Sunday 18th Aug, 2019

Keeping dust down in concrete batching plants

Enmin Vibratory Equipment has developed a solution to keep concrete flowing in batching plants while reducing dust emissions.

Enmin Vibratory Equipment has developed a solution to keep concrete flowing in batching plants while reducing dust emissions.

Environmental protection authorities (EPA) around Australia have guidelines for dust control to prevent excessive dust generation during loading and unloading.

EPA Victoria explains airborne dust reduces air quality and may have adverse effects on health, while a construction materials company was fined thousands of dollars by the NSW EPA for poor dust management.

One of the most common ways to reduce dust in concrete batching plants is to keep the material moist, though this can have negative impacts on material flow characteristics.

Moist materials on a hot day can lead to a bin or silo drawing moisture into the holding material, making it sticky and difficult to move. Additionally, natural compaction means the material may become trapped within the bin or silo, significantly impacting a plant’s ability to ensure materials such as fly ash, sand, gravel or aggregates flow in a safe and efficient manner.

This was the problem Enmin Vibratory Equipment was tasked to solve for an Australian concrete batching plant with a steel holding silo.

The solution the company would implement was the installation of an industrial turbine vibrator, which was able to meet EPA guidelines for both dust and noise control. It operates at around 10,000 vibrations per minute, transferring high frequency but low amplitude forces to break the particle bonding and promote material flow.

Turbine vibrators use centrifugal force generated by an unbalanced rotor to provide vibratory forces. They require no lubrication which significantly reduces the amount of maintenance required and makes them ideal for hygienic environments.

Due to their design, turbine vibrators produce less noise than standard vibrators and are often significantly quieter than factory requirements.

After seeing how effectively the vibrator operated, the customer installed a further seven throughout its plants.

Positioning was key for the turbine vibrator, because if it was placed incorrectly, it could have led to further compaction of the material. For this reason, Enmin performs full site audits and inspections to best understand where to install its equipment.

Bulk concrete transport operations also often face compaction problems, especially when t long distances or poor road conditions are involved. When a load arrives after a long or bumpy journey, the bulk of the material may discharge easily but a significant amount can be left clinging to the trailer body.

To counteract this, truck operators are often forced to raise the body of the trailer high and rock the truck to dislodge the materials, posing potential safety risks and increasing wear on the vehicle’s brakes, clutch and hydraulics.

Industrial vibrators can help provide a cost-effective solution for these tip trucks, with the operator able to remain within the cabin as the device removes compacted materials from the trailer.

Industrial vibrators for the mining, quarrying and transport industries can’t take a one-size-fits-all approach due to the vast potential combinations of materials and equipment design. There are a wide variety of industrial vibrators, including electric, hydraulic and pneumatic models.

For example, aluminium components can’t be used for underground mining operations due to the risk or sparking against rusty steel, meaning the material components used for a vibrator need to be taken into consideration.