Integrated solutions include monitoring, collection and control to help manage complex risks
Dust control is essential for safety, operational efficiency, product quality and regulatory compliance in the chemical process industries (CPI). Many of the materials handled in chemical facilities are combustible or hazardous, making uncontrolled dust a serious explosion and health risk. In addition, airborne particulate matter can compromise product integrity through contamination or degradation. For these reasons, a fully integrated dust-control solution, including modern monitoring solutions and state-of-the-art collection systems, is critical to maintaining a safe and efficient facility.
“Whether a facility processes pharmaceuticals, food additives or industrial chemicals, a well-designed dust-control system is key to protecting workers, ensuring regulatory compliance and maintaining consistent production outcomes,” says Rick Kreczmer, president of RoboVent Inc. (New Baltimore, Mich.; robovent.com). “However, dust control has to go beyond basic ventilation — it’s about managing complex risks across safety, compliance and product integrity.”
In addition, while combustible and toxic dusts remain the most concerning and most regulated dust hazards, there is a recent trend toward proactively addressing dusts that pose lower-level risks, as well, says Matthew Richardson, vice president at Hapman (Kalamazoo, Mich.; hapman.com). “This is because all dust, especially in high concentrations, poses a risk. Lungs are designed to process air, not fine dust particles,” he explains. “There are a large number of common materials that are more than a nuisance, but that don’t have strict requirements on control of their fugitive dusts.”
He points to silica as an example. “Silica is used across many industries, and has historically had minimal concern paid to controlling the dust,” he says. “For the past several years, proper attention to adverse health effects has led to improved expectations and willingness to apply dust containment and control methods when handling silica as fine particles.”
“As a result,” Richardson continues, “We’ve seen more interest in adopting features and technologies that provide major improvements. Improved sealing, air management and dust collection come at a premium prices, but we have fortunately seen recent trends where companies see the value, and demand dust mitigation and management.”
Proactive dust management
To practice proactive dust management, processors must first identify their site-specific challenges and then devise appropriate dust-management solutions to address them.
“The chemical processing industry faces complex dust-control challenges due to the use of diverse materials and multiple processes,” explains Samuele Oliva, product marketing manager, dust collector systems for Discrete Automation at Emerson (Charlottesville, Va.; emerson.com). “The most relevant aspects are the management of potentially toxic and combustible dusts that pose a serious health and safety hazard.
“Modern dust collection systems must be designed based on attentive identification of dust types and risks of fires and explosions. This is usually achieved by conducting a dust hazard analysis (DHA), which is a systematic process used to identify hazards associated with combustible dusts in a facility, to ensure compliance with the local safety standards,” explains Oliva.
Once this is accomplished and all dusts and associated risks are identified, operators can begin to address issues proactively.
“Everything begins by selecting the correct valves and electrical equipment according to the identified risks, in order to mitigate any risk of explosion or fire ignition. The second step is implementing best practices, including intensive data collection through sensors, predictive maintenance programs, adopting pressure-based pulsing logic, capturing dust at emission points, optimizing airflow and selecting the right filtration equipment,” Oliva says.
Eugenio Silva, product manager, Intelligent Automation for Discrete Automation at Emerson, adds, “Dust-control systems are increasingly adopting smart products and integrated solutions that significantly enhance their effectiveness and manage associated risks in chemical processing environments.”
He says intelligent automation solutions ensure the seamless integration of dust collector systems and their supporting components. These solutions optimize pulse performance during cleaning cycles across multiple filter lines by leveraging sophisticated adaptive-control algorithms and integrated PLC. This breakthrough in operational efficiency enables real-time data analysis, providing high situational awareness and responsive management of dust control systems while reducing compressed air usage.
“The benefits of smart technologies are manifold,” says Silva. “Enhanced visibility into system performance gives technical teams greater control and confidence, enabling them to respond swiftly to potential issues by identifying early indicators. Additionally, it effectively mitigates excessive dust from reaching downstream equipment, such as blowers and vacuum pumps, protecting assets and reducing maintenance costs.”
To meet the challenges of dust collection and control in the CPI, Emerson launched a complete Dust Collector Monitoring and Control solution (Figure 1) that combines mechanical products with advanced automation elements, such as pressure and particle concentration sensors, basic sequencer controllers, Aventics airflow sensors, Movicon HMI/SCADA visualization interfaces and PACSystems PLC, I/O and edge analytics.
FIGURE 1. Emerson’s dust collector monitoring and control solution combines mechanical products with advanced automation elements
“As industry continues to evolve, integrating intelligent dust-control solutions is a transformative step that provides chemical processing operations with the technical platforms they need to ensure safety, compliance and operational excellence,” says Silva.
