When you have a combustible dust, not only does your dust collector require to be protected against a deflagration, but the airlock must contain the event.  NFPA-69 allows the use of a rotary valve as long as the following:

1. Deflagration isolation by flame quenching (close-clearance valves) or
2. Deflagration isolation by material blocking (product layer above the valve)

Most rotary valves use flame quenching to achieve compliance with the spec.  Basically this requires the valve to have a clearance to the housing no greater than 0.2 mm and have at least six vanes, so that two vanes are isolating the event at all times.

Many rotary valves manufacturers comply with these specifications.  When you are looking at a rotary valve for you combustible dust application, remember to confirm that the valve complies with NFPA-69. 

If you are having operational issues on your dust collection system, contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com.  He is available to help you problem solve your dust collection issues.

A dust collection system is much more than just the dust collector (ex. Cyclone, baghouse, cartridge collector, wet scrubber, etc.).  It constitutes the exhaust fan, hoods, instrumentation and interconnecting ductwork.  If any of these components are improperly sized or operating, the whole system can fail in its primary objective, dust collection.

Today we are discussing the differential pressure gage.  The differential pressure gage is an often overlooked piece of equipment on dust collectors, especially cyclones.  By measuring the differential pressure across your dust collector, you are monitoring your system performance.  If the differential pressure gage suddenly changes, it is telling you something has recently changed in your system.  If you see a gradual change in the differential pressure, then it is telling you that the system is gradually changing.

A sudden change is telling you that the airflow has suddenly increased or decreased.  This could be caused by a variety of reason (plugging of filters, opening of damper, closing of damper, etc.)  When you see this happen, your removal efficiency will be affected.  So it’s better to start identifying the issue before you are forced to.

A gradual change is telling you that the ductwork or filters are starting to plug up.  This could be normal operating conditions or caused by a change in process.  When you notice a gradual change in the pressure drop, schedule a maintenance inspection before it gets too drastic.  That way you won’t be forced shut down in an emergency.

If you are having operational issues on your dust collection system, contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com.

A dust collection system is much more than just the dust collector (ex. Cyclone, baghouse, cartridge collector, wet scrubber, etc.).  It constitutes the exhaust fan, hoods, instrumentation and interconnecting ductwork.  If any of these components are improperly sized or operating, the whole system can fail in its primary objective, dust collection.

Today we are discussing the exhaust fan.  The exhaust fan could be the most important component in the dust collection system.  It provides the motive force for the whole system.  If it isn’t performing as required, the system will fail.  The proper fan impeller (wheel) must be used if the fan is to operate correctly.

There are three types of wheels/impellers:

• Radial wheel (Ex. open material handling and material handling) - These wheels should be used when the fan is on the dirty side of a dust collector or after a dust collector where a large amount of dust remains in the airstream (ex. after drop out box). The wheel is designed so it can handle dust in the air.  The open type wheel is used when there is a high dust loading and/or the dust is fibrous.  Its design helps prevent the dust from wrapping around the wheel.

• Air handling wheel – The air handling wheel is designed for clean airstreams or extremely light dust loading. These wheels should always be used on the clean side of and dust collector and never on the dirty side.  They are usually more efficient in air movement than the radial wheels.

• Axial wheel – These wheels are usually never used on dust collection systems. They will move a lot of air, but without much force behind them.  If possible, stay away from axial fans on your dust collector system.

If you are having issues with the fan on your dust collector, check the wheel.  Make sure you are using the proper type.    

Find out more at Dust Efficiency Clinic.

If you are having operational issues on your dust collection system, contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com.

Aerodyne Environmental, the industry’s leading manufacturer of industrial cyclonic dust collectors and dust collection valves, recently assisted in a pharmaceutical application. A prominent US pharmaceutical company was creating a dust collection system for the facility where a variety of drugs are manufactured. The company plans on using a cartridge collector as part of the tablet manufacturing process. Because this company is regulated by the FDA, every gram of product must be accounted for, even the dust. The active pharmaceutical ingredients (APIs) that are created are extremely fine and flow like water. The cartridge collector would be able to collect the particulate in the process, but much of it would get stuck in the filters and would be hard to account for. Read more about this case study.

Do you need to provide product reconciliation or are you spending too much time gathering the product from your dust collector?

The “EZBIBO” system was originally designed for use with Aerodyne GPC Cyclones to allow for easier bag-in bag-out capture systems for low toxic level pharmaceutical dusts typically encountered with encapsulators, pill coating systems, and some mixing operations.  The system allows for capture and bagging of waste material in the pharmaceutical process allowing for weighing and accounting of all materials used in a process, with minimal exposure to operation personnel.

With government regulations tightening on solid emissions, baghouses and cartridge collectors have become status quo in the past 40 years.  The fabric filters (bags or cartridges) remove dust below 1 micron in size.  The high removal efficiency of the filters, have been considered best available removal technology.  This means most processes requiring dust collectors will use a baghouse or cartridge collector.  However, not all processes work well with baghouses and dust collectors.

The pharmaceutical industry has unique requirements that normal industrial applications do not have.  Whether it’s the strict FDA rules or the flexibility of batch production, normal industrial practices and equipment don’t always apply.  Even with continuous production becoming more popular, pharmaceutical applications are different than standard industrial applications.

The Vacu-Valve is a low cost alternative to a rotary valve.  There are no motors, pneumatics, or moving parts as it operates by using the system vacuum above to seal the sleeve.  This is typically from a cyclone, baghouse, or cartridge collector.  Since the sleeve is split, gravity will slowly pull the solids down through the sleeve until they exit the sleeve and fall into the collection hopper.  As you can see from the description, not all solids will easily pass through this.  The ideal particulate would be sand.  It’s small, spherical shape and the density allows it to easily pass through the valve.  It doesn’t bridge easily.

How does the OSHA silica rule affect me?