Efficient Filter Systems Based On Fortron PPS Staple Fibers
Shanghai, China - New technical standards, more effective filter systems and innovative filter media are making it possible to reduce emissions from household waste incineration units, combined heat and power stations and cement manufacturing plants. EU and national legislators are also preparing suitable regulations to further cut discharge of heavy metals and dusts. Filters based on Fortron PPS are already performing very efficiently in lowering the amount of undesirable substances in the air. Laboratory testing of a filter hose after ten years' service in a waste-fueled combined heat and power plant also confirms the long service life of these filters.
A routine laboratory test confirmed that the used filter hose based on Fortron PPS fibers still had very good filtration efficiency and was in excellent condition. It displayed no significant mechanical or chemical wear. The cross section also showed predominantly surface-oriented dust deposition, as required. The high tensile force values were within the range of average strength values for new filters. In addition, the clean gas side was virtually free of dust. The yearly average dust emission value measured by the operators was many times lower than the statutory limit and so again confirmed the good result. The hose was one of a total of some 2200 that had been installed in 1996 in a new flue gas purification unit at a waste-fueled combined heat and power plant in Leverkusen/Germany. Here, household waste and similar commercial/industrial waste are incinerated in an environment-friendly process. A needlefelt filter is used for dust separation. It is cleaned at regular intervals by the jet pulse system and operates like a "pneumatic carpet beater". In normal operation, the flue gas reaches the purification unit at a temperature of about 106°C. During start-up, short-term temperature peaks of 160°C may occur. The filter hoses used are produced from Fortron staple fibers and are additionally provided with an easyclean PTFE surface finish because of possible adhesion of dusts to the filter surface.
Fortron PPS – robust material with sustained performance
The requirements for these special filters used in waste incineration units, combined heat and power stations and chemical plants are high – and fibers produced from Fortron PPS are a perfect match. They offer very good resistance to gases, acids and dusts, even at high temperatures, have excellent chemical, hydrolytic and heat resistance (up to 200°C) and are also inherently flame-retardant. In the filtration of flue gases PPS is used in the form of needlefelts and nonwovens. Thus, the Ticona material is already helping to achieve a substantial reduction in emissions.
SOURCE: Ticona and Celanese