Dust Collection and Valves Blog

Tom Hobson

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5 Ways to Go Green in Dust Collection | Aerodyne

Posted by Tom Hobson on Sep 29, 2022 3:00:00 PM


  1. Use pulse-on-demand controller for baghouse and cartridge collectors

    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.
  2. 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.
  3. 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.
  4. Install Aerodyne Vacu-Valve (if appropriate)

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Topics: Cyclone Pre-Filter, vacu-valve, cleaning baghouse filter, pulse-on-demand controller

5 FAQs of Small Cyclone Technology | Aerodyne

Posted by Tom Hobson on Aug 29, 2022 4:15:00 PM

Smaller cyclones avoid many of the disadvantageous and time-intensive aspects of larger cyclones, including those relating to installation and regulatory compliance. Here are the five frequently asked questions about using small dust-collection cyclones.

How does GPC technology shrink the size of a cyclone without hurting efficiency?

Cyclone dust collectors are designed with a descending cone. Particulate laden air enters an inlet at the top and rotates down, exiting at the bottom while clean air is exhausted from the top. Dust is thereby separated from the airstream for recovery or later disposal. Distinct cyclones have emerged on the market that use GPC technology. These changes the shape and structure of the cyclone to make it just as efficient as much longer cyclones for the same volume of airflow passing through them.

GPCs have a ground plate located inside the cyclone. It intercepts dust in the airstream, causing particulate to divert toward the hopper, and also to lose momentum and fall out of the airstream. It also intercepts the airflow, thereby preventing dust re-entrainment from the hopper. What’s more, this technology is less dependent on gravity, enabling horizontal installation of the cyclone—very helpful where overhead space is limited.

Can a small cyclone reduce the cost of explosive dust applications?

More than 70% of industrial dusts are explosive, so venting for explosive dust is a common feature of plants. Potentially explosive dust requires the use of an explosive vent and ductwork in strict compliance with NFPA (National Fire Protection Association) standards. In general, in the event of an explosion in a cyclone, the goal is to control the location of the explosion, i.e. outside the building and away from people. Often it is more practical to locate the cyclone outside. This adds additional costs for a concrete pad and long ductwork runs. It also introduces the effect of weather that can shorten the lifetime of equipment.

Are horizontal cyclones easier to clean?

Standard cyclones may be time-intensive to clean, owing to flanges and small access doors.

A horizontally installed GPC cyclone typically features a wide removeable backplate, allowing it to be cleaned in a fraction of the time that a traditional cyclone requires. The bolts on the backplate can even be replaced with quick-disconnect clamps, further reducing maintenance time.

How can point-of-use dust collection cut costs?

Small dust collection cyclones are easier to install at the point of use, i.e. directly adjacent to a dust production area. This allows reclamation before the dust is mixed with other dusts in a central dust collection system. It’s always better to recover as much of your product as possible so you can sell it or reuse it, instead of letting it go into costly filters.

Point-of-use dust collection also minimizes buildups of material in the ductwork, as much less dust is travelling through the ducts to reach the main collector.

Can small GPC cyclones be used on mobile dust collection applications?

Any mobile dust collection application needs to maximize the available space and minimize weight. A big cyclone takes up precious space on a vehicle. Often a cyclone must be lowered before travel, to fit under obstructions such as bridges, and then raised to a vertical position when it gets to the job site.

Compact enough to fit on semi-trucks, trains, and ships, horizontal cyclones don’t need to be raised and lowered. The cyclone will already be in operational position while also easily fitting under bridges or into small spaces.

Aerodyne experts make a big deal out of small. For a consultation about the cost savings of small cyclones, or to discuss maximizing the efficiency of your current system with NFPA compliance, contact the experts at (440) 543-7400 or DC@DustCollectorHQ.com.


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Topics: horizontal cyclone, GPC Cyclone, splitScream Cyclone

High Temperatures Are No Problem for Cyclonic Dust Collector | Aerodyne

Posted by Tom Hobson on Jul 29, 2022 11:15:00 AM

A manufacturer of grinding wheels in Niagara Falls, N.Y., needed to replace an existing dust collector used to collect dust coming off a rotary kiln. Initially, a bag house collector was considered to be the obvious solution. However, because the problem involved high temperatures – 700° F and above – specific efficiency requirements, moisture content problems, and future maintenance issues, the purchase of an Aerodyne SplitStream grinding dust collector was justified.

