Dust-A-Side have designed, installed, commissioned and are currently fine-tuning a dust suppression system at a mine site preparation plant* in Australia.
*The clients’ name has been withheld for confidentiality reasons.
About the site
At the plant, which is an intrinsic part of a 27,000+ hectare mine site, export-quality hard coking coal is processed and made ready to be loaded onto coal trains for the over 350km trip to the coal terminal.With approximately 12 million tonnes of rich black coal produced annually and over 900 people employed on the site, it is not without its challenges with dust control – and Dust-A-Side Australia was commissioned to use their experience and expertise in dust suppression systems to solve the problem.
Prior to Dust-A-Side commissioning the state-of-the-art dust suppression system, there was so much dust generated – particularly during the crusher/breaker and screening processes in which the fines are separated from unusable coal and reject material – even 5-minutes exposure was proving problematic.Clearly, this was having an impact on productivity and safety, and an all encompassing solution needed to be implemented.
Dust prevention and dust suppression at its finest
As you can well imagine, being such a massive site and with such high yield, there are numerous dust generation points – the result of vast amounts of coal transported overland to the 30-year old plant via conveyors and trucks.
Dust-A-Side Australia has taken a two-pronged approach to controlling dust at the site, using:
- A Dust Prevention System to eliminate dust through the entire process (such as low pressure systems), and
- A Dust Suppression System at key transfer points that are high dust generation areas (high pressure systems).
Smart misting systems
The primary area requiring dust suppression is the tip area, where coal is tipped in from the conveyor and by trucks into large bins creating humungous plumes of dust.
To solve this problem, Dust-A-Side have utilised existing sensors to auto-activate the systems.
“Weight On Belt” sensors on the conveyor set to specified levels (eg 1,500 tonnes) automatically activates the system, as do trucks picked up on radar.
On cue, a pre-programmed misting system creates a wall of fine mist through which the coal passes.
Other methods of suppressing dust at the site include the use of fog cannons in tip areas and spray bars with fans to force the spray even further into the feed bin.
As it has been designed to operate at high pressure using low volumes of water, there is never an issue with over-wetting the coal.
The control room for this dust suppression system is housed in a modular designed climate-controlled shipping container housed on a concrete pad.
It operates a system of hoses and features special solenoids that give operators the ability to control which areas need spraying, and to what extent.
Flexibility is the key; as different types of coal generate varying degrees of dust, it allows the operators to focus on problem areas.
Dust-A-Side has added embedded remote-control functionality to the existing CHPP control room. As well as being operated and managed remotely, this can also be used to pre-empt faults.
An independently certified real-time, lightscatter Aerosol monitor was used to measure PM10 dust levels adjacent to the CHPP once the system had been commissioned.
A total of 529 valid data points were obtained during the monitoring period, with a summary of the results comparing the dust levels observed with the system turned on and turned off shown in the following table.
As you can further see from the inset graph, the customised and purpose-built dust suppression system delivered by Dust-A- Side has had a huge impact in reducing the overall amount and variability of PM10 sized dust levels at the mine site. This is the type of respirable dust that has been associated with black lung.
With and without a Dust-A-Side dust suppression system operating. Concentrated Dust Particles per square mml at the bottom of a tip area handling raw coal at the Australian mine site.
How we’ve further enhanced this dust suppression system
To further enhance the dust suppression systems at the site and reduce the use of water, Hydrowet (a Dust-A-Side exclusive product) has since been incorporated into the system.
Hydrowet is particularly useful when materials such as coal and other ores have finer particles of dust, as it helps to break the surface tension of water particles. The smaller water droplets attract finer dust particles to them, via agglomeration.
Importantly these products are automatically dosed by the system and only added when required, therefore helping to keep running costs down whilst also maximising the performance of the system.
No one knows more about dust suppression and dust control
With more than 200 highly advanced dust suppression systems in operation globally, Dust-A-Side is an acknowledged leader in this field.
To find out more about dust prevention and dust suppression systems, call 1800 662 387 and speak to our ever-helpful team members, or simply click here to contact us.