Question

A pulse-jet bag filtration unit is being proposed to be installed to clean an air stream containing particulate pollutants. Design and operating data as well as the fabric information are given below.

Volumetric flow rate of the polluted air stream = 10,000 cfm (at 60oF, 1 atm)Operating temperature = 250oF
Operating pressure = 1 atm
Concentration of pollutants = 4 gr/ft3

Gas-to-cloth ratio (G/C) = 2.5 cfm/ft2 cloth (at operating condition) (G/C = gas volumetric flow rate per unit area of filter cloth) Collection efficiency = at least 99%

Select the most appropriate filter bag fabric by considering both process compatibility and cost. Show your analysis that justifies your choice of filter. How many the selected bags are required to meet at least 99% collection efficiency? How much the selected bags will cost?

Filter bag	A	B	C
Maximum temperature (oF)	260	275	220
Cost per bag ($)	26	38	20
Standard size of bag (bag diameter × length)	8 in × 16 ft	10 in × 16 ft	1 ft × 16 ft

Answer 1