CTC Tea is mainly blacktea in which the leaves are passed through a series of cylindrical rollers with hundreds of sharp teeth that crush, tear, and curl the tea into small, hard pellets CTC teas are produced by conventional methods of withering, rolling, fermentation, drying, sorting and finally packing.
To begin with withering, there are various machines available like:
- Withering Troughs: To ensure good withering this machine consisting of one axial flow fan, ducting with air controlling damper and a long tunnel covered with wire mesh.
- Axial Flow Fans: This aero-dynamically designed machine ensures uniformity of withering.
Rolling: After achieving satisfactory wither, the leaf gets ready for rolling. The machines used here are:
- Rotary Granulator/ Ghoogie: It generally has a central shaft rotating on bearings on pedestals cemented on the floor and holding the Stainless steel or Aluminium cylinder on spokes from the central shaft.
- Leaf Sizer: Leaf Sizer is a cylinder in which the main shaft has knives (blades) which rotates at a speed of 2500 rpm and is used for shredding tea leaves.
Fermentation: It is one of the most important steps in determining the quality of tea. The machines used are :
- Single/ Double Stage Continuous Fermenting Machine (Belt / Tray): Theaerodynamically designed air duct facilitates uniform distribution of humidified air at 95% RH and checks hygiene.
- CFM Auto Controller: Similar to the previous machine this new and automated CFM machine ensures energy saving.
The machines used for drying are:
- Vibratory Fluid Bed Dryers (VFDB):This machine helps in the manufacturing of best quality tea as it is fitted with an efficient fiber extraction cyclone system and Dust extraction & re-firing system.
- Tray Type Conventional Dryer / ECP Dryer: It has high moisture evaporation capacity.
Sorting plays an important role in CTC tea. The machines used are
- Auto Batch Weigher: It ensures accurate and reliable weighing of tea from the dryer mouth.
- Slow Speed Fibre Extractor: Slow speed fibre extractors cum tea sorters eliminate rubbing effects and ensure clean tea without any loss of bloom.
- Vibro Screen Sorters: The machine ensures a continuous flow of production without any need for resorting.
Following these traditional steps comes the basic steps of grading and sorting, which is almost common to all kinds of tea.