When selecting the best cyclone for your process, there are many different factors that affect the sizing and cost of the cyclone.  The cyclone must be sized so that it handles the airflow of the system and components.  The proper design for the required removal efficiency must be used.  The process will also dictate the materials of construction and special requirements.  The location where the cyclone will be installed will influence the cyclone orientation.  Cyclones aren’t a stand-alone piece of equipment; support equipment is required for proper operation.  Therefore, the scope of supply will affect the cyclone costs and design.  The following is a brief description of the different elements that affect cyclone sizing and pricing.

Part 1: Airflow and Pressure Drop

The most basic (and important) thing that affects the sizing of a cyclone is the airflow the cyclone will see.  Cyclones are a mechanical separator without any moving parts.  They are designed in such a way that the more air you put through the cyclone the greater the pressure drop the air will experience going through the cyclone.  To understand this better, a quick review of how a cyclone works will be beneficial. 

Air enters a cyclone near the top of the cyclone.  The inlet is designed so the air will rotate around the walls of the cyclone heading down towards the hopper.  This creates centrifugal forces which send the heavier, larger particles out towards the walls.  Once the air gets down to the hopper, the air goes through a process called vortex reversal.  This means the air turns 180° and goes up through the middle of the cyclone.  The air outlet is located on top of the cyclone.  Often times, the air inlet of the cyclone is located on the tangential, while the cyclone outlet pipe helps form the centrifugal motion.

The greater the airflow through a cyclone the higher the pressure drop the cyclone will have.  So a cyclone will have different pressure drops for different airflows through it.  The pressure drop is not dependent on material loading or cleaning cycles.  The chart shows the pressure drop an Aerodyne GPC-24 will have at a variety of airflows.

 

When picking a cyclone for your application, you will have to figure out what pressure drop you want through the cyclone.  With a lower pressure, you will have a smaller fan and larger cyclone.  Smaller fans will have lower initial and operational costs while larger cyclones have greater initial costs.

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5 Signs Your Dust Collection System Needs a Pre-Filter

Watch the video from the Dust Efficiency Clinic discusses how using a pre-filter will optimize your dust collection system. 

 

If you prefer this valuable information in white paper form, get our whitepaper, Top 5 Reasons to Use a Cyclone as a Pre-filter.

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

When sizing a cyclone dust collector, there are many factors that have to be reviewed in order to pick the best model for your applications. Some of them are:

Airflow

What is the airflow going through the cyclone?  The cyclone size is directly tied to the amount of air going through it. The more air there is, the larger the cyclone required.  Without a doubt, this is the most important requirement for sizing a cyclone.

Temperature & pressure

The airflow volume is based on the temperature and pressure by the ideal gas law.  The cyclone need to be sized based on ACFM (actual).  Often times, customers provide SCFM (standard), which is the airflow when the temperature and pressure is 70°F and 1 atmosphere.  If SCFM is provided, then it needs to be converted to ACFM for the correct cyclone to be selected.  If not, the cyclone might be undersized, thereby increasing the pressure drop in the cyclone significantly, which can cause airflow issues.

Dust

The actual dust being collected also affects the cyclone selection.  Is the dust explosive?  What removal efficiency do you require?  What is the dust’s physical characteristics, such as does it bridge, is it sticky, is it abrasive?  All-of-these can affect the design of the cyclone.  Example, a dust that bridges might have a special hopper to help prevent bridging.

Location

The location where the cyclone will be installed has a great influence on the cyclone selection.  Is it located indoors or outdoors?  How much space is available?  Is there a height restriction? Will a vertical cyclone fit or must a horizontal cyclone be used.  Is the cyclone being used as a pre-filter or is it the final dust collection equipment? 

Fan

If this isn’t a new application, the static pressure the fan has available is extremely important.  The fan must have enough static pressure to overcome the pressure drop of the cyclone without decreasing the airflow through the system.  This may require modifying the fan, replacing the fan or installing a larger cyclone.

Material of Construction

The cyclone must be constructed of the proper materials so it doesn’t rust or react with the material going through it.  Often times the MOC will be carbon steel or a stainless steel.  Special material of construction might be used, or a coating is applied (either internal or external) to extend the cyclone’s life.