Aerodyne SplitStream Cyclone Dust Collector

The volume of gases being handled was estimated at 4,000 CFM at 700°F, according to the specifications of their previous cyclone. Using this information, a S4500 SplitStream grinding dust collector was selected and installed.

When the collector was started and the flows were checked, the company discovered that only 2,500 CFM at 500°F was needed to ventilate the kiln. Even at this lower-than-expected inlet flow rate, the results were excellent. No visible carry-over was detected, and the SplitStream dust collector captured materials much finer than previously collected.

The plant was satisfied it had made the correct decision and avoided the headaches and maintenance issues of a bag house. After several   months in operation, abrasion   wear   was   not   evident  on   the   collector. Consequently, the company ordered two more Model 4500 SplitStream grinding dust collectors.

The lack of a filter media and Aerodyne’s unique design make the SplitStream collector perfect for applications involving high temperatures and abrasive materials.

The Aerodyne SplitStream dust collector achieves high efficiency by forcing dirty gases into a powerful centrifugal motion. The centrifugal action throws dust particulate out of the gas stream. A secondary air stream carries the dust particulate to the hopper, keeping dust away from the collector walls and reducing sticking and abrasion. As a result, the SplitStream dust collector virtually eliminates maintenance problems common to other types of cyclones. The prevention of particulate contact with external walls is a major factor in the unit’s ability to achieve high efficiency ratings.


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.

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Topics: dust collector, horizontal cyclone, GPC Cyclone, splitScream Cyclone

Questions to Ask When Evaluating Dust Collection System | Aerodyne

Posted by Tom Hobson on Jun 24, 2022 10:30:00 AM

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?
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.
  1. 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.


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.

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Topics: dust collector, hoppers, horizontal cyclone, GPC Cyclone, Dust Collector filters, arirflow

Top 5 Applications Where Standard Dust Collectors Fail | Aerodyne

Posted by Tom Hobson on May 31, 2022 1:30:00 PM

Dust collection is often one step in a series of steps used to treat an airstream or process stream. Often times the airstream will require heating or cooling, gas scrubbing, and/or dilution of gas stream, etc. All of these processes usually require additional equipment to work in tandem with the basic dust collector. Adding additional equipment is not only expensive, but it consumes floor space and often purchasing new equipment will get overlooked simply due to lack of space to accommodate it.

Standard dust collectors often have operational issues with abrasive, sticky, and fibrous dusts. Standard pre-filters for these applications can have high maintenance costs, however without a pre-filter the particulate will often foul or erode the process equipment. Sticky dust will plug filters and foul heat exchangers. Abrasive dust will prematurely wear heat exchangers and dust collectors. Fibrous dust will foul in tight areas. Wet scrubber applications can experience higher water usage when the particulate amount increases.

There are 5 applications that utilize standard dust collectors:

1. Temperature Adjustment of an Airstream

The SplitStream cyclone uses a secondary airstream to convey the dust from the walls of the cyclone down into the hopper for dust collection. The secondary airstream can be used to heat or cool the primary airstream before it is vented outside or fed to other process equipment. The two airstreams will combine in the cyclone and they will leave together at a uniform temperature.

2. Abrasive Dust

Abrasive dust will shorten process equipment’s life span by eroding away the walls of the equipment. Due to the design of a standard cyclone, the lifespan is shortened quicker. A standard cyclone is designed so that the dust is conveyed to the outside of the cyclone, where it hits the walls and fall into the hopper. Abrasive dust will also wear out filter bags, the inlet distributor, tube sheets, and the baghouse walls.

3. Sticky and Hygroscopic Dust

Sticky and hygroscopic dust can also cause issues with standard dust collectors and cyclones. Sticky dust will accumulate in any dead zones in standard cyclone. This causes a gradual reduction in the internal volume of the cyclone, and changes the geometry of the cyclone, which could cause a change in the removal efficiency of the unit.

