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358 Lawrence K. Wang et al.

calculated and reported values for Q will be dependent on the differences between
fg
the calculated and reported values for Q and Q . If the calculated values for Q and Q
d f d f
differ from the reported values for these variables, the differences may be the result of
the assumptions involved in the calculations. Therefore, further discussions with the
permit applicant will be necessary to find out about the details of the design and
operation of the proposed thermal incinerator system.
If the calculated values and the reported values are not different, then the design and
operation of the proposed thermal incinerator system may be considered appropriate
based on the assumptions used in this handbook.
Table 7 presents a HAP Emission Stream Data Form generally required for the
permit applications.

5.2. Operations and Manpower Requirements
Electricity costs are associated primarily with the fan needed to move the gas through
the incinerator. Equation (8) can be used to estimate the power requirements for a fan,
assuming a fan motor efficiency of 65%. The fan is assumed to be installed downstream
of the incinerator, as shown in Fig. 2.
P HRS)
×
.
F = 181 10 −4 Q ( fg a)( )( (8)
p ,
where F is the power needed for the fan (kWh/yr), Q is the actual flue gas flow rate
p fg,a
(acfm), P is the system pressure drop (in. H O [from Table 5]), and HRS is the operating
2
hours per year (h/yr).
Operating labor requirements are estimated as 0.5 h per 8-h shift. Supervisory costs
are estimated as 15% of operator labor costs. Maintenance labor requirements are esti-
mated as 0.5 h per 8-h shift, with a slightly higher labor rate reflecting increased skill
levels. Maintenance materials are estimated as 100% of maintenance labor.
Indirect annual costs include the capital recovery cost, overhead, property taxes,
insurance, and administrative charges. The capital recovery cost is based on an estimated
10-yr equipment life, whereas overhead, property taxes, insurance, and administrative
costs are percentages of the total capital cost (31).
Most operational problems with thermal incinerators are related to the burner.
Typical problems encountered include low burner firing rates, poor fuel atomization
(oil-fired units), poor air/fuel ratios, inadequate air supply, and quenching of the burn-
er flame (6). These problems lead to lower DEs for HAPs. Symptoms of these prob-
lems include obvious smoke production or a decrease in combustion chamber temper-
ature, as indicated by the continuous monitoring system. If a thermal incinerator sys-
tem begins to exhibit these symptoms, the facility operator should take immediate
action to correct any operational problems. Typical thermal incinerator pressure drops
presented in Table 5 can be used as reference for checking the equipment operational
conditions.
In the case of permit review for a thermal incinerator, the data outlined below should
be supplied by the applicant. The calculations in this section will then be used to check
the applicant’s values.
Thermal incinerator system variables at standard conditions (77ºF, 1 atm) are as follows: