CR is suitable for applications with ambient temperatures up to 240°C and can be used on envelopes, shakers, multipockets, pulse jet, reverse air, and industrial vacuum filters. It is available in roll form up to 2.2 metres wide.

For more information on Ravlex CR or the range of embedded-membrane solutions available from Ravensworth Ltd, call Phil Gardner on 01928 571000 or email


energy from waste | incineration


Click a keyword to see more stories on that topic, view related news, or find more related items.


You need to be logged in to make a comment. Don't have an account? Set one up right now in seconds!

© Faversham House Group Ltd 2004. edie news articles may be copied or forwarded for individual use only. No other reproduction or distribution is permitted without prior written consent.