4.3
HEAT – THE FLOW THROUGH SYSTEM
The information about obtaining temperatures and the biological process in this manual
constitutes no guarantee to do so by the manufacturer or distributor.
Oxygen
+ Carbon and Nitrogen (C:N) + Heat + Moisture
→
in balance.
The temperature inside the heat zone will keep 50-65°C due to the biological process. The machine
can be equipped with a heater so that the incoming air always keeps >10°C. The Big Hanna is using
a flow-through system. Food waste is fed into the front gable and when entering the cylinder is
pushing the material already inside forward. At the first 1/3
rd
of the cylinder the material goes
through the thermophilic phase where the temperature and moisture content is high. In the
following phase most of the reduction is taking place and the maturation at the end will ensure
that the material is fully composted when leaving the cylinder. The compost that comes out of the
Big Hanna is not as biologically active as it would be if it had only gone through the first
thermophilic phase.
1.
Fresh food waste and sawdust/pelletised sawdust is fed into the Composter.
2.
Thermophilic phase – 40-70% moisture. High temperature : 50-65ºC.
3.
Mesophilic phase – Lower moisture. Temperature: 25-45ºC
4.
Maturation phase – Low moisture. Temperature: 20ºC.
5.
Compost is automatically emptied from cylinder.
The waste material is put in at the front of the composter and the temperature is raised in the
material quite fast. At normal filling level (60-70% of the cylinder) the hot-zone should be placed
between the front and the first inspection door on the cylinder. At normal filling level the
temperature will be 50-65
o
C.