Less waste means more reliability

Water waste is commonly deemed an undesirable, however inevitable by-product of mining processes. Yet fashionable pump sealing know-how exists which might nearly remove this waste while conserving vitality, improving pump reliability and achieving long term operational savings.
Water is among the most vital, and increasingly imperilled, assets on earth. That a lot is known and acknowledged by industries across the globe.
However, additionally it is one of the unnecessarily squandered assets in mining operations. And while the industry has begun to embrace effectivity and sustainability-led advances such as automation and renewable vitality, it remains steadfastly set in its methods when it comes to slurry pump expertise.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also generally recognized as ‘dynamic’ seals’) and single mechanical seals. All include significant limitations, including poor reliability, reduced mean times between failure (MTBF), intensive maintenance requirements and higher operational prices.
These elements alone should give mine managers trigger for a re-evaluation of the sealing methods used on slurry pumps. However, any company with a dedication to the International Standards Organisation ISO-14001 Standard for environmental management methods and ISO-50001 Standard for vitality management methods ought to pay consideration to the extreme water waste and excessive vitality consumption that outcomes from opting for 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 elements of slurry processing which is seal flush water injection.
On gland packed pumps it’s essential that packing is flushed with clean water to maintain it cool and lubricated, whereas each single slurry seals and expellers require a provide of cool, clear flush water to be injected into the process at excessive strain, maintaining a stable fluid film between the delicate seal faces to maintain them cool and lubricated, while forcing the damaging slurry away.
The flush water required in all three sealing approaches is equipped from an external source and injected into the method at a higher stress than the stuffing box stress, in line with the trade standard American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the ground or into the process is sent to the tailings dam. This additionally has an impact on the water stability of the plant.
This strategy constitutes a lack of clear water amounting to billions of gallons a year globally. weksler pressure gauge ราคา , typical slurry pump usually consumes 10 US gallons (37.eight litres) per minute, amounting to five.2 million US gallons (19.6 million litres) of water yearly – a surprising statistic by any measure.
At a time when international water provide is predicted to fall in want of demand by some 40% by 20301 , eradicating pointless use of this useful useful resource should arguably be a central plank of any responsible sustainability programme. Yet excessive water use, and the higher energy consumption it entails, remain embedded within the processes of many mining corporations. Worse still, it is honest to say that it is often accepted as simply ‘par for the course’ by reliability engineers and administration alike.
But the fact is that water waste on any scale is a totally pointless feature of slurry operations as it might be virtually completely eradicated simply by using superior double mechanical seals and fashionable water administration support methods.
Improve reliability The sort of seal chosen, the setting by which it operates, and crucially, the tank help system which provides the water to maximise seal life, combine to supply the solution to extreme water waste and energy use.
Modern double mechanical seals have two sets of faces, one sealing to the process fluid and one to environment, with a barrier area between the 2. They are designed to satisfy the arduous requirements of heavy duty slurry functions, with fortified metal parts which are highly immune to corrosion and erosion. Large ports and elevated radial clearances imply the lubrication which is significant to optimising seal life is maintained continually and persistently.
A pressurised barrier tank system is central to the environmental sustainability of this resolution. It employs a thermosiphon process which supplies clear, cool water to the barrier area between the double seals at a pressure higher than the product strain, making certain a constant, secure and clean fluid film to keep the seal faces cool and lubricated.
As the mechanical seals generate warmth, the recent water in the barrier house rises to the tank and is radiated to the atmosphere, permitting the cooler, denser water to sink again down to offer cool lubrication to the seal faces. Most importantly, the flush water is constantly recycled, flowing across the seal faces in a continuous loop and decreasing leakage to the absolute minimum, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing multiple slurry pumps in a ‘series train’ with out the need to set up special pump systems, pressurised barrier tanks provide rankings as much as 435 psi (30 bar), making them ideal for these functions. Self-topping and self-pressurising, they’re also almost maintenance-free.
Where no plant water supply is on the market for topping up the tank methods, or the availability has inadequate stress, fluid supply units may be selected to produce 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 provide freeze safety in extraordinarily cold climates.
Wide-ranging benefits The benefits of upgrading to modern sealing options and support methods have been felt by a coal mine in Poland using a slurry pump to produce coal mud at 9 bar (135 psi) to filter press. Flushed packing resulted in large dilution of product, leading to significantly increased filtration occasions and prices. The pump was sealed with a double mechanical seal designed to meet the arduous requirements 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 popularity enhanced.
The mining trade should take care of a tricky and expensive challenge in terms of maintaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and monetary burden which is completely avoidable.
And when an organization can remove water waste simultaneously increasing reliability and decreasing long run operational prices, the decision to upgrade to modern methods should certainly be a moral imperative in addition to making sound business sense.
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