FILTECH moves the industry
The filtration industry is constantly evolving and growing in importance. For 50 years, FILTECH has been accompanying the industry’s development and that of the companies which take on its challenges. One example: Sandler AG
50 years ago, the nonwovens manufacturer Sandler from Schwarzenbach/Saale, Germany, began production of synthetic nonwovens. Only a few years later, in 1970, the company started supplying these materials to the filtration industry, where they were applied for instance as filter media in exhaust hoods in households. The coarse dust filter media constituted the entry into a dynamic market, characterized by testing standards and classification criteria. From the start, the company banked on the utilization of synthetic fibers and single-polymer material compositions. Gradually, Sandler increased the product range.
In the late 1990s, Sandler invested in production lines operating the meltblown technology. This marked the starting point for synthetic HVAC filter media made in Schwarzenbach, Germany, and at the same time, it was the first step towards advancing fine fiber technology.
Step by step, its production capabilities were extended to include multi-layer filter media. The development of the submicron technology enabled the company to incorporate finest fibers of less than 1 µm in diameter. These extremely fine fibers enlarge the synthetic filter media’s inner surface, thus enlarging the effective filtration surface. Featuring submicron fibers, Sandler filter media combine high efficiency maintained in the long-term and low pressure drop. In multi-layer materials this technology enabled the development of depth filter media incorporating pre-filter and fine filter layers for different areas of application.
During this period of growth, visits to FILTECH already provided ample opportunity to network. The early 1990s marked Sandler’s first participation as an exhibitor with a small information booth. The event brought together producers of filter media, machinery suppliers, filter manufacturers, and producers of consumer goods – renowned companies that used the event to exchange views on current topics in the industry and establish new contacts to other industry players. In this way, the trade fair was an ideal platform for information and the presentation of new developments and applications.
Everything from a single source
In the early 2000s, Sandler tapped into applications in automotive filtration. Over the following years, the company expanded its product range of filtration nonwovens to become one of the most extensive in the industry:
In the automobile, pleatable cabin air filter media remove dust as well as pollen and fungal spores. Engine air filters made of nonwovens filter reliably even at high operating temperatures and enable long operating lives owing to their high dust holding capacity. Synthetic fuel filter media separate water and contaminants from the fuel, protecting the engine. In household applications paper is “out” and nonwovens are “in”: Synthetic vacuum cleaner bags stand out through excellent filtration performance, tear-resistance, and resistance to moisture. In heating, ventilation and air-conditioning pocket filter media and pleat filter media let us breathe clean air in industrial buildings, public spaces, homes, as well as hospitals. And even surgical masks benefit from the efficiency of synthetic filter nonwovens in helping to maintain our health.
The filter media, produced without chemical binders or other additives, increasingly established themselves as a textile alternative. Apart from filtration performance, energy efficiency and sustainability have always influenced product development for all areas of application. Sandler emphasizes the recyclability of single-polymer synthetic filter media and the reduction of energy consumption in the filter plant by means of high air-permeability and low pressure drop.
New developments & trends
All along, FILTECH provided an optimum platform for showcasing new developments and learning about trends in the industry. New fields of application, for example filter media for battery separators, also premiere at this event. The trade fair’s group of addressees has been growing steadily, allowing it to become an internationally sought-after event. The relocation of the fair to a new venue in Cologne afforded participants even better conditions for product presentation and booth construction. At this event, exhibitors and visitors from different industry sectors – from aerospace technology through to the timber processing industry – obtain information on the latest developments for clean air. In the course of the past ten years alone, the number of exhibitors rose by more than 60 % and in 2016, the number of visitors was almost double what it had been in 2011. This rate of growth reflects both the quality of the event and the importance of the filtration industry as a whole. For Sandler, FILTECH has been and still is instrumental in expanding the company’s filtration segment.
