Whether from groundwater or surface water sources, the availability of and access to water that meets quality and quantity requirements is a critical need across the world.
Industry carries a large chunk of responsibility when it comes to the management, efficient use and saving of this scarce resource. When it comes to mining, water is used within a broad range of activities, including mineral processing, dust suppression, slurry transport, and employee requirements.
Over the last few decades, the industry has made much progress in developing closed-circuit approaches that maximise water conservation; however operations are often located in areas where there are significant competing municipal, agricultural and industrial demands.
Of late, there has been significant growth in the use of mechanical seals across processing industries.
Specifically, the mining industry presents many application challenges; for example, a scarcity of seal water and high-pressure transport slurry pump applications demands the development of innovative solutions.
Seals manufactured by AeSSeAl® have been used successfully in a variety of applications, even mining, in addressing these said challenges. The growth in mechanical seal use can be attributed to a number of factors; for one, traditionally, many sites used mechanical packing in their pumps.
However, the introduction of smaller pumps operating at higher speeds made mechanical packing a less desirable sealing alternative. Additionally, stringent health and safety regulatory controls have made product leakage unacceptable. Then there’s the obvious financial implications of leakage.
As the cost of raw materials increases, so has the need for reliable fluid sealing, and the yield loss of expensive process fluids can be reduced by positively sealing the process equipment. Another reason is that mechanical packing damages the rotating equipment. Shaft sleeve wear and bearing failure caused by excessive leakage are common complaints among clients.
More so, the chemical attack of the concrete base and ductile iron pump components occurs when corrosive chemicals are allowed to leak from packed glands. Mechanical seals have also become a preferred option because the periodic maintenance associated with alternatives demands the need to constantly monitor and adjust packed glands.
Reductions in costly flush water can occur when using properly designed and specified mechanical seals. The cost of clean water, process evaporation and wastewater treatment makes the conversion to mechanical seals beneficial and cost-effective.
Finally, most seal chambers operate under vacuum conditions; positive sealing from properly designed mechanical seals eliminates air ingress through the seal housing.
Mechanical seals and water management systems designed and manufactured by AeSSeAl® have been used successfully in a number of industries, including the processing industry.
AssEAl® water-saving solution
AeSSeAl®, which recently celebrated its 40th year in business, has developed a range of modular systems that have introduced a unique approach to mechanical seal support methodology.
One of the first systems to use this revolutionary concept was the SW02 water management system. AeSSeAl® has since sold thousands of water management systems, usually in combination with the CDSA double seal, a modular seal ideal for the containment of hazardous process fluids.
The systems are maintenance-friendly, requiring no external compressed air or gas pressurisation. They are also largely self-regulating and self-operating and do not require any manual intervention for refilling, with the total annual operating cost of a CDSA seal and SW02 water management system providing typical return on investment in 200 days.
The largest diamond mine in the world, located in an extremely arid region of Africa, and where water is a scarce resource, utilised AeSSeAl® water-saving solution. large Warman F-frame pumps were sealed with gland packing that required 19 gpm of gland water per pump.
To reduce water consumption in 2004/5, double mechanical seals and tank systems were fitted to 18 Warman X4 e-frame, and 12X10 F-frame slurry pumps at Plant #2. Currently, these 18 seals are running successfully, with reported total savings of 1.1 billion gallons of water with a value (in this desert country) of US$3.9 million (R56.6 million).
From a holistic perspective, financially and in managing environmental impacts, double mechanical seals and tank systems eliminate a number of problems associated with packing and can greatly reduce a mine’s water footprint. This occurs while also reducing the human capital required to care for the packing and increasing the uptime of equipment.
In those cases where the process is sensitive to dilution, double mechanical seals can save millions of dollars per year in lost product – which is an incredible win for the mining industry.