ALKEGEN Hall 7 / L24

Alkegen has developed a next‑generation fiberglass filtration material engineered to deliver high water‑repellency performance without the use of added per‑ and polyfluoroalkyl substances (PFAS).

The innovation supports our broader objective of offering safer, more environmentally responsible materials while maintaining the high durability, efficiency, and mechanical robustness expected of advanced filtration products.

The new material incorporates a proprietary chemical composition applied in flat‑sheet form, eliminating the need for additional PFAS‑based treatments.

A comprehensive evaluation program was undertaken by Alkegen’s Research and Development Team to validate its functional performance.

Testing confirmed that the material retains full water‑repellency properties, demonstrates stable interactions with commonly used sealants and adhesives, and meets established filtration performance expectations, including quality factor, particle‑capture efficiency, pressure drop, and mechanical integrity.

Performance was assessed at both the flat‑sheet level and within fully assembled filters—specifically panel and V‑bank configurations—tested according to EN1822/ISO 29463 and ISO 16890 standards.

Filters utilizing conventional PFAS‑containing fiberglass material served as benchmark comparators, enabling direct validation that flat‑sheet performance is reliably translated to final filter assemblies.

This no‑PFAS‑added fiberglass media is now commercially available and designed to support manufacturers seeking high‑performance filtration materials with improved environmental and human‑health profiles.

Purefrax® Hot Gas Filters (HGFs), also known as Ceramic Candles, are used for high temperature dust filtration and emission control. Where traditional filter bags can only be used up to temperatures of approximately 260°C, HGFs are typically used for dust filtration in the 300-550°C range with the possibility of use up to 900°C. Commonly, HGFs are selected to replace Electrostatic Precipitators and Cyclones, particularly for their greater filtration efficiency and capacity of high temperature operation.

Key Drivers for High-Performance Hot Gas Filter Adoption:

• High‑temperature operation for heat‑recovery.
• Expanding high temperature applications (e.g. Gasification).
• Use of catalyst for removal of harmful gases.

However, there are certain applications where the brittle ceramic material properties of standard HGFs can be problematic. Particularly in earthquake-prone regions but also heavy industrial applications where there are additional stresses or movement.

For example, the use of HGFs in facilities such as glass manufacturing is a well-accepted technology, but when we include the risk of earthquakes and the consequential furnace shutdown, there can be reluctance to use this technology. In cases like these, filter bags are adopted as a compromise. They are made of flexible fabric substrate and resilient to tensile and shear stress, however they can only be used in lower temperatures.

Enabling safe and reliable use of HGFs in environments where ceramic filters have traditionally been a barrier has been one of Alkegen’s primary research and development projects. Today, we are able to share our innovations in this area, announcing the introduction of our new reinforced HGFs, designed to enhance resilience, reliability and performance of HGFs in extreme environments.

The Innovation

The majority of HGF breakages in applications occur at the flange section. This is where the HGF element is subject to the most force, as the flange supports the weight of the whole filter (approximately 10kg for a 3m piece). Alkegen’s new...

At Alkegen, we have studied the effect of ageing on the efficiency of fine fiber Meltblown in dynamic conditions. One HVAC grade MB7073 with an efficiency ePM1 75% according to ISO 16890 has been selected for this study. The meltblown media was produced in‑house by Alkegen using proprietary fine‑fiber technology.

This grade has filtered ambient air (rural environment) at media velocity 10.5 cm/s during the seven-month study.Temperature and relative humidity were recorded throughout the study.

Filtration properties – efficiency with KCl aerosol and pressure drop – were measured regularly during the ageing study, which was conducted at Alkegen’s filtration laboratories under controlled conditions. Over the seven-month study, efficiency remains steady and pressure drop increases slightly.

This stability can be explained by production on state-of-the-art equipment, and optimization of the additives used. These results demonstrate that the material maintains stable efficiency and acceptable pressure drop over seven months of real‑environment exposure, confirming its suitability for long‑term HVAC filtration applications...

Hydraulic filter performance evaluation has traditionally relied on steady-state multi-pass flow testing as defined in ISO 16889:2022, which enables reproducible assessment of particulate removal efficiency and contaminant capacity under controlled static flow conditions. However, many hydraulic systems operate under dynamic duty cycles characterized by fluctuating flow rates and transient loading conditions, which can significantly influence pressure drop development, particle capture mechanisms, and dust holding capacity (DHC). The ISO 23369:2022 standard introduces a cyclic flow multi-pass test methodology to better reflect these operational realities.

At Alkegen, our research and development team has completed a systematic blind comparison study of static and cyclic flow testing on finished hydraulic filter cartridges sourced from both the open market as well as manufactured by Alkegen using internally developed filter materials. All cartridges were evaluated within a blind study framework to ensure objective comparison.

All cartridges shared standardized form factors, and testing followed ISO 16889 for static evaluation and ISO 23369 for cyclic flow assessment. Key performance metrics evaluated, included: differential pressure evolution, contaminant concentration profiles, particle removal efficiency, micron rating stability over filter life, and Dirt Holding Capacity (DHC).

Results demonstrate that ...