Special considerations

There are additional things that may need to be considered when selecting the cyclone.   Some examples include does it need to be cleaned often, so quick access is required?  Are special welds, material finishing, etc. required?

These are some of the main considerations that are taken into account when a cyclone is sized for a dust collection system.

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The GPC Dust Collector is an efficient way to handle your dust collecting needs.

Simply click the button below to find out more about the advantages and the specifications of the Aerodyne GPC Dust Collector.

 

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

A cyclone pre-filter offers multiple benefits to your dust collection system. One of these benefits and easiest to observe is extending filter life.

How Do Cyclone Dust Collectors work?

Cyclone dust collectors remove dust by using centrifugal motion.  The airflow enters the cyclone and spins around until it reverses and leaves the cyclone through the center of the vessel.  As the airflow spins, centrifugal motion pulls the dust towards the wall, leaving cleaner air in towards the center of the vessel.  So when the airflow reverses, the dust falls into the hopper while the clean air leaves through the center of the cyclone.

The larger and heavier a dust particle is, the greater the centrifugal force on it and the more likely it is to move towards the walls.  What this basically means is that the larger the particles the greater the removal of those particles in a cyclone.

A cyclone pre-filter will remove the larger particles from an airstream.  Often times this can be as much as 80-90% of the dust loading in the airflow.  Installing a cyclone pre-filter could decrease the loading on the filters by 80-90%, which in turn will allow a longer time between cleaning of the filters.

“Pulse-Jet” Baghouse   

In a “pulse-jet” baghouse the filters are cleaned by blasting compressed air through them.  This causes the filters to expand off their support.  The expansion causes the top layer(s) of dust to fall off the filters, thereby cleaning them.  Now each time the filter expands, the filter is weakened.  Over time, holes will develop in the filter, thereby allowing unfiltered air past.  This lowers the removal efficiency and could cause the system to be out of compliance.

Dust Built-Up Over Time

Another issue is over time, the top dust layers might not fully fall off.  So the total dust on the filters increases, making it harder for air to pass through.  This causes the pressure drop across the filters to increase, which will result in less air being collected at the collection points.

Installing the cyclone pre-filters decreases the dust getting to the filters, thereby requiring less cleaning (weakening of the filters) and lowering the amount of dust that builds up on the filters.  Together this can extend filter life by many months to a few years, which will lower your maintenance costs.

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5 Signs Your Dust Collection System Needs a Pre-Filter

Watch the video from the Dust Efficiency Clinic discusses how using a pre-filter will optimize your dust collection system. 

 

If you prefer this valuable information in white paper form, get our whitepaper, Top 5 Reasons to Use a Cyclone as a Pre-filter.

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

A significant benefit of using a cyclonic dust collector as a pre-filter for baghouses or cartridge collectors is increasing removal efficiency. A cyclone removes all types and particle sizes of dust. At larger particle size, dust collection is nearly 100% but with smaller size (ex. sub-micron) particulate the collection can typically less than 5%.

Filter Cleaning Cycle

Filters such as bags and cartridge collectors get their high removal efficiencies by building up a dust layer over the filter.  This dust layer allows air to pass through it and the filter while preventing dust particles from passing.  As the dust layers build up, it becomes harder and harder for air to pass through, hence the increase in the pressure drop of the collector.  The filter cleaning cycle is used to remove the top layers of this dust layer; thereby allowing air to pass through easier.

Particles in the Dust Loading

When large particles are in the dust loading, they will block more passages of the air.  However, the layer may not be as uniform, thereby allowing high velocity channels that will allow the smaller particles to pass, with enough velocity to get through the filters.   If the dust loading particle sizes are more equal (smaller) then the dust layer is more uniform, letting less small particles through, thereby increasing the removal efficiency. 

Cyclone Pre-Filter

The installation of a cyclone pre-filter removes the largest particles, allowing only the smallest to pass.  This allows for a more uniform dust layer, thereby increasing the removal efficiency of the filters.

 

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5 Signs Your Dust Collection System Needs a Pre-Filter

Watch the video from the Dust Efficiency Clinic discusses how using a pre-filter will optimize your dust collection system. 

