Dust Down™

Dust Suppression Liquid

Introduction

The Occupational Health and Safety Act, states that every employer shall provide and maintain, as far as reasonably practicable, a working environment that is safe, and without risk to the health of his/her employees. The presence of dust is a fact of life in many industries which handle or process a product such as coal, mineral ores and many others. It’s a constant effort to control dust emission.

What is dust?

Dust is defined as solid particles of sizes ranging between 0.1 to 100 μ (micron). Within this range, we have respirable dust is found up to 7μ. While all dust should is to be controlled to specified threshold limits, respirable dust is more important, especially where the dust is toxic. Airborne dust particles can be difficult to remove due to the fact that they are so small in size (0.1 to 10 microns). These particles drift everywhere and can be a significant health hazard. Respirable dust is not easily visible. Thus the absence of visible dust does not mean there is no dust at all. Dust is anything which escapes from a mechanical handling plant to become nuisance dust. This fugitive dust needs to be controlled.

What is dust control?

As prevention is largely impossible, limitation must be the focus.

Dust suppression types

There are two types of suppression methods.

Wet suppression - 1. objective is to bind dust and particles to the main product and prevent liberation during handling. However, to wet the product has its shortcomings. It can result in excessive water usage and also lead to excess moisture content in the product which may not be desirable. This method cannot be used on products which have any affinity to water.

Fine water mist -2. Engineers often look to control the problem by spraying a fine water mist to capture dust particles. The proven theory of the system is that if the dust and water particles are about the same size, they can and do bond. (Ventilation & transfer points)

• This is due to the fact that large droplets (80 to 100 microns) will travel through the air and collide with very few particles on the way.
  
• The air stream traveling around the much larger droplet deflects the dust particle away from the drop
  let, thus avoiding collision.
  
• To capture a dust particle in the best possible manner it is required that the water droplets be the same size and weight as the dust particles.
  

Airborne dust - suppression with Dust Down™

• How can the introduction of a surfactant help? Softening the water solves the following problems;
  
• We are concerned with dust, particularly in the 1μ to 7μ range, this means droplets must be within this range for optimum results to be achieved. Soft water(reduced surface tension) forms small droplets easier and quicker that hard water.
  
• Small droplets are created by energy being released at the nozzle. If this energy is insufficient, small droplets must then develop by evaporation. This is not ideal as it takes time to evaporate to the correct
  size. Droplets are directly effected by climatic conditions, yielding inconsistent results.

Before and after mist application

Coal mine: Without Dust Down™	With Dust Down™
Iron ore: Without Dust Down™	With Dust Down™
Diamond mine: Without Dust Down™	With Dust Down™
Gold mine: Without Dust Down™	With Dust Down™

Surface dust - suppression with Dust Down™

Stubborn dust clouds stirred by heavy vehicles are a constant concern on open pit mining operations and trafficked gravel roads (such as construction sites). Dust inhalation poses a health hazard, and, when it obscures visibility, becomes a prominent safety risk as well. Coupled with environmental concerns regarding plant life and air quality, dust is a challenge that needs to be adequately and sustainability dealt with.

Traditionally, water was being sprayed in the pit in an attempt to control the dust, however, this was not a very effective solution as the areas had to be sprayed six times a day. This involved a water truck traveling rugged roads and long distances back and forth to the pits, consuming large amounts of diesel, and, of course, using copious amounts of water. DUST DOWN™ is a bio-surfactant, which increases the ability of water to penetrate the road surface which enhances the suppression of dust.

Find out more: info@greensense.ae