Water waste is commonly deemed an unwanted, however inevitable by-product of mining processes. Yet fashionable pump sealing expertise exists which can virtually remove this waste while conserving energy, enhancing pump reliability and reaching long term operational savings.
Water is probably one of the most significant, and increasingly imperilled, resources on earth. That much is known and acknowledged by industries throughout the globe.
However, it’s also one of the most unnecessarily squandered assets in mining operations. And whereas เกจวัดแรงดันต่ำ has begun to embrace efficiency and sustainability-led advances such as automation and renewable vitality, it stays steadfastly set in its ways in terms of slurry pump technology.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also often identified as ‘dynamic’ seals’) and single mechanical seals. All come with vital limitations, together with poor reliability, lowered imply occasions between failure (MTBF), intensive upkeep requirements and better operational costs.
These components alone ought to 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 methods and ISO-50001 Standard for vitality administration methods should take note of the excessive water waste and high power consumption that results from opting for these traditional 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 elements 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, clean flush water to be injected into the method at excessive strain, sustaining a stable fluid film 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 equipped from an external supply and injected into the method at a higher strain than the stuffing field stress, in line with the business 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 additionally has an effect on the water balance of the plant.
This strategy constitutes a loss of clear water amounting to billions of gallons a 12 months globally. One massive, standard slurry pump usually consumes 10 US gallons (37.8 litres) per minute, amounting to five.2 million US gallons (19.6 million litres) of water yearly – a shocking statistic by any measure.
At a time when global water supply is predicted to fall wanting demand by some 40% by 20301 , removing unnecessary use of this useful resource should arguably be a central plank of any responsible sustainability programme. Yet extreme water use, and the upper vitality consumption it entails, stay embedded in the processes of many mining corporations. Worse nonetheless, it is honest to say that it is typically accepted as simply ‘par for the course’ by reliability engineers and management alike.
But the very fact is that water waste on any scale is a totally unnecessary characteristic of slurry operations as it can be almost completely eradicated just by employing advanced double mechanical seals and modern water management assist systems.
Improve reliability The sort of seal chosen, the environment in which it operates, and crucially, the tank assist system which supplies the water to maximise seal life, combine to provide the solution to excessive water waste and vitality use.
Modern double mechanical seals have two units of faces, one sealing to the process fluid and one to ambiance, with a barrier house between the 2. They are designed to satisfy the arduous necessities of heavy duty slurry functions, with fortified steel components which are extremely immune to corrosion and erosion. Large ports and increased 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 resolution. เกจวัดแรงดันสูง employs a thermosiphon process which supplies clear, cool water to the barrier house between the double seals at a pressure larger than the product strain, guaranteeing a consistent, secure and clear fluid film to keep the seal faces cool and lubricated.
As the mechanical seals generate heat, the hot water within the barrier house rises to the tank and is radiated to the atmosphere, permitting the cooler, denser water to sink again down to supply 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 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 need to install special pump methods, pressurised barrier tanks offer ratings up to 435 psi (30 bar), making them ideal for these applications. Self-topping and self-pressurising, they’re also virtually maintenance-free.
Where no plant water supply is available for topping up the tank systems, or the supply has insufficient pressure, fluid delivery models may 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 offer freeze safety in extremely cold climates.
Wide-ranging benefits The benefits of upgrading to fashionable sealing options and help 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 large dilution of product, resulting in significantly increased filtration instances and prices. The pump was sealed with a double mechanical seal designed to meet the arduous requirements of the process.
The supporting seal tank system reduced leakage and product dilution to virtually zero. Return on funding was swift and the financial savings long-term. The benefits by method of water conservation have been equally longlasting and the company’s status enhanced.
The mining trade must take care of a tricky and expensive problem in phrases of maintaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and monetary burden which is completely avoidable.
And when a company can eliminate water waste simultaneously growing reliability and decreasing long term operational costs, the decision to upgrade to modern techniques should surely be a moral crucial in addition to making sound business sense.
Share