The Niro VIBRO-FLUIDIZER® is a vibrating fluid bed of the plug flow type.
A powder layer is vibrated on an air distributor plate. The effect of this vibration combined with the upward and forward directed flow of air through the plate creates ideal processing conditions and powder transport. The unit operates with a shallow powder layer of less than 200 mm. This gives a much more lenient powder treatment, since powder residence times are shorter than in non-vibrating fluid beds which operate at much deeper powder layers.
The VIBRO-FLUIDIZER® is successfully used on all types of powders, agglomerates, and granulates, especially those which fluidize poorly due to a broad particle size distribution or highly irregular particle shape, or require relatively low fluidization velocities to prevent attrition.
The VIBRO-FLUIDIZER® can be operated as a separate drying or cooling unit. It is often associated with a spray drying system to produce agglomerated instant powder or act as a powder conditioning plant for special coating operations.
The VIBRO-FLUIDIZER® has an air distributor plate welded directly to the fluid bed housing. The air distributor plate design is selected according to the product application, but all plates feature special directional perforations that secure lenient powder handling, ability to handle fat containing powders, and achieve a self-emptying characteristic.
Even and stable distribution of the fluidising air is a prerequisite of sustained operation. Niro has developed its own patented distributor plates to obtain optimum fluidization and powder movement during operation and to prevent powder penetration through the plate on plant shutdown.
Another important design feature is the absence of any cavities in the structure. There is no possibility of product penetration through cracks etc. into areas, which cannot be cleaned and inspected. This is very important in complying with a truly sanitary design.
The VIBRO-FLUIDIZER® is equipped with cleaning-in-place nozzles. For products rated as combustible, fire extinguishing systems can be installed. Rotary valves used on the VIBRO-FLUIDIZER® either at the product inlet or outlet are available in standard, sanitary or explosion-proof models.
The BUBBLE PLATE is the latest development by Niro in food grade fluid bed technology. It is non-sifting, i.e. does not allow heat sensitive products to fall through the plate perforations. The plate controls powder movement by means of the airflow. It has no surface imperfections and has been accepted by USDA.
The stiffening T-profiles, used internally where the plates are welded on to the VIBRO-FLUIDIZER® wall housing and externally around the housing, comply with the radii requirements of the 3A standards.
The fully welded air distributor plate of 2 mm is supported underneath with stiffening profiles of special design according to sanitary requirements.
The VIBRO-FLUIDIZER® is constructed by means of supporting profiles that allow for inspection to ensure fully sanitary operation.
The VIBRO-FLUIDIZER® series has been designed to meet the needs of the new millennium, where hygienic operation is paramount. It complies with American 3A and other national sanitary standards.
The VIBRO-FLUIDIZER® can be supplied with built-in atomizer nozzles for rewetting powders to an agglomerated or granulated form. Subsequent drying or cooling takes place in the fluid bed.
A special 'tiltable' version, where the upper part of the process chamber can be opened for exchange of air distributor plate and/or separate cleaning.
Non-vibrating designs are available for special applications.