Less waste means more reliability

Water waste is commonly deemed an undesirable, however inevitable by-product of mining processes. Yet modern pump sealing expertise exists which may virtually eliminate this waste while conserving vitality, improving pump reliability and achieving long term operational financial savings.
Water is amongst the most vital, and increasingly imperilled, sources on earth. That much is known and acknowledged by industries throughout the globe.
However, it’s also some of the unnecessarily squandered assets in mining operations. And whereas the business has begun to embrace effectivity and sustainability-led advances similar to automation and renewable vitality, it stays steadfastly set in its ways when it comes to slurry pump know-how.
Three approaches are routinely specified by pump manufacturers to seal slurry pumps: mechanical packing, expellers (also generally identified as ‘dynamic’ seals’) and single mechanical seals. All include important limitations, together with poor reliability, decreased imply instances between failure (MTBF), intensive upkeep necessities and better operational prices.
เพรสเชอร์เกจดิจิตอล should give mine managers trigger for a re-evaluation of the sealing methods used on slurry pumps. However, any firm with a dedication to the International Standards Organisation ISO-14001 Standard for environmental management techniques and ISO-50001 Standard for power management techniques ought to pay attention to the extreme water waste and high power consumption that outcomes from choosing these traditional sealing strategies.
Inefficient sealing When used to seal the process pumps in a mine’s scrubber and floatation circuits, gland packing, single mechanical seals and expeller seals all demand one of the most wasteful features of slurry processing which is seal flush water injection.
On gland packed pumps it’s essential that packing is flushed with clear water to maintain it cool and lubricated, whereas both single slurry seals and expellers require a supply of cool, clear flush water to be injected into the method at high pressure, sustaining a secure fluid movie between the delicate seal faces to maintain them cool and lubricated, whereas forcing the damaging slurry away.
The flush water required in all three sealing approaches is supplied from an external source and injected into the method at a higher stress than the stuffing field strain, in line with the business commonplace American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the bottom or into the method is shipped to the tailings dam. This also has an impact on the water balance of the plant.
This strategy constitutes a loss of clear water amounting to billions of gallons a 12 months globally. One massive, conventional slurry pump usually consumes 10 US gallons (37.8 litres) per minute, amounting to 5.2 million US gallons (19.6 million litres) of water every year – a surprising statistic by any measure.
At a time when world water provide is predicted to fall wanting demand by some 40% by 20301 , removing pointless use of this priceless useful resource ought to arguably be a central plank of any accountable sustainability programme. Yet excessive water use, and the higher vitality consumption it entails, stay embedded in the processes of many mining corporations. Worse still, it’s honest to say that it is typically accepted as simply ‘par for the course’ by reliability engineers and administration alike.
But the very fact is that water waste on any scale is a completely unnecessary feature of slurry operations as it may be nearly completely eradicated simply by using advanced double mechanical seals and trendy water administration help techniques.
Improve reliability The sort of seal selected, the surroundings in which it operates, and crucially, the tank support system which supplies the water to maximise seal life, mix to provide the solution to excessive water waste and vitality use.
Modern double mechanical seals have two units of faces, one sealing to the method fluid and one to ambiance, with a barrier area between the two. They are designed to meet the arduous necessities of heavy obligation slurry functions, with fortified steel parts that are highly resistant to corrosion and erosion. Large ports and increased radial clearances mean the lubrication which is significant to optimising seal life is maintained constantly and consistently.
A pressurised barrier tank system is central to the environmental sustainability of this answer. It employs a thermosiphon course of which provides clean, cool water to the barrier area between the double seals at a strain greater than the product stress, making certain a consistent, steady and clear fluid film to maintain the seal faces cool and lubricated.
As the mechanical seals generate warmth, the hot water in the barrier space rises to the tank and is radiated to the environment, allowing the cooler, denser water to sink back down to provide cool lubrication to the seal faces. Most importantly, the flush water is constantly recycled, flowing throughout the seal faces in a steady loop and decreasing leakage to the absolute minimal, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing a quantity of slurry pumps in a ‘series train’ with out the necessity to install special pump techniques, pressurised barrier tanks supply rankings up to 435 psi (30 bar), making them best for these purposes. Self-topping and self-pressurising, they are also virtually maintenance-free.
Where no plant water supply is available for topping up the tank systems, or the supply has inadequate strain, fluid supply models may be chosen to produce the barrier fluid to seal faces. These have the added benefits of having the ability to supply a water/glycol mixture or oil to provide freeze protection in extremely chilly climates.
Wide-ranging advantages The benefits of upgrading to trendy sealing solutions and support techniques were felt by a coal mine in Poland utilizing a slurry pump to supply coal mud at 9 bar (135 psi) to filter press. Flushed packing resulted in huge dilution of product, resulting in tremendously elevated filtration instances and costs. The pump was sealed with a double mechanical seal designed to satisfy the arduous necessities of the process.
The supporting seal tank system decreased leakage and product dilution to virtually zero. Return on investment was swift and the savings long-term. The advantages by way of water conservation have been equally longlasting and the company’s status enhanced.
The mining trade should deal with a tricky and dear problem in relation to sustaining rotating tools. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is completely avoidable.
And when an organization can remove water waste simultaneously growing reliability and decreasing long term operational prices, the choice to improve to fashionable methods should absolutely be an ethical crucial as well as making sound business sense.
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