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78 Lawrence K. Wang et al.

Table 8
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Bag Prices (3rd quarter 1986 $/ft )
Type of material a
Bag diameter
Type of cleaning (in.) PE PP NO HA FG CO TF

1
Pulse jet, TR b 4 ⁄2 –5 ⁄8 0.59 0.61 1.88 0.92 1.29 NA c 9.05
1
6–8 0.43 0.44 1.56 0.71 1.08 NA 6.80
1
Pulse jet, BBR 4 ⁄2–5 ⁄8 0.37 0.40 1.37 0.66 1.24 NA 8.78
1
6–8 0.32 0.33 1.18 0.58 0.95 NA 6.71
Shaker
Strap top 5 0.45 0.48 1.28 0.75 NA 0.44 NA
Loop top 5 0.43 0.45 1.17 0.66 NA 0.39 NA
Reverse air with rings 8 0.46 NA 1.72 NA 0.99 NA NA
Reverse air 8 0.32 NA 1.20 NA 0.69 NA NA
w/o rings d 11 ⁄2 0.32 NA 1.16 NA 0.53 NA NA
1
Note: For pulse-jet baghouses, all bags are felts except for the fiberglass, which is woven. For bottom
access pulse jets, the cage price for one cage can be calculated from the single-bag fabric area
using the following:
In 50 cage lots: $ = 4.941 + 0.163 ft 2 $ = 23.335 + 0.280 ft 2
In 100 cage lots: $ = 4.441 + 0.163 ft 2 $ = 21.791 + 0.263 ft 2
In 500 cage lots: $ = 3.941 + 0.163 ft 2 $ = 20.564 + 0.248 ft 2
a PE = 16-oz polyester; PP = 16-oz polypropylene; NO = 14-oz nomex; HA = 16-oz homopolymer
acrylic; FG = 16-oz fiberglass with 10% TeflonTM; CO = 9-oz cotton; TF = 22-oz TeflonTM felt.
b Bag removal methods: TR = top bag removal (snap in); BBR = bottom bag removal
c NA = Not applicable
d Identified as reverse-air bags, but used in low-pressure pulse applications.
5
These costs apply to 4 ⁄2-in.- or 5 ⁄8-in.-diameter, 8-ft and 10-ft cages made of 11 gage mild steel and hav-
1
ing 10 vertical wires and “Roll Band” tops. For flanged tops, add $1 per cage. If flow-control Venturis are
used (as they are in about half of the pulse-jet manufacturers’ designs), add $5 per cage.
For shakers and reverse air baghouses, all bags are woven. All prices are for finished bags and prices can
vary from one supplier to another. For Gore-Tex TM bag prices, multiply base fabric price by factors of 3–4.5.
Source: ref. 8.

bags, and compressed air), operating labor, and maintenance costs. Indirect costs con-
sist of overhead, administrative costs, property taxes, insurance, and capital recovery.
Table 10 provides the appropriate factors to estimate these costs.
The bag replacement labor cost depends on such factors as the number, size, and type
of bags, the accessibility of the bags, how much they are connected to the tube sheet,
and so forth. As such, these costs are highly variable. For simplicity, assume a conser-
2
vatively high cost of $0.14/ft net bag area, per EPA guidance (8). Dust disposal typi-
cally comprises a large cost component and varies widely with site. The reader should
obtain accurate, localized costs. These fall between $20/ton and $30/ton for nonhaz-
ardous waste, and 10 times this amount for hazardous material (8).
The cost of operating labor assumes a requirement of 3 h per 8 h shift and the wage
rate is provided in Table 10. Supervisory costs are taken as 15 % of operator labor costs.
The cost of maintenance assumes a labor requirement of 1 h per 8 h shift, and the wage