eta 13180LP-T, Operation

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Information on fuel
79
7 Information on fuel
When the fuel causes slag
If pieces of slag are found in the ash box, the cause
often lies in the flue gas recirculation. For this reason,
clean and check the flue gas recirculation.
An excessive flue draught can also cause slag by
reducing the effectiveness of the flue gas recirculation.
If the flue draught is over 15 Pa, a draught limiter is
required. Or a nozzle on the chimney opening, with
which higher exit velocities and better lift for the flue
gas are achieved.
The fuel may have an excessively high ash content.
Therefore, the boiler must be de-ashed more often.
Shorten the de-ashing interval by 50% if slag occurs.
The boiler then performs twice as many de-ashing
runs. Refer to chapter
5.2.2 "Text menu - Adjustable
parameters" .
Also leak air from a poorly sealed combustion chamber
door, heat exchanger cover, ash box, maintenance
cover... causes slag. Ensure that they are closed and
their seals are in order.
Keep an eye on the quality
The composition and characteristics of pellets are
standardised, but not legally regulated. To heat with
minimum possible maintenance, demand certified
quality in accordance with the applicable current
standards from your pellet dealer.
Delivery quality also includes the last link in the
transport chain, blowing the pellets into the storeroom.
The pellets should not fly too fast or too slowly; they
should strike the impact protection mat gently and not
be pulverised.
A reference value for an acceptable injection time
is 4 to 5 minutes per ton. In no case should the
pellets be injected more quickly.
Solid and with little dust
The pellets must be solid enough that they do not dis-
integrate to dust during transport, injection into the
store or suction from the store to the boiler. High dust
content hinders combustion and results in more ash in
the flue gas.
The inclusion of small amounts of natural bonding
agents, such as maize starch or molasses, improves
the transportability of the pellets and keeps their dust
content to a minimum.