Robovent’s Kreczmer agrees that the emergence of intelligent, connected systems, such as the SAVE system from Robovent acquisition Nederman, are an important development in the battle to control dust. “SAVE is a smart monitoring and control platform that transforms a traditional dust-collection system into a responsive, demand-driven solution. Instead of running the system at full speed 24/7, SAVE uses sensors and airflow control to dynamically adjust airflow to different production lines or processes based on actual process needs.”
This helps to increase energy efficiency and improves safety and compliance. “SAVE continuously monitors system performance, filter loading, airflow balance and pressure drops across the system,” Kreczmer says. “That enables proactive maintenance and ensures that capture points are operating effectively.”
In addition, in multi-zone or multi-product facilities, the technology enables smarter airflow zoning and control. “This is especially valuable in CPI environments where dust types and process risks vary across the plant,” says Kreczmer.
Dust control challenges
Proactive dust control includes identifying site-specific challenges and dealing with them accordingly. Experts offer solutions for some of the most common dust challenges in the CPI, including toxic and combustible dusts, process and material handling dusts and fugitive dusts.
Toxic and combustible dusts. The key challenges associated with dust control for the chemical industry are related to the toxic or combustible nature of some dusts and the potentially harmful impacts they can have on the health and safety of the workforce. Fortunately, there are solutions.
“Toxic dusts are special cases and must be considered separately,” says Sven Troetsch, head of process technology, material handling, polymer division, with Coperion GmbH (Weingarten, Germany; coperion.com). “With toxic dusts, systems are often requested in negative pressure to minimize possible emission points as systems are never 100% leak-free. The filters used here must be very high HEPA [high-efficiency particulate air] quality,” says Troetsch.
“And combustible dusts, or critical dust concentrations in the air, must always be considered,” Troetsch explains. “Typical areas of concern are silos and cleaned filter systems. If precautions need to be taken here, systems such as explosion panels and quick-closing valves, among others, must be used.”
But determining what equipment is needed for toxic and combustible dusts can be challenging, according to the experts.
“Understanding the control measures required to effectively extract and safely filter these dusts from the work environment is complex,” says Richard Jones, sales manager, U.K. and Ireland, with Donaldson Industrial Solutions (Bloomington, Minn.; donaldson.com). “Toxic dusts need to be extracted and contained at every stage of the process using solutions such as ‘bag-in-bag-out’ for filter changes and continuous liners for dust collector bin changes,” he explains. “High-efficiency primary filters, paired with the appropriate grade of HEPA filter acting as a secondary ‘police’ filter, are essential to ensure that only clean air is released from the dust-collection process, helping to prevent risk of cross-contamination.”
And, facilities where combustible dust exists must perform country-specific risk assessments to identify where combustible dusts exist and assess the risk of fire or explosion at each point in the process, he says.
“Combustible dusts need to be tested to understand their explosive properties,” explains Donaldson’s Jones. “Once this data is available, the appropriate dust collector specification can be understood to comply with all the regulatory standards and directives, which vary on a country-by-country basis.”
For example, in Europe, these standards usually include workplace emission limits, environmental emission limits, machinery directives, ATEX directives, workplace safety regulations and dust collection/industrial ventilation system guidelines and regulations.
Once the dust has been determined to carry a hazardous, combustible or explosive risk, an appropriate collection and control solution should be selected.
The Donaldson Downflo Evolution (DFE) dust collector (Figure 2) range was specifically designed to handle the more complex requirements associated with the CPI. “The DFE is compact, robust and reliable with a range of sizes and options available to cater to a variety of dust control challenges found in this demanding environment,” says Jones. DFE collectors direct incoming air to an intelligent dropout zone for reduced filter loading and offer the MaxPulse Cleaning System, which delivers 27% more cleaning energy to filtration media compared to typical pulse jet cleaning systems.
FIGURE 2. Donaldson’s DFE dust collection system is compact, robust and reliable with a range of sizes and options
The collector was tested to determine if it could isolate a deflagration and stop flames or sparks from passing into the clean air plenum. When applied in conjunction with effective explosion protection strategies including inlet isolation and explosion venting, the performance results support conformance to Chapter 5 Performance-Based Design Option requirements of both NFPA 654 — to prevent the “extension of the flame front outside the compartment or equipment of origin except where intentionally vented to a safe location,” and to NFPA 69 — “to limit the risk of flame spread from vessel to vessel via interconnecting ducts.”
Process and material handling dusts. Most chemical processes generate process and material handling dusts. For example, many chemical processes, including blending, conveying and milling, generate dust, so source capture solutions must be tailored to each step to control exposure and reduce airborne contaminants from the start.
“Depending on the process and hazard level, this might include full or partial enclosure, custom-engineered hoods, fume arms for localized dust capture or dedicated capture points at material transfer or discharge locations,” says RoboVent’s Kreczmer. “In high-risk environments, a negative pressure-containment system or glovebox enclosure may be necessary to prevent release of hazardous compounds.”