4. Fibrous Dust

Fibrous dust causes many issues for standard dust collectors. The fibrous dust floats in the airstream and often will be re-entrained back in to the air exiting the cyclone. In baghouses and cartridge collectors, fibrous dust when cleaned off the filters, will float in the dirty air plenum. This increases the concentration of the dust in the unit. The dust will not settle into the hopper to be removed from the system. Overtime this will cause the dirty air plenum to plug up, thereby plugging up the dust collector.

5. Oxygen Reduction

Many dusts are explosive and with growing scrutiny of new and existing operations by inspectors and insurance companies, existing processes are being found that require explosion protection. One way of protecting from explosions is to prevent an explosion from ever occurring by lowering the oxygen level of the system below the Lower Explosive Level (LEL). This is done by adding an inert gas such as nitrogen to decrease the concentration of oxygen.

Aerodyne’s SplitStream cyclone offers a strong advantage over standard dust collectors. Coupled with its unique design and its ability to be configured multiple ways, it is the ideal dust collection solution. Whether it is using it as a pre-filter for an existing system or replacing a faulty dust collector in a plant, the SplitStream will reduce maintenance, increase efficiencies, and improve the overall process.


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.

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Topics: pre-filter cyclone, GPC Cyclone, dust collection system efficiency, standard dust

Top 5 Reasons to Use a Cyclone Before a Baghouse or Cartridge Collector | Aerodyne

Posted by Tom Hobson on Apr 20, 2022 1:30:00 PM

Most industrial dust collection systems use a baghouse or a cartridge collector. Whether your baghouse or cartridge collector is 50 CFM or 100,000 CFM, there are advantages to putting a cyclone before the baghouse or cartridge collector. Here are 5 advantages to utilizing a cyclone in a dust collection system.

  1. Increased Removal Efficiencies

Cyclones will increase your total dust collection efficiency when added before an existing baghouse. Cyclones remove the larger, coarser dust before the particulate reaches the baghouse. This helps to lighten the load on filters, which results in less dust in the airstream and overall higher removal efficiency for the whole system.

  1. Longer Filter Life

Baghouses and cartridge collectors require compressed air to knock off the dust. The use of the compressed air forces the bag to expand around its cages during high pressure bursts. The constant expansion of the bag causes it to wear out at a faster rate. Putting a cyclone ahead of the baghouse will remove most of the larger dust from the baghouse, thereby minimizing the amount of dust coming into the baghouse or cartridge collector.

  1. Recovery of Product

If the dust being collected is valuable (such as gold or silver) or needs to be/can be reused, simply using a baghouse or cartridge collector will cause the material to get lost on the filters. A cyclone doesn’t require any filters and all the recovered material will eventually be removed through the dust discharge valve.

  1. Easy Maintenance

Baghouses and cartridge collectors are extremely high maintenance. They require confined space entry to remove and replace the bags. Furthermore, bag replacement can be a time consuming process. Cyclones, however, require very little maintenance. At most, plant engineers have to observe the pressure drop every so often, and inspect the walls of the cyclone to insure that is has not worn down from the application.

  1. Allows Baghouses to Operate in Difficult Applications

Bags and cartridges are not well suited for fibrous, sticky, or hydroscopic dust. Cyclones perform in these applications and prevent the material from reaching the filters. Placing a cyclone in front of a baghouse or cartridge will help prevent time and money spent on repairing or replacing the filter, and ultimately will lengthen the life of the filter.


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.

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Topics: pre-filter cyclone, GPC Cyclone, dust collection system efficiency

Top 5 Questions to Ask When Choosing a Material Handling Valve | Aerodyne

Posted by Tom Hobson on Mar 22, 2022 4:15:00 PM

Material handling valves come in all shapes, sizes, varieties, and with hundreds of available options. From rotary valves and knife gate valves to double dump valves and trickle valves the choices are nearly endless. With such a vast selection available, choosing the right material handling valve for a given application can be a difficult task and choosing the wrong valve can be costly.

