As an occupational or environmental health and safety (EHS) leader, you manage risks related to employee safety in your workplace. These may include indoor air quality and/or emissions exhausted into the outside environment. You need to keep suspended particulates within allowable limits, and perhaps report compliance to agencies such as the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA).
These responsibilities give you a vested interest in the performance of the industrial dust and fume collector in your facility. This equipment is designed to draw in dirty indoor air through a network of hoods and ducts, filter out particulates, and exhaust filtered air.
Occupational Safety & Health Administration (OSHA) standards on ventilation 1926.57
“Ventilation shall be designed to prevent dispersion into the air of dusts, fumes, mists, vapors, and gases in concentrations causing harmful exposure. The air outlet from every dust separator, and the dusts, fumes, mists, vapors, or gases collected by an exhaust or ventilating system shall discharge to the outside atmosphere. Collecting systems which return air to work area may be used if concentrations which accumulate in the work area air do not result in harmful exposure to employees.”
Dust collectors are sturdy equipment that can operate for years with proper maintenance. But if a filtration system is overlooked, hidden problems can develop that back up dust into the air or escalate into collector downtime.
As an EHS officer, you need to know the equipment is operating effectively, and be alerted when it’s not. You also need to quickly gather current performance data, often differential pressure (DP) data, for mandatory reports. This makes dust collector monitoring an important issue.
IIoT Monitoring for Air Filtration
Until recently, monitoring a dust collector and gathering its performance data have been manual processes in most facilities. While larger plants may have an automated control network, these systems typically govern only core production equipment, leaving ancillary dust collection outside the digital oversight that EHS officers consider important. Typically, EHS managers have had to work with operations personnel to take manual readings from dust collection equipment gauges.
Now, with the advent of the industrial Internet of Things (IIoT), monitoring a dust collector can be automated and provide real-time information. The iCue™ connected filtration service from Donaldson provides continuous monitoring that is cost-effective, secure, and simple to install and use.
To implement the iCue™ service, a technician places a wireless cellular gateway with integrated sensors on the side of the dust collector. This gateway device communicates sensor data directly to a web-based application, without having to connect to the facility’s internal automation system. The system is easy to implement since it involves no IT integration.
As the dust collector operates, the iCue™ service monitors machine health automatically. If it detects that user-set alarm levels have been reached, an email or text alert can prompt timely attention. On a weekly basis, you also receive reports on machine status, providing insights into whether you’re operating within your permissible limits.
Relevant Indicators for EHS Purposes
There are typically three sets of dust collector data highly relevant to EHS professionals: differential pressure (DP), particulate trend monitoring, and relative airflow. The iCue™ connected filtration service can monitor all three, simply and accurately, with dedicated sensors. Here is why these three measurements matter:
1. Differential Pressure
Differential pressure (DP) is the difference between air pressure before and after the filters in a dust collector. A steady DP level is generally regarded as a meaningful indicator that the dust collector is functioning normally. Thus, DP is the most common indicator used on dust collectors today, and a metric that many compliance reports require to verify a facility is in compliance with its air permits.
Once an acceptable DP range is established, deviations may signal a problem within the collector. An increase in DP typically indicates that the filters are beginning to clog, and replacements may need to be scheduled. A rise in DP readings to a pre-determined level can prompt an immediate filter change. On the other hand, a rapid drop in DP can signal that the filters have become torn or damaged and are no longer providing adequate filtration.
Monitoring DP continuously can help avoid factory disruptions from compromised compliance by providing this visibility automatically. When differential pressure is over-laid with relative airflow (discussed below), EHS teams can watch the filters’ condition and detect when the fan is no longer able to maintain designed flow through the increasingly-loaded filters. At a given DP, the filters can be anticipated to reach their terminal loading and be changed proactively.
Real-time, Accurate Compliance Data
It can be an arduous process to manually collect dust collection data for reports. In many facilities, EHS managers rely on operations personnel to log data over a period of days or weeks. The data must be collected, and written notes transferred into a compliance report. The manual process and time lag make the information prone to error or even quickly outdated.
The iCue™ connected filtration service provides current, real-time information without having to go on-site or rely on other parties for data collection. Monitoring is continuous and the reports come directly to your laptop—especially helpful if you work off-site or supervise multiple facilities.
2. Particulate Trends
The second important indicator that can be monitored with the iCue™ service is particulate trends. A sensor can be placed in the exhaust vent of the dust collector to monitor changes in the concentration of particulates in suspended air.
Trouble with a dust collector isn’t always immediately evident. A small dust leak can sometimes escape notice from your maintenance staff for a period of time. Sensitive enough to catch even small changes, the particulate trends from the iCue™ service can provide more-reliable insight into whether your facility is staying within your desired regulatory limits.
A rising particulate trend can help indicate when a filter may have ripped or broken, or signal an air blockage that is interrupting dust collection. An alarm can then prompt maintenance actions that quickly restore the particulate concentration to an acceptable range.
It is important to note that the iCue™ service monitors deviations in particulate concentration once your facility has established a baseline. This baseline will be expressed as an absolute value, and determined through air quality testing, which requires specialized equipment and personnel separate from the iCue™ technology. Once you have invested in determining a desired baseline, however, the iCue™ service can give you visibility by alerting you to deviations, thus empowering you to act and maintain your chosen baseline.
3. Relative Airflow
The third important parameter the iCue™ service can continuously monitor is airflow. This is the volume of air in cubic feet per minute (cfm) drawn into the collector through its hoods and vents. A dust collector operates on the same principal as a household vacuum cleaner, requiring adequate suction strength to effectively pick up dirt from surfaces. The iCue™ service can help monitor the airflow trends with a sensor placed on the filter’s dirty side that reads static pressure coming into the dust collector.
In an industrial facility, both inadequate or excessive air flow into the dust collector can have consequences EHS professionals care about. Inadequate air flow may be unable to keep up with your process’s dust generation, causing a potential breach of your desired baseline limits. If the collector is unable to pull dust all the way through to the hopper, the dust can settle inside the ductwork or in the facility. This accumulation of dust can act as additional fuel in the event of a fire.
Excessive airflow may also increase fire risks. For example, sparks from your process can be pulled through the ducts to the dust collector, where dust can provide a fuel source. Other unintended consequences of excessive airflow include premature filter wear or even loss of valuable ingredients in your process.
Just as in particulate trend sensing, the iCue™ service provides a relative airflow reading. Once your facility has determined a designed airflow for your facility’s dust control needs, deviations greater than 10% up or down from the baseline may indicate a dust collector problem that needs addressing.
A Word About Dust Collector Management
These three indicators—differential pressure, particulate trends, and airflow trends—are of direct importance to EHS leaders for tracking and reporting. However, optimal dust collector management may also be a concern you share with colleagues in facility engineering and maintenance. For your common benefit, additional sensors are available to augment the iCue™ connected filtration service, specifically to monitor hopper plugs, bin level, compressed air feed, and humidity. Continuously monitoring these indicators can help flag problems early, help manage total cost of ownership for the dust collector and drive additional return on investment for the iCue™ service.
Use IIoT as an Ally
Factories invest in Industrial Hygiene and Dust Hazard Analysis work to set dust collection baselines and achieve their appropriate regulatory limits. Maintaining ongoing visibility to deviations from these baselines can minimize hazards and/or fines.
Industrial Internet of Things (IIoT) technology, like the iCue™ service, can be an ally in managing these efficiently. It can enable you to track key information automatically and share the information directly to the people that can respond and correct issues. As you manage the many potential risks in your organization, the iCue™ connected filtration service helps you with visibility and insights in an effective and efficient way.
