Specialised engineering solutions provider RTS Africa Engineering is receiving an increasing number of enquiries from various markets, such as sub-Saharan Africa, Australia and India, for its inertial spin filters used in small to medium-sized mining applications.

This increase in interest can be attributed to the inertial spin filters’ primary advantage of being virtually maintenance free – a very attractive feature in these difficult financial times when maintenance and the replacement of consumables, such as filters, can become extremely expensive, says RTS Africa.

The company explains that its inertial spin filters are an effective and practical solution for the challenges in the underground mining environment such as heavy dust loads generated by drilling and tunnelling.

These challenges also include health risks to underground mining personnel, damage to electrical equipment and increasingly rigorous environmental legislation, for example, strict regulations dealing with health threats from fine respirable dust particles which cause ptisis and other lung diseases.

RTS Africa MD Ian Fraser states that the problem is exacerbated by mine ventilation systems, comprising of large fans that force air down ducts into the mine shafts and underground working areas, carrying hazardous airborne dust in increasing quantities and densities.

He explains that the main problem faced by ventilation engineers is the manufacturing of a filtration system that will remove very fine dust and larger particles that could represent a health hazard to mineworkers. Such a system will require the continuous replacement of filter media, which is time consuming and costly.

Fraser points out that using the RTS inertial spin filters as primary filters to continuously remove heavy dust particles will mitigate this challenge by preventing the secondary fine filters from becoming rapidly overloaded and, subsequently, requiring frequent maintenance or replacement.

Moreover, RTS spin filters reduce or even eliminate downtime caused by failures in electrical systems, owing to dust contamination or overheating.

When using RTS inertial spin filters to clean the air in motor control centre (MCC) rooms, variable speed drives and control rooms, besides others, no secondary filtration is required. This eliminates the need for expensive, complex, high-maintenance bag houses, explains Fraser.

Owing to the constant pressure drop and absence of secondary process air or other energy- absorbing equipment, the spin filter installation is also energy efficient.

The RTS spin filters are made from high-density polypropylene and are highly resistant to wear, with some modules supplied by the company having been in service for more than 20 years. This is because the system is self- purging and there is no filter element that can become blocked because of dust overload .