Baghouses
Pulse-jet cleaning cycle
Also known as pulse cycle, pulse-jet cycle, bag pulsing.
The pulse-jet cleaning cycle is the firing pattern of brief compressed-air pulses that clean the filter bags of a pulse-jet baghouse. The cycle is controlled by a sequencer (often a baghouse PLC) and is tuned through three primary variables.
Cycle parameters
| Parameter | Typical range | Effect of increasing |
|---|---|---|
| Pulse duration | 100–300 ms | More cleaning per pulse; more bag flex / wear |
| Pulse interval (continuous mode) | 10–120 s per row | Less filter cake build-up; more compressed-air use |
| ΔP set-point (on-demand mode) | 12–18 mbar | Cleaning fires only when ΔP rises; minimum bag wear |
| Pulse pressure | 4–7 bar | Stronger pulse; deeper penetration into the bag |
Continuous vs on-demand cleaning
Continuous cycling runs the cleaning sequence on a fixed schedule regardless of dust load. Simple, but wastes air and bag life on lightly-loaded periods.
On-demand cleaning fires only when differential pressure crosses a set-point. Minimises wear and air use but can fall behind when dust load spikes.
Most modern baghouses run a hybrid: on-demand control with a maximum-interval limit to prevent indefinite skipping.
How sonic horns interact with the pulse cycle
Sonic horns running continuously between pulse events keep cake from consolidating, which lets the pulse-jet system run a less aggressive cycle for the same ΔP. The combined OPEX saving (lower compressed-air use, longer bag life) is the headline argument for retrofitting horns onto an existing pulse-jet baghouse.
Related terms
Related terms
- Pulse-jet baghouseA pulse-jet baghouse cleans bags with brief, high-pressure reverse-air pulses while staying on-line. The dominant industrial fabric-filter design for new installations.
- Filter bagA filter bag is the cylindrical fabric sock that traps particulate inside a fabric filter. Media selection depends on temperature, gas chemistry, dust load and cleaning cycle.
- Filter cakeFilter cake is the dust layer that builds up on the surface of a baghouse filter bag. The cake itself does most of the fine-particle filtration; cleaning balances cake build-up against ΔP.
- Differential pressure (baghouse)Differential pressure (ΔP) across a baghouse is the pressure drop between dirty and clean plenums. It is the headline operational KPI: too low signals broken bags, too high signals fouling.
- Sonic hornA sonic horn is a pneumatically-driven low-frequency sound emitter (typically 60–400 Hz at 140–180 dB SPL) used to dislodge particulate fouling from boilers, ESPs, baghouses and process vessels.