Dresden is home to the largest whisky distillery in Germany. The plan is to produce up to one million bottles of the single-malt brand “Hellinger 42” in the Saxon capital every year. Dresdner Whisky Manufaktur GmbH decided to collaborate with Ziemann Holvrieka GmbH to realize its wort preparation process. The dynamic mash filtration system Nessie by Ziemann, in combination with the grist mill T-Rex by Ziemann, was ordered as a critical technology for the first time by a spirits producer. The design of both innovations differs fundamentally from conventional process technology, which offers the user many advantages.
Looking back, Jörg Hans, Production Manager and Managing Director of Dresdner Whisky Manufaktur explains why the whisky producer decided to pioneer these product innovations: “On the one hand, we were convinced by the technology and the supplier. On the other hand, we were extremely limited in terms of space. There simply would not have been space for other machines.”
Four rotary disk filter modules as standard
The standard version of Nessie consists of four rotary disk filter modules with a diameter of one meter, which are arranged in a row on a common frame (see Nessie illustration). The mash flows through modules 1 to 4, one after the other, with the wheel segments rotating in the direction of flow. The mash transport is supported by gravity, which results from the cascade arrangement of the modules.
The retention time of the spent grains in the module can be influenced via the speed of the wheel pairs. In the default setting of 8 rpm, an idealized mash particle takes around three minutes to pass through the four modules. However, the speed can be set individually for each module. The retention time can therefore be regulated depending on the process and stage.