What does it cost to own your dust collector filters?

"When it comes to choosing filters for a cartridge dust collector, powder and bulk processors sometimes regard these items as more or less of a commodity. If Filter A and Filter B both offer the same rated efficiency and fill any special requirements – say, for example, the need for fire retardant media – then the lowest-priced filter would appear to be the better choice. In fact, the opposite may be true. But it requires a 'Total Cost of Ownership' (TCO) calculation to know for certain. Similar in concept to life-cycle costing, TCO is a very useful approach for deciding what filters to select for a dust collection application. TCO incorporates a step-by-step evaluation process encompassing three categories..." Read this full, informative article here.

FAQ: Our dust collection system handles a very fine dust and is having problems with dusting and emissions. What can I do to fix this problem?

The most obvious fix is to upgrade to a filtration media with higher efficiency. There are many good choices available, and a reputable filter supplier should be willing to guarantee in writing that the maximum emissions rate will fall below threshold limits established by OSHA or EPA for the dust in question.

Filtration efficiency is only part of the picture, however. Dust collector cartridges with open-pleated media tend to hold more dust between cleaning pulses and release the dust more readily during cleaning than filters with tightly-packed media. Most dusting and emissions problems occur during pulsing, so this difference in cartridge construction can make an impact. Also, a good electronic control system – programmed to provide “on demand” rather than continuous pulsing – will prevent over-cleaning of cartridges and reduce the chance for dusting to occur. As a side benefit, on-demand cleaning will save on compressed air and energy costs. For more information, read the article, Asking the Right Questions.

Dust Collectors for High Pressure Applications

For some processes, a dust collector with extraordinarily high suction is required. We're talking up to 17 inches Hg (Mercury)!  As you would expect, this type of unit is a heavily reinforced dust capture vessel. It is commonly used as a central vacuum system, positive or negative product receiver or high pressure bin vent in a many industries and processes.

Controlling emissions and filtration efficiencies don't have to be compromised with these types of units. Look for 99.99% (MERV 11) or 99.999% (MERV 15/16) on 0.5 micron particles. Cylindrical vessels with cyclonic tangential inlets knock out most of the dust as it enters, minimizing dust contact with the filters (which prolongs service life). Options can include explosion vents for combustible dust applications, bag-in/bag-out (BIBO) access door and continuous liner discharge for pharmaceutical or hazardous dust.

An installation photo of a high vacuum dust collection can be seen here. Additional, technical information can be found here.

Cartridge Dust Collectors Slash Emissions, Save Water and Energy for Major Mine

Controlling the high levels of dust generated in crushing operations to meet stringent permitting requirements is a difficult challenge for mining engineers. At one U.S. copper mine, the use of a cartridge-style dry dust collection system has reduced emissions to a level of only 0.00037 grains/dry standard cubic foot (dscf) average. This is just a fraction of the required limit of 0.02 grains/dscf – while delivering added benefits of energy savings, water savings and ease of maintenance.

Read the full case study that appeared in Technology News. A PDF file of the article can also be downloaded.

FAQ: What are the ATEX requirements for industrial dust collection?

ATEX is short for the French term ATompheres EXplosibles in the title of the 94/9/EC directive. ATEX is related to dust collection by providing guidelines for equipment and electrical components used in different levels of explosive environments. ATEX provides guidelines for end users or workplaces and equipment manufactures.

• ATEX 95 equipment directive 94/9/EC, Equipment and protective systems intended for use in potentially explosive atmospheres;
• ATEX 137 workplace directive 99/92/EC, Minimum requirements for improving the safety and health protection of workers potentially at risk from explosive atmospheres.

Employers must classify areas where hazardous explosive atmospheres may occur into zones. The classification given to a particular zone, and its size and location, depends on the likelihood of an explosive atmosphere occurring and its persistence if it does.

Areas classified into zones (0, 1, 2 for gas-vapor-mist and 20, 21, 22 for dust) must be protected from effective sources of ignition. Equipment and protective systems intended to be used in zoned areas must meet the requirements of the directive. Zone 0 and 20 require Category 1 marked equipment, zone 1 and 21 required Category 2 marked equipment and zone 2 and 22 required Category 3 marked equipment. Zone 0 and 20 are the zones with the highest risk of an explosive atmosphere being present.

This chart (click thumbnail image) will help relate the equipment category to the equipment area or zone. An instruction manual for an ATEX classified dust collector can be requested/downloaded here.

Dust Collectors and Sustainability

Are you green conscious? You don't have to compromise when faced with buying dust collection equipment for your factory. Ask about the environmental benefits of the dust collector you're considering. By definition, these systems are designed to stop thousands of different pollutants from entering the workspace air and the outside air. Well-built equipment that lasts will create less waste over time. Some high efficiency filters in the dust collector can last twice as long as others, which contributes to sustainability while saving energy. Even the paint used on a dust collector can be contribute to sustainability. The powder paint process is environmentally friendly, emitting no VOCs to atmosphere. Furthermore, premium efficiency fans provide optimum energy efficiency. For further information, download a PDF brochure on sustainability and dust collection here.

