NOx Emissions from Cement Mfg - US Environmental Protection ...

to power control instrumentation and auxiliary equipment and the
energy requirements for vaporization and injection of ammonia for
SCR systems. The cost for electricity and compressed air is
considered to be negligible relative to the other operating
costs.
6.1.3.2 Operating and Supervising Labor. There are no
postcombustion NOx control technologies currently being used in
the United States. Therefore, information for typical operating
labor requirements from the cement industry was unavailable. A
requirement of 1 hour of operator attention was assigned for an
8-hour shift, for all postcombustion technologies considered,
regardless of the plant size. For in-combustion techniques such
as low NOx burner, additional operator assistance required solely
for NOx control purposes was assumed to be negligible. Operator
wage rates were estimated to be $28.22/hr in 1992, based on
escalating the costs presented in Reference 4 by 5 percent per
year to account for inflation. Supervisory labor costs were
estimated to be 15 percent of the operating labor costs
consistent with the OAQPS Control Cost Manual.
6.1.3.3. Maintenance. Specific maintenance costs were not
available from the control system vendors and manufacturers. The
guidelines for maintenance costs in Reference 2 suggest a
maintenance labor cost of 0.5 hours per 8-hour shift and a
maintenance material cost equal to this labor cost.
Alternatively, a maintenance cost of 10 percent of the PEC is
used to prevent excessive maintenance costs relative to the PEC.
6.1.3.4 Overhead. An annual overhead charge of 60 percent
of the total maintenance cost was used, consistent with
guidelines in Reference 2.
6.1.3.5 Property Taxes. The property taxes were calculated
as 1 percent of the total capital cost of the control system, as
suggested in Reference 2.
6.1.3.6 Insurance. The cost of insurance was calculated as
1 percent of the total capital cost of the control system, as
suggested in Reference 2.
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