Triboelectric vs. Optical Bag Leak Detectors - Finding Leaks in Minutes Instead of Days

Posted by Earl Parker on Feb 29, 2016 10:30:00 AM

When dust collector filters begin leaking operators must act quickly to remedy the problem. Even just one leaking baghouse filter can be enough for an entire system to exceed its emissions limits for PM 2.5. Additionally, the longer leaking filters remain in use the worse the leak becomes, potentially creating large amounts of dust accumulations in the collector and areas near the exhaust. 

For this reason, many facilities have decided to supplement traditional optical detection with a triboelectric bag leak detection system into their process. Additionally, many industries now fall under MACT (Maximum Achievable Control Technology) standards from the EPA. Many of these MACT standards include provisions requiring the use of bag leak detection systems for all dust collectors used in certain applications.  

Opacity-Emissions-Example.jpgA Choice Regarding Dust Collector Emission Monitoring

After considering the facts many plants have decided to invest in better detection and monitoring systems for their dust collectors. However, what options are available? 

Essentially, there are two main types of dust monitoring technology in the market today, optical detectors (that indirectly measure particulate emissions by monitoring opacity) and triboelectric detectors (that measure particle emissions by monitoring the triboelectric effect). Though as they relate to dust collectors and bag leak detection the two technologies are not equal. 

Triboelectric Detectors Have Superior Leak Detection Capabilities

Due to the sensory limits of optical systems, many are not able detect leaks until the emissions levels have risen to above 10% opacity, a level that corresponds to total particulate emissions levels above nearly all air permits in operation today. In short, opacity meters can only alert once the source has already exceeded its limits. In addition,  the secondary aspect of this lack of sensitivity relates to the inadequacy of optical devices to quickly identify filter leaks when they arise. 

The bottom line is important too. In this regard optical detectors, which are less sensitive, are typically much more expensive.

Case Study Highlights Shortcomings of Optical Leak Detection Systems

The recorded case study of an aluminum reduction facility highlights the deficiencies of optical based leak detection systems compared to triboelectric based systems. The facility arranged a trial of both systems in order to determine which technology would more quickly locate leaks, help pinpoint leaks and to test reliability.

Once both systems were operational a controlled test was conducted whereby a small 1/4” hole was made in one of the 3,600 filters in the plant’s shaker baghouse system. The Auburn triboelectric bag leak detector was able to detect the minute amount of dust coming through the 1/4” hole the first cleaning cycle, and the Tribo.trac Leak Locator was able to isolate the location of the leak to a specific compartment ten. With a minimum detection range of 0.005 mg/m3, the Auburn bag leak detector was able to detect the leak well in advance of visible emissions, minimizing cleanup time. In contrast, the optical system did not detect the leak for over 2 days, by which time the tear had increased from 1/4” to nearly 8” long. In that time, over 60 cubic feet of dust had accumulated in the compartment, requiring over 10 man hours to clean, compared to the 2.6 cu ft of dust accumulated with the Auburn system.

Typically in this sort of situation adjacent, and then nearby, bags are damaged by the dust which leads to potential contributing failures and additional repair costs.

Real World Test Results

   
  Triboelectric System Optical System
Estimated Time to:    
Detect Leak Less Than 1 Hour 2 Days
Locate Leak Less Than 1 Minute 2-3 Man-Hours
Clean Up Leak Less Than 1 Man-Hour 8-10 Man Hours
Estimated Size of:    
Hole Detected 1/4" 8"
Dust Cleaned Up 2.6 cu ft 60 cu ft
Clean Up Tool Shop Vac Shovels

Turn Days Into Minutes with Triboelectric Leak Detectors

By switching to triboelectric leak detection systems the above mentioned aluminum facility now has significantly reduced the amount of time its personnel have to hunt for leaking filters. It also has reduced the frequency of overages and reportable events due to quicker leak detection. None of this would be possibly using optical detection methods currently available. 

As the above case study demonstrates, the advantages of triboelectric technology over opacity based systems make a compelling case for their adoption at your facility. Let Auburn Systems explain how their technology can improve your facility’s operation while also cutting costs. Click here to learn more about our free consultation. 

cement plant case study

Topics: Baghouse Maintenance, Bag Leak Detection, Dust Detection