Bag Leak Detection Blog

Planning Ahead to Minimize Downtime

Many industrial facilities work hard to plan scheduled downtime to conduct maintenance as needed throughout the year. In some, however, production and operational requirements preclude periodic shutdowns. And for others, shutting down the process, even partially is not practical due to the amount of time required to restart production. For these reasons many facilities plan yearly maintenance outages where major repairs, installations and other tasks can be done all at once.

Following a comprehensive PM plan throughout the year is an effective way to minimize downtime. Planning is the key to efficient shutdown maintenance that accomplishes all required goals and helps reduce unplanned downtime during the rest of the year. Plants with dust collection systems preparing for their yearly shutdowns can begin planning for the following tasks now to achieve the best results come shutdown time. 

Annual Preventative Dust Collector Maintenance Inspections

What happens when the trackers aren't tracking?

Problems within pneumatic conveying systems can quickly cascade into large production issues for facilities. These can cause disruptions to batch products, overflows can create cross contamination between products or processes, and blockages can damage equipment or create safety hazards including combustible dust hazards. So it's understandable that fill level indicators are carefully monitored on bins or hoppers in manufacturing processes. 

However, what can be done if these indicators malfunction for some reason? Having a fail safe or backup monitoring source for these systems has proven a wise investment for many facilities. 

Using Triboelectric Flow Monitors As Backup Monitoring

Taking the Good with the Bad

Pneumatic conveying systems are the best solution for many bulk product handling requirements. They have a number of advantages, but also some associated drawbacks. Product damage, blockages and maintenance are widely recognized challenges. Less frequently discussed, but perhaps just as costly is the energy requirement to push or draw the volume of air/gas through the system to move product.

Direct costs from fans, blowers and compressors for pneumatic conveying systems can be substantial. However, new technologies allow companies to precisely measure particle velocity, and to dynamically adjust fan/air speed accordingly. This reduces energy wasted on excessive conveying speed (which is dissipated as heat and results in damage) and eliminates the need for manual adjustments.

Pneumatic Conveying - Flying Blind in Strong Headwinds

Differential Pressure - Not necessarily the best parameter for dust collector/baghouse monitoring

DP is the king of dust collector monitoring metrics. However, some users have come to think that it is the ONLY metric to monitor on an industrial dust collector. This certainly is not the case…especially as the size and complexity of the system increases. Here are 4 important areas for which differential pressure cannot provide adequate insight.  

Total Emissions Levels

Differential Pressure is a Critical Baghouse Performance Metric

Successfully operating your dust collector means carefully monitoring the differential pressure on each unit. Differential pressure is the principal operating metric used to monitor performance of a dust collector. 

Most modern collectors operate at peak collection efficiency between 2” - 6” of differential pressure. For this reason, many air permits (as well as operating documentation) specify a DP range for the collector "not to exceed" in order to achieve emissions compliance. This is combined with other performance considerations, such as rising or falling airflow throughout the system, to provide an operating view that is monitored in parallel with the emissions output readings. 

What to Do When DP is too High or too Low?

Let's Get Real About MACT

Ask any environmental compliance engineer what their biggest worry is and they will likely mention something involving MACT (maximum achievable control technology) standards. As MACT standards come to cover more and more industries, many facilities have found achieving compliance to be a significant challenge. Frequently they find that under investment in air pollution control over a number of years substantially complicates their compliance. Some have held out for political change that they assumed would lead to a revocation of these standards. Although the MACT program is firmly established by law and not subject to any executive directives or revision like some other standards, they've built programs of minimal compliance assuming that MACT would be reversed. It hasn't. It's exceedingly unlikely that it will. 

What Are MACT Standards? 

Real World Complications

When unloading bulk material, sudden changes in air flow can create complications for material conveying systems. Rapid increases in material flows, or high volume air flow as material flow suddenly slows, can damage filters within the system filter receiver. Often this change occurs quickly, and even if operators are diligently observing, they may not react quickly enough to prevent damage.

How can plants avoid these issues and prevent damaging their filters?   

Common Causes of Sudden Increases in Flow Rates

In most cases, there are several causes of sudden increased material flow. 

Pneumatic Conveying Convenience and Flaws

Many industries use pneumatic conveying as part of their manufacturing process. This includes many food processing and manufacturing plants as well. It's often used for the conveying of certain "dusty" food ingredients such as grains and sugar which pose certain well documented challenges including combustible dust hazards, sanitary or flow rate control. 

Just because...it's time

Many plants change their baghouse filters based on a firm schedule. Others prefer to wait until the filters begin to show signs of leaking and then they replace them. Others use differential pressure as a guide, replacing the filters once the DP begins to trend above a certain level. And others simply wait until a reportable event, citation from an air quality inspector or massive loss in system suction (process flow) before taking action. What is the best method for scheduling filter replacement? 

Best Reasonable Solution for Emissions Monitoring

Many plants continue to use EPA Method 9 visual observations as their primary dust collector monitoring methodology. Even as newer plants have already moved on to modern monitoring technologies, such as triboelectric dust monitoring, these plants continue to hold fast to their Method 9 CAM plans. Does triboelectric dust emissions monitoring really provide a realistic alternative to visual observation? In many cases, visual observations were the most accurate and feasible solution at the time the air permit was written. And many are still following this method today. But technology has advanced significantly and today visual observation is less reliable, less accurate and substantially more labor intensive compared to electronic instruments.