Water waste is commonly deemed an unwanted, however inevitable by-product of mining processes. Yet trendy pump sealing know-how exists which might just about eliminate this waste while conserving power, improving pump reliability and achieving long run operational savings.
Water is considered one of the most important, and more and more imperilled, sources on earth. That a lot is known and acknowledged by industries across the globe.
However, additionally ราคาpressuregauge is one of the most unnecessarily squandered sources in mining operations. And while the trade has begun to embrace effectivity and sustainability-led advances similar to automation and renewable vitality, it remains steadfastly set in its methods when it comes to slurry pump expertise.
Three approaches are routinely specified by pump producers to seal slurry pumps: mechanical packing, expellers (also generally recognized as ‘dynamic’ seals’) and single mechanical seals. All come with important limitations, including poor reliability, decreased imply times between failure (MTBF), intensive upkeep requirements and higher 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 techniques and ISO-50001 Standard for energy management techniques ought to take notice of the extreme water waste and excessive power consumption that outcomes from choosing these traditional 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 wasteful elements of slurry processing which is seal flush water injection.
On gland packed pumps it’s important that packing is flushed with clear 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 process at high strain, maintaining a secure fluid movie between the delicate 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 source and injected into the process at a higher stress than the stuffing field stress, according to the industry standard American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the ground or into the process is shipped to the tailings dam. This also has an effect on the water balance of the plant.
This strategy constitutes a loss of clean water amounting to billions of gallons a year globally. One giant, typical slurry pump usually consumes 10 US gallons (37.eight 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 international water supply is predicted to fall in need of demand by some 40% by 20301 , removing pointless use of this valuable resource ought to arguably be a central plank of any responsible sustainability programme. Yet extreme water use, and the upper energy consumption it entails, stay embedded within the processes of many mining companies. Worse nonetheless, it is fair to say that it is usually accepted as merely ‘par for the course’ by reliability engineers and administration alike.
But the very fact is that water waste on any scale is a completely pointless characteristic of slurry operations as it may be almost completely eradicated simply by using advanced double mechanical seals and trendy water management help methods.
Improve reliability The sort of seal chosen, the surroundings during which it operates, and crucially, the tank support system which provides the water to maximise seal life, mix to offer the answer to extreme water waste and energy 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 necessities of heavy obligation slurry functions, with fortified steel elements that are extremely immune to corrosion and erosion. Large ports and increased radial clearances imply the lubrication which is vital to optimising seal life is maintained continuously and constantly.
A pressurised barrier tank system is central to the environmental sustainability of this solution. It employs a thermosiphon course of which supplies clear, cool water to the barrier space between the double seals at a strain larger than the product pressure, making certain a constant, stable and clean fluid movie to maintain the seal faces cool and lubricated.
As the mechanical seals generate heat, the new water within the barrier space 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 constantly recycled, flowing across the seal faces in a continuous loop and lowering leakage to the absolute minimum, 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 methods, pressurised barrier tanks offer scores up to 435 psi (30 bar), making them best for these purposes. Self-topping and self-pressurising, they’re additionally virtually maintenance-free.
Where no plant water supply is available for topping up the tank systems, or the supply has inadequate strain, fluid delivery items could be chosen to provide the barrier fluid to seal faces. These have the added benefits of being ready to provide a water/glycol mixture or oil to provide freeze safety in extremely cold climates.
Wide-ranging advantages The benefits of upgrading to fashionable sealing options and assist systems 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 tremendously increased filtration instances and prices. The pump was sealed with a double mechanical seal designed to fulfill the arduous necessities of the method.
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 status enhanced.
The mining trade should cope with a tricky and dear challenge when it comes to maintaining rotating gear. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is completely avoidable.
And when an organization can remove water waste simultaneously rising reliability and decreasing long term operational prices, the choice to upgrade to trendy techniques should certainly be an ethical imperative as properly as making sound enterprise sense.
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