Metal-Fach GHT, Operation And Maintenance Documentation

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i.e. pressed into a cylindrical shape. The raw material is stored and transported in perfectly dry
conditions. The plant operator must also store the pellets in a perfectly dry place. This is the
only way to guarantee correct and efficient combustion.
Requirements for wood pellets
For combustion in the
GHT
boiler, wood pellets with a diameter of 6 mm and a length of 3.15
to 40 mm should be used. 1% of the wood pellet can be longer than 40 mm, but not longer than
45 mm. The residual moisture content may be up to 10%. Wood pellets intended for combustion
in the
GHT
boiler must meet the requirements of EN ISO 17225-2.
Quality characteristics of wood pellets
Good quality wood pellets:
■ smooth, glossy surface
■ even length
■ low dust content
■ in the water it falls to the bottom
Poor quality wood pellets:
■ cracked, rough surface
■ large length differences
■ high dust content
■ floats
1.4.4 Minimum fuel requirements.
Ingredients
When buying wood for combustion, choose wood that does not contain other elements (e.g.
stones, metal parts, mortar residues, plastics, etc.). They change the composition of the material
to be burned and thus the basic parameters of the combustion process. For all types of fuels, the
rule is that they must not contain foreign bodies such as metal parts, stones, fragments of masonry
or plastics.
Do not exceed the following limits (per kg of dry fuel) for non-flammable components (ash when
analysed at 815°C).
The consequence of exceeding the above limits is a shortened service life of the combustion
chamber and solid fuel boiler. As a result, the workload associated with maintaining the unit in
good technical condition increases and the intervals between maintenance intervals are
shortened.