 

If you prefer this valuable information in white paper form, get our whitepaper, Top 5 Reasons to Use a Cyclone as a Pre-filter.

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

Dust collection systems require the proper airflow to operate correctly.  Without the correct air flow, dust will not be removed from collection points and the collection equipment (baghouse, cartridge collectors, cyclones, etc.) will not operate with maximum efficiency. However, if too much air is being pulled through the system, a variety of issues might ensue, such as product being lost, removal efficiency lowered, utility usage increased.

Conventional Way to Measure Airflow

The normal way to measure airflow is to insert a pitot tube in the ductwork to measure the air velocity in an airstream, and then calculate the velocity (and airflow).  This is a manual process that requires a trained individual.  It is time consuming and to a certain degree an art, since the velocity in a ductwork changes depending how close to the wall you are.

Effective Way to Measure Airflow

Obviously, you cannot walk next to a piece of equipment or meter and check the velocity through the ductwork.  However, if you have a cyclone dust collector you can.  Cyclone pressure drops are based on the airflow through them.  The more air you send through a cyclone, the higher the pressure drop.  Each cyclone design has its own equation to determine pressure drop based on the airflow.  With this equation, you can estimate the airflow based on the pressure drop in your cyclone.

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The GPC Dust Collector is an efficient way to handle your dust collecting needs. Simply click below for direct access to the GPC spec.

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Exhaust Fans: The Motive Force of a Dust Collection System

In this video, Aerodyne discusses how system changes and fan performance affect your dust collection system.

 

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

The key function of a collector is to remove the maximum volume of dust from the airstream.  Additionally, an important part of the process is keeping the removed dust from re-entraining.

Baghouses and Cartridge Collectors

Baghouses and cartridge collectors collect the dust on the filters and during cleaning, the material is knocked loose and falls to the hopper.  How well the material falls to the hopper is dependent on the dust that is being collected, the can velocity (speed of air between the filters) in the baghouse, and the design of the baghouse.  

Basically, if the dust is very light and/or irregular in shape, then it might not easily fall to the hopper, instead it might float (like a leaf).  This could cause it to be re-entrained in the airflow and go back on the filter.  If the airflow is very high then the can velocity could hold up dust after cleaning, thereby causing re-entrainment of the dust.  The design of the unit can affect re-entrainment as well.  Some units have the dust coming in the unit below and at a rather high speed, which can increase dust re-entrainment.  Others will have the dust entering from the side of the filters, thereby being at a much lower velocity and out of the path of falling dust.

Cyclones

Cyclones use centrifugal force to push the particulate dust outward.  Most cyclones also use tapered walls to concentrate the dust as it gets lower in the cyclone until it falls into the hopper, while the clean air leaves the cyclone through the center.  The point where the air stops traveling down the walls and begins to travel up the center is called vortex reversal.  Depending on dust size, concentrations, and cyclone design, dust can be re-entrained by the clean air leaving the cyclone.

Wet Scrubbers

Wet Scrubbers are very good at low re-entrainment.  This is because when the dust meets a droplet, they become one larger particulate and then fall out of the airstream easier.  Most well designed wet scrubbers have a mist elimination section that will further collect droplets before leaving the collector.

 

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5 Signs Your Dust Collection System Needs a Pre-Filter

Watch the video from the Dust Efficiency Clinic discusses how using a pre-filter will optimize your dust collection system. 

 

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

As regulations to minimize dust emissions became more stringent, the reliance on filter media became more prevalent.  This means baghouses and cartridge collectors have become the most common dust collectors around. 

Dust Collector Filter

The filters allow air to pass, while dust is captured on the filter surface area.  A filter cake of dust forms, allowing the highest removal efficiency of the filters.  Periodically, the filters will be cleaned to drop dust off the filters/ filter cake, allowing more air through the filters.  The higher the concentration of dust, the faster the filters will require cleaning to keep the pressure drop down.  Every time the filters are cleaned the fabric of the filter wears a bit.  So, if you can minimize the cleaning, then the filters will last longer.

