Baghouse Differential Pressure Calculator

Determine tube sheet differential pressure drop (ΔP in inches w.g.), clean fabric vs dust cake resistance breakdown, and exhaust fan electrical energy costs.

Filter Cloth Area (sq ft)

Exhaust Airflow (ACFM)

Filter Media Type

Dust Cake Loading (W)

lb/sq ft

Dust Cake Resistance (K2)

Annual Operating Hours

Total Tubesheet Differential Pressure

5.60" w.g.

Optimal Operating Window (4.0" - 6.0" w.g.)

Dust Cake Resistance

3.60" w.g.

64.3% of total loss

Clean Media Resistance

2.00" w.g.

Fabric base drop

Filtration Velocity (A/C): 4.00 ft/min

Exhaust Fan Power Draw: 26.5 BHP (19.8 kW)

Annual Fan Electrical Cost: $9,790 / yr (@ $0.11/kWh)

Differential pressure is balanced, ensuring high filtration efficiency while protecting fan energy costs.

Recommended Tools & Equipment

Tested hardware and components for high reliability

100% Free Tool Zero Sign-Up

Baghouse Differential Pressure & Filtration Resistance

Differential pressure (ΔP) across a baghouse tubesheet is the sum of the aerodynamic drag across the clean filter media fabric plus the resistance of the accumulated porous dust cake layer. In fabric filtration, the dust cake actually performs the majority of fine particulate capture (surface sieving).

Empirical Drag & Resistance Formulations

Darcy's Law for Fabric Filtration:
ΔP_total = ΔP_fabric + ΔP_cake = (K_1 × V) + (K_2 × V × W)
Where V is filtration face velocity (A/C ratio), K_1 is clean fabric drag coefficient, K_2 is specific dust cake resistance, and W is dust cake areal density (lb/sq ft).
Fan Power Energy Penalty:
Fan BHP = [ ACFM × ΔP (inches w.g.) ] / [ 6,356 × Fan Efficiency (≈0.70) ]

Frequently Asked Questions

What is a normal operating differential pressure for a baghouse?

A healthy pulse-jet baghouse typically operates between 3.5" and 6.0" inches of water gauge (w.g.) across the tubesheet. Consistently running above 7" to 8" indicates blinded bags.

Why is some dust cake necessary for effective baghouse filtration?

The clean woven or felted fibers have pores larger than fine sub-micron dust. The initial dust cake layer (the primary porous matrix) performs over 99% of fine particulate filtration.

How much energy does an extra 2 inches of baghouse pressure drop consume?

In a 50,000 CFM system, every 2" w.g. of unnecessary differential pressure adds approximately 22.5 brake horsepower to the exhaust fan motor, costing over $8,000 per year in electricity.