What are the biggest misconceptions manufacturers have relative to their OSHA responsibilities related to combustible dust?

The biggest misconception among manufacturers is that OSHA is just presenting them with a guideline, not with something they have to do. The fact is, OSHA is beefing up enforcement of safety measures on several fronts, and combustible dust has become one of the top priorities since the agency re-issued its National Emphasis Program (NEP) on this topic in March 2008.

Under the OSHA NEP, manufacturers are required to follow applicable NFPA standards including the revamped NFPA 68 Standard on Explosion Protection by Deflagration Venting, which provides mandatory requirements for dust collection applications involving explosive dusts. Sometimes other safety standards such as Factory Mutual may be applied instead, but these are no less stringent than NFPA and all are treated as legal code by nearly every town and county in the U.S.

For additional information, read the article, Five Ways New Explosion Venting Requirements For Dust Collectors Affect You. The article can be downloaded as a PDF.

Case Study: Powder Paint Process Requires Efficient Dust Collection

You may ask what the porpoise was in setting up Dolphins Coatings with this cartridge dust collector after their cyclone went up in flames. This company was in need of a complete filtration system that not only removed dirty air but also filtered the air before it was placed in the atmosphere. The challenges here were a lack of floor space and the air volume required by the booth manufacturer, which was 12,000 m³/h.

Click here to read the solution to this challenge. Oh, and sorry about the porpoise thing...

Upcoming Live Webcast on Dust Control

Here's an educational opportunity if you are faced with buying a dust collector or fume collection equipment for your factory. In this live webcast , on online panel of three experts will look at various issues and developments related to dust and dust collection systems.

Cartridge dust collection systems can meet multiple objectives in plants, but choosing the best equipment for a given dust control application involves research and attention to detail. The presentation by John Dauber, Camfil Farr APC’s North American Sales Manager, will review how to select a dust collector that will comply with safety and emissions regulations, solve problems in the plant, perform reliably, and deliver maximum return on investment (ROI).

This webcast is free and will be held at ChemicalProcessing.com on October 28, 2010. You can register here.

Using Premium Efficiency Motors with VFDs on Your Dust Collector

There's some confusion as to why premium efficiency motors can be used with variable frequency drives (VFDs) whereas standard efficiency motors cannot. Camfil Farr APC technical director explains:

"One of the largest players in calculating the life expectancy or efficiency of an electrical motor is in its ability to dissipate heat or not generate heat in the first place. On standard efficiency motors, energy is lost in producing heat while another portion of energy is spent on the fan required to cool the motor. If you are not familiar with a motor design, there is a fan on the end of the motor. It is an integral part of the motor and is located on the opposite end of the output shaft. When the motor turns to perform the work you needed it for in the first place, it also turns the fan so that cooler air is blown across the motor itself. So, some of the energy you supply the motor to operate is used to turn the fan and not translated to the output shaft.

Premium efficiency motors reduce the amount of lost energy going into heat rather than power by using different and higher quality parts. Some of these parts include: steel with better magnetic qualities, bigger diameter wire, and better bearings. Since less heat is generated, less energy is needed to cool the motor with a fan.

Variable Frequency Drives (VFD’s) are used to speed or slow the operation of the motor. VFD’s can be used on standard efficiency motors, however it is not recommended or is very limited since standard efficiency motors do not have the same ability as a premium efficiency motor in limiting or dissipating heat caused by operation. Using premium efficiency motors in conjunction with VFD’s allows a much wider range to operate the motor while maintaining the expected motor life."

Dust & Fume Collection for Solar Panel Fabrication

For silicon wafer plants, fine fumes from the furnaces and laser cutting process must be extracted to protect workers and machines from the super fine dust that they emit. With the cadmium glass process, much more attention is needed due to the toxic nature of cadmium. Containment features such as Bag-In Bag-Out (BIBO) filter access and dust discharge removal are recommened. Also recommended are HEPA secondary filters to meet very stringent EPA laws which are at or below 0.0004 grains per cu ft (1 mg/cu meter). Click here to view dust collector installations at solar panel fabrication facilities and learn more.

FAQ: What kind of dust collection problems can result from poor filter media selection?

The problems that can result from poor media selection are numerous, but some of the main ones include: failure to comply with emission standards, excess energy use, shortened filter life, and dust collector failure. A thorough site survey, coupled with dust testing performed by a qualified lab, can help determine the right media for a given application.

Also, explosion hazards and compliance with new NFPA standards and OSHA guidelines are of major concern when selecting media in combustible dust applications. Carbon-impregnated media filters are very effective because they are conductive, providing a “static drain” on the media that eliminates the chance of a spark or ignition source from buildup of static electricity in the media.

Case Study: Watch Maker Makes Time for Dust Collection Safety, Energy Savings

As a growing company in Malaysia, a watch manufacturer faced daunting health and safety challenges. One of the most concerning at Micro-Mechanics was the safety and well-being of the employees grinding and polishing their watch components. Buffing compounds, fibers released from the buffing wheel and minute metallic particles were being generated from seven workstations. Read the full case study here and learn how the resolution not only provided clean air for the employees to breathe, but also reduced this company's energy consumption.