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constant (or small deviations could be observed) – the flue gas temperature, the
thermal capacity, the flue gas emissions. However, the boiler is manually fuel
fed boiler, so small deviations could be observed (according to the frequency of
fuel charging rate, as well as the fuel quality and quantity).
EXPLANATION: the optimal condition of the boiler’s operation is achieved at
temperature of the circulating water in the range of 65 - 85
o
C. In this
temperature range the boiler operates in optimal thermal condition and the
wood gasification process is easy controlled, as well as high efficiency of the
combustion process. In case the heating system is equipped with circulating
pump, the operation of this pump should follow the above mentioned
requirement, i.e. it should operate at temperature of the circulating water above
65
o
C. In case the boiler operates at temperature levels below this point (65
o
C),
the operation will lead to intensive tar deposition and decreased heat transfer
rates, as well as chemical corrosion, which both decreases the efficiency and the
reliability of the unit;
In nominal operation mode the boiler, as well as the heating system should
be commissioned (i.e. the so called “hot tests” should be done), considering the
requirements and legislations.
NOTES:
•
In case that the heating system is equipped with circulating pump, which
transfers the heat energy from the boiler to the heating system, the return
flow (the cold flow) temperature should not be below 60
o
C, because there
is great chance to achieve local cooling of the flue gases in the boiler,
which will lead to intensive vapor condensation and will be followed with
chemical corrosion of the heat exchanging surfaces;
•
It is not recommended to operate the boiler at thermal capacity below the
minimal one, depicted in the operating range of the unit, as such regimes
are low efficient and decrease the reliability of the boiler. Such low
thermal capacity conditions could lead to conditions, which will result in
decomposition and failure of some components of the boiler, also could
lead to life threatening conditions as well (mainly carbon monoxide), as
well as tar, which will deposit condensation on the internal surfaces of the
boiler and corrosion will follow;
•
In case the boiler should operate at thermal operating mode, which is
below its nominal thermal capacity, it is highly recommended to install a
heat accumulator, in order to allow efficient and economic operation of
the boiler and flexible operation of the heating system. The heat
accumulator tank serves are energy depot, i.e. it accumulates the
excessive heat energy during nominal operation of the boiler and the
