Water waste is commonly deemed an undesirable, but inevitable by-product of mining processes. Yet trendy pump sealing expertise exists which may just about eliminate this waste whereas conserving vitality, improving pump reliability and attaining long run operational financial savings.
Water is amongst the most important, and more and more imperilled, assets on earth. That much is known and acknowledged by industries throughout the globe.
However, additionally it is some of the unnecessarily squandered sources in mining operations. And whereas the trade has begun to embrace effectivity and sustainability-led advances such as automation and renewable vitality, it stays steadfastly set in its ways in relation to slurry pump technology.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also generally known as ‘dynamic’ seals’) and single mechanical seals. All include vital limitations, together with poor reliability, reduced imply instances between failure (MTBF), intensive upkeep necessities and higher operational costs.
These components alone ought to give mine managers trigger 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 vitality administration systems should pay attention to the excessive water waste and excessive power consumption that results from opting for 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 เครื่องมือความดัน packed pumps it’s essential that packing is flushed with clean water to keep it cool and lubricated, while each single slurry seals and expellers require a supply of cool, clear flush water to be injected into the method at excessive strain, sustaining a steady fluid film between the fragile seal faces to keep them cool and lubricated, whereas forcing the damaging slurry away.
The flush water required in all three sealing approaches is provided from an external supply and injected into the method at the next pressure than the stuffing field pressure, consistent with the trade commonplace American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the ground or into the process is distributed to the tailings dam. This also has an effect on the water steadiness of the plant.
This strategy constitutes a loss of clear water amounting to billions of gallons a year globally. One massive, typical slurry pump sometimes 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 stunning statistic by any measure.
At a time when international water supply is predicted to fall wanting demand by some 40% by 20301 , removing unnecessary use of this useful useful resource ought to arguably be a central plank of any accountable sustainability programme. Yet extreme water use, and the higher energy consumption it entails, stay embedded within the processes of many mining firms. Worse nonetheless, it’s honest to say that it’s typically accepted as simply ‘par for the course’ by reliability engineers and management alike.
But the fact is that water waste on any scale is a completely pointless feature of slurry operations as it could be virtually completely eradicated just by using advanced double mechanical seals and modern water management support systems.
Improve reliability The type of seal chosen, the setting by which it operates, and crucially, the tank support system which supplies the water to maximise seal life, combine to offer the solution to excessive water waste and power use.
Modern double mechanical seals have two sets of faces, one sealing to the process fluid and one to ambiance, with a barrier area between the two. They are designed to satisfy the arduous requirements of heavy responsibility slurry functions, with fortified steel elements which are extremely resistant to corrosion and erosion. Large ports and elevated radial clearances imply 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 space between the double seals at a pressure larger than the product strain, ensuring a constant, secure 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 again down to provide cool lubrication to the seal faces. Most importantly, the flush water is consistently recycled, flowing across the seal faces in a continuous loop and decreasing leakage to absolutely the minimum, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing multiple slurry pumps in a ‘series train’ with out the necessity to set up special pump methods, pressurised barrier tanks supply rankings as a lot as 435 psi (30 bar), making them perfect for these functions. Self-topping and self-pressurising, they are additionally almost maintenance-free.
Where no plant water supply is available for topping up the tank systems, or the supply has insufficient strain, fluid delivery models may be chosen to supply the barrier fluid to seal faces. These have the added benefits of having the ability to supply a water/glycol combination or oil to offer freeze protection in extraordinarily cold climates.
Wide-ranging advantages The benefits of upgrading to trendy sealing options and assist systems were 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 big dilution of product, leading to greatly increased filtration times and costs. pressure gauge ไฮ ด รอ ลิ ค 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 virtually zero. Return on investment was swift and the financial savings long-term. The advantages when it comes to water conservation have been equally longlasting and the company’s status enhanced.
The mining trade should cope with a tricky and expensive challenge in relation to sustaining rotating tools. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is entirely avoidable.
And when an organization can get rid of water waste at the same time as increasing reliability and lowering long term operational costs, the decision to upgrade to trendy systems ought to surely be an ethical crucial as nicely as making sound enterprise sense.
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