Less waste means extra reliability

Water waste is commonly deemed an unwanted, however inevitable by-product of mining processes. Yet fashionable pump sealing technology exists which may just about get rid of this waste while conserving vitality, bettering pump reliability and achieving long run operational savings.
Water is certainly one of the most important, and more and more imperilled, resources on earth. That much is understood and acknowledged by industries throughout the globe.
However, it is also one of the most unnecessarily squandered resources in mining operations. And while the industry has begun to embrace effectivity and sustainability-led advances similar to automation and renewable power, it stays steadfastly set in its methods in phrases of slurry pump technology.
Three approaches are routinely specified by pump manufacturers to seal slurry pumps: mechanical packing, expellers (also often identified as ‘dynamic’ seals’) and single mechanical seals. All come with significant limitations, including poor reliability, reduced mean occasions between failure (MTBF), intensive maintenance requirements and higher operational prices.
These elements alone should give mine managers cause for a re-evaluation of the sealing strategies used on slurry pumps. However, any firm with a commitment to the International Standards Organisation ISO-14001 Standard for environmental administration methods and ISO-50001 Standard for vitality administration techniques ought to pay consideration to the extreme water waste and high power consumption that outcomes from opting for these conventional 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 some of the wasteful aspects of slurry processing which is seal flush water injection.
On gland packed pumps it’s essential that packing is flushed with clear water to keep it cool and lubricated, whereas each single slurry seals and expellers require a supply of cool, clean flush water to be injected into the process at high stress, maintaining a stable fluid movie 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 supply and injected into the method at a higher strain than the stuffing field stress, in line with the industry standard 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 also has an effect on the water steadiness of the plant.
This approach constitutes a lack of clean water amounting to billions of gallons a 12 months globally. One giant, typical slurry pump sometimes consumes 10 US gallons (37.8 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 world water supply is predicted to fall short of demand by some 40% by 20301 , removing pointless use of this priceless resource should arguably be a central plank of any responsible sustainability programme. Yet extreme water use, and the higher energy consumption it entails, stay 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 management alike.
But เกจวัดแรงดันไฟฟ้า is that water waste on any scale is a completely unnecessary characteristic of slurry operations as it might be almost completely eliminated just by using advanced double mechanical seals and trendy water administration support systems.
Improve reliability The kind of seal chosen, the setting by which it operates, and crucially, the tank help system which provides the water to maximise seal life, mix to offer the answer to extreme water waste and vitality use.
Modern double mechanical seals have two sets of faces, one sealing to the method fluid and one to atmosphere, with a barrier house between the two. They are designed to satisfy the arduous necessities of heavy obligation slurry applications, with fortified steel parts that are highly proof against corrosion and erosion. Large ports and elevated radial clearances imply the lubrication which is vital to optimising seal life is maintained constantly and persistently.
A pressurised barrier tank system is central to the environmental sustainability of this answer. It employs a thermosiphon course of which supplies clean, cool water to the barrier space between the double seals at a pressure higher than the product pressure, making certain a constant, stable and clear fluid movie to keep the seal faces cool and lubricated.
As the mechanical seals generate heat, the recent water within the barrier space rises to the tank and is radiated to the ambiance, allowing the cooler, denser water to sink back down to offer cool lubrication to the seal faces. Most importantly, the flush water is continually recycled, flowing across the seal faces in a continuous loop and reducing leakage to the absolute minimum, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing a quantity of slurry pumps in a ‘series train’ without the necessity to set up special pump techniques, pressurised barrier tanks supply rankings as much as 435 psi (30 bar), making them best for these functions. Self-topping and self-pressurising, they are also virtually maintenance-free.
Where no plant water supply is out there for topping up the tank techniques, or the availability has inadequate pressure, fluid delivery units may be chosen to supply the barrier fluid to seal faces. These have the added benefits of being in a position to supply a water/glycol mixture or oil to supply freeze safety in extraordinarily cold climates.
Wide-ranging benefits The benefits of upgrading to modern sealing solutions and assist systems 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 huge dilution of product, resulting in significantly elevated filtration occasions and costs. The pump was sealed with a double mechanical seal designed to fulfill the arduous necessities of the method.
The supporting seal tank system lowered leakage and product dilution to nearly zero. Return on investment was swift and the savings long-term. The advantages by means of water conservation have been equally longlasting and the company’s popularity enhanced.
The mining industry must take care of a troublesome and expensive problem when it comes to sustaining rotating equipment. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is entirely avoidable.
And when a company can eliminate water waste concurrently rising reliability and decreasing long run operational prices, the decision to improve to modern techniques should certainly be an ethical imperative as well as making sound business sense.
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