While there may be more than one possible solution to a material handling need, there is often a best solution to be found if the proper considerations are given. Here are the top five questions any plant manager or plant engineer should ask when choosing a material handling valve.

  1. What is the nature of the material being handled?

The most important consideration for any material handling application is of course the material itself. The characteristics of the material being handled will determine what type of valve should be selected. Extremely fine material typically requires a valve with tight tolerances and seals to avoid material from dusting out to the atmosphere. Coarse or chunky materials often require a valve with larger clearances to avoid plugging or jamming of the valve mechanism.

  1. Will the valve meet your operational parameters?

Not all valves are created equally and the environments they are expected to operate in vary as well. In many cases material handling valves are put to use on systems with some degree of atmospheric pressure differential. Most material handling valves are intended to be airlocks as well; allowing solid material to pass through the system without allowing major pressure losses. Be sure to select a material handling valve that has a pressure rating within the range it will be expected to operate.

  1. How should the valve be powered?

All too often, plant maintenance personnel accept the “standard” valve control type listed by the manufacturer rather than choosing the best actuation method for the job. Pneumatic cylinders are the most widely used actuators for knife gate valves and many other process valves due to their continuous-duty rating and readily available shop air supplies. While pneumatic controls may appear to be an easy and convenient method to operate a knife gate valve, a manually operated unit may be more suitable and cost-effective for maintenance valves which are operated very infrequently.

  1. How easy is it to maintain?

Regular maintenance is a must for any material handling valve. As valve parts wear or material build-up occurs, the need for replacement, repair, and cleaning of the valve is inevitable. When choosing a material handling valve, close attention should be paid to how easily the valve will be to maintain. Quick-release access panels, change-in-place parts, and easily accessed wear parts all make the job of performing regular service on a valve much easier.

  1. How much will it cost?

While the initial investment for a material handling valve is important, it is only part of the equation. Frequent repairs or labor-intensive repairs to a valve can easily eat into any initial savings in cost. The cost of process downtime due to maintenance needs can become magnified if the valve cannot be repaired in place or replacement parts are not readily available.

Doing the proper due diligence also goes a long way in selecting the best material handling valve for a given application. Realistically, the success of a material handling valve comes down to the careful consideration of application parameters and how much time and effort is given to make sure the appropriate valve is selected.


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.

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Topics: material handling valves, double dump valve, airlocks valve

Wet Scrubbers Allow for Easier Collection and Removal of Certain Materials | Aerodyne

Posted by Tom Hobson on Feb 28, 2022 9:19:11 AM

Wet scrubbers are used in dust collection for a variety of reasons. One of the main reasons is allowing for easier collection and removal of certain materials.

What is the Relationship Between Water and Particulate?

Certain materials can be easier to collect and dispose of when captured by a wet scrubber. Wet scrubbers work by using water droplets to make contact with the particulate. The water can encapsulate or attach to the small particulate and this combined pairing has a larger diameter and sometimes heavier density to help in the dust collection. In general, the heavier and larger the size of particulate, the greater the removal efficiency will be. This is also true for mechanical dust collectors such as cyclones. 

Also, some particulate is easier to collect when wet rather than dry. Water can help wash material off the walls, preventing buildup on the walls or critical spots in the system. Some particulates are water soluble and will easily drain out of the system as a solution or in a slurry.

What is the Drawback of Water?

However, water can also create a mess for some material. Some material absorbs water and can become sticky. Others can react with the water and coat the system thereby causing issues. Abrasive material (such as sand) can wear away at walls as the water flow through the system, thereby increasing the amount of erosion. Wet scrubbers also create a water waste stream that must be treated whether in a plant or municipal water treatment facility. Solids that don’t dissolve must be separated and the dissolved solids must be precipitated out unless the waste stream can be recycled into a process. 

So when it is time to decide if a wet scrubber is suitable for your application, understand how your particulates will handle heavy humidity and wet environments. The problems caused by water could outweigh the benefits provided by using a wet system.


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.

