If your air velocity is too low in your ductwork you could get dust dropping out in straight runs.  And dust collecting in ductwork is not a very good idea. 

• It is a fire / explosion hazard. If your system has a low dust loading, small enough that there isn’t enough material to support an explosion (below MEC), dust collecting in the ductwork could put the system above the MEC, thereby making the system an explosion hazard.
• Dust collecting in the ductwork causes the effective diameter of the ductwork to decrease. This causes the pressure drop through the system to increase, which will decrease the airflow through the system.  Lower airflow will cause more dust to escape the pickup hoods, thereby causing greater housekeeping, maintenance, etc.
• Dust building up in ductwork will also cause your ductwork to weigh much more. Depending on the weight the supports were designed for, if too much dust builds up, your ductwork could fall down, thereby possibly creating a dust cloud that could be explosive.

If the air velocity is too high, the static pressure of your system will be high.  This will require you to operate the exhaust fan at a higher speed.  This could increase the noise, power used and wear and tear.  High air velocity could also increase the erosion of the ductwork, thereby developing holes in the ductwork which will leak air into the system and decrease the actual airflow at the pickup points.

Watch for our upcoming article on sizing of ductwork for your dust collection system.

Baghouses and cartridge collectors often use compressed air / plant air to clean the filters.  By pushing compressed air through the filter, in theory, dust should be removed from the filters.  However,  air compressors are high maintenance pieces of equipment that have high operating costs.  Also, the filters are never completely dust free after an air blast, meaning that, over time they become blinded. This high time-and-monetary cost can be lowered by breaking away from using compressed air and instead using a cyclone pre-filter in your dust collection system.

 By putting a cyclone pre-filter ahead of your filters you can:

• Decrease the loading on filters, reducing their cleaning from twice a minute to possibly once every 2-3 minutes.
• Eliminate the wear and tear on your filters and therefore the risk of your filter developing a hole and compromising the whole filter.

If you are looking to save money on your compressed air usage, a pulse-on-demand controller with a cyclone pre-filter is a good option to explore.

Contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com to help you problem-solve your dust collection problems.

Hoods are probably most important component in a dust collection system because they will:

1. direct the dust away from the employees and equipment, even if the dust collector is not operating correctly
2. allow dust to be captured at the lowest airflow possible, saving you money

If a hood is improperly designed it will not capture the dust from an application, no matter how well your dust collector or fan is designed.

A few things to remember on hood design:

• Place the hood as close to the dust generating area / equipment as feasibly possible to lower the airflow required
• Use the Industrial Ventilation Handbook to help you design / evaluate your hood
  1. Location
  2. Geometry
  3. Pickup velocity
• If you use of local dampers for greater flexibility in the future remember they could allow un-intentional changes

Click here to get an easy how-to-guide for selecting the right dust collector for your specific application.

If you have questions about your hood design or your dust collection systems our consultants are here to help.

Contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com to help you problem solve your dust collection problems.

Variable Frequency Drives allows for you to control the airflow through your system by changing the fan speed without breaking the bank.  Without VFDs, one has to manually open or close dampers, creating high manual labor cost. Furthermore, if there are multiple dampers on the system, then tampering with the opening and closing of any one damper, can cause the airflow balance to be off and can increase the static pressure of the system.  

The VFD allows you to control the airflow of the fan, rather than allowing a constant high air output, as would be the case when dampers are being used. VFDs give the system the airflow that is required while lowering electrical costs.  VFDs can further lower costs by replacing motor starter control panels. All in all, using a VFD is the smart way to control your airflow.

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

Dampers are used in dust collection systems to control the airflow to specific branches of the ductwork.  This is done by opening or closing the damper.  Air, like water, travels the path of least resistance.  By using a damper, you are changing the resistance to the air.  Every dust collection system should have a manual damper near each hood/pickup point to balance the system.  This makes sure that the system is properly operating.  An unbalanced system could cause too much air to be pulled from one area (causing loss of product) while in another area not enough airflow is available to capture dust.  Other times, a soft connect (space between flanges) is used to control airflow at a pickup point.  However, this isn’t very efficient.  This keeps the airflow in that area constant, but it’s picking up air from an area where it isn’t required.  A damper would work much better, since you are only moving the air in the area you need.  Soft connects are only advantageous when you are looking to cool down an airflow using outside air.  Dampers can also be used to shut off portions of the system that are not being used, thereby allowing a smaller system.

So when you are looking at your dust collector system, don’t forget dampers.  They allow you to optimize your system.

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

Dust collection systems consist of four major items.  All of them are important and can cause a dust collection system to underperform.  The major items are the exhaust fan, dust collector, ductwork, and hoods/pickup points.   While the exhaust fan provides the motive power to collect the dusty air, its performance is affected by each of the components.  This means that if one of the other components isn’t operating as designed, the whole system will be affected.  Ductwork is usually by far the largest component and often the most overlooked.  Depending on the size of your system, the ductwork can span hundreds of feet and have dozens of side streams.  The ductwork is like railroad tracks, it moves the dusty air from one place to another.

