We all know that if we don’t regularly maintain our cars, we will end up having issues in the future. If we forget to change the oil, change the brakes or get a tune up, it will eventually catch up to us. Why do we think our dust collection system is any different? Dust collectors are made of various pieces, all of which have to be operating correctly for the system to operate as desired. Usually, a dust collection system consists of the dust collector, exhaust fan, ductwork, and hoods/pickup points. Additional accessories such as airlocks, controls, instrumentation, and dampers all can affect the operation of the system.

The following questions with quick explanations will help you evaluate your dust collector. If after going through this guide you think your dust collector needs a tune-up, contact a local expert or Aerodyne Environmental and have them come in to help you get your system working properly.

Pickup Points

1. Are the areas near the pickup points dusty? Is there any dust in the air, is it hazy, or is breathing in the area a bit difficult?

2. Are there dust piles around the area? Dust piles and layers of dust can become airborne and if the dust is explosive, it can lead to an explosion causing significant damage and injury.

3. Can you feel airflow being pulled into the hood or pickup point?Often times, dust collection systems will be modified and this could cause a loss of airflow at other areas in the system.

4. Did the dust collection system ever work as expected? Sometimes a dust collection system has never fulfilled expectations. This doesn’t mean that changes can’t be made to get it working better.

Ductwork

1. Does the ductwork have holes? Holes allow air to leak into the system, this will cause less air to be picked up at your hoods and pickup points.

2. Are you plugging up your ductwork? Plugged up ductwork is caused by low air velocities through the ductwork. This will cause low airflow at your hoods and is an explosion danger.

3. Have you added or de-commissioned pickup points on your system? Adding or removing pickup points can cause the system to be out of balance. If you have done this without re-evaluating the whole system, your system may not be operating correctly.

Dust Collector

There are a variety of different dust collectors available—baghouse and cartridge collectors, cyclones, and wet scrubbers. Each one of them has different things to look at. We will only address a few of them here. Contacting a dust collection expert such as Aerodyne Environmental can help you diagnose issues.

Baghouse and Cartridge Collectors

1. When was the last time you changed filters? Some customers have to change filters twice a year, others haven’t changed them since they were installed. Both examples could have issues.

2. What is the pressure drop across your filters? Pressure drops over 6” W.C. usually tells you that you need new filters soon. A low pressure drop can mean that you have holes in your filters or haven’t properly developed a dust cake on the filter.

3. When was the last time you did a maintenance check on your dust collector? If you haven’t done it in the past year or two, it might be time. Filters, tube sheets, diffusers, air valves, manifolds and a variety of other items can all develop issues.

Cyclone

1. Have you checked your cyclone for holes? Cyclones often wear faster than other dust collectors, so a yearly check for pin holes or wearing is always a good idea.

2. Do you have a filter after your cyclone? Since cyclones have lower removal efficiencies than most other dust collectors, if your cyclone doesn’t have a filter afterward, you might want to monitor the emissions regularly to make sure you’re not emitting too much dust.

Wet Scrubbers

1. What is the pressure drop through the wet scrubber? Higher than normal or lower than normal pressure drops always tell you something is happening. Higher pressure drops usually means that dust is building up in the system. Lower pressure drop usually means that less airflow is going through the system.

2. Do you monitor your water usage and the particulate loading of the overflow? The overflow stream of the wet scrubber removes the particulate and the dissolved solids from the system.

3. Are you taxing your water treatment plant? Water treatment is expensive so if you can lower the amount of water going to it, you could save money.

Exhaust Fan

The exhaust fan usually provides all the motive force in a dust collection system; therefore, if the fan isn’t working properly the whole system will be having issues.

1. Is the fan vibrating excessively?
2. Is the fan making more noise than usual?
3. Are the bearings in the fan running hot?

Excessive vibrating and unusual noises can mean that something is wrong with the fan. Damage to the impeller or dust build up on the impeller could cause this. Some fans do get unbalanced over time and could cause the fan to stop working. A bearing running hot could be caused by an issue with the fan or an issue with the bearing. Hot bearings, while unlikely, have been known to cause fires or explosions if all the conditions are right.