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Topics: dust collector, Wet Scrubbers, Water and Particulate

Wet Scrubbers Can Help Prevent Some Fires and Explosions | Aerodyne

Posted by Tom Hobson on Jan 28, 2022 10:45:00 AM

Wet scrubbers are used in dust collection for a variety of reasons. One of the reasons is to help prevent fires and explosions.

Wetting Particles Using Wet Scrubber

Since wet scrubbers use water to help with dust removal their environments usually have a very high humidity. In this environment dust particles become wet and this can often prevent them from catching fire and/or exploding. Material such as wood has a much different fire danger when it is wet compared to dry.

As we see on the news, when there is a draught there are more forest fires around the country. This also applies to wet scrubbers. Spraying water on a solid can often prevent an explosion or fire. This is done by wetting the particles thereby making it harder for them to combust but also by wetting down any spark or fire that could cause an explosion.

Material Used vs. Wet Scrubber

If you are using a wet scrubber there are some thing you should keep in mind. Some material, such as alkali metals, will react with water and potentially explode. Other metals like magnesium can also cause fires and explode with water. Keep in mind that controls need to monitor the water in the wet scrubber system, because if it loses water, an explosive situation could quickly develop. 

So when looking at an explosive application, wet scrubbing can often provide dust removal for you, but not always. There are certain disadvantages of wet scrubbing that should be reviewed before determining if it is the right solution for you.


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.

Free Consultation

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Topics: dust collector, wet scrubber, explosive dust

Air Leakage in Airlocks | Aerodyne

Posted by Tom Hobson on Dec 17, 2021 11:00:13 AM

Airlocks are required in order for dust collectors to operate correctly. When a dust collector is under positive pressure, the airlock prevents air and collected material from blowing out of the dust discharge flange. A lack of airlock will cause dust to be thrown into surrounding areas and pile up on the floor and other surfaces.

When a dust collector is under vacuum, an airlock prevents air from entering the dust collector from the dust discharge flange. If no airlock is installed, air will leak in through the dust discharge, re-entraining material from the hopper while lowering the airflow at the pickup points.

Which Type of Airlock You might Use

Every airlock will leak a certain amount of air into or out of the hopper depending on the conditions the hopper is under. Depending on your application, the amount of acceptable leakage might determine the type of airlock you use.

A knife gate has the greatest amount of leakage, because when the knife gate is open, there is no airlock, only when you close the knife gate will you achieve an airlock.

A rotary valve provides a good, steady airlock but in order for the rotor to turn, there must be a gap between the rotor and the housing. This gap allows air to constantly leak past the rotor. The rotary valve also will allow air pass if the pockets in the rotor are not fully filled with material.

The double dump valve provides one of the lowest leakage rates of an airlock. The double dump valve is similar to having two (2) knife gates in series. This creates a chamber between the two flap plates. At all times one of the flap plates is closed, so the total leakage in the double dump valve is the volume of the chamber minus the volume of the material in the chamber.

Aerodyne’s Vacu-Valve

Aerodyne also produces a Vacu-Valve, which provides low leakage. The Vacu-Valve can only be used on applications with a slight vacuum and must have material that is fine and free-flowing (doesn’t easily bridge). The Vacu-Valve has an opening that a rubber sleeve is attached to. This sleeve is pulled together by the vacuum in the hopper.

Material then begins to build up above the sleeve. As the material builds up, gravity and the weight of the material slowly trickles the material down through the sleeve and out of the system. This trickle action is dependent on many conditions, including the weight of the material, the amount of vacuum in the system, and the ease of the particles to flow through the sleeve (particle size, stickiness, etc.)

So when selecting an airlock for you dust collector, don’t forget to factor in the air leakage each airlock will allow.


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.

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Topics: knife gate valve, vacu-valve, airlocks valve

Aerodyne Environmental: Home of the Horizontal Cyclone and  Vacu-Valve® Airlock Valve

Inspired To Be Different.

At Aerodyne, we choose to take a different approach to collecting dust and handling materials. Our cyclones are unique in design to address common issues such as problematic dusts and space constraints. Our airlocks are chosen to fit your specific application instead of hastily installing traditional equipment options. We believe that when we see things differently, we can solve problems effectively. That's why so many people turn to us for help in solving their tough dust problems.

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