- The centrifuge system is coupled with the conical dryer, the wet cake from the centrifuge machine is dropped directly into the dryer in a totally enclosed condition.
- The system is ideally suitable for toxic and hygroscopic products, sterile and USFD approved plants.
- As both the operations are performed in separate equipment (Centrifuge and Dryer respectively); the system has a distinct advantage over filtration + Drying Systems.
- The inner wall of the cone is connected to a heating arrangement and is insulated from the outer wall. The agitator picks up the wet/semi-wet cake from the center and pushes it to the periphery.
The Drying vessel is mounted on a lifting & swiveling column. It is connected to the centrifuge by means of a special double value system. The active part of the valve is mounted on the centrifuge & the passive part of the vessel. This allows the drying vessel to be removed from the centrifuge totally closed & isolated.
After the product is discharged into the drying vessel, the vessel is lifted to the frequency-controlled power station. The vacuum and the heat utilities are then connected, and the drying process can be started according to drying characteristics of the product by controlling both the agitator speed and jacket heat.
After drying, a stainless-steel barrel is connected to the vessel with the same type of double valve used between the centrifuge and vessel, so that the product can be discharged in a totally isolated manner. The cleaning of the vessel is done filling with washing solution & agitating at high speed. The vessel can be inspected by opening the cover
Main Process Vessel (Cone) The dryer main process vessel is conical in shape, with the inside wall being a polished surface. The outside of the shell is provided with heating the surface. Over this is an insulation jacket that ensures that the heat transfer is only in one direction, i.e. only on the main shell.
Dryer Top Cover
The dryer top cover is hinged type openable cover and provided with insulation jacket. The cover is provided with light and sight glass flanges, Product input (Feed) nozzle having a flanged connection, vacuum filter assembly and pad flange for bearing housing agitator assembly. The inside of the cover is polished, suitable for cGMP standards. The cover is provided with hinge plates and pin with counterbalance spring unit for the ease of opening manually, without any mechanized device.
Agitator & Bearing Housing Assembly
The dryer is provided with an agitator assembly consisting of a shaft and spiral blades. The spiral blades are provided throughout the process area of the dryer. The spiral blades are designed so that during rotation it has a minimum clearance between the blades and vessel wall. The rotational action of the agitator picks up wet powder from center and splashes on the sidewall of the vessel, which is heated by the heating media. In this manner, the product is dried. The shaft is supported by taper roller sealed bearings. The shaft entry inside the dryer vessel is provided with cartridge type mechanical seal assembly for leak proof sealing.
The filter assembly is provided on top of the dryer cover. During drying operation, a vacuum is applied inside the vessel through this assembly. The vacuum assembly is provided with specially designed filter bag holding cage, so that, when vacuum is applied the dried particulate do enter into vacuum stream and product loss is completely avoided. The bag assembly is a quick openable design, thus after every batch, the filter bag can be replaced or removed for cleaning purpose. In this manner, it fulfills the cGMP and USFDA requirements of batch contamination or mixes up.
Drive: The dryer agitator assembly is driven by electric motor, mounted on the top of the shaft. The motor is driven by AC inverter variable speed drive to vary the speed of the agitator as per the process requirements.
Product out-put flange & other assemblies
The dryer bottom flange is provided with product out-put flange to fix product discharge valve. The valve can be fitted between flanges. The output flange is provided with nitrogen purge nozzles to flush the dried product after discharge.
Seals and Gasket
All the process contact gaskets and ‘O’ rings for the centrifuge and dryer are PTFE encapsulated Viton or silicon rubber to give longer sending sealing life. Also, these ensure zero-contamination, as PTFE withstands almost all material and higher temperatures.
|Technical Specification||Centrifuge Model|
|Max. Rotation Speed||rpm.||23193||18384||14702||11749|