Pulse-on-demand controllers allow you to clean your filter less often. Less pulses helps you save compressed air and reduces wear and tear on the filters. Cutting down on compressed air means less electricity is required in the compressors and less wear and tear on the filter means they last longer.

Install a cyclone pre-filter

A cyclone pre-filter will help remove dust before it gets to your filters. This means that the dust loading on the filters will decrease, which helps extend their life by requiring less cleaning and plugging them up less. The cyclone can also allow you to recycle the material without contamination and possibly increase the total removal efficiency of the system.

Monitor airflow in the dust collection system

Dust collection systems are designed to capture dust and they should be operating at design specifications. By monitoring the airflow, you are confirming that the unit is operating correctly. If the airflow is off from its design condition, then you will not be capturing the material that it was designed to capture. Measuring the airflow is similar to measuring the temperature in an oven. Without measuring it, you won’t know if you are at the correct performance and the end result may be off.

Install Aerodyne Vacu-Valve (if appropriate)

All dust collectors require airlocks. The standard airlock in the business is a rotary valve. Rotary valves require a motor powered by electricity. An Aerodyne Vacu-Valve has no moving parts so it just uses the vacuum already in the system to provide the airlock and gravity to pull the material through. The valve is limited in that the material can’t bridge and it can’t be explosive.

Clean and reuse filters

The normal procedure when replacing filters is to tear them out and throw them out when they are plugged. However, if you are monitoring the system closely you can schedule them to be removed and cleaned before they plug up and not require a new set each maintenance period. Ideally, it would be to have one full set as a spare so the crew can remove the dirty ones and install clean ones at the same time. You will then have time to clean the dirty filters and replace any that are damaged or beyond cleaning while you are operating.

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Have a question or want to connect with a member of the Aerodyne engineering team about your application? We’re available at 440-543-7400 x 235, by email at dc@dustcollectorhq.com, and then through our contact form here.

Dust collection filters such as the bags in baghouses, cartridges in cartridge collectors, and HEPA filters all filter out dust particles by collecting them in between their fibers. Dust builds up on the bags and cartridges to form a filter cake over the filter further restricting the ability of dust particles and airflow to pass through the filter. This restricting of airflow causes a pressure drop (resistance) which is directly related to the amount of dust built up on the filters. As the pressure drop increases, the airflow through the collector will decrease. Most baghouses and cartridge collectors have cleaning cycles which remove some of the dust from the filters keeping the pressure drop low.

The cleaning process on the filters usually consists of blowing higher pressure air through the filters, thereby causing it to expand slightly. This knocks off some of the top layer(s) of the filter cake which lowers the pressure drop through the filters. Other units have the filters connected to a mechanical shaking system. The airflow through the filter will be stopped during the cleaning process. The mechanical shaker system will gently shake the filters dislodging the dust to fall into the hopper.

Even with these cleaning functions, the dust collection filters will eventually plug up and significantly decrease the amount of air they allow to pass. This will starve the pickup points of airflow, allowing dust to escape and never enter the collection system. Depending on the application, this can happen within months or years of putting in new filters. The process of replacing the filters usually requires the system to be turned off. Cartridge collectors are usually easier to replace than bag, but either way the time and labor it takes to change are significant.

Ways to Extend the Life of Dust Collection Filters

It is therefore very advantageous to extend the time between filter replacements. The following are a few ways to extend filter life.

• Install a pre-filter before the dust collector. The greater the concentration of dust getting to the filter, the faster the filter will plug up or fail. So if you can lower the dust concentration, you will extend the life of the filters. Pre-filters include cyclones and dropout boxes. Pre-filters remove most of the larger particles, leaving only the smallest to be handled by the filters.
• Install pulse-on-demand controllers. A pulse-on-demand controller monitors the pressure drop across the filters. And when the pressure drop gets too high, the unit will activate the cleaning process until the pressure drop falls below a shutoff point. This extends life by preventing unnecessary cleaning of filters which can cause holes to develop in the filters. It also can save money on compressed air and keep the airflow within desired range.
• Install different filters. Not all filters are the same. Some filters are designed to minimize issues with wet dust. Others have higher temperature ratings so they won’t degrade. If you are replacing filters too often, contact your filter supplier or system manufacturer to see if there are other filters that are more suitable. These special filters are more expensive, so it might be prudent to look at adding a pre-filter and pulse-on-demand controller to extend life even further at the same time.
• If you are plugging up the filters with hygroscopic dust, check the collector housing for leaks that might allow humidity into it. Also, check the compressed air supply to make sure humidity isn’t being added to the system.
• Install insulation on the dust collector if you have high humidity. Insulation will help prevent water vapor from condensing at night or during winter, thereby preventing water droplets from damaging the filters or causing dust to plug up in the filters.
• Install a spark arrester before the dust collector. Depending on the process being vented, sparks can be pulled into the dust collector which, thereby cause the filters to catch on fire. Installing a spark arrester prevents this. Often times a pre-filter (cyclone or dropout box) provide the same protection.

If you are replacing dust collection filters too often, think about making some of the above changes to your system the next time you are due to replace filters. That way, you can extend filter life and operate for longer periods without maintenance.

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For more dust collection and material handling literature, visit the library tab on our website at www.dustcollectorhq.com.

To improve efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. Click here to speak with a member of our engineering team about your application, anytime. 

For many years, pulse-jet baghouses were cleaned by simple timers.  The timers would start the cleaning cycle every so many minutes.  You would be able to change how often your filters are cleaned by changing the time between each cleaning.  This design makes sure that the filters are cleaned regularly, whether they need to be cleaned or not.  The main issue with this is that every time a filter is cleaned, it increases the chances of it failing.  Filters are cleaned by pulsing high pressure air into the filter.  This expands the filter, which causes the top layers of dust to fall off.  But that expansion can also cause holes or rips in the filters.

Pulse-On-Demand Controller

So it would be beneficial to minimize the cleaning of the filters to only when it’s needed.  The pulse-on-demand controller does just this.  It measures the pressure drop across the filters.  When the pressure drop gets over a certain amount, it will begin the cleaning process.  Many of these controllers also have “bag break” technology, which will tell you when one of the filters has a hole.  You will then be able to replace the filters only when they are needed.  Some controllers can even isolate the row where the broken bag is located, so you won’t have to replace all the filters.

Installing a Clean-on-Demand controller, “bag break” technology, and cyclone pre-filters (Check out other Aerodyne blogs for more info) can help you decrease the maintenance on your filters, extend filter life, and lower operating costs (less air usage).

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. Talk to a member of our engineering team here. 

While Aerodyne doesn’t manufacture baghouses or their controllers, it seems like we’re always working with them. However, as we like to say, the pulse-on-demand controller is the wave of the future.  Sure, the old baghouse controller is still functional, but the rising cost of energy and the growing concern about waste make the pulse-on-demand controller the ideal choice.

The pulse-on-demand controller measures the pressure drop across the filters.  When the pressure drop gets above a certain amount (as set by the user) the cleaning system will automatically start up.  It will continue to clean until the pressure drop get below a certain amount (again set by the user).  This process then repeats itself throughout operation.

This means that you won’t have to clean your filters unless you need them, which makes everyone’s life easier, except maybe for the bag manufacturer!  Less cleaning also means that your filters will last longer, and you’ll save extra money otherwise spent using more compressed air.

To increase the time between required cleanings, you can also add a cyclone pre-filter before the baghouse section to decrease the loading on the baghouse, so that it takes longer for the filter’s pressure drop to increase. This way, your bags will last longer while your compressor works less, saving your facility money.