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During a 30-minute cycle the system automatically performs the following steps:
1. The waste is loaded into the sterilization vessel, the lid is locked and the cycle is started by pushing a button.
2. The rotor starts spinning slowly and shredding waste, temperature starts rising.
3. The rotor starts spinning faster, the temperature starts rising sharply and the waste is finely shredded
4. At 96-100°C the temperature stops rising until all the water present in the waste has completely evaporated.
5. After the water has completely evaporated, the temperature starts rising again sharply up to 150° C.
6. Water is introduced into the system to wet the material and cool it down to 95°C .
7. The sterilization cycle is complete. The material is unloaded into the collection bins by an air-assisted system.
The vapours released during liquid evaporation are treated by a filter block consisting of 1 absolute filter and 4 charcoal filters. Water and condensable gases are discharged in the sewer system as they fully comply with the limit values set by the current legislation.
During the cycle, plastic and waste are turned by the high temperature into small size grey-brown granules.
During the cycle three processes take place simultaneously to guarantee effective sterilization, namely
• Thermal decomposition of proteins by reaction with water
• Break-up of cell membranes
WATER - PROTEIN REACTION
NEWSTER 10 high-speed rotor heats waste thanks to a high-speed rotor which generates shocks and friction, while also disintegrates and stirs the material inside the vessel.
The shocks and friction produce diffused heat and according to the rules of physics induce compressive deformation affecting the vibrational movement of molecules and, therefore, their temperature.
The parts affected by deformation receive the kynetic energy lost by the element which generated the shock.
As the material is reduced to particles by the rotor, the deformation induced by shocks affects the entire mass of each particle. Therefore, particles are heated to their core unlike in autoclaves where only the outer surface is heated.
Once the sterilization temperature is reached, the material is cooled down by automatic water sprinklers controlled by a temperature sensor.
The water spayed into the vessel is first absorbed by the material which becomes wet and then immediately evaporates subtracting energy. This wetting/evaporation action is repeated at regular intervals every few seconds throughout the cooling step. Therefore, reagent "water" is present here in two physical states, i.e. liquid water and steam.
RUPTURE OF CELL MEMBRANES
In autoclaves steam does not exert mechanical action on microorganisms because their inner pressure is almost the same as the steam pressure. Instead, the Newster® system produces mechanical action leading to membrane rupture and, therefore, death of microorganisms.
The converter performs several short cycles at high temperature sparkling water into the vessel , which is absorbed by the dehydrated material. The high temperature inside the vessel turns liquid water into steam, which increases the inner pressure within the cells. The increase in pressure produces steam inside the cells which literally explode. This mechanical action causes microorganisms to die simoultaneously and regardless of their number.
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