Water is the most precious commodity on our planet. The challenge of its conservation with an ever-growing population is the responsibility of us all. Within the mining industry, there are many opportunities to do this.
Yet, one that's often ignored for those mistakenly perceived as bigger-ticket items is that of optimising the packing and seals used in rotating equipment.
Overlooked Areas of Water Use Reduction
Slurry pumps, in particular, are an area where operators stand to make considerable savings through the proper selection of pump sealing components. Flushing systems are traditionally used to ensure the optimal operation of the sealing element. Yet every litre of this water costs - both on a commercial and environmental scale.
Utilising the right mechanical seal design and/or carefully chosen packing can dramatically reduce, or even eliminate, the amount of flush water used. For assets that are typically running 24/7/365, this represents a significant area in which to decrease costs.
Minimal or flush-free sealing methods are seen as the gold standard in reducing wastewater and, in addition to the cost aspect, can dramatically assist with adherence to the multitude of water regulations to which Australian mining operations must comply.
The Importance of Packing and Mechanical Seals
For applications where product leakage is not acceptable, the choice of mechanical seals that require no flush water is critical. This promotes savings in both product dilution and those associated with flush water treatment. The crucial aspect is through the selection of seals offering extended longevity and ease of installation, thus reducing both planned and emergency asset downtime.
Both single and dual mechanical seals are designed for slurry applications without a flush.
- Single mechanical seals: These provide maximum clearance around moving parts. This prevents clogging and, combined with tighter face loading, also reduces the build-up of particulate contamination. Depending on the level of solids in individual applications, such seals may require an environmental controller to remove them.
Find out more about Chesterton 170 Slurry Single Cartridge Seal https://chestertonrotating.chesterton.com/en-us/Products/Pages/170.aspx
- Dual mechanical seals: Severe slurry applications require double seals and environmental controls. A barrier fluid tank used in conjunction with the seal provides the water conservation.
In cases where slight leakage is appropriate/acceptable, best sealing practice is attained through packing. Because the flush water is reduced or virtually eliminated then the aspect of heat resistance in the packing is a crucial element.
There are different packing options, with today's technology providing many advantages over traditional standard pump packing.
- Injectable packing: Made of a heat-resistant thermoset material, this hybrid cross between liquid and solid is injected into the stuffing box through the lantern ring flush port. It has many advantages, including the ability to be used in many applications, reduces or removes the need for a flush to cool the packing and can be re-energised while the pump is rotating (subject to utilising the manufacturer's injection system)
- Carbon/graphite packing: Offering a high-temperature capability with low heat generation and excellent thermal conductivity, this has often been associated with wear and extrusion issues. However, the most advanced technologies have virtually eliminated such problems, meaning high-end graphite filled packing has a dramatically extended lifespan when used in severe service applications, such as ore and mineral handling slurries.
Chesterton Seals: Bringing dynamic solutions to the challenge of water reduction
Sustainable water management within the mining industry is at a critical stage. Not only is a global shortage a looming catastrophe, but the cost of the water itself and its scarcity in many remote mining locations adds up to billions of dollars per year. Mining operations that look to initiatives to reduce their water usage and wastage can benefit from savings of millions per annum.
Chesterton is committed to bringing the latest solutions to the mining industry. From single and dual mechanical seals through to the Chesterton DualPac® 2211 and 2212 (a graphite-filled ePTFE that resists consolidation without shaft wear that offers extended life in the most aggressive of slurry applications), their global reach is tailored to assisting operations to reduce water use and wastage.
Now available within Australia, Chesterton provides unique technologies for high-performance sealing solutions and equipment protection within the increasingly competitive landscape of the mining industry.
Find out more at www.chestertonrotating.chesterton.com
More on Chesterton solutions for the slurry industry https://www.miningmonthly.com/1385348