Less waste means more reliability

Water waste is usually deemed an undesirable, but inevitable by-product of mining processes. Yet modern pump sealing technology exists which may just about remove this waste while conserving vitality, bettering pump reliability and achieving long term operational savings.
Water is among the most vital, and increasingly imperilled, assets on earth. That much is known and acknowledged by industries throughout the globe.
However, it is also one of the unnecessarily squandered sources in mining operations. And while the business has begun to embrace effectivity and sustainability-led advances similar to automation and renewable energy, it stays steadfastly set in its methods when it comes to slurry pump know-how.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also known as ‘dynamic’ seals’) and single mechanical seals. All include vital limitations, including poor reliability, lowered imply times between failure (MTBF), intensive maintenance necessities and higher operational costs.
These components alone should give mine managers cause for a re-evaluation of the sealing strategies used on slurry pumps. However, any company with a commitment to the International Standards Organisation ISO-14001 Standard for environmental administration methods and ISO-50001 Standard for power administration systems ought to pay consideration to the extreme water waste and high power consumption that outcomes from choosing these conventional sealing methods.
Inefficient sealing When used to seal the method pumps in a mine’s scrubber and floatation circuits, gland packing, single mechanical seals and expeller seals all demand one of the most wasteful aspects of slurry processing which is seal flush water injection.
On gland packed pumps it’s important that packing is flushed with clean water to keep it cool and lubricated, whereas both single slurry seals and expellers require a supply of cool, clear flush water to be injected into the process at excessive strain, maintaining a secure fluid film between the fragile seal faces to maintain them cool and lubricated, while forcing the damaging slurry away.
The flush water required in all three sealing approaches is provided from an exterior source and injected into the process at a better strain than the stuffing field pressure, consistent with the trade commonplace American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the bottom or into the process is shipped to the tailings dam. This additionally has an impact on the water balance of the plant.
This method constitutes a loss of clear water amounting to billions of gallons a year globally. One giant, conventional slurry pump usually consumes 10 US gallons (37.8 litres) per minute, amounting to five.2 million US gallons (19.6 million litres) of water every year – a surprising statistic by any measure.
At a time when international water supply is predicted to fall in want of demand by some 40% by 20301 , eradicating unnecessary use of this valuable useful resource ought to arguably be a central plank of any responsible sustainability programme. Yet extreme water use, and the higher power consumption it entails, remain embedded in the processes of many mining firms. Worse still, it’s fair to say that it’s typically accepted as merely ‘par for the course’ by reliability engineers and management alike.
But the fact is that water waste on any scale is a totally pointless feature of slurry operations as it may be almost totally eliminated simply by employing advanced double mechanical seals and fashionable water management support methods.
Improve reliability The type of seal selected, the surroundings during which it operates, and crucially, the tank help system which provides the water to maximise seal life, combine to supply the solution to excessive water waste and power use.
Modern double mechanical seals have two units of faces, one sealing to the method fluid and one to environment, with a barrier area between the two. pressure gauge ราคา ถูก are designed to meet the arduous necessities of heavy responsibility slurry purposes, with fortified metallic elements which are extremely immune to corrosion and erosion. Large ports and elevated radial clearances imply the lubrication which is important to optimising seal life is maintained constantly and constantly.
A pressurised barrier tank system is central to the environmental sustainability of this solution. It employs a thermosiphon course of which provides clear, cool water to the barrier space between the double seals at a stress larger than the product stress, ensuring a consistent, secure and clean fluid film to maintain the seal faces cool and lubricated.
As the mechanical seals generate heat, the new water within the barrier area rises to the tank and is radiated to the ambiance, permitting the cooler, denser water to sink again down to offer cool lubrication to the seal faces. Most importantly, the flush water is continually recycled, flowing across the seal faces in a steady loop and decreasing leakage to the absolute minimum, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing a number of slurry pumps in a ‘series train’ without the necessity to install special pump methods, pressurised barrier tanks provide ratings up to 435 psi (30 bar), making them perfect for these purposes. Self-topping and self-pressurising, they’re also almost maintenance-free.
Where no plant water provide is out there for topping up the tank methods, or the availability has inadequate pressure, fluid supply items could be selected to supply the barrier fluid to seal faces. These have the added advantages of being in a position to supply a water/glycol mixture or oil to supply freeze safety in extremely cold climates.
Wide-ranging benefits The benefits of upgrading to fashionable sealing options and help methods were felt by a coal mine in Poland utilizing a slurry pump to produce coal mud at 9 bar (135 psi) to filter press. Flushed packing resulted in big dilution of product, leading to greatly increased filtration times and prices. The pump was sealed with a double mechanical seal designed to meet the arduous necessities of the method.
The supporting seal tank system reduced leakage and product dilution to just about zero. Return on funding was swift and the savings long-term. The benefits when it comes to water conservation have been equally longlasting and the company’s reputation enhanced.
The mining industry must cope with a tough and dear problem in terms of maintaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and monetary burden which is entirely avoidable.
And when an organization can remove water waste concurrently growing reliability and lowering long term operational costs, the decision to improve to fashionable techniques should absolutely be a moral imperative as properly as making sound enterprise sense.

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