Page 273 - Air Pollution Control Engineering

05_chap_wang.qxd 05/05/2004 3:50 pm Page 252
252 Lawrence K. Wang et al.

2. The cost of scrubbing liquor (most likely water) is given by

WR = 0.6(Q ) HRS (31)
e,a
where WR is the water consumption (gal/yr).
The annual water cost, which equals ASC in Eq. (27), is obtained from the multi-
plication of the yearly water requirement and the unit water cost, which equals
USC in Eq (27) found in Table 17. The USC cost water is assumed to equal $0.20
per 1,000 gal:
ASC = (USC)(ASR) (27)
ASC = ($0.20/1000 gal)(ASR)
ASC = $
3. The annual operating labor costs are estimated by assuming that for every 8-h shift the
Venturi scrubbing system is operated, 2 h are required to operator the wet scrubber.
With labor cost at $12.96/h (see Table 7),

Annual operating labor hours = (2.0 h/shift) (no. shifts/day) (no. days/wk) (no.
wk/yr)
Annual operating labor hours = HRS = h
Annual operating labor cost = ($12.96 / h) HRS = $
The supervisor labor cost is estimated at 15% of operating labor cost (see Table 7).
Annual supervisor labor cost = (0.15)(annual operating labor cost)
Annual supervisor labor cost = $
4. The annual maintenance labor cost is estimated by assuming that for every 8-h shift
the scrubbing system is operated 1.0 h is required to maintain the wet scrubber. The
maintenance labor cost is based on the rate of $14.96 per hour (see Table 17). This
cost is determined as follows:

Annual maintenance labor hours = (1.0 h/shift) (no. shifts/day)(no. days/wk)
(no. wk/yr)
Annual maintenance labor hours = HRS = h/yr
Annual maintenance cost = ($14.26 / h) HRS = $
5. The annual maintenance materials cost is estimated by assuming that it is equiva-
lent to 100% maintenance labor cost. This cost is determined as follows:
Annual maintenance materials cost = (100 %)(annual maintenance labor cost)
Annual maintenance materials cost = (1.0)(annual maintenance labor cost) =
$
C. Indirect Annual Costs—Venturi Scrubber
Table 17 lists indirect cost factors. These factors and value for TCC are utilized to
determine indirect annual costs (ICA) as follows:
Overhead = 0.60(annual operating labor & maintenance costs)
Overhead = $
Property Tax = 0.01(TCC)
Property Tax = $
Insurance = 0.01(TCC)
Insurance = $