Wet separators are specialist filtering systems used wherever sparks fly in machining processes and wherever combustible, explosive or sticky dust is created. They purify the atmosphere by feeding the contaminated air through a fine screen of water and then separating out the droplets containing impurities in a centrifugal force filter. The use of water also reliably prevents any explosions of ignitable dust. Yet this technology, which has proved its worth for decades, has now reached its limits. "These universal systems do not always meet current requirements with regard to energy efficiency, separation efficiency and ergonomics," says Ulrich Stolz, head of the Technical Department at Keller Lufttechnik, based in Kirchheim unter Teck, Germany. "Conventional wet separators cannot meet the level of separation efficiency required for clean air recirculation and at the same time deliver ecologically sound results. The residual impurities are too high in some instances, which is why these systems cannot be operated with direct recirculating air operation."

Keller Lufttechnik is thus at EMO HANNOVER 2017 (September 18-23) to unveil the new HydronPlus, whose hybrid technology brings together the advantages of wet and dry separation. "The HydronPlus combines the explosion protection benefits of a wet separator with the excellent separation efficiency of a dry separator," explains Leopold Rang, head of Systems Engineering. "A wet separator is followed by a secondary filter stage, ensuring that the purified air falls far below the set limit values for particles as defined in workplace regulations and VDI standard 2262 Sheet 3 and can be recirculated back into the production plant." Model calculations by Keller Lufttechnik indicate that approximately EUR 2,000 in annual savings on heating costs can be achieved using a HydronPlus in two-shift operation.