Honeywell BCU 465 - Flameless Mode to Reduce no Formation

BCU 460, BCU 465 · Edition 11.19 15
Application
1.1.8 Flameless mode to reduce NO
x
formation
VAD
BIC..M
IC 40 + BVH
M
VAS..L
VMV
DG
BCU 465..D2
PZL
Process Control (PCC)
AKT
STM
The burner control unit BCU 465 switches the burner
BIC..M ON/OFF in cycles. Burner BIC..M is controlled
without pneumatic air/gas ratio control system. The gas
supply pressure is controlled by the gas pressure regu-
latorVAD; the required burner capacity is set using the
fine-adjusting valveVMV. The capacity is controlled by
actuator IC40 and butterfly valveBVH. An air pressure
switch upstream of the burner monitors the functioning
of the butterfly valve. In addition, air/gas ratio monitor-
ing for the zone or the furnace is required.
As soon as the safety temperature monitor STM signals
a furnace temperature of ≥850°C (1562°F), the burner
can be switched to flameless combustion (Low NO
x
mode) to significantly reduce NO
x
emissions.
Switching to Low NO
x
mode eliminates the counter-
pressure by the flame in the ceramic tubeTSC. At a
constant gas supply pressure, the gas volume increases
by approximately15%. In Low NO
x
mode, the butterfly
valve moves to a smaller open position tailored to the
pressure conditions.