Often times, additional lines will be added to a dust collector system after installation.  Without proper evaluation of the system, this could negatively affect the performance of the whole system.  This means that just because the dust collector system was operating correctly before, it might not after an additional pickup point or hood is added.  What happens is that when you add additional pickup points, you change the balancing of the system.  This could change the airflow to each and every hood and pickup point in the system, so while the system was originally adequately venting an area, it might not after a change.

A few things can be done to address this, such as changing fan speed, adding dampers, modifying ductwork, etc.  The main thing you need to keep in mind is that if you slow the airflow through ductwork too much, you begin to build up dust within the line.  This will further restrict your airflow and become a fire / explosion hazard.

So when you are looking at changing your dust collector system, review the system parameters or hire someone to review so that you do not cause additional issues.

Learn about the questions you should be asking to make sure you're buying the right dust collector for your application. Get your whitepaper now.

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

Now in its third year, Ceramics Expo is the world's largest annual free-to-attend expo for the advanced ceramic and glass community.

The massively expanded event stands as a unique showcase for all the latest start materials, industrial equipment, technical ceramic components, processing expertise, analysis and testing devices, thermal technologies and precision finishing systems that keep this sector at the forefront of manufacturing advances.

Due to its tightly focused approach and by maintaining a close relationship with all core stakeholders, Ceramics Expo guarantees the participation of respected and innovative suppliers. As the premier US ceramics exhibition, it draws in thousands of genuine decision makers and aims to set the agenda for ceramics manufacturing and applications.

Aerodyne Environmental's industrial dust collection products feature unique, low-maintenance designs that will enhance the performance of your processing operations. Our industrial dust collectors, which work horizontally or verticaly, can extend the life of your baghouse or cartridge filters. And, Aerodyne offers a variety of durable material handling valves for every application, including the Vacu-Valve Trickle Valve System, a cost-effective solution to rotary valves.

If you are working with a high value material or product, then you should investigate using a cyclone ahead of your baghouse or cartridge collector.  The cyclone will allow you to recover the dust without contamination from the filters.  The filters in a baghouse or cartridge collector use a dust layer built up on the filters to collect the dust from the airstream.  During the process of filter cleaning, dust from this layer is dislodged and falls into the hopper.  Any particulate from prior batches can cause contamination of the dust.

A cyclone, on the other hand, collects the dust and deposits it in the hopper continuously.  There is very little dust buildup inside of a cyclone.  This minimizes the chances of contamination from prior batches.  Since there aren’t any filters, a cyclone can be washed or wiped out to remove the prior batch particles.

One area where this could be very helpful is pigment collection.  A baghouse or cartridge collector filter will collect the pigment and contaminate the color.  This requires the filters to be changed every time a new color is produced.  So the system will require a filter set for every different color produced.  Conversely, the cyclone can be washed out or wiped down between colors.  This saves in both maintenance time and spare parts costs.

With the release of NFPA 652 and 654, manufacturers that create dust in their processes are required to conduct a Dust Hazard Analysis if the dust is explosive.  NFPA 652 requires this to be done by 9/7/2018 but NFPA 654 has extended it 5 years.  The Dust Hazard Analysis is retroactive, so all manufacturers are required, no one is grandfathered in.

The DHA should be as simple or as complex as the process and needs to be documented for OSHA.  The main purpose of the DHA is to educate the owner and operators on the true hazards and dangers they are facing with their dust, and to make sure they take the proper precautions with it.  The DHA is there as a tool to prevent loss of life, equipment, production time, and capital.

Aerodyne will be addressing the DHA further in future Blogs!  Stay tuned.

When you are specifying your dust collector, don’t just settle on a rotary valve.  There are other airlocks that might be better suited for your application.  Other airlocks include the double dump (flap) valve, trickle valve, and knife gate.  Not to mention just bypassing an airlock totally and connecting a hopper directly to the bottom of the dust collector.

The following will help you figure out which is the best solution:

1. Rotary valve – Use this if you have combustible dust. However, you will have constant air leakage across the valve.
2. Double dump valve – Use this if you want to minimize air leakage. The Double Dump works great with big, chunky material or if you’re worried the material may wrap around a rotary valve rotor.
3. Trickle valve – Use to save money and time. Requires a vacuum and usually a fine, free-flowing particle to work effectively.  It’s low cost and easy maintenance makes it very attractive when suitable.
4. Knife Gates – Used for periodic emptying of the dust collector hopper into another container. Knife gates come in a variety of design (knife gate, slide gate, orifice type, etc.).  Depending on the design, they can provide an airtight seal or not.  However when open, the airlock is lost.
5. Direct couple to a hopper – Used with low dust loading and could require the dust collector to be turned off during changing of the hopper. Also be-careful to take into account the lower hopper when used on a combustible dust application.

When you are looking for an airlock, don’t just automatically use a rotary valve.  Doing so may cause operational and maintenance issues in the future.  It could also cost you more money.  If you would like help in picking the best airlock, don’t hesitate to contact Aerodyne at 440-543-7400 or dc@dustcollectorhq.com. He is available to help you to solve your dust collection issues.