Fire Prevention Tips for Wood Pellet Plants
My last blog discussed the dangers of wood pellet plant facilities and included an overview of several recent incidents. Today, I would like to review a few fire prevention tips for wood pellet plants. The process of manufacturing wood pellets involves all the right ingredients for explosions and fires to occur with a concerning frequency the potential to cause serious injuries, damage to property, and interruption of production.
The amount of wood, dust, various ignition sources inherent in the wood pellet production process presents a high risk of explosion and fire. However, there are strategies that can be implemented to reduce the risk of fire and explosions and to mitigate the impact should they occur:
- Conduct a Risk Assessment – professionals, like fire protection engineers, are well-versed at identifying risks for various facility types. A risk assessment will include a physical survey of the facility or designated area to identify and quantify various explosion and fire threats to life, property, and business operations. The assessment will identify and quantify various defenses against those threats. The results of the assessment will be carefully analyzed and any significant weaknesses in the explosion and fire defenses will be identified. Specific solutions to correct these weaknesses are then developed and are optimized for cost and function. The building owners, tenant, and stakeholders should be involved in the process of optimizing solutions so that their specific objectives are understood and satisfied.
- Combustible Dust Considerations – many times, incidents at wood pellet production facilities involve combustible dust, as seen in the examples described above. A few strategies to help mitigate combustible dust exposure include:
- Process equipment that contains combustible materials, including combustible dust, should be shut-down, and cleaned of all combustible materials before performing any maintenance activity;
- Applying water to a fire within enclosed equipment that contains combustible fines and powders is inherently dangerous and should be avoided because the water application can disturb combustible powders and rouse them into a flammable dust cloud, which can result in a flash fire or explosion;
- Generally it is safer to shut down the equipment and use firefighting equipment to protect the exposures, allowing the fire inside the equipment to burn itself out; and
- Any factory that handles, processes, or produces combustible dusts—and especially a factory with this reported history of combustible dust incidents—would be well-advised to retain the services of a qualified expert to regularly audit the plant for combustible dust fire and explosion hazards and provide recommendations for mitigating those hazards in accordance with applicable NFPA combustible dust standards. The expert should also be retained to provide general awareness training on combustible dust explosion risks to the plant’s management, operations, and maintenance personnel.
- Overall Construction Standards – According to Rob Cruickshank of the RSA Group, “using non-combustible construction materials and composite panel insulation are first choices when it comes to wood and biomass pellet production plants.” He further advises that composite panels should have a minimum fire resistance of two hours, and be made with mineral wool rather than expanded foam plastic insulation. Walls separating fuel storage facilities from the rest of the plant should be concrete and provide at least two hours of fire separation.
As the wood pellet production industry continues to grow, so does the importance to facility owners of developing strategies to minimize the exposure to fire and explosion risks. Steps should be taken to design explosion and fire safety into these facilities, as well as implementing safe operation and effective maintenance processes. An experienced fire protection engineer with credentials in combustible dust risks is a great partner to help you develop the appropriate explosion and fire protection design and prevention strategies needed to help mitigate the exposure of your employees, facilities, and the surrounding communities to these risks.
By Jeff Harrington, CEO and Founder of Harrington Group, Inc.