Continuous Dryer-Screener System

The circular fluid bed dryer is half the size and weight of a rectangular fluid bed dryer of equivalent capacity, and allows all primary system components to be consolidated on a shippable frame.

Inherent strength of the circular processor eliminates the need for heavy-gauge walls and cross braces otherwise required to withstand continuous vibration, allowing vibratory motors to be downsized. The circular unit also requires only one air inlet and outlet and has fewer weld seams, reducing overall size and construction cost, especially when finished to 3-A, FDA, and BISSC sanitary standards.

Cleaning time is cut by more than 50 percent due to the reduction in interior seams, and accessibility afforded by a quick-disconnect housing.

Material fed into the top inlet of the dryer descends into the fluid bed chamber where it vibrates on a circular screen within a rising column of heated air ducted into the bottom of the chamber from the upstream heater/blower. The continuous airflow, and vibration induced by two vibratory motors and spring suspension, separate and fluidize individual particles, maximizing surface area and drying efficiency. The vibratory action also causes material to travel from the center of the screen to a discharge spout at the screen's periphery in controlled spiral pathways on a first-in-first-out basis, ultimately discharging dried material into the top-center inlet of the circular vibratory screener.

An imbalanced-weight gyratory motor positioned beneath the chamber of the screener vibrates two screening decks. Oversize particles travel in controlled spiral pathways from the center of the screen to a spout at the screen's periphery where they are discharged for reprocessing.

On-size and undersized particles pass rapidly through the top screen to a bowl-shaped feed tray that directs them to the center of the second screen. On-size particles travel in controlled spiral pathways to an extended spout at the screen's periphery, into a bulk bag, while undersize material passes through the screen onto an integral metal chute and through a third spout for reprocessing.

The circular fluid bed processor is available in diameters from 18 to 84-inch (460 mm to 2135 mm), and the circular vibratory screener from 18 to 100-inch (460 mm to 2540 mm), for low-capacity laboratory and pilot plant testing to high-volume drying and/or screening on a batch and continuous basis.