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392 Lawrence K. Wang et al.

2. The flow rate of flue gas leaving the catalyst bed, Q
fg,a
3. The catalyst bed volume, V
bed
Solution
1. Use Eq. (6) to determine Q
com
Q = 20,000 scfm
e
Q = 0 (because h < 15 Btu/scf)
d e
Q = 20,000 + 179 + 0
com
Q = 20,200 scfm (rounded to three places)
com
2. Use Eq. (8) to determine Q
fg,a
Q = Q = 20,200 scfm
fg com
T = 1000ºF
co
Q = 20,200 [(1000 + 460)/537]
fg,a
Q = 54,900 acfm
fg,a
3. Use Eq. (9) to determine V
bed
Q = 20,200 scfm
com
SV = 30,000 h −1 (Table 4)
V = 60 × 20,200/30,000
bed
V = 40 ft 3
bed
Example 10
Describe the methodology used for evaluation of a catalyst incinerator’s permit application.
Solution
Compare the calculated values supplied by the applicant using the following table. If the
calculated value for h , Q ,Q , and V differ from the applicant’s values, the differ-
f e com bed
ences may be the result of the assumptions involved in the calculations. Discuss the details
of the design and operation of the system with the applicant.
If the calculated and reported values are not different, then the design and operation of the
system can be considered appropriate on the assumptions employed in this handbook.

Comparison of Calculated Values and Values Supplied by the Permit Applicant
for Catalytic Incinerator
Calculated value Reporte value
Continuous monitoring of combustion temperature — —
rise and pressure drop across catalyst bed
Supplementary fuel flow rate, Q — —
f
Dilution airflow rate, Q — —
d
Flue gas stream flow rate, Q — —
com
Catalyst bed volume, V — —
bed
NOMENCLATURE
ε Combined motor fan efficiency (dimensionless) (approx 60%)
C
p air Mean specific heat of air (Btu/lb-ºF)