Operation – Toaster:
- Cereals to be toasted, roasted, puffed and/or dried are fed onto the oscillating conveyor which holds and transports the product below multiple tubes. Ambient air is heated using twin gas burners in specially designed and constructed combustion chambers.
- The heated air from the fan travels to the pressure plenum area, then passes down through the distribution tubes onto the oscillating conveyor, creating a bed of air under the product. The air movement engulfs each particle, and this guarantees continuous uniformity of toasting and drying.
- The exhaust air rises vertically from the conveyor around the tubes and exits via slots into the return ducts. The air is then passed through cyclones where airborne particles are removed and discharged through rotary airlocks.
- An amount of the process air is exhausted continuously in order to avoid moisture build-up in the system.
- The balance is then reheated to the correct temperature by the burner as it again moves to the fan. The recycle system ensures maximum heat utilisation, hence yielding a very efficient operation.
- Product changing and aseptic cleaning are extremely simple and fast, as the oscillating conveyor has no holes where the product could build up.
- The toaster is well insulated – with an insulating material (mineral wool) rated for temperatures as high as 350°C – and clad with stainless steel sheeting.
- Because of its unique design, the Drytech ‘Kontraflo’ toaster can operate efficiently down to approximately 35% of design capacity.