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TECHNICAL PASSPORT. INSTALLATION and OPERATION MANUAL
TECHNICAL PASSPORT. INSTALLATION and OPERATION MANUAL
Diagram 4. Design of fuel hopper FH 500-V2
3. FUEL
All pellets are biomass manufactured
from common low-growing plants and
trees. The most common household type
pellets are made of sawdust and milled
wood chippings which are waste material
from wood used in the production of logs,
furniture and other products. Wood is the
richest raw material which does not have
any impact on the production costs of
food products or ethyl alcohol (ethanol).
The raw material is processed under high-
pressure and temperature and is pressed
to produce small-size cylindrical pellets.
The production process may utilize soft
wood material (such as softwood, pine),
hardwood (oak) as well as recycled waste
wood. Wood pellets are produced in
hammer mills or wood pellet plants.
Advantages of wood pellets:
Convenient storage.
Pellet bags can be stored on a small area
in a dry garage, basement, service room
or shed.
Easy loading.
In most cases the boiler hopper needs
loading only once a week – this depends
on the hopper capacity.
Better control of fuel quantity.
The small size of the pellets allows
for precise fuel feeding. On the other
hand, the supply of air for reaching
optimal combustion efficiency is easier
to adjust since the fuel quantity in the
combustion chamber remains constant
and predictable.
Fuel efficiency.
High combustion efficiency is also
determined by consistently low moister
content of pellets (consistently under
10% as opposed to 20% to 60% moisture
content of the logs). Low moisture
content, controlled fuel portions and
precise air setting means high combustion
efficiency and very low carbon oxides in
the flue gases.
