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316 Lawrence K. Wang et al.

where Q is the coolant flow rate (lb/h) and C is the average specific heat of
coolant p coolant
the coolant over the temperature interval T to T (Btu/lb-ºF). Specific heat data
cool,i cool,o
for coolants are available in refs. 3 and 7.
3.6. Refrigeration Capacity
A refrigeration unit is assumed to supply the coolant at the required temperature to
the condenser. For costing purposes, the required refrigeration capacity is expressed in
terms of refrigeration tons as follows:

Ref = H load 12 000 (11)
,
where Ref is the refrigeration capacity (tons).

3.7. Recovered Product
To calculate costs, the quantity of the recovered product that can be sold and/or recy-
cled to the process must be determined. Use the following equation:
Q = 60 × HAP × MW (12)
rec con HAP
where Q is the quantity of the product recovered (lb/h) and HAP is the HAP con-
rec con
densed (lb-mol), based on 1 min of operation.
4. MANAGEMENT

4.1. Permit Review and Application
In a permit evaluation, use Table 1 to check the consistency of the condensation tem-
perature (T ) and the type of coolant selected. Also, ensure that the coolant inlet
con
temperature is based on a reasonable approach temperature (a conservative value of
15ºF is used in the table). If the reported values are appropriate, proceed with the cal-
culations. The permit reviewer may then follow the calculation procedure outlined
next. Otherwise, the applicant’s design is considered unacceptable, unless supporting
documentation indicates that the design is feasible.
Compare all results from the calculations and the values supplied by the permit
applicant using Table 3. The calculated values in the table are based on the example
case. If the calculated values of T , coolant type, A , Q , Ref, and Q are
con con coolant rec
different from the reported values of these variables, the differences may be the
result of the assumptions involved in the calculations. The reviewer may then wish
to discuss the details of the proposed design with the permit applicant. If the calcu-
lated values agree with the reported values, the design and operation of the proposed
condenser system may be considered appropriate, based on the assumptions made in
this chapter.

4.2. Capital and Annual Costs of Condensers
4.2.1. Capital Costs for Condensers
The capital costs of a condenser system consist of purchased equipment costs (equip-
ment costs and auxiliary equipment) and direct and indirect installation costs. Table 4
provides factors for these costs. References 4 and 8 serve as sources for equipment costs