Essential Guide To Combustible Dust Mitigation

This Blog provides a useful guide to reducing the risk of dangers associated with Combustible Dust in many types of manufacturing environments.

One of the most hazardous forms of industrial dust produced during the manufacturing and production procedures is combustible dust, which comprises particles that measure less than 420 microns and can ignite and explode when suspended in the air. Combustible dust is detrimental to both the environment and the workers who come into contact with it.

To ensure the safety of employees, maintain smooth production, and comply with safety and air pollution regulations, industry experts at Airtight Solutions engineer uniquely tailored dust collection solutions and provide aftercare service solutions to mitigate dust-related hazards.

Combustible Dust Safety Measures for Operations and Personnel

Industrial manufacturers can protect their operation to run smoothly and keep employees safe from combustible dust explosions by utilising safety and anti-explosion systems, adhering to a range of safety protocols, and wearing suitable personal protective equipment (PPE). Strategies and procedures include, but are not limited to:

• The implementation of exclusion zones, which limit entry to specific regions within industrial facilities to minimize the risks to workers and equipment in the event of an explosion. These zones are typically established around hazardous areas such as those containing high voltage equipment, heavy machinery, and/or other hazardous materials.
• Conducting regular workplace inspections to identify areas where combustible dust may accumulate.
• Regularly cleaning surfaces and equipment and using specialized equipment designed to repel dust.
• Using proper ventilation systems to control, collect and dispose of dust.
• Using appropriate personal protective equipment (PPE) including masks, eye protection, and protective clothing.
• Implementing safe work practices by avoiding dust-generating activities, if possible, and grounding mechanised equipment to prevent sparks.
• Using explosion-proof equipment whenever possible.
• Providing regular combustible dust training and safe work practices training.  
• Using the right explosion venting strategy.

Common Explosion Venting Strategies

One of the most effective measures for mitigating hazards stemming from explosions caused by combustible dust is the implementation of the right explosion venting strategy. There are various approaches to explosion venting, and the right solution will depend on several considerations. Explosion venting strategies include:

Isolation: Isolation prevents dust from having a chance to accumulate in the first place. Equipment or processes that generate dust can be enclosed, and dust collection systems can be used to prevent the dust from migrating to other areas.

Venting Panels: Venting panels are designed to open and relieve the pressure generated during an explosion. Venting panels can be installed in walls, roofs, or attached to equipment, and are built from temperate & blast proof materials.

Explosion Suppression Systems: These systems rapidly detect and suppress an explosion through the aid of various suppression agents, such as chemical powders, water, or dry chemicals.

Deflagration Venting: This approach involves specifically designed ventilation systems that allow the pressure generated by an explosion to be released in a controlled manner through the use of vents or ducts.

Dust Explosion isolation valves: Typically installed on ducts or conveyors they are triggered by the pressure generated by an explosion. Once triggered, they isolate the equipment where the explosion occurs, preventing it from spreading to other areas.

Flameless Venting: Diverts or suppresses explosive gasses that are produced during industrial processes. While traditional venting systems use controlled flames to burn off these gasses, flameless venting systems use special materials and designs to collect, cool and diffuse them before they can ignite. 

Flameless venting solutions are often used when traditional venting systems may not be possible or used safely – for example, in enclosed spaces or areas with high employee foot traffic. 

Preventative Maintenance

Preventive maintenance is a critical component of managing the risks associated with combustible dust. Proactive maintenance can help identify potential problems and resolve issues before they escalate into a serious risk. An on-going maintenance plan may include:

• Regular cleaning as part of a comprehensive preventative maintenance program that can help reduce accumulated dust.
• Properly lubricating equipment that can reduce friction and prevent sparks from developing. 
• Ensuring all wearables (valves, filters, diaphragms) are in proper working condition.
• Replace damaged or worn-out door seals and gaskets.
• Inspect the dust level of your system’s hopper regularly as they are not designed to hold material.

Wet Scrubbers & ESP’s

In addition to improved ventilation, preventative maintenance, and explosion venting strategies, wet scrubbers and electrostatic precipitators (ESPs) are two air pollution control devices that can help alleviate combustible dust.

Wet scrubbers work by introducing a liquid, often water, into a gas or air stream, which captures and removes potentially flammable particulate matter. The dirty liquid and the captured dust are then treated and disposed of separately. Wet scrubbers are often used in industrial settings such as power plants, chemical plants and metal processing facilities. Overall, they are an effective air pollution control device because they can remove a wide range of pollutants and are highly customisable. If considering a wet scrubber, it is important to note that they require a source of clean water, and that the liquid and captured pollutants must be managed carefully so as not to contaminate other water resources.

Electrostatic precipitators or ESPs work by using an electrical charge to attract and capture dust particles in the air. As gas or air streams pass through the device, particulate matter becomes charged and is attracted to collection plates with the opposite charge. The captured dust is then removed from the plates and safely disposed of. Like wet scrubbers, ESPs are often used in power & chemical plants, with other industrial applications including cement plants and commercial cooking exhaust systems. ESP systems are highly efficient in capturing fine and ultrafine particles, including those not easily captured by other air pollution control systems. If considering an ESP device, it is important to note that they require regular maintenance and cleaning to ensure effective performance.

High-Risk Industries Unaware of Combustible Dust Risks

There are several industries where combustible dust poses a significant risk, but its presence is not well-understood. This lack of awareness can lead to a higher risk of explosions and fire, so all customers are encouraged to speak with a professional about their air pollution control needs. These industries include but are not limited to:

• Education – Schools, TAFE & Universities: Woodworking, which involves the cutting, sanding and shaping of organic wood materials can produce large amounts of fine, highly flammable dust. Companies like Airtight offer combustible dust collectors specifically designed for school environments.  
• Food & Beverage Processing: Organic materials like flour, sugar, spices and grains can produce highly combustible dust when handled, transported or processed.
• Pharmaceutical Manufacturing: Many drugs and medicines are made from organic materials which can generate combustible dust, creating a potential risk for explosions if not properly controlled.
• Chemical Manufacturing: Many chemicals are considered to be highly flammable and explosive, and their handling can generate combustible dust that can be ignited by sparks or other sources of ignition.
• Recycling: The processing of paper, plastics and metals with high-speeding sorting & crushing equipment can produce significant amounts of combustible dust.

The Best Solutions for Combustible Dust Requirements

Airtight helps customers understand and tackle combustible dust problems through a hierarchy of controls. In this methodology, the most effective control is to eliminate the problem altogether. Customers are encouraged to substitute combustible materials with non-combustible ones whenever possible. If this is not possible, Airtight engineers isolate and address the problem mechanically by uniquely tailoring a variety of dust control and disposal systems and preventative maintenance & servicing packages to the specific needs of the customer. 

Summary

Airtight Solutions engineers a vast range of combustible dust mitigation solutions. For assistance or questions about combustible dust issues, please feel free to reach out to one of our experienced team members at 1 800 424 784 or visit airtight.com.au.