New norms, new development approaches
The European standard DIN EN 779 for particulate air filters – introduced in 1993 – formed the basis for filter media classification. Each filtration application‘s specific requirements on air quality can be matched to a specific filter class and therefore to the media classified under it. A revision in 2002 made the discharged efficiency of filter media reportable. The medium’s efficiency after the fading of the fibers’ electrostatic charge – either natural or artificially applied during manufacturing – had to be stated in the test report. However, this characteristic did not influence the classification of the filter medium. Nevertheless, for Sandler, maintaining filtration performance throughout the entire operating life of the filter became a main focus in product development. In 2011, Sandler introduced sawascreen premium plus – a synthetic pocket filter medium that maintains high efficiency even after discharge. Thus, the nonwoven media already fulfilled yet another revision of EN779, which took effect in 2012 and made discharged efficiency a criterion for classification. A progressive structure encompassing pre-filter layers and fine filter layers that incorporate extremely fine fibers facilitates mechanical separation effects and makes the synthetic nonwoven an excellent depth filter featuring a high inner surface.
The long-term stability of filtration performance is further influenced by the durability of the filter itself. Innovation for pleatable filter media in HVAC and automotive applications focused on this property in 2013. Sandler developed 100 percent synthetic media processable into accurate and dimensionally stable pleats without the necessity of additional carrier layers or additives. The sawascreen pleat series features a homogeneous, longitudinally oriented structure for optimum pleat geometry and excellent processability on knife as well as rotation pleating lines. These nonwovens offer mechanical stability and moisture resistance. The submicron technology also used in these media creates a high inner surface for high efficiency throughout the entire operating life.
Indoor air quality
During the past years, the filtration industry has continuously gained in importance. The topic of indoor air quality is shaping the market as well as globally applicable testing standards. Apart from the classification of filter performance, the compatibility of practical applicability and low energy consumption is taking center stage. Eurovent certification categorizes filter media according to their energy efficiency and in the wake of the new ISO 16890 standard air filter classification is now more closely aligned with real operating conditions. This categorization references typical patterns of particle size distribution in urban or rural areas, providing a practical description of the filtration properties needed in a specific operational setting.
Sandler’s fully synthetic filter medium enAIRsave reconciles long-term separation efficiency and reduced energy consumption. It features a special multi-layer structure, in which particles are deposited along the entire width of the medium, allowing air to keep flowing through even if the filter is loaded with dust. The pressure drop increases only very slowly and the energy consumption during operation of the filter plant remains low. Owing to a special backing material, the filter medium is self-supporting and the individual filter pockets do not touch in the air stream. Consequently, air can flow through the entire filter surface, making “clean” areas where no dust is collected and thus the reduction of the effective filter surface a thing of the past. This innovation was first introduced to the professional audience at FILTECH 2016.
Conference lectures: Current challenges and future trends under discussion
In the past years, other than showcasing latest developments at the FILTECH booth, Sandler also availed itself of the accompanying conference to address current topics in front of an international professional audience.
In 2011, the optimization of the life cycle costs of synthetic filter media was under review. Dr. Ulrich Hornfeck emphasized, that it is not only purchasing and replacement costs that determine a filter’s total operating costs. Energy consumption during operation of the filter plant is a major influence. Filter media which contribute to reducing energy use through low pressure drop, contribute to reducing total costs.
At FILTECH 2013, Sandler discussed innovations for pleatable filter media. Installation spaces – for example in the automotive industry – are becoming smaller and smaller, increasing demand for this product category and for the durable, accurately processable synthetic Sandler media.
Renowned branch meeting
Notwithstanding numerous specialized congresses around the globe, FILTECH has been bringing together the industry’s “who is who” for 50 years. Today, it is the most renowned trade fair for filtration products worldwide, and has attracted an international audience right from the start.
Networking among the exhibitors enables visitors to survey filter media in downstream stages of production. At FILTECH 2016, for example, Sandler filter media were being processed on a model pleating line at the booth of a filter manufacturer, allowing potential buyers to witness the processability of these media live on site.