Cyclone Pre-Filter and Dust Collector Filter

Cyclone pre-filters capture a high percentage of the dust before it even gets to the filters; therefore, allowing less clean cycles on the filter media.  Cyclones use centrifugal force to capture dust and droplets and remove them from the airstream.  Unlike filters, the higher the concentration of dust in the airstream, the better the cyclone performs.  Cyclones provide very good removal of larger dust particles, often getting removal efficiencies as high a 99% for 30-40 micron dust particles.  But they do remove lower amounts of smaller particles.  So the cyclone is a perfect companion for dust collection filters as they will remove most of the larger particulate.  This can often be 80-90% of the total dust loading of a system by weight.  The cyclone pre-filter then allows the filters to deal with only the fine dust that gets past the cyclone.  The lower loading of dust on the filters allows the filters to last longer and conserve energy as the cleaning cycle isn’t used as much.

Compact Cyclones

Compact cyclones, such as the Aerodyne GPC, allow cyclone pre-filters to be used in existing facilities where larger (taller) cyclones won’t fit.  The Aerodyne horizontal GPC cyclone provides one of the most compact designs - often ⅓ the height of traditional cyclones.  This can often allow the cyclone to be installed inside or in smaller areas of an existing system.  Traditional cyclones typically require outdoor installation, unless the facility has high ceiling.

So if your filter dust collection system is experiencing operational issues, look into compact cyclone pre-filters as a possible solution before you decide to scrap your current unit and install a new one.

 

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5 Signs Your Dust Collection System Needs a Pre-Filter

Watch the video from the Dust Efficiency Clinic discusses how using a pre-filter will optimize your dust collection system. 

 

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

Not only do NFPA regulations require a DHA (Dust Hazard Analysis) to be done on all systems that might have explosive dust, they also require the DHA to be updated every 5 years and whenever the system changes. 

Simple Changes in Documentation

The change can be adding , removing,  or changing equipment or changes in the material going through the system. 

Since a DHA has already been done, the scope of the change is much less.  Using the information in the original DHA, the equipment that is being changed can be analyzed to make sure it complies with NFPA.  This report will then be added to the existing DHA so that a record of change is documented.  Usually the report is considered a mini-DHA or System DHA. 

The mini-DHA or System DHA often can be conducted by a 3^rd party consultant working with the equipment manufacturer.  This usually can be done without a site visit.  Aerodyne offers the Mini-DHA/ System DHA for our cyclone separators.

 

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Are you in compliance with the 2018 version of NFPA 68?

Simply click the button for direct access to the webinar to learn more about how to these recent changes may require modifications to your system.

 

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

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To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

 

We all know that getting the oil change in our car regularly is important to the car being able to get you around when you need it.  However, your dust collector needs regular maintenance too.  The dust collector system consists of hoods, ductwork, air-material separators (cyclones, baghouse, cartridge collectors, wet scrubbers, etc.), explosion protection equipment, airlocks, instrumentation, and exhaust fans. 

All of these items should be checked at least once a year to make sure they are operating correctly.  The following points briefly describe what each piece of equipment needs:

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1. Hoods

• Visual inspection to make sure they haven’t been damaged during the year.
• Measure airflow velocity to make sure they are collecting the design airflow.
• If a local damper is located by hood for balancing, make sure it is operable and in the correct position.

2. Ductwork

• Visual inspection to make sure no holes have developed.
• Measure air velocity through ductwork to make sure designed airflow is correct.
• If possible, visual inspection of duct internal to make sure dust isn’t building up.

3. Air Material Separators

• Measure pressure drop across the separator to see if it is within parameters.
• Inspect cleaning process (baghouses and cartridge collectors) that they are operating properly (timing, valves opening, air pressure, etc.). See operations and maintenance manual.  Often time, listening to the system will let you know if it is operating correctly.
• Monitor recycle line pressure and overflow in wet scrubbers.
• Visual inspection of vessel walls to be sure there are no holes.

4. Explosion Protection Equipment

• NFPA requires yearly inspection, following the manufactures manual is very important so the explosion protection equipment will protect the facility, equipment, and workers as it was designed.
• Some explosion protection equipment such as chemical suppression should be done by factory trained personnel.

