Dave Blane, director of Donaldson’s Industrial Filtration Solutions (IFS) division says about 50% to 60% of his division’s business relates to mining and metallurgy. It provides turnkey dust collection and ambient air filtration systems for mines. These collection systems protect people, equipment and the environment and in many cases recover valuable material. “In platinum mining this dust is collected and recovered and the platinum group metal (PGM) content pays for the cost of the installed system within months or even weeks.
“The IFS division undertakes projects that are of a capital nature, such as installing air filtration systems for large machinery and plant,” Blane says. “The capital expenditure from such projects accounts for about 60% to 70% of the division’s income. Repairs and replacement parts account for the rest.
“Often there is value to be extracted from the collected dust, but sometimes it is just a nuisance and the client says to us, ‘please just make the dust go away’.” This dust filtration is required in materials handling, smelting, and crushing and screening settings. In some cases the rate of dust collection is only a few kg/hour while in material recovery systems it can be many tonnes per hour.
“The filtration media used are important,” Blane says and an example of this is Donaldson’s patented Ultra-Web technology made with an electrospinning process that produces a very fine continuous fibre of 0.2-0.3 micron in diameter. These nanofibres form a permanent web-like net with very fine interfibre spaces that trap dust on the surface of the media, which is cleared by means of pulse cleaning.
Blane says that Donaldson has also embarked on the manufacture of its own filter bags. Like many companies that look to service the mining industry in a specialist field Donaldson has positioned itself as a one stop shop, for filtration requirements. It supplies bag filters, cartridge filters and cyclones and it uses a variety of materials in the manufacture of its various filters, including polyester, glass fibre and PTFE.
“Cartridge based dust collectors can achieve an efficiency of 99.997% on 0.5 micron particles. This high efficiency is often required when collecting toxic or radioactive dusts. Discharge levels from the collection system can be as low as 2 mg/m3 depending on the nature of the material being collected.
“We have a fully equipped and trained service team that is able to service and maintain all makes of dust collectors and we often enter into service agreements with large users of this equipment.” The company’s push into servicing original equipment in the field has been welcomed by OEMs as many users do not have the resources or skills to this in-house.
Donaldson’s manufacturing facility is based in Epping, Cape Town and a distribution and sales office is located in Modderfontein, where it designs filtration systems and looks to offer solutions. The Modderfontein facility has a service department and assembles smaller filtration components. It subcontracts the larger scale fabrication to contractors on the Reef.
However, unlike the company, which is almost a century old, Blane’s projects division is relatively new. It is smaller than that managed by Donaldson sales director Rob Simpson, which covers hydraulic and heavy duty automotive filters. This encompasses fuel and lubrication filters, coolants and coolant filters, fuel filter water separators, transmission filters as well as air filters and related accessories
“Today’s heavy-duty engines operate at high injection pressures, which makes them more vulnerable to contaminated fuel. The machined tolerances are lower and with smaller sumps these modern engines are even more susceptible to dirt ingress,” Simpson says. “It places a greater emphasis on good quality high efficiency filters than ever before. The filters have to work harder."
Vehicle operators understand the advantages of extending the vehicle’s service life. This results in a greater awareness on condition monitoring techniques. “Proactive maintenance, though, means a lot more than simply replacing a filter when necessary; it involves looking at the filtration system as a whole.” The filtration system in modern mobile mining equipment is complex with specialised filtration used throughout the machine to ensure optimum protection within given operating environments.
Among these filtration systems are air pre-cleaners that filter out 90% of the dust before it enters the air cleaner. There is a variety of products and accessories from standard to premium long life filtration products, which incorporate high efficiency synthetic media as part of Donaldson’s endurance range.
In line with its positioning as solutions based service provider, Donaldson has also extended its expertise to upstream filtration on bulk storage tanks, to ensure contamination control prior to product entering a vehicle. One of the big filtration issues it has to deal with in Africa is the risk of fuel contaminated with water, where coalescing filters are used to remove any water from the diesel.
“We are selling extra engine life, and to achieve this you need quality products and expertise,” Simpson says. “The problem is that the cost benefits are sometimes only proven at the end of the equipment’s life, so it means building a reputation and customer confidence to the extent that people trust the Donaldson products, service and technology.”
In South Africa Donaldson has multiple distributors, which are filter specialists in their own right and the company is looking at implementing its filtration services into the rest of Africa backed up with the support of a further 17 distribution outlets. “When looking at what we can offer a fleet in Africa, the first thing we do is survey the operating conditions and environment to understand the customer’s needs.”
Approximately 45% of Donaldson’s business is in the heavy duty automotive engine sector with products being particularly well suited for harsh operating environments found in mining. Donaldson is one of the few filtration companies that can find a product to meet almost every requirement, from industrial, to engine, to compressed air and various specialised industries. It spends about 2% to 3% of its profit on R&D and has a nanotechnology division, filtration being an area where nanotechnology developments could have large impacts. Overall the company employs 11,000 people worldwide, of whom 400 are engineers.