One solution for process or material handling dusts is the growing adoption of retractable source capture hoods and modular cleanroom systems, as they provide a faster, more flexible and cost-effective alternative to traditional cleanrooms or permanently ducted dust-control systems. Kreczmer points to Duoair’s cleanroom enclosures (Figure 3), which are designed for safe handling of sensitive or hazardous chemical processes and offer a controlled environment that meets ISO 6-8 standards. “They are suitable for specialty chemical and pharmaceutical applications where air cleanliness and contamination control are critical and they offer faster setup and lower cost than traditional cleanroom construction.”
FIGURE 3. Duoair’s cleanroom enclosures are de-signed for safe handling of sensitive or hazardous chemical processes
Bulk solids handling is another well-known dust-collection challenge. Fortunately, equipment providers are devising systems to aid in controlling dusts generated during material handling. “In terms of bulk material transfer, dust collection systems need to be designed correctly with enough suction airflow to prevent fines from settling inside the piping or duct work, with sufficient filtration area and with proper filter cleaning to prevent dust buildup and increased pressure drop,” says Dominick Fortuna, president of Volkmann, Inc. (Bristol, Pa.; volkmannusa.com). “Volkmann vacuum conveyors have built-in filter modules, complete with reverse pressure cleaning. This technology is also applied in our bag and drum unloading stations for high efficiency throughout the process.”
In addition, chemical processors need to consider entry and exit points of materials into the various process steps. “Emptying bags and drums into a contained system can result in clouds of fine dust at the entry point, so it’s critical to have proper ventilation and suction into the dust collection system at these points,” continues Fortuna. “Dust spillage is also an issue, and it is up to operators, housekeeping and plant safety engineers to monitor these locations and promptly clean any spills. With Volkmann contained bag and drum unloading equipment (Figure 4), the proper ventilation and vacuum suction of airborne fines during emptying of bags and containers is built in, and the risk of spillage is minimized or eliminated.”
FIGURE 4. With Volkmann’s contained bag and drum unloading equipment, the proper ventilation and vacuum suction of airborne fines is built in and the risk of spillage is minimized
Matthew Richardson, from Hapman, adds that very effective technologies and methods have been available for bulk solids handling, but says there is interest in adopting features and technologies that provide major improvements.
“The types of technologies that are becoming more standard relate to integrated dust collection within equipment that recycles the material back into the process,” Richardson explains. “This technology minimizes investment, keeps materials where the process is already designed for them and provides significant savings by preventing product from becoming waste.”
Solutions from Hapman include hoods for bag dump stations and conveyors (Figure 5), integrated dust collection for bulk bag unloaders, along with dust collars and upgrades to standard flange sealing on all hoppers, notes Richardson.
FIGURE 5. Hapman hoods for bag dump stations and conveyors (shown here), integrated dust collection for bulk bag unloaders, along with dust collars and upgrades to standard flange sealing on all hoppers keep materials where the process is designed for them and prevent product from becoming waste
Fugitive dusts. While dust collection is the most widely recognized mitigation tool, it often leaves gaps when it comes to fugitive dust and airborne particle control, says Taylor Andrews, director of operations with SonicAire (Winston-Salem, N.C.; sonicaire.com).
“Dust collection systems are engineered to handle a specific process load and this works well if the process runs exactly as designed. But, in reality, operations shift,” says Andrews. “Downtime, variation, maintenance issues and process changes are inevitable. That’s why proactive housekeeping isn’t a backup plan, it’s a critical safeguard.
“We can’t expect the system to perform as intended when internal or external factors shift. Systems designed around theoretical conditions often fall short of the realities of the plant floor. Likewise, failing to keep equipment running smoothly leads to inefficiencies and increased risks,” Andrews continues.
“And, while we support the use of dust collectors to contain hazards, we understand that no system is 100% effective on its own. This is where SonicAire comes into the picture, we focus on fugitive dust, not collection, so we compliment traditional systems by filling in critical gaps.”
SonicAire’s engineered fan systems automate housekeeping and prevent overhead dust accumulation (Figure 6). They offer fans with two- and three-horsepower motors that can move dust other fan systems cannot. And, they provide fans for Class II Division 1 and Division 2 Hazardous Locations, as well as fans rated for high-temperature, high-humidity applications.
FIGURE 6. SonicAire’s engineered fan systems automate housekeeping and prevent overhead dust accumulation
“Dust control is about prevention, minimizing re-entrainment and redistribution during operations,” says Andrews. “Facilities can improve system performance by using these kinds of zone-specific airflow management and automated fan-control solutions. By actively managing airflow and proactively preventing dust from settling, they reduce the burden on collectors and improve long-term effectiveness.
“While there is no ‘silver bullet,’ a combination of thoughtful system design and disciplined preventive maintenance goes a long way,” Andrews continues. “This type of fully engineered dust-control solution, paired with the right collection system, is critical to a safe, healthy and efficient work environment.”
Joy LePree