5. Airlocks

• Rotary valves
  • Should be checked to see they are still spinning
  • Bearings should be greased and temperature measured to make sure they aren’t overheating
  • On explosive applications the rotor clearance should be measured to make sure it still complies with NFPA 69.
• Pneumatic valves (slide gates, double flap valves, etc.)
  • Valves should be tested to make sure they are still operating as designed.
  • Air pressure should be measured, to be sure it is still within design parameters.
• Motorized valves (rotary valve, double flap valves, etc.)
  • Bearings should be greased
  • Bearing temperature should be measured to be sure they aren’t overheating
• Trickle valves
  • The sleeve should be inspected to be sure it is still sealing
  • During operation confirm that material is still draining and material hasn’t bridged above it.

6. Instrumentation

• Level gages, pressure gages, VFDs, pH meters, zero speed switches, etc. all have different maintenance requirements.
• Follow the manual of the specific model for maintenance and inspection.

7. Exhaust Fans

• The fan housing should be inspected to make sure no holes are present.
• The voltage and amps should be measured to make sure it is operating at its design condition.
• The bearings should be greased and temperature checked to be sure they aren’t overheating.
• The fan’s vibration should be checked along with checking to see if any abnormal noise is emanating from the fan.

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To learn more about which dust collector, please contact our experts at 440-543-7400 or visit our website: www.dustcollectorhq.com.

To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click below to start with a free 20-minute phone consultation by clicking the button.

 

Click below and watch our video to identify five signs that may diagnose a sluggish system so that you can return your system to full efficiency.

A simple dust collection system is composed of the exhaust fan, dust collector (cyclone, baghouse, cartridge collector, wet scrubber, etc.), ductwork, and hoods.  An issue with one of these components could cause your dust collection system to fail or not work as designed.  However, the dust collector is usually the most complex component and the most likely to develop issues, but is often the most neglected.  Just like an automobile, proper maintenance of a dust collector could save a whole lot of issues in the future.

A variety of issues can develop in the operation of dust collectors.  We will discuss baghouses specifically, but cartridge collectors have very similar issues, while cyclones and wet scrubbers have their own set of items that need attention.

Plugged filters.  Bag Filters are the primary component in dust collection.  If they aren’t operating correctly, the dust collection will not be operating properly.  The filters can fail if they get plugged up or develop holes.  When plugged up, they will not let the proper amount of air through, which will cause the airflow through the system to decline; thereby, picking up less dust at the pickup points.  Plugged filters can be spotted by monitoring the pressure drop across the bags or noticing less air movement at the pickup points.  When filters are plugged up, they should be replaced and quickly. 

Holes in the bag filters allow dust past the filters; thereby, decreasing the removal efficiency in the system.  This can cause you to violate your EPA permit, cause damage to the exhaust fan and/or cause issues with the neighbors.  Holes in the filters can be spotted by bag break monitors, stack testing, or noticing dust in the exhaust.  When bags are broken they should be replaced, however, it is often difficult to identify which bag has the hole so often times multiple (if not all) bags should be replaced.

Inspect these other components.  Baghouses also contain many supplementary items that help them operate effectively.  These can also develop issues which causes the system to fail.  These items include solenoid valves, poppet valves, control panel, bag support cages and venturi, diffuser, hopper and airlocks. These items should be inspected, cleaned and components replaced if necessary.

Other factors to consider:  Failure in the cleaning system will cause high pressure drop.  Damage to the cages could cause holes in the bags.  Damage to the diffuser will cause some bags to plug up faster than others.  Damage to the hopper or excess dust in the hopper will cause higher dust concentrations that decreases removal efficiency.  An inoperative or inappropriate airlock will cause dust build up in the hopper and/or air leakage.

A yearly inspection of your baghouse will help you identify these issues before they develop. This will help your dust collection system operate at peak efficiency and as it was designed.  And as with your automobile, preventative maintenance ends up saving you money in the long run.  If your baghouse stops operating you will have to do an emergency repair or, as is most often the case, it will gradually decrease in its efficiency without you noticing. You will then be wasting your money on operating a system that isn’t effective.  And if you are inspected, you could be fined.

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