Miscellaneous

Other items to check on your dust collection system include dampers, airlocks, controllers and instrumentation. Dampers not operating correctly, or accidently opened/closed can cause operating issues. Airlocks under dust collectors can cause air leakage into the system or prevent dust from leaving the system. Controllers and instrumentation can cause the system to shut down, or provide wrong reading, thereby affecting the operation of the system.

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. Our engineering team is available here to answer any questions you have about improving or evaluating your setup. 

The post Questions to Ask When Evaluating Dust Collection System | Aerodyne first appeared on Aerodyne Environmental.]]> https://www.dustcollectorhq.com/dust-collector-hoppers-are-not-for-material-storage/ Fri, 23 Dec 2022 19:45:00 +0000 https://www.dustcollectorhq.com/dust-collector-hoppers-are-not-for-material-storage/ Dust Collector Hoppers Are Not For Material Storage

One common mistake operators make in dust collectors is to use the dust collector hopper to store material. The hopper in a dust collector isn’t designed for this. Instead it is a temporary home for the dust collected while the material is being removed. This period should be as short as possible for the following reasons:

• The dust collector isn’t designed to support a hopper fully filled with material. The added weight could cause structural issues with the vessel and the supports.
• As the hopper gets fuller, there is a greater chance that material will be re-entrained into the airstream, thereby causing a lower removal efficiency, increased wearing on the housing, filters, etc.
• Large amounts of dust in the hopper could become airborne during an incident, which could fuel an explosion in the dust collector. Removing the material from the hopper isolates the material storage from the dust collector.
• Storage in the hopper could cause bridging or rat holing of the material. This could cause the material to backup into the separation zone (example: begin covering filters). This will cause major operational issues in the dust collector and decrease removal efficiency and airflow through the system. 

The Solution: Airlock Valves

So when you are operating your dust collector, be sure to remove the dust collected in the hopper as soon as you can. Airlocks such as rotary valves, double dump valves and trickle valves (ex. Aerodyne’s Vacu-Valve) are ideal for keeping the process isolated from the outside while also allowing the collected material to leave the collection hopper.

---

When it comes to improving efficiency and safety, there is no substitute for an on-site inspection by an experienced expert. To learn more about the right dust collection solutions for your application, please contact our engineering team at 440-543-7400, or by clicking here. 

The post Dust Collector Hoppers Are Not For Material Storage | Aerodyne first appeared on Aerodyne Environmental.]]> https://www.dustcollectorhq.com/5-signs-you-need-a-checkup-on-your-dust-collection-system/ Mon, 31 Aug 2020 22:37:00 +0000 https://www.dustcollectorhq.com/5-signs-you-need-a-checkup-on-your-dust-collection-system/ 5 Signs You Need A Checkup On Your Dust Collection System

The post 5 Signs You Need A Checkup On Your Dust Collection System | Aerodyne first appeared on Aerodyne Environmental.]]> Dust collectors are required in facilities for multiple reasons. After installation, they are often forgotten about until something isn’t working right.  In order to fix the problem, the system has to be almost re-engineered to figure out what the design originally was. The following things are signs your dust collector isn’t working how it was designed and you need to perform a checkup.

Area around the air inlets are dusty

The dust collector inlets/hoods capture the dust from your process. If you are noticing greater dust in those areas, then your dust collector isn’t operating correctly or something changed in the process. Either way, having an expert come in and look at the system is your 1^st step to solving the issue.

High pressure drop through the dust collector

Baghouses and cartridge collectors use filters to capture the dust. They are cleaned regularly to prevent dust buildup, but they will plug over time. Once the dust builds up, less air will be pulled through system thereby allowing more dust to escape. You might not notice this change at the hoods, but the pressure gages across the filters will tell you when the pressure drop is high.

Material collected in the dust collector is less than before

As less air is being pulled into the system, more dust is escaping the system, which means less dust is being collected by the dust collector. One way of noticing this is when you’re not hauling away the dust from the hopper as much. An example would be normally you are replacing the 55 gallon drum once per week but now it’s once every two weeks.

