Chapter 6 Adjustment Procedures
6-10 750-177
Because of variation in oils, including chemical content,
source, blends, and viscosity characteristics, the temperatures
and pressures listed in Chapter 5, and mentioned in the
adjusting of the controls in the following paragraphs, will
vary and thus may be regarded as tentative and to be changed
to provide best firing conditions. Review of the applicable
maintenance instructions given in Chapter 8 will aid in
maintaining an efficient fuel system.
T. FUEL OIL COMBUSTION
ADJUSTMENT
After operating for a sufficient period of time to assure a
warm boiler, adjustments should be made to obtain efficient
combustion.
Burner efficiency is measured by the amount or percentage of
O
2
present in the flue gas. O
2
readings determine the total
amount or excess air in the combustion process, above the
point of stoichiometric combustion or perfect combustion.
Stoichiometric combustion however, is the reference point
used when setting fuel/air ratios in a boiler.
PER CENT O
2
IN FLUE GAS PER CENT CO
PER CENT EXCESS AIR
1020
3040
5060
5
6
7
8
9
10
11
12
1122334455 6
67
890
PER CENT CO
2
IN FLUE GAS
Figure 6-7: Flue Gas Analysis Chart for Natural Gas
FIRST VISIBLE TRACE OF STACK HAZE
1/10 of 1% CO = 1,000 PPM
15
Figure 6-8: Gas Train With High and Low Pressure
Switches
Pressure Switches
To Next Page
Loading...
