Less waste means more reliability

Water waste is usually deemed an unwanted, however inevitable by-product of mining processes. Yet modern pump sealing know-how exists which might just about eliminate this waste whereas conserving energy, bettering pump reliability and achieving long term operational savings.
Water is among the most significant, and increasingly imperilled, assets on earth. That a lot is known and acknowledged by industries across the globe.
However, it’s also some of the unnecessarily squandered resources in mining operations. And while the trade has begun to embrace efficiency and sustainability-led advances similar to automation and renewable power, it remains 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 known as ‘dynamic’ seals’) and single mechanical seals. All include significant limitations, together with poor reliability, reduced imply instances between failure (MTBF), intensive upkeep necessities and higher operational costs.
These factors alone ought to give mine managers trigger 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 techniques and ISO-50001 Standard for power management techniques should take observe of the excessive water waste and excessive 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 clean water to maintain it cool and lubricated, while both single slurry seals and expellers require a supply of cool, clean flush water to be injected into the method at high strain, maintaining a stable fluid movie 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 equipped from an exterior supply and injected into the process at a better stress than the stuffing field stress, consistent with the industry commonplace 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 additionally has an effect on the water balance of the plant.
This method constitutes a loss of clean water amounting to billions of gallons a yr globally. One massive, typical slurry pump typically 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 world water supply is predicted to fall short of demand by some 40% by 20301 , eradicating pointless use of this priceless useful resource should arguably be a central plank of any accountable sustainability programme. Yet เกจวัดแรงดันเครื่องกรองน้ำ , and the higher energy consumption it entails, stay embedded in the processes of many mining corporations. Worse nonetheless, it is honest to say that it’s 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 very unnecessary function of slurry operations as it can be almost totally eradicated simply by using advanced double mechanical seals and trendy water administration support systems.
Improve reliability The sort of seal chosen, the environment in which it operates, and crucially, the tank support system which provides the water to maximise seal life, combine to provide 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 environment, with a barrier house between the two. They are designed to meet the arduous requirements of heavy duty slurry applications, with fortified metal components that are highly proof against corrosion and erosion. Large ports and elevated radial clearances mean the lubrication which is vital to optimising seal life is maintained constantly and constantly.
A pressurised barrier tank system is central to the environmental sustainability of this answer. It employs a thermosiphon process which provides clean, cool water to the barrier space between the double seals at a pressure higher than the product stress, ensuring a constant, secure and clean fluid movie to maintain 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, permitting the cooler, denser water to sink back down to supply 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 minimal, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing a number of slurry pumps in a ‘series train’ with out the want to set up particular pump methods, pressurised barrier tanks supply scores up to 435 psi (30 bar), making them ideal for these functions. Self-topping and self-pressurising, they’re additionally almost maintenance-free.
Where no plant water supply is available for topping up the tank techniques, or the supply has insufficient strain, fluid delivery units may be selected to provide the barrier fluid to seal faces. These have the added advantages of having the flexibility to provide a water/glycol mixture or oil to supply freeze safety in extremely cold climates.
Wide-ranging advantages The advantages of upgrading to fashionable sealing options and help methods had 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 instances and prices. The pump was sealed with a double mechanical seal designed to satisfy the arduous requirements of the process.
The supporting seal tank system lowered leakage and product dilution to just about zero. Return on investment was swift and the financial savings long-term. The advantages in phrases of water conservation have been equally longlasting and the company’s reputation enhanced.
The mining business should cope with a tricky and dear problem in relation to sustaining rotating tools. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is totally avoidable.
And when a company can remove water waste concurrently growing reliability and reducing long run operational costs, the decision to improve to modern systems ought to surely be a moral imperative in addition to making sound enterprise sense.
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