Rotary Disc Driers
The Wykes Disc Drier is a surface contact drier designed for continuous processing of a wide range of wet solid products encountered in the food, petfood and rendering industries. Wykes Driers are installed in many applications including meat and bonemeal, feathermeal, bloodmeal, brewers grain and also high moisture content sludges. The design ensures optimum evaporation efficiency within a compact unit as a result of excellent contact between the product and rotating rotor disc assembly with high heat transfer rates leading to compact heating surface requirements.
The Wykes range of driers operate by indirect heat transfer from a standard medium, usually dry saturated steam at 6 barg into the product to be dried.
A typical application is the cooking of Animal By Products where unit sizes are available for throughputs up to 16 tonne/h of wet product at 60 % moisture) producing typically 6.5 tonne of dry product. The vapour evaporated is extracted and ideally suited for disposal in a Wykes Thermal Oxidiser which destroys all the odours by oxidation. Alternately, they can be condensed in an Air Cooled Condenser and treated in an effluent treatment plant all of which are also available as standard Wykes products.
The rotor tube is a precision machined shaft, containing a series of outlets along its length over which, individual disc sub-assemblies are accurately located. In operation, steam which is injected into the shaft at one end passes into each disc through these openings which also allow condensate to flow back into the shaft. The condensate is collected from the shaft via a dip tube and discharges through the same end as the steam inlet through a pressure tight rotary joint.
All Wykes driers are constructed from a series of stainless steel discs either 1700mm dia. or 2200mm dia. depending on the size of drier. Each disc is manufactured from BS 1501: Part 3 1990 Grade 304S31 or equivalent stainless steel.
Staybars are positioned within the disc to provide additional strength using a special alignment technique prior to the two halves being automatically welded together.
The discs are sub-assembled and then installed on the rotor shaft to be welded into place.
The rotor shaft is completed by the addition of end stub shafts which are forged, tested and then precision machined to mate and bolt onto the ends of the rotor tube. The end result is a highly efficient rotary disc assembly, that has been engineered to meet the most stringent requirements. The standard rotor discs are designed, constructed and tested to fully comply with BS 5500, the United Kingdom standard specification for welded pressure vessels. All welding procedures and welders are fully tested and approved to the worlds leading standards.
The drier shell is manufactured from 12mm thick grade 304L stainless steel. The upper part of the shell is designed for collecting and transferring the water vapour extraction away from the product. Inspection doors are fitted along the full length of this vapour dome. End flanges are bolted to the shell and these are constructed from carbon steel with a stainless steel lining welded to the inside. This ensures that all contact “wetted” parts are of stainless steel. Access doors are installed in both end flanges.
The heating medium is fed through a rotary joint into the inside of the rotor shaft, from where it is evenly distributed to each individual disc.
The condensate is efficiently collected and discharged through the same end of the rotor shaft.
Scraper bars are fitted between each disc to improve the product flow through the drier and to prevent any build up on the drier heating surface. The drier is driven by a shaft mounted gearbox, powered by a suitably rated motor. A belt driven fluid coupling is fitted between the two units.
The complete machine is supported on two saddles for mounting on the prepared foundations for ease of installation.
Wykes has a long established reputation as a preferred supplier of turnkey projects for the Rendering and Food Processing industries throughout Europe, providing a complete service, from research and development through process design to manufacture, commissioning and full lifecycle maintenance all supported by expert project management. Wykes can design and install a control system to ensure integration into the existing site processes, a vital element for a successful installation.