Recently the plant's baghouse has not been effective in evacuating the dust at the pickup points. It doesn't seem as if there is enough air movement through our shaker-style unit. What should we do?
While baghouses are relatively easy to maintain and operate, a smooth operating unit will have good air flow. High pressure drop (the difference in air pressure from the clean air intake and air exhaust) indicates that air flow is restricted. This situation may be caused by one or more of five conditions. Here's a quick checklist: Is the collection hopper free of buildup? Wet material caked up on the hopper sides or discharge chute restricts air flow through the exhaust. Also, clear the notary airlock, cleanout auger, and the collection hopper if necessary. Check the differential pressure gauge. Plugged pressure taps, leaky hoses, or a malfunctioning diaphragm in the gauge create false pressure readings. Check these items at least annually. Check the operating adjustments of the bag-cleaning mechanism. Increasing the cleaning frequency will reduce dust buildup on the bags. Wet spring weather will require different frequency and duration settings than those in a dry summer. Check the age and condition of bags. Older bags might need dry-cleaning or replacement. Aging cloth loses its texture and flexibility. Over time the shaking can cause the bag fabric's weave to open up, allowing dust particles to fill in the openings. Is the dust falling away from the bag? Even with new or recently cleaned bags, factors can reduce a bag's surface texture and even cause the dust to stick. Be certain that the bag type is designed for the type of dust it is collecting. Most shaker-type units use bags with a polyester sateen finish that is smoother than bags used on a jet-pulse collector. Finally, call the baghouse manufacturer. Their lab can analyze a sample of the dust and the bag to determine dust-bag compatibility and blinding potential.