Equipment in the area requires high maintenance

Dust can coat equipment and get into crevices. This can cause increased wear on rotating equipment, contaminate fluids, and plug air filters. All of these can cause an increase in equipment break downs. Equipment that is wearing down usually isn’t operating at its highest efficiency, thereby needing more energy. So if you are noticing an increase in equipment maintenance in a specific area, the dust collector might not be working as it should.

Workers are complaining about dusty areas or are calling off work more often

Dusty air can cause issues with the workers in the area. Dust can cause inflammations in the respiratory system which can cause people to be more susceptible to sickness. Workers might complain about the dusty air or just get sick more often.

Usually, combinations of these signs are happening at the same time. However, some might be more noticeable than others. So if you are seeing one of these signs, check for the others and then schedule a dust collector evaluation to get your system back into working order.

---

Bridging Dust?

Try the Aerodyne Mighty Whopper.

Aerodyne’s Mighty Whopper rotary valve has over-sized rectangular inlet and outlet. 

 

---

5 Signs Your Dust Collection System Needs Maintenance

Is your dust collection system working at peak efficiency? A quick, do-it-yourself examination may identify symptoms that your system needs a check-up.

---

Interested in more dust collection and material handling literature? Visit Aerodyne’s homepage for our full resource library. Alternatively, if you’d like to talk to a member of our engineering team about your own application, click here.

The post 5 Signs You Need A Checkup On Your Dust Collection System | Aerodyne first appeared on Aerodyne Environmental.]]>

Cyclones do not stand alone in most applications; rather, they require additional equipment to function properly. Depending on your specific application, this equipment can include an airlock, exhaust fan, explosion protection, instrumentation, insulation, vibrator, and even ductwork. Moreover, a cyclone can be purchased either as a complete system with all the necessary equipment or by itself to be integrated into an existing system. In either case, the system is then assembled by the end user or a third party. Often, the total cost of the accessory equipment exceeds that of the cyclone itself. Below is a brief description of these potential accessories and how they impact the cyclone’s performance.

Airlock

An airlock is essential for the proper operation of a cyclone.  It isolates the cyclone from the outside atmosphere.  Without it, material will fly out the bottom or get re-entrained in the system.  Airlocks could be a simple extended hopper (55 gallon drum), rotary valve, or specialized valves like the double dump valve or trickle valve.  Special designed valves are available for quick cleaning applications and explosive applications.

Explosion Protection

Explosion Protection is a very important consideration for dust collectors as about 70% of dusts are explosive. The equipment that protects against explosions can add significant cost the cyclone.  Explosion protection equipment such as explosion vents, isolation valves, chemical suppression, and isolation systems can all quickly increase the price of a cyclone.  This equipment is required for explosive applications. 

Exhaust Fans

Exhaust fans are required on every dust collection system. They provide the motive force required to pull air through the system.  When selecting the fan, be sure to take into account all ductwork and equipment.    It is best to install the fan downstream of all dust collectors so that the most efficient impeller designs can be used.  This will save money on operational costs.  However, if the fan needs to be installed in high dust areas, there are impellers designed for these operations.

Instrumentation 

Instrumentation for cyclones are rather simple compared to other dust collectors. The main instrumentation used on cyclones are differential pressure gages/transmitters and level switches for the hoppers.  Explosive applications can have special instrumentation and some applications will monitor temperature and humidity for equipment downstream of the cyclone.  But for most standard cyclone applications, differential pressure is the only recommended measurement.

Insulation, Heat Tracing, Steam Jacketing

Insulation, heat tracing, steam jacketing are required for special applications. These can add significant expense to the cyclone.  Insulation and heat tracing can be done at the fabricator but usually are done onsite to prevent damage in shipping and installation.  Steam jacketing must be done in the design and fabrication phase and can add significant cost to the cyclone.

Vibrators or Air Jets

Vibrators or air jets are used in applications where material tends to bridge in the hopper. Typically, vibrators can be added after installation and help prevent the hopper from bridging. Similarly, air jets blast air into the hopper to break up any bridges, allowing material to flow smoothly through the airlock. Ideally, however, the connections for these devices should be included in the cyclone design and installed on-site from the start.

In summary, cyclone design and costs depend on the size and construction needed for your specific application. Furthermore, special applications may require expensive equipment and design modifications, which can significantly increase the overall cost. Therefore, when selecting a cyclone for your application, it is important to consider all factors in your cost estimate to ensure an accurate and realistic budget.

To learn more about the right dust collection solutions for your application, 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 here to talk to a member of our engineering team today. 

Level Switches

That is where level switches in dust collector hoppers fit in.  An airlock works by allowing dust from the dust collector to leave the vessel while preventing air from leaking in or out of the system.  Some airlocks operate by emptying the hopper as soon as dust falls and some require a buildup above them to help seal the valve and provide motive force. 

The main thing is, that dust often times will not constantly be falling through the valve.  This means that walking next to a vessel won’t always tell you if the airlock is operating correctly. 

Installing a level switch in the hopper will help.  The level switch measures the amount of material in the hopper and if too much is in the hopper it will provide a signal (alarm).  This will tell maintenance that the airlock is not operating correctly and it needs to be investigated.  Depending on the system’s controls, the alarm can be a local alarm (light and/or horn) or feed into the central computer.

Dust collection systems can range from being fairly simple to extremely complex. 

It’s important to know that you have the proper system for your application. Some questions always come up when looking at dust collection systems.

To make life easier, we have put together some common questions we get asked along with answers and explanations. Have a look.

Download our Dust Collector FAQ Guide (Volume 1)

Download our Dust Collector FAQ Guide (Volume 2)

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

There’s no substitute for an onsite inspection by an experienced expert to increase the efficiency and safety of your dust collection system. Our engineering team is available to answer any questions you have about your application. Please fill out our contact form to get started.

First, dust re-entrainment could increase the concentration of the inlet dust loading, thereby letting more dust through the dust collector and increasing the wear and tear on the components.  Re-entrainment could also cause air that has already been cleaned (as in a cyclone) to be contaminated, thereby decreasing the unit’s overall removal efficiency.

Another, more serious issue would be in explosive dust applications.  Dust collection in the hopper will increase the amount of material able to fuel an explosion if there is a source of ignition. It could also increase the risk of combustion by increasing the concentration of explosive dust in the air. 

If you have cyclone in an area where it experiences significantly lower dust loading than the Minimum Explosion Concentration (MEC), then you might think that you don’t have to install explosion protection.  However, if you are storing dust in the hopper, your actual dust loading could be higher than the MEC.

The best procedure is to keep the dust in the dust collector hopper to a minimum.  You can install a level gage on the hopper that will let you know if the material has built up and is ready for discharge. The gage will alert you that it is time to clean out the hopper and check your airlock for issues. You can install a timer that opens the valve periodically.  With some types of dust, a trickle valve such as the Aerodyne Platypus valve will automatically allow material to pass once it has built up high enough above the valve.

Minimizing material storage in the hopper will keep your removal efficiency as high as possible, decrease wear and tear, and also minimize explosion risks.

The best way to keep your dust collector working properly is to have a professional maintenance crew inspect and maintain your dust collectors. Not only does this open your maintenance staff for other work, it allows them to use their experience to keep your baghouse operating at peak performance. Fill out our Dust Collection System Evaluation form.

If the dust collector is under negative pressure (fan after the dust collector), then air will leak into the system from the opening.  This will re-entrain dust that has already been removed from the process air.  This will also decrease the air being captured at the pickup points (hoods), thereby making the dust collection system less effective.

If the dust collector is under positive pressure (fan before the dust collector), then air will blow out of the opening.  This will cause the dust being captured to fly out of the dust collector and scatter on the floor and re-enter the facility air.  Installing an airlock will prevent the above conditions.

Some applications have limitations on humidity, temperature, oxygen levels, etc.  If an airlock is not installed, there will be no way to control the conditions, as the outside environment will leak into the system.