Dehumidifying leather by Thema31 October 2002
Italian leather drying and conveying specialists, Thema System, have collaborated with another company, Tecnofrigo, to improve their leather drying line. They have introduced a novel mechanism that concentrates on drying the leather itself rather than the air surrounding the material. Together with Tecnofrigo Srl, Thema have produced a patented system for drying leather by recycling the thermal energy and, therefore, lowering the operating costs. The new system encompasses the total recovery of the thermal energy using a device, which Thema call the 'rotating chemical absorber'. The principle is based on the condensation and absorption of the vapour contained within the leather inside the drying tunnel. The air is then reheated to finally dehumidify the leather ready for conditioning and staking. The new system has been incorporated into Thema's Tunnel TH009 and is known as 'Thema Dry Control'. The air extracted during the drying cycle is then automatically reconditioned and recycled into the drying process. As the leather passes through the drying chamber, the moisture content is reduced by 60% by condensation from heating. Following this step, the leather passes through a rotating chemical absorber which lowers the moisture content by a further 10%. Then finally, the leather is passed through a second heated section where the leather is dried down to approximately 10% humidity. The new concept has the main advantage of drying leather in the tannery using less energy than other devices. Hides and skins are able to pass through the drying tunnel on a chain conveyor in the roof space of a tannery building. Thema will also be highlighting their latest loading and unloading device at the Tanning Tech exhibition in Bologna in November.