Less waste means extra reliability

Water waste is commonly deemed an undesirable, but inevitable by-product of mining processes. Yet fashionable pump sealing expertise exists which may virtually get rid of this waste while conserving power, enhancing pump reliability and reaching long run operational savings.
Water is amongst the most vital, and increasingly imperilled, assets on earth. That much is understood and acknowledged by industries across the globe.
However, it is also some of the unnecessarily squandered resources in mining operations. And whereas the business has begun to embrace efficiency and sustainability-led advances such as automation and renewable power, it stays steadfastly set in its methods in relation to slurry pump technology.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also often recognized as ‘dynamic’ seals’) and single mechanical seals. All include significant limitations, together with poor reliability, reduced imply instances between failure (MTBF), intensive maintenance necessities and higher operational prices.
These components alone should give mine managers cause 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 administration systems and ISO-50001 Standard for power administration systems should pay attention to the extreme water waste and excessive power consumption that outcomes from choosing these conventional sealing strategies.
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 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 excessive strain, maintaining a secure fluid film between the delicate seal faces to keep them cool and lubricated, whereas forcing the damaging slurry away.
The flush water required in all three sealing approaches is equipped from an exterior source and injected into the process at the next pressure than the stuffing box strain, in line with the trade normal American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the bottom or into the process is sent to the tailings dam. This also has an impact on the water stability of the plant.
This approach constitutes a loss of clear water amounting to billions of gallons a 12 months globally. One large, typical slurry pump typically consumes 10 US gallons (37.eight litres) per minute, amounting to 5.2 million US gallons (19.6 million litres) of water every year – a shocking statistic by any measure.
At a time when world water provide is predicted to fall in need of demand by some 40% by 20301 , removing unnecessary use of this priceless useful resource ought to arguably be a central plank of any accountable sustainability programme. Yet extreme water use, and the upper power consumption it entails, stay embedded within the processes of many mining firms. Worse still, it is fair to say that it is typically accepted as merely ‘par for the course’ by reliability engineers and management alike.
But the precise fact is that water waste on any scale is a completely pointless feature of slurry operations as it may be virtually completely eradicated simply by employing advanced double mechanical seals and fashionable water management support methods.
Improve reliability The sort of seal selected, the surroundings by which it operates, and crucially, the tank assist system which provides the water to maximise seal life, combine to supply the solution to extreme water waste and power use.
Modern double mechanical seals have two units of faces, one sealing to the method fluid and one to ambiance, with a barrier space between the 2. They are designed to fulfill the arduous requirements of heavy obligation slurry purposes, with fortified metallic elements which are extremely proof against corrosion and erosion. Large ports and elevated radial clearances imply the lubrication which is important to optimising seal life is maintained continuously and consistently.
A pressurised barrier tank system is central to the environmental sustainability of this answer. It employs a thermosiphon process which supplies clear, cool water to the barrier space between the double seals at a stress larger than the product strain, making certain a consistent, stable and clear fluid movie to keep the seal faces cool and lubricated.
As the mechanical seals generate warmth, the recent 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 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 reducing leakage to absolutely the 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 need to install particular pump techniques, pressurised barrier tanks offer ratings as a lot as 435 psi (30 bar), making them ideal for these purposes. Self-topping and self-pressurising, they are additionally virtually maintenance-free.
Where no plant water supply is out there for topping up the tank techniques, or the availability has insufficient strain, fluid delivery models may be chosen to provide the barrier fluid to seal faces. These have the added advantages of being able to provide a water/glycol combination or oil to provide freeze protection in extraordinarily cold climates.
Wide-ranging advantages The advantages of upgrading to fashionable sealing options and assist systems were felt by a coal mine in Poland utilizing a slurry pump to provide coal mud at 9 bar (135 psi) to filter press. Flushed packing resulted in huge dilution of product, leading to tremendously elevated filtration times and prices. The pump was sealed with a double mechanical seal designed to satisfy the arduous requirements of the method.
The supporting seal tank system decreased leakage and product dilution to virtually zero. Return on investment was swift and the savings long-term. เครื่องวัดแรงดันเกจที่นิยมใช้ when it comes to water conservation have been equally longlasting and the company’s popularity enhanced.
The mining industry should deal with a troublesome and expensive challenge in relation to maintaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is entirely avoidable.
And when a company can get rid of water waste concurrently increasing reliability and reducing long run operational prices, the choice to upgrade to modern techniques ought to certainly be an ethical imperative in addition to making sound enterprise sense.
Share

Scroll to Top