Water waste is often deemed an unwanted, however inevitable by-product of mining processes. Yet trendy pump sealing expertise exists which might virtually get rid of this waste whereas conserving vitality, enhancing pump reliability and reaching long run operational financial savings.
Water is probably certainly one of the most important, and more and more imperilled, sources on earth. That a lot is understood and acknowledged by industries across the globe.
However, it’s also one of the most unnecessarily squandered assets in mining operations. And while the business has begun to embrace effectivity and sustainability-led advances corresponding to automation and renewable energy, it remains steadfastly set in its methods when it comes to slurry pump know-how.
Three approaches are routinely specified by pump manufacturers to seal slurry pumps: mechanical packing, expellers (also generally known as ‘dynamic’ seals’) and single mechanical seals. All include significant limitations, together with poor reliability, lowered mean times between failure (MTBF), intensive upkeep requirements and better operational prices.
เครื่องมือความดัน should give mine managers cause for a re-evaluation of the sealing strategies used on slurry pumps. However, any firm with a dedication to the International Standards Organisation ISO-14001 Standard for environmental administration systems and ISO-50001 Standard for vitality administration techniques ought to take note of the excessive water waste and excessive power consumption that results from choosing 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 features of slurry processing which is seal flush water injection.
On gland 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, clean flush water to be injected into the method at high stress, maintaining a stable fluid film between the fragile seal faces to maintain them cool and lubricated, whereas forcing the damaging slurry away.
The flush water required in all three sealing approaches is supplied from an exterior supply and injected into the method at the next strain than the stuffing field strain, in line with the business normal American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the ground or into the method is shipped to the tailings dam. This additionally has an impact on the water steadiness of the plant.
This strategy constitutes a lack of clean water amounting to billions of gallons a yr globally. One massive, typical slurry pump sometimes consumes 10 US gallons (37.eight litres) per minute, amounting to five.2 million US gallons (19.6 million litres) of water yearly – a stunning statistic by any measure.
At a time when global water provide is predicted to fall wanting 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 extreme water use, and the higher energy consumption it entails, remain embedded within the processes of many mining companies. Worse nonetheless, it’s honest to say that it’s typically accepted as merely ‘par for the course’ by reliability engineers and management alike.
But the very fact is that water waste on any scale is a very unnecessary function of slurry operations as it can be almost totally eradicated simply by using advanced double mechanical seals and trendy water administration help techniques.
Improve reliability The type of seal chosen, the environment by which it operates, and crucially, the tank help system which provides the water to maximise seal life, combine to offer the answer to excessive water waste and power 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 2. They are designed to satisfy the arduous requirements of heavy duty slurry applications, with fortified steel parts which are extremely resistant to corrosion and erosion. Large ports and increased radial clearances mean the lubrication which is important to optimising seal life is maintained continually and consistently.
A pressurised barrier tank system is central to the environmental sustainability of this answer. It employs a thermosiphon process which supplies clean, cool water to the barrier area between the double seals at a pressure greater than the product stress, making certain a consistent, steady and clear fluid film to keep the seal faces cool and lubricated.
As the mechanical seals generate heat, the hot water within the barrier space rises to the tank and is radiated to the environment, 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 throughout the seal faces in a steady loop and lowering leakage to the absolute minimal, 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 systems, pressurised barrier tanks offer rankings up to 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 provide is on the market for topping up the tank methods, or the supply has inadequate pressure, fluid delivery models can be chosen to produce the barrier fluid to seal faces. These have the added benefits of being in a position to supply a water/glycol combination or oil to provide freeze safety in extremely chilly climates.
Wide-ranging benefits The advantages of upgrading to fashionable sealing solutions and support systems have been 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 huge dilution of product, leading to significantly elevated filtration occasions and prices. The pump was sealed with a double mechanical seal designed to meet the arduous necessities of the process.
The supporting seal tank system reduced leakage and product dilution to just about zero. Return on investment was swift and the savings long-term. The benefits in terms of water conservation have been equally longlasting and the company’s popularity enhanced.
The mining business must take care of a troublesome and expensive problem in phrases of sustaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is totally avoidable.
And when a company can get rid of water waste at the same time as rising reliability and lowering long run operational costs, the choice to upgrade to trendy methods should certainly be a moral imperative as well as making sound enterprise sense.
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