Page 105 - Air Pollution Control Engineering

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Fabric Filtration 85

5. The material handling system to remove the solids must be able to handle a maximum of
 8000 ft  .  1b   60 min  1b
0 8 grains 
3
    = 55
 min  ft 3   7000 grains  h  h
This assumes 100% filter efficiency (1320 lb/d for 24-h operation).

Example 5
What is the “HAP Emission Stream Data Form” recommended by the US Environmental
Protection Agency (US EPA)?

Solution
The “HAP Emission Stream Data Form” recommended by the US EPA is presented in
Appendix 1.

Example 6
Prepare a step-by-step calculation procedure for design of a fabric filtration system.

Solution
1. Engineering data gathering for the HAP emission stream characteristics:
1) Flow rate: Q = acfm
e,a
2) Moisture content: M = % (vol)
e
3) Temperature: T = °F
e
4) Particle mean diameter: D = µm
p
5) SO content = ppm (vol)
3
6) Particulate content = grains/scf
7) HAP content = % (mass)
2. Determine or decide the following engineering data for permit review and application:
1) Filter fabric material
2) Cleaning method (mechanical shaking, reverse air, pulse jet)
3) Air-to-cloth ratio ft/min
4) Baghouse construction configuration (open pressure, closed pressure, closed suc-
tion)
5) System pressure drop range in. H O
2
3. Pretreatment Considerations:
If the emission stream temperature is not from 50°F to 100°F above the dew point,
pretreatment is necessary (see Chapter 1). Pretreatment will cause two of the pertinent
emission stream characteristics to change; list the new values below.
1) Maximum flow rate at actual conditions: Q = acfm
e,a
2) Temperature: T = °F
e
4. Fabric Filter System Design
1) Fabric type(s) (use Table 3)
a.
b.
c.
2) Cleaning method(s)
a.