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Catalytic Oxidation 385

history of the catalyst, and the design of the unit. Given that these parameters are so vari-
able, it is not possible to accurately predict the catalyst replacement costs for a given
application. For purposes of this handbook, it is assumed that the catalyst has a life-span
of 2 yr. Based on this assumption, the catalyst replacement cost can be determined by
multiplying the catalyst volume determined in Section 4.2 by the appropriate capital
recovery factor (assuming a 2-yr life and 10% interest rate [i.e., CRF = 0.5762]) and the
unit cost of catalyst replacement. The catalyst replacement cost can be estimated as
3
$650/ft for base metal oxide catalysts and $3000 for noble metal catalysts in 1990 (6).
The capital cost of a catalytic incinerator is estimated as the sum of the equipment
cost (EC) and the installation cost. The equipment cost is primarily a function of the
total emission stream flow rate and the heat-exchanger efficiency as well as the cost of
auxiliary equipment.
After obtaining equipment costs, the next step in the cost calculation is to obtain the
purchased equipment cost (PEC). The PEC is calculated as the sum of EC (incinerator and
auxiliary equipment) and the cost of instrumentation, freight, and taxes. Appropriate fac-
tors can be applied to estimate these costs. After obtaining the PEC, the total capital cost
(TCC) is estimated using the factors presented elsewhere (6).
Operating labor requirements are estimated as 0.5 h per 8-h shift. The operator labor
wage rate is provided elsewhere (6). Supervisory cost is typically estimated as 15% of
operator labor costs.
Maintenance labor requirements are estimated as 0.5 h per 8-h shift with a slightly
higher labor rate to reflect 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 esti-
mated 10-yr equipment life and subtracts out the initial catalyst cost, whereas overhead,
property taxes, insurance, and administrative costs are percentages of the total capital cost.
5.3. Decision for Rebuilding, Purchasing New or Used Incinerators
Examples on how to make decisions on rebuilding, purchasing new incinerators or
purchasing used incinerators have been presented by Gallo et al. (15), Moretti and
Mukhopadhyay (16), Cooley (17), and Arrest and Satterfield (18). Many catalytic oxi-
dizers are commercially available (19–21). Assistance can be a obtained from the US
EPA (23, 24).

5.4. Environmental Liabilities and Risk-Based Corrective Action
Traditional approaches to environmental cleanups have been challenged by rising
remediation and treatment costs, stricter regulatory compliance requirements, greater
demands for protection of the public and the environment, and, of course, mounting
business concerns, such as future legal and financial liabilities. Certain stakeholders seek
“absolute” clean or zero concentrations of foreign chemicals in the environment. The goal
of “clean” has become increasingly more elusive, as newer, improved instrumentation and
analytical methods continually lower the detection limits.
Not only do the investigation and cleanup costs dramatically increase while the plant
managers are chasing this ever diminishing target “clean” concentration, but the liability