Combustion Flighting; Operation - ASTEC Phoenix FURY Operation And Service Manual

Combustion Flighting

1. The flight design in the combustion zone of the drum is especially important for minimizing flue gas
pollutant emissions.
2. The flights provide heat shielding to keep the drum skin temperature low. (Protecting the metal drum
skin from the flame radiating directly onto the drum.)
3. For the lowest possible emissions of CO and Total Hydrocarbons, the combustion zone must be clear
of veiling material. (Showering material through the flame is a common cause of incomplete
combustion.)
4. The combustion zone must be large enough to accommodate complete combustion. (The length and
diameter of the combustion zone must be large enough for the burner flame to fit inside. See the
Burner Performance Data Sheets for the flame dimensions.)
5. The combustion flights are designed to be self-cooling, to prevent their failure through overheating.
(A good combustion flight design plows most of the material over the fights, while allowing some to
flow under them next to the shell, insulating the drum from radiant heat, and using the aggregate to
cool the flights.)
6. The ASTEC Parts Department can supply combustion flights designed for your application.

Operation

1. The basic model PHOENIX FURY uses a firing rate control motor mounted to the combustion air
damper which is mechanically linked to the fuel valves and air damper.
2. The Programmable Logic Control (PLC) option to the burner control, adds additional sophistication to
the management of the fuel/air ratio, by adding another control motor that manipulates the fuel valve
position.
3. The PLC allows the fuel and air valve to be controlled independently.
4. A combustion blower pressure switch (normally open) must be made to prove the blower is operating.
This pressure switch is usually set at 1.5" w.c.
5. The combustion air control damper must open to initiate the purge cycle prior to lighting the burner.
a. The safety limit parameters must be satisfied.
b.
The purge pressure switch must be tripped for the purge cycle to begin. This pressure switch is
usually set at 10" w.c.
c. The plant flue gas exhaust fan must be confirmed to be running.
d.
The fan damper must be open enough for the calculated volume of air to flow during the required
purge time.
e.
The minimum purge time is the time required for four volumes of air to flow through the heating
chamber
5.
Before light-off the combustion air damper must be at the low-fire position.
6.
The low-fire combustion air damper limit switch is set to close its contacts at the minimum fire light off
position.
7. The low fire proof fuel valve limit switch (the switch that contacts the fuel valve linkage arm) must be
closed with the low fire combustion air switch for the light-off sequence to begin
Phoenix FURY - Operation and Service Manual
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