The Comber Pressofiltro PF series Nutsche filter dryer from Heinkel USA, Swedesboro, N.J.,is a versatile unit designed for multi-purpose production facilities to meet the demanding requirements of filtration-separation and drying.
Designed to meet a wide range of stringent cGMP and FDA guidelines, these units are built with clean-in-place systems to achieve good cleaning and permit optimal inspection after the cleaning process. All product contact wetted surfaces are designed without dead areas with smooth transitions of internals and without any bolted connections. For good access to the filter internals for cleaning and inspection purposes, the filters are equipped with an opening filter base.
The agitator is supported from the top with the agitator drive, bearings and shaft seal. Shaft sealing is with a double mechanical seal and convoluted bellows. The agitator arms with specially designed bottom teeth smooth and press the cake when rotated counter-clockwise, and mix and agitate the cake when rotated clockwise. Simultaneous rotational and vertical agitator motions result in a very efficient and even mixing of the entire product mass for mixing and drying.
TheagitatorarmsareS-shaped for improved product discharge. Plus, all product wetted surfaces are heated to obtain the largest possible heat exchange area for short drying times and a low attainable final moisture levels. Supplemental microwave heating is available to further reduce drying times.
Product is discharged through a hydraulically operated side discharge valve, with the valve plug contoured to match the curvature of the vessel internal wall. The solids discharge valve is a metal-to-metal seal design with the sealing surfaces arranged outside the product flow path. Alternatively, the product can be discharged through an active or passive isolator (glove box). On smaller filter units, the isolator permits contain sampling, product discharge and heel removal all in one system.