Roto Cone Vacuum Dryer

For such low temperature drying, vacuum application and integrity of the equipment has to be maintained by ensuring that all joints, nozzles and openings are leak proof. All joints for nozzles should be of the male-female lip arrangement.

The Rotary vacuum Dryer is mounted on two structural stands with the help of heavy bearing blocks designed to bear the self weight of the equipment and the product weight. The product is charged into the equipment through vacuum transfer or physical dumping of the product from the manhole. Two specially designed hollow shafts support the Roto Cone Vacuum Dryer.

Drying takes place when vacuum is applied from one side hollow shaft and steam is passed into the jacket under controlled conditions through the other side hollow shaft. To preserve the integrity of vacuum while mixing, a mechanical seal is provided. Steam is connected to a rotary joint through which the condensed steam in the form of water is taken back. The RCVD is rotated at a RPM of 5 - 20 depending upon the capacity.

High Vacuum is applied through a receiver further connected to a condenser and a cyclone separator. The cyclone separator ensures that any fine products which does not get entangled in the internal filter is separated and only the vapour laden air is passed through into the condenser. The Condenser condenses the vapour passing through. The receiver collects the condensate, which is generally expensive, and environment harmful solvents.

As the Roto Cone Vacuum Dryer is generally operated under high vacuum conditions, the above solvent separation arrangement ensures that no harmful or corrosive solvents enters the High Vacuum Dry Screw Pump.

An insulation cladding with mineral wool or PUF is provided around the jacket to stop heat dissipation. In GMP models the entire insulation cover is of welded SS sheets and polished to a neat finish.

The equipment is rotated with the help of a girth gear connected to a suitable speed reducing gearbox and motor. Operating speeds are further controlled through an Electronic Variable Frequency Drive placed in a control panel. The control panel houses other controls like the start stop of the main motor, process timer to stop at set period, temperature indicator controller for controlling precise temperatures in the RCVD, digital vacuum indicator, harmonic filters and emergency stop. An additional man safety guard is provided besides the RCVD to ensure that the equipment does not start until it is fixed into place. All standard electrical safety guards like overload protection, single phase preventer, ELCBS, MCCBs are standard parts of the Control Panel.

The internal product contact surfaces are generally polished to 240 grit mirror finish. All weld joints are ground smooth to ensure that there is no product built up. It is very important to ensure that the internal surface is absolutely smooth as the RCVD has got no mechanical scraping devices and the product to be dried may get stuck on the surface and due to heating from the jacket, may get charred.

The RCVD dryer electrical & electronic parts like motors, control panels, sensors, solenoid valves and other instrumentation are of Flameproof Construction with certification from CMRI Dhanbad. Any parts specifically not available in FLP construction are housed in FLP Enclosures.