The mostly extensively used and most general process of tablet research is the wet-granulation technique. Its reputation is suitable to the superior prospect that the granulation will get together all the substantial desires for the solidity of high-quality tablets. Its chief disadvantage are the numeral of disconnect steps disturbed, in addition to the instance and labour necessary to take out the process, particularly on a huge scale. The steps in the wet system are weigh, combination, wet massing, programme the moist mass, dry screening, drying, lubrication, and compression. The paraphernalia concerned depends on the magnitude or size of the consignment.
Wet massing can be perform by:
- Low Shear mixers/granulators,
- High Shear mixers/granulators,
- Fluid-Bed granulators/Tray dryers,
- Spray Dryers, or
- Extruders and Spheronizers.
Tray Dryer Working Principle:
- In tray dryer hot air is incessantly dispersed. Strained convection heating takes place to eliminate the moister from the solids located in trays.
- Simultaneously the damp air is separate moderately.
- Damp solid is overloaded in to the trays. Trays are located in the compartment.
- Clean air is introduced from side to side in left, which pass from end to end the heaters and gets heated up.
- The hot air is dispersed by means of fans at 2 to 5 metre per second.
- Disorderly flow lowers the biased vapour pressure in the ambience and also reduces the thickness of the air border layer.
- The water is chosen up by the air. As the water evaporates from the exterior, the water diffuse from the interior of the solids by the vessel act.
- These proceedings happen in a solitary pass of air. The time of get in touch with is short and quantity of water chosen up in a solitary pass is diminutive.
- Therefore the discharge air to the melody of 80 to 90 % is dispersed reverse from end to end the fans. Simply 10 to 20% of fresh air is introduced.
- Damp air is discharge through opening. Thus stable temperature and standardized air flow over the equipment can be maintained for achieve consistent drying.
- In case of the wet granule as in tablets and capsule ventilation is continued until the wanted moister satisfied is obtain.
- At the conclusion of the aeration trays or trucks are pull out of the compartment and taken to a tray removal position.
Tray Dryer assembles structure & stipulation:
The Tray dryer have to be of vigorous manufacture built on produced angles of 3mm+ thick sheet and properly durable with angle and section.
The dryers’ exterior walls have to be manufactured from 1.6mm thick SS sheets of 316 qualities or additional.
The interior of the dryer is built of 1.6 mm thick superiority sheets. The interior arrangement should be completely TIG weld and all the internals have ground smooth surface.
It must be insulate with least amount of 50 mm thick glass wool lagging and Cladded with SS refined sheets.
The dryer ought to be having a clean air inlet from side to side 20 Micron PP cloth filters and an adaptable air opening flap and a door at the frontage. The door is detonation evidence and is protected with the assist of mechanism loaded ball latch with appropriate pressure. Door lips are having Neoprene rubber Gasket to prevent leakage.
The plan and construct of the dryer is of high criterion of GMP and has an aesthetic look. It is polished superficially to 150 grit matt finish and inside polished to 220 grit mirror finish.