How Our Industrial Dust Collectors Work

The dust collection system works by infusing dust particles with water, and processing through a fixed-position, dual-opposed blade system. Once the dust-laden airstream and liquid are mixed, a tangential airstream is injected through the lower blade assembly to intensify turbulence.

Rotation is accelerated, droplets in the airstream are processed through a mist eliminator downstream, and particulate is deposited on the bottom of the unit for recovery or disposal.

Combustible Dusts and the Choice of a Dust Collector

Today, there is diminishing debate about whether dry collectors such as baghouses and cartridge devices, or wet dust collectors such as the Whirl/Wet are preferable when worker safety, facility protection and owner liability govern the decision-making.

A December, 2020 report published by the Fire Protection Research Foundation (Executive summary pdf available at www.nfpa.org) describes fires and explosions involving dry dust collectors in the US, Canada and China over a 10-year period. Among the study’s observations:

• Dust with sufficiently low minimum energy can easily be ignited by static electricity.
• Inadequate grounding or improper maintenance can lead to dry dust collector explosions.
• Friction-induced heating can cause dust temperatures to rise if there is sufficient accumulation. Two of the most disastrous fires involving dry dust collectors and described in the report were caused by friction heating.
• Spontaneous combustion (self-heating ignition) occurs in various industrial metals when they react with water. According to NFPA 654, Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids, most water-reactive products are powdered metals. Aluminum, magnesium, titanium, and others form oxides by reacting with water. The reaction of sufficiently small particles of metal could start a fire if reacted with water (NPFA 654, 2013, n.d.). This was the central hypothesis of the largest yet fire incident involving dust collection. It took the lives of 185 people and destroyed an entire production plant in China.
• In another instance involving baghouses, it was estimated that the quantity of dust entering the filters was less than 1% of the minimum explosible concentration (MEC) in the filter bags. During bag cleaning, however, when workers would shake the collected dust in the filter bags, manually dispersed dust was capable of producing dust clouds with explosible concentrations (G.Li, 2016).

Conducting or commissioning a Dust Hazard Analysis is critical to understanding the kind(s) of dust a facility generates, and preparing the appropriate procedures for hazard mitigation where combustible and explosible dusts are present.

Wet dust collectors vastly reduce the risk of sparks, fire and explosion. They are a clean, practical solution to a vexing issue that all facilities face.

Tri-Mer has longest, best track record with this important hazard mitigation tool. Talk with us about how